Light emitting device

Abstract

Provided is a highly reliable light emitting device. The light-emitting device comprises a first electrode, a second electrode and a light-emitting layer, the light-emitting layer is located between the first electrode and the second electrode, the light-emitting layer comprises a first organic compound, a second organic compound and a substance capable of converting triplet excitation energy into light emission, the first organic compound has a pi-electron-deficient heteroaromatic ring, and the second organic compound has a pi-electron-deficient heteroaromatic ring. The second organic compound has a p-electron-rich heteroaromatic ring or aromatic amine skeleton, the first organic compound and the second organic compound contain deuterium, and the difference between the lowest triplet excitation level of the first organic compound and the lowest triplet excitation level of the second organic compound is 0.10 eV or less.

Description

Technical Field

[0001] One aspect of the present invention relates to an organic compound, an organic semiconductor device, a light-emitting device, a photodiode sensor, a display module, a lighting module, a display device, an electronic device, a lighting device, and an electronic device. Note that one aspect of the present invention is not limited to the above technical field. One aspect of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. One aspect of the present invention relates to a process, a machine, a manufacture, or a composition of matter. Thus, more specifically, as an example of the technical field of one aspect of the present invention disclosed in this specification, semiconductor devices, display devices, liquid crystal display devices, lighting devices, power storage devices, storage devices, imaging devices, driving methods of these devices, or manufacturing methods of these devices can be cited. Background Art

[0002] The practical application of light-emitting devices (also referred to as organic EL elements) that use electroluminescence (EL) of organic compounds is very active. In the basic structure of these light-emitting devices, an organic compound layer containing a light-emitting material is sandwiched between a pair of electrodes. By applying a voltage to this device, carriers are injected, and light emission from the light-emitting material can be obtained using the recombination energy of these carriers.

[0003] Since the light-emitting device is a self-luminous device, a display device using this light-emitting device for pixels has higher visibility than a liquid crystal display device and does not require a backlight. In addition, a display device using such a light-emitting device can be manufactured to be thin and light, which is also a great advantage. Moreover, a very fast response speed is also one of its characteristics.

[0004] In addition, since the light-emitting layer of such a light-emitting device can be formed continuously in a planar shape, surface light emission can be obtained. Since this is a characteristic that is difficult to obtain in point light sources typified by incandescent lamps and LEDs or in line light sources typified by fluorescent lamps, the above light-emitting device also has high utility value as a surface light source that can be used for lighting and the like.

[0005] As described above, although display devices and lighting devices using light-emitting devices are applicable to various electronic devices, research and development of light-emitting devices with better characteristics are increasingly active.

[0006] Patent Document 1 discloses a light-emitting device that improves reliability by combining a metal complex and a deuterated host to delay the decomposition mechanism that causes deterioration of the metal complex.

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2022-132158 Summary of the Invention

[0008] One of the objects of one embodiment of the present invention is to provide a light-emitting device having good characteristics. One of the objects of one embodiment of the present invention is to provide a light-emitting device with high reliability. One of the objects of one embodiment of the present invention is to provide a light-emitting device with a low driving voltage. One of the objects of one embodiment of the present invention is to provide a light-emitting device with high reliability and a low driving voltage.

[0009] One of the objects of one embodiment of the present invention is to provide a light-emitting device capable of realizing a display device having good characteristics. One of the objects of one embodiment of the present invention is to provide a light-emitting device capable of providing a display device with high reliability. One of the objects of one embodiment of the present invention is to provide a display device with a low driving voltage. One of the objects of one embodiment of the present invention is to provide a light-emitting device capable of realizing a display device with a low driving voltage and high reliability. One of the objects of one embodiment of the present invention is to provide an organic compound suitable for the above light-emitting device.

[0010] One of the objects of one embodiment of the present invention is to provide any one of an organic semiconductor device, a light-emitting device, a light-receiving device, a display device, an electronic device, and a lighting device with low power consumption. One of the objects of one embodiment of the present invention is to provide any one of an electronic device and a lighting device with high reliability.

[0011] The present invention only needs to achieve any one of the above objects.

[0012] One embodiment of the present invention is a light-emitting device, which includes a first electrode, a second electrode, and a light-emitting layer. The light-emitting layer is located between the first electrode and the second electrode. The light-emitting layer contains a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light. The first organic compound has a π-deficient heteroaromatic ring. The second organic compound has a π-rich heteroaromatic ring or an aromatic amine skeleton. The first organic compound and the second organic compound contain deuterium. The difference between the lowest triplet excitation energy level of the first organic compound and the lowest triplet excitation energy level of the second organic compound is 0.20 eV or less.

[0013] Another aspect of the present invention is a light-emitting device including a first electrode, a second electrode, and a light-emitting layer. The light-emitting layer is located between the first electrode and the second electrode and contains a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light emission. The first organic compound has a π-deficient heteroaromatic ring, the second organic compound contains a π-rich heteroaromatic ring or an aromatic amine skeleton, the first organic compound and the second organic compound contain deuterium, the first organic compound and the second organic compound are a combination that forms an exciplex, and the emission spectrum of the exciplex overlaps with the emission spectrum of the substance capable of converting triplet excitation energy into light emission.

[0014] Another aspect of the present invention is a light-emitting device having the above structure, wherein the difference between the maximum peak wavelength of the emission spectrum of the exciplex and the maximum peak wavelength of the emission spectrum of the substance capable of converting triplet excitation energy into light emission is 30 nm or less.

[0015] Another aspect of the present invention is a light-emitting device including a first electrode, a second electrode, and a light-emitting layer. The light-emitting layer is located between the first electrode and the second electrode and contains a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light emission. The first organic compound has a π-deficient heteroaromatic ring, the second organic compound has a π-rich heteroaromatic ring or an aromatic amine skeleton, the first organic compound and the second organic compound contain deuterium, the phosphorescence emission lifetime or delayed fluorescence lifetime of the first organic compound at 77 K is 1.20 times or more of the phosphorescence emission lifetime or delayed fluorescence lifetime of a third organic compound which is a non-deuterated product of the first organic compound at 77 K, and the phosphorescence emission lifetime or delayed fluorescence lifetime of the second organic compound at 77 K is 1.05 times or more of the phosphorescence emission lifetime or delayed fluorescence lifetime of a fourth organic compound which is a non-deuterated product of the second organic compound at 77 K.

[0016] Another aspect of the present invention is a light-emitting device having the above structure, wherein the peak wavelength of the emission spectrum of the light emitted by the substance capable of converting triplet excitation energy into light emission is 450 nm or more and less than 500 nm. Another aspect of the present invention is a light-emitting device having the above structure, wherein the peak wavelength of the emission spectrum of the light emitted by the substance capable of converting triplet excitation energy into light emission is greater than 600 nm and 700 nm or less.

[0017] Another aspect of the present invention is a light-emitting device including a first electrode, a second electrode, and a light-emitting layer, wherein the light-emitting layer is located between the first electrode and the second electrode, and the light-emitting layer contains a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light emission. The first organic compound has a π-electron-deficient heteroaromatic ring, the second organic compound has a π-electron-rich heteroaromatic ring or an aromatic amine skeleton, the first organic compound and the second organic compound contain deuterium, and the phosphorescence emission lifetime or delayed fluorescence lifetime of the first organic compound at 77K is 1.50 times or more the phosphorescence emission lifetime or delayed fluorescence lifetime of a third organic compound which is a non-deuterated form of the first organic compound at 77K, and the phosphorescence emission lifetime or delayed fluorescence lifetime of the second organic compound at 77K is 3.00 times or more the phosphorescence emission lifetime or delayed fluorescence lifetime of a fourth organic compound which is a non-deuterated form of the second organic compound at 77K.

[0018] Another aspect of the present invention is a light-emitting device having the above structure, wherein the peak wavelength of the emission spectrum of the light emitted by the substance capable of converting triplet excitation energy into light emission is 500 nm or more and 600 nm or less.

[0019] Another aspect of the present invention is a light-emitting device including a first electrode, a second electrode, and a light-emitting layer, wherein the light-emitting layer is located between the first electrode and the second electrode, and the light-emitting layer contains a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light emission. The first organic compound has a π-electron-deficient heteroaromatic ring, the second organic compound has a π-electron-rich heteroaromatic ring or an aromatic amine skeleton, the first organic compound and the second organic compound contain deuterium. In the case where the phosphorescence emission lifetime or delayed fluorescence lifetime of the first organic compound at 77K is X times the phosphorescence emission lifetime or delayed fluorescence lifetime of a third organic compound which is a non-deuterated form of the first organic compound at 77K and the phosphorescence emission lifetime or delayed fluorescence lifetime of the second organic compound at 77K is Y times the phosphorescence emission lifetime or delayed fluorescence lifetime of a fourth organic compound which is a non-deuterated form of the second organic compound at 77K, the value obtained by multiplying X and Y is 1.26 or more.

[0020] Another aspect of the present invention is a light-emitting device including a first electrode, a second electrode, and a light-emitting layer. The light-emitting layer is located between the first electrode and the second electrode and contains a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light. The peak wavelength of the light emitted by the substance capable of converting triplet excitation energy into light is 500 nm or more and 600 nm or less. The first organic compound has a π-electron-deficient heteroaromatic ring, and the second organic compound has a π-electron-rich heteroaromatic ring or an aromatic amine skeleton. The first organic compound and the second organic compound contain deuterium. When the phosphorescence emission lifetime or delayed fluorescence lifetime of the first organic compound at 77 K is X times the phosphorescence emission lifetime or delayed fluorescence lifetime of a third organic compound which is a non-deuterated compound of the first organic compound at 77 K, and the phosphorescence emission lifetime or delayed fluorescence lifetime of the second organic compound at 77 K is Y times the phosphorescence emission lifetime or delayed fluorescence lifetime of a fourth organic compound which is a non-deuterated compound of the second organic compound at 77 K, the value obtained by multiplying X and Y is 4.50 or more.

[0021] Another aspect of the present invention is a light-emitting device including a first electrode, a second electrode, and a light-emitting layer. The light-emitting layer is located between the first electrode and the second electrode and contains a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light. The first organic compound has a π-electron-deficient heteroaromatic ring, and the second organic compound has a π-electron-rich heteroaromatic ring or an aromatic amine skeleton. The first organic compound and the second organic compound contain deuterium. The difference between the 5% weight loss temperature of the first organic compound at 10 Pa and the 5% weight loss temperature of the second organic compound at 10 Pa is 60 °C or less.

[0022] Another aspect of the present invention is a light-emitting device having the above structure, wherein the substance capable of converting triplet excitation energy into light is a phosphorescent substance.

[0023] Another aspect of the present invention is a light-emitting device having the above structure, wherein the first organic compound and the second organic compound are a combination that forms an exciplex.

[0024] Another aspect of the present invention is a light-emitting device having the above structure, wherein the first organic compound is an organic compound having a diazine skeleton or a triazine skeleton, and the second organic compound is an organic compound having a carbazole skeleton.

[0025] Another aspect of the present invention is a light-emitting device having the above structure, wherein the substance capable of converting triplet excitation energy into light contains deuterium.

[0026] Another aspect of the present invention is a light-emitting device having the above structure, which further includes a first layer, wherein the first layer is located between the light-emitting layer and the first electrode, and the first layer contains a fifth organic compound having a π-electron-rich heteroaromatic ring or an aromatic amine skeleton and containing deuterium.

[0027] Another aspect of the present invention is a light-emitting device having the above structure, which further includes a first layer, wherein the first layer is located between the light-emitting layer and the first electrode, the first layer contains a fifth organic compound having a π-electron-rich heteroaromatic ring or an aromatic amine skeleton, the fifth organic compound contains deuterium, and the difference between the lowest triplet excitation energy level of the first organic compound and the lowest triplet excitation energy level of the fifth organic compound is 0.10 eV or less.

[0028] Another aspect of the present invention is a light-emitting device having the above structure, wherein the fifth organic compound is the same as the second organic compound.

[0029] Another aspect of the present invention is a display device including any of the above light-emitting devices.

[0030] Another aspect of the present invention is an electronic device including: the above light-emitting device; and a sensor, an operation button, a speaker, or a microphone.

[0031] Another aspect of the present invention is a lighting device including: the above light-emitting device; and a housing.

[0032] Another aspect of the present invention is the following organic compound.

[0033] [Chemical formula 1]

[0034]

[0035] One aspect of the present invention can provide a light-emitting device with high luminous efficiency. In addition, one aspect of the present invention can provide a light-emitting device with high reliability. In addition, any one of a display device, an electronic device, and a lighting device with low power consumption can be provided. In addition, any one of a display device, an electronic device, and a lighting device with high reliability can be provided. One aspect of the present invention can provide an organic compound with high reliability.

[0036] Note that the description of these effects does not preclude the existence of other effects. Note that one aspect of the present invention does not need to have all of the above effects. Note that effects other than the above can be known and extracted from the descriptions in the specification, drawings, claims, etc. Description of the Drawings

[0037] Figures 1A to 1CSchematic diagram of a light-emitting device according to one embodiment of the present invention;

[0038] Figure 2 Diagram for explaining the calculation method of the light-emitting lifetime;

[0039] Figure 3A and Figure 3B Diagram showing a display device according to one embodiment of the present invention;

[0040] Figure 4A and Figure 4B Diagram showing a display device according to one embodiment of the present invention;

[0041] Figures 5A to 5E Cross-sectional view showing an example of the manufacturing method of a display device;

[0042] Figure 6A and Figure 6B Cross-sectional view showing an example of the manufacturing method of a display device;

[0043] Figures 7A to 7D Cross-sectional view showing an example of the manufacturing method of a display device;

[0044] Figures 8A to 8C Cross-sectional view showing an example of the manufacturing method of a display device;

[0045] Figures 9A to 9C Cross-sectional view showing an example of the manufacturing method of a display device;

[0046] Figures 10A to 10C Cross-sectional view showing an example of the manufacturing method of a display device;

[0047] Figure 11A and Figure 11B Perspective view showing an example of the structure of a display module;

[0048] Figure 12A and Figure 12B Cross-sectional view showing an example of the structure of a display device;

[0049] Figure 13 Perspective view showing an example of the structure of a display device;

[0050] Figure 14 Cross-sectional view showing an example of the structure of a display device;

[0051] Figure 15 Cross-sectional view showing an example of the structure of a display device;

[0052] Figures 16A to 16C Diagram showing an example of the structure of a display device;

[0053] Figure 17is a cross-sectional view showing an example of the structure of a display device;

[0054] Figures 18A to 18C is a diagram showing an example of the structure of a display device;

[0055] Figures 19 to Figure 19D is a diagram illustrating an example of a wearable device;

[0056] Figures 20A to 20F is a diagram showing an example of an electronic device;

[0057] Figures 21A to 21G is a diagram showing an example of an electronic device;

[0058] Figure 22 is a diagram showing the luminance-current density characteristics of light-emitting device 1 and comparative light-emitting devices 1-1 to 1-3;

[0059] Figure 23 is a diagram showing the current efficiency-current density characteristics of light-emitting device 1 and comparative light-emitting devices 1-1 to 1-3;

[0060] Figure 24 is a diagram showing the luminance-voltage characteristics of light-emitting device 1 and comparative light-emitting devices 1-1 to 1-3;

[0061] Figure 25 is a diagram showing the current density-voltage characteristics of light-emitting device 1 and comparative light-emitting devices 1-1 to 1-3;

[0062] Figure 26 is a diagram showing the external quantum efficiency-luminance characteristics of light-emitting device 1 and comparative light-emitting devices 1-1 to 1-3;

[0063] Figure 27 is a diagram showing the blue index (BI)-current density characteristics of light-emitting device 1 and comparative light-emitting devices 1-1 to 1-3;

[0064] Figure 28 is a diagram showing the electroluminescence spectra of light-emitting device 1 and comparative light-emitting devices 1-1 to 1-3;

[0065] Figure 29 is a diagram showing the characteristics of the normalized luminance change over time of light-emitting device 1 and comparative light-emitting devices 1-1 to 1-3;

[0066] Figure 30 is a diagram showing the luminance-current density characteristics of light-emitting device 2 and comparative light-emitting devices 2-1 to 2-3;

[0067] Figure 31 is a graph showing the current efficiency - current density characteristics of the light-emitting device 2 and the comparative light-emitting devices 2-1 to 2-3;

[0068] Figure 32 is a graph showing the luminance - voltage characteristics of the light-emitting device 2 and the comparative light-emitting devices 2-1 to 2-3;

[0069] Figure 33 is a graph showing the current density - voltage characteristics of the light-emitting device 2 and the comparative light-emitting devices 2-1 to 2-3;

[0070] Figure 34 is a graph showing the external quantum efficiency - luminance characteristics of the light-emitting device 2 and the comparative light-emitting devices 2-1 to 2-3;

[0071] Figure 35 is a graph showing the blue index (BI) - current density characteristics of the light-emitting device 2 and the comparative light-emitting devices 2-1 to 2-3;

[0072] Figure 36 is a graph showing the electroluminescence spectra of the light-emitting device 2 and the comparative light-emitting devices 2-1 to 2-3;

[0073] Figure 37 is a graph showing the normalized luminance change characteristics over time of the light-emitting device 2 and the comparative light-emitting devices 2-1 to 2-3;

[0074] Figure 38 is a graph showing the luminance - current density characteristics of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3;

[0075] Figure 39 is a graph showing the current efficiency - current density characteristics of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3;

[0076] Figure 40 is a graph showing the luminance - voltage characteristics of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3;

[0077] Figure 41 is a graph showing the current density - voltage characteristics of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3;

[0078] Figure 42 is a graph showing the external quantum efficiency - luminance characteristics of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3;

[0079] Figure 43It is a graph showing the blue index (BI)-luminance characteristics of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3;

[0080] Figure 44 It is a graph showing the electroluminescence spectra of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3;

[0081] Figure 45 It is a graph showing the characteristics of the normalized luminance change with time of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3;

[0082] Figure 46 It is a graph showing the luminance-current density characteristics of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3;

[0083] Figure 47 It is a graph showing the current efficiency-current density characteristics of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3;

[0084] Figure 48 It is a graph showing the luminance-voltage characteristics of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3;

[0085] Figure 49 It is a graph showing the current density-voltage characteristics of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3;

[0086] Figure 50 It is a graph showing the external quantum efficiency-luminance characteristics of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3;

[0087] Figure 51 It is a graph showing the blue index (BI)-current density characteristics of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3;

[0088] Figure 52 It is a graph showing the electroluminescence spectra of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3;

[0089] Figure 53 It is a graph showing the characteristics of the normalized luminance change with time of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3;

[0090] Figure 54 It is a graph showing the luminance-current density characteristics of the light-emitting device 5 and the comparative light-emitting devices 5-1 to 5-3;

[0091] Figure 55is a diagram showing brightness-voltage characteristics of the light emitting device 5 and comparative light emitting devices 5-1 to 5-3;

[0092] Figure 56 is a graph showing current efficiency-current density characteristics of the light emitting device 5 and comparative light emitting devices 5-1 to 5-3;

[0093] Figure 57 is a graph showing current density-voltage characteristics of the light emitting device 5 and comparative light emitting devices 5-1 to 5-3;

[0094] Figure 58 is a graph showing external quantum efficiency-current density characteristics of the light-emitting device 5 and comparative light-emitting devices 5-1 to 5-3;

[0095] Figure 59 is a diagram showing electroemission spectra of the light emitting device 5 and comparative light emitting devices 5-1 to 5-3;

[0096] Figure 60 is a diagram showing the time-varying characteristics of normalized brightness of the light emitting device 5 and the comparative light emitting devices 5-1 to 5-3;

[0097] Figure 61A and Figure 61B is a diagram showing a method for calculating the lowest triplet excitation energy;

[0098] Figure 62 is a diagram showing PL spectra of SiTrzCz2-d16, PSiCzCz-d15 and their exciplexes;

[0099] Figure 63 is a diagram showing the PL spectra of the exciplexes of PSiCzCz-d15 and SiTrzCz2-d16 and PtON-TBBI;

[0100] Figure 64 It is a diagram showing the PL spectra of the excited complexes of PSiCzCz-d15 and SiTrzCz2-d16 and Pt(mmtBubOcz5m4ppy-d3);

[0101] Figure 65 is a diagram showing PL spectra of 8mpTP-4mDBtPBfpm-d13, βNCCP-d26 and their exciplexes;

[0102] Figure 66 It is a diagram showing the PL spectra of the exciplex of βNCCP-d26 and 8mpTP-4mDBtPBfpm-d13 and Ir(5m4dppy-d3)3;

[0103] Figure 67 It is a figure showing the PL spectra of 8(βN2)-4mDBtPBfpm-d13, PCBBiF-d16 and their exciplexes;

[0104] Figure 68 It is a figure showing the exciplexes of 8(βN2)-4mDBtPBfpm-d13 and PCBBiF-d16 and the PL spectrum of OCPG-006;

[0105] Figure 69 It is a figure showing the luminance-current density characteristics of light-emitting device 6 and comparative light-emitting device 6;

[0106] Figure 70 It is a figure showing the luminance-voltage characteristics of light-emitting device 6 and comparative light-emitting device 6;

[0107] Figure 71 It is a figure showing the current efficiency-current density characteristics of light-emitting device 6 and comparative light-emitting device 6;

[0108] Figure 72 It is a figure showing the current density-voltage characteristics of light-emitting device 6 and comparative light-emitting device 6;

[0109] Figure 73 It is a figure showing the external quantum efficiency-current density characteristics of light-emitting device 6 and comparative light-emitting device 6;

[0110] Figure 74 It is a figure showing the electroluminescence spectra of light-emitting device 6 and comparative light-emitting device 6;

[0111] Figure 75 It is a figure showing the normalized luminance change characteristics over time of light-emitting device 6 and comparative light-emitting device 6;

[0112] Figure 76A and Figure 76B It is a figure showing the 1 1H NMR spectrum of 2,6-dibromonaphthalene;

[0113] Figure 77A and Figure 77B It is a figure showing the 1 1H NMR spectra of 2,6-dibromonaphthalene and 2,6-dibromonaphthalene-d6;

[0114] Figure 78A and Figure 78B It is a figure showing the 1 1H NMR spectrum of 2,6-dibromonaphthalene-d6 and 1,1,2-trichloroethane;

[0115] Figure 79A and Figure 79Bis a diagram showing the 1 1H NMR spectrum of 8(βN2)-4mDBtPBfpm-d13;

[0116] Figure 80 is a diagram showing the absorption spectrum and PL spectrum of a toluene solution of 8(βN2)-4mDBtPBfpm-d13;

[0117] Figure 81 is a diagram showing the absorption spectrum and PL spectrum of a thin film of 8(βN2)-4mDBtPBfpm-d13;

[0118] Figure 82A and Figure 82B is a diagram showing the 1 1H NMR spectrum of FBiPhBr;

[0119] Figure 83A and Figure 83B is a diagram showing the 1 1H NMR spectra of FBiPhBr-d4 and FBiPhBr;

[0120] Figure 84A and Figure 84B is a diagram showing the 1 1H NMR spectrum of PCBBiF;

[0121] Figure 85A and Figure 85B is a diagram showing the 1 1H NMR spectra of PCBBiF-d16 and PCBBiF;

[0122] Figure 86 is a diagram showing the absorption spectrum and PL spectrum of a toluene solution of PCBBiF-d16;

[0123] Figure 87 is a diagram showing the absorption spectrum and PL spectrum of a thin film of PCBBiF-d16. Detailed Embodiments

[0124] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the following description, and it is easily understood by those of ordinary skill in the art that the mode and details can be changed into various forms without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited only to the content described in the embodiments shown below.

[0125] Note that in this specification and the like, a device fabricated using a metal mask or an FMM (Fine Metal Mask, high-precision metal mask) is sometimes referred to as a device having an MM (Metal Mask) structure. In addition, in this specification and the like, a device fabricated without using a metal mask or an FMM is sometimes referred to as a device having an MML (Metal Mask Less) structure.

[0126] Embodiment 1

[0127] The organic semiconductor device includes at least a pair of electrodes (a first electrode and a second electrode) and an organic compound layer, and the organic compound layer includes an active layer or an active region. Preferably, as Figures 1A to 1C shown, the organic compound layer has a stacked structure composed of functional layers with different functions, and the functional layers contain organic compounds having characteristics required for their corresponding functions.

[0128] The above functional layers are required to have multiple functions. As typical examples of the functional layers, for example, a carrier injection layer, a carrier transport layer, an active layer (a light-emitting layer, a photoelectric conversion layer, etc.), a charge generation layer, a carrier blocking layer, an exciton blocking layer, etc. can be cited. In addition, each functional layer may also have other functions. For example, since it is premised that a hole is transported by an electron blocking layer and an electron is transported by a hole blocking layer, it can also be referred to as a carrier transport layer (a hole transport layer or an electron transport layer).

[0129] As described above, each functional layer contains an organic compound having characteristics corresponding to the required function. Therefore, the development of organic compounds having characteristics suitable for each functional layer is becoming increasingly active, and many organic compounds have been developed and put into practical use.

[0130] In addition, the combination of the above organic compounds has a great influence on the characteristics of the light-emitting device. The above light-emitting device structure is also actively studied.

[0131] For example, first, in a current-excited light-emitting device, by using a substance (a phosphorescent light-emitting substance, a substance showing thermally activated delayed fluorescence) capable of converting triplet excitation energy into light as a light-emitting substance (guest material), a light-emitting device with high luminous efficiency can be obtained.

[0132] In addition, the following structure is known: in the light-emitting layer, two different organic compounds (specifically, an organic compound having electron-transporting properties and an organic compound having hole-transporting properties) are used as the host material of the light-emitting layer and used together with the light-emitting substance (guest material).

[0133] Among them, a structure in which an exciplex formed by two different organic compounds is used as an energy donor in the light-emitting layer and a substance that can convert triplet excitation energy into luminescence (phosphorescent substance, substance exhibiting thermally activated delayed fluorescence) is used as an energy acceptor, namely the so-called ExTET (Exciplex-Triplet Energy Transfer), which is an excellent technology that can simultaneously achieve high efficiency, low driving voltage and long life.

[0134] That is, a light-emitting device containing an exciplex serving as an energy donor and a substance capable of converting triplet excitation energy into light emission serving as an energy acceptor (ie, a light-emitting substance) in a light-emitting layer can have very good characteristics.

[0135] Here, when both of the two organic compounds (the first organic compound and the second organic compound) used as the host material contain deuterium, a light-emitting device with higher reliability can be realized. In particular, as described later, at the lowest triplet excitation energy level (T 1 energy level) and the T of the second organic compound 1 When the difference in energy levels is small, that is, when the T 1 Energy level and T of the second organic compound 1 When the energy levels are close, triplet excitation energy is not easily concentrated in a certain organic compound, and energy transfer from the triplet excitation state of each compound to a substance capable of converting triplet excitation energy into luminescence may occur. The energy transfer efficiency from each compound is improved due to the influence of deuterium, so the degradation of the first organic compound and the second organic compound containing deuterium can be suppressed.

[0136] This effect is particularly significant when the two organic compounds form an exciplex. Regarding the singlet excitation energy of the exciplex, the singlet excitation energy of the exciplex is lower than the singlet excitation energy of the first organic compound and the second organic compound, so energy is transferred from the exciplex to the luminescent substance. However, the triplet excitation energy of the exciplex can not only be directly transferred to the luminescent substance, but there may also be a path for indirect energy transfer through the triplet excited state of the first organic compound and / or the second organic compound. In particular, as described later, in the case of the T of the first organic compound containing deuterium, 1 Energy level and T of the second organic compound 1 When the difference in energy levels is small, that is, when the T 1 Energy level and T of the second organic compound 1When the energy levels are close, energy may be transferred through the triplet excited states of the respective compounds to a substance that can convert triplet excitation energy into light emission. This is because the excitation energy is not easily concentrated in a certain organic compound. Since the energy transfer efficiency from the triplet excited states of the respective compounds is improved due to the influence of deuterium, deterioration of the first organic compound and the second organic compound containing deuterium can be suppressed.

[0137] Accordingly, compared with a light-emitting device using an exciplex formed of an organic compound not deuterated as an energy donor, deterioration of a light-emitting device using an exciplex formed of a deuterated organic compound as an energy donor is suppressed, and thus a highly reliable light-emitting device can be realized.

[0138] Note that the first organic compound and the second organic compound may each be an organic compound containing both hydrogen and deuterium or an organic compound containing deuterium but not containing hydrogen.

[0139] In addition, although the entire molecules of the first organic compound and the second organic compound may be deuterated, it is preferable that a group or a skeleton in which the lowest triplet excitation energy levels are concentratedly distributed is deuterated. Thereby, the first organic compound or the second organic compound can be obtained by a method cheaper than the method of deuterating the entire molecule.

[0140] In the present specification, "containing deuterium" means a state in which the proportion of deuterium in hydrogen and deuterium contained in an organic compound is significantly higher than the natural abundance ratio of deuterium, specifically, 500 times or more the natural abundance ratio, and "deuterated organic compound" means an organic compound in which the proportion of deuterium in hydrogen and deuterium contained in the organic compound is significantly higher than the natural abundance ratio of deuterium, specifically, 500 times or more the natural abundance ratio of deuterium. In addition, this ratio does not refer to the ratio relative to one molecule, but refers to the average of a plurality of target organic compounds present in a certain region.

[0141] Note that preferably, the first organic compound is an organic compound having electron-transporting properties and having a π-deficient heteroaromatic ring. In addition, preferably, the second organic compound is an organic compound having hole-transporting properties and having a π-rich heteroaromatic ring or an aromatic amine skeleton.

[0142] When the first organic compound and the second organic compound in a light-emitting device according to one embodiment of the present invention contain deuterium, the energy transfer efficiency is improved because the phosphorescence lifetime or the delayed fluorescence lifetime of the deuterated organic compound is longer than the phosphorescence lifetime or the delayed fluorescence lifetime of the organic compound not deuterated. This is because the intramolecular vibration of the lowest triplet excited state (T 1 state) of the deuterated organic compound is suppressed compared with the intramolecular vibration of the organic compound not deuterated, and thus from T 1Non-radiative transfer of the state to a more stable state is suppressed.

[0143] The energy transfer efficiency from an energy donor (an exciplex in one embodiment of the present invention) to an energy acceptor (a substance capable of converting triplet excitation energy into luminescence in one embodiment of the present invention) is represented by the following formula (1). From this formula, it can be seen that in order to improve the energy transfer efficiency the rate constant k of energy transfer can be increased h*→g , so that the other competing rate constants k r +k nr (=1 / τ) become relatively small.

[0144] Note that in formula (1), k r represents the rate constant of the luminescence process of the energy donor (fluorescence when discussing energy transfer from the singlet excited state, phosphorescence or delayed fluorescence when discussing energy transfer from the triplet excited state), k nr represents the rate constant of the non-luminescence process (thermal deactivation and intersystem crossing) of the energy donor, and τ represents the measured lifetime of the excited state of the energy donor. In addition, k h*→g represents the rate constant of energy transfer (Förster mechanism or Dexter mechanism).

[0145] [Formula 1]

[0146]

[0147] The atomic configurations, spectral shapes, etc. of the molecules in the deuterated organic compound and the non-deuterated organic compound are almost unchanged, so the rate constant k of energy transfer h*→g is substantially the same (refer to the following formula 2 or formula 3). Therefore, it can be known that when comparing the deuterated organic compound and the non-deuterated organic compound, the rate constant k of energy transfer h*→g is greatly affected by the luminescence lifetime (phosphorescence lifetime or delayed fluorescence lifetime) τ. That is, when the luminescence lifetime (phosphorescence lifetime or delayed fluorescence lifetime) becomes longer, the energy transfer efficiency is improved.

[0148] [Formula 2]

[0149]

[0150] [Formula 3]

[0151]

[0152] Formula (2) is the formula for the rate constant k h*→g of the Förster mechanism, and formula (3) is the formula for the rate constant k h*→g of the Dexter mechanism.

[0153] In formula (2), ν represents the vibration number, f’ h (ν) represents the normalized emission spectrum of the host material (fluorescence spectrum when discussing energy transfer from the singlet excited state, phosphorescence spectrum when discussing energy transfer from the triplet excited state), ε g (ν) represents the molar extinction coefficient of the guest material, N represents Avogadro's number, n represents the refractive index of the medium, R represents the intermolecular distance between the host material and the guest material, τ represents the measured lifetime of the excited state (fluorescence lifetime, phosphorescence lifetime), represents the luminescence quantum yield (fluorescence quantum yield when discussing energy transfer from the singlet excited state, phosphorescence quantum yield when discussing energy transfer from the triplet excited state), K 2 is a coefficient (from 0 to 4) representing the orientation of the transition dipole moments of the host material and the guest material. Note that in the random orientation, K 2 = 2 / 3.

[0154] In formula (3), h is Planck's constant, K is a constant with the energy dimension, ν represents the vibration number, f’ h (ν) represents the normalized emission spectrum of the host material (fluorescence spectrum when discussing energy transfer from the singlet excited state, phosphorescence spectrum when discussing energy transfer from the triplet excited state), ε’ g (ν) represents the normalized absorption spectrum of the guest material, L represents the effective molecular radius, R represents the intermolecular distance between the host material and the guest material.

[0155] As described above, in the energy transfer from the first organic compound and the second organic compound, the energy transfer efficiency from the triplet excited state of each is very important, so the lifetime of the triplet excited state is very important. In other words, by extending the phosphorescence lifetime or delayed fluorescence lifetime of the deuterated first organic compound and the second organic compound, the energy transfer efficiency is improved, and the deterioration of the deuterated organic compound can be suppressed. Thus, compared with a light-emitting device including an energy donor using a non-deuterated organic compound, the deterioration of the organic compound in a light-emitting device including an energy donor using a deuterated organic compound is suppressed, and thus a highly reliable light-emitting device can be realized.

[0156] In addition, in the light-emitting device according to one embodiment of the present invention, an exciplex formed from a first organic compound and a second organic compound is used as an energy donor. However, as described above, with respect to the triplet excitation energy, there may be a path for energy transfer from the triplet excited state of the exciplex through the triplet excited states of the first organic compound and the second organic compound. Therefore, the phosphorescence lifetime or delayed fluorescence lifetime of the first organic compound and the second organic compound forming the exciplex is important. Here, it is understood that in the light-emitting device according to one embodiment of the present invention, when the phosphorescence lifetime or delayed fluorescence lifetime is extended by a certain value or more due to both the first organic compound and the second organic compound containing deuterium, the reliability of the light-emitting device using the exciplex as an energy donor is significantly improved. In addition, when comparing the lifetimes, it is preferable to use the same measurement conditions. For example, it is preferable to compare with the same sample shape as when comparing between thin films or between solutions. In addition, when comparing the phosphorescence lifetime, a sample measured at a low temperature (any temperature in the range of 4K to 80K) is used, and when comparing the delayed fluorescence lifetime, a sample measured at room temperature (any temperature in the range of 290K to 300K) is used.

[0157] That is, preferably, the phosphorescence lifetime or delayed fluorescence lifetime of the first organic compound is 1.20 times or more the phosphorescence lifetime or delayed fluorescence lifetime of a third organic compound which is a non-deuterated form of the first organic compound, and the phosphorescence lifetime or delayed fluorescence lifetime of the second organic compound is 1.05 times or more the phosphorescence lifetime or delayed fluorescence lifetime of a fourth organic compound which is a non-deuterated form of the second organic compound. At this time, preferably, the light emitted by the substance (the light-emitting substance contained in the light-emitting layer) capable of converting the triplet excitation energy into light is light emission in the blue region, that is, its peak wavelength is typically 450 nm or more and less than 500 nm. Alternatively, preferably, the light emitted by the substance (the light-emitting substance contained in the light-emitting layer) capable of converting the triplet excitation energy into light is light emission in the red region, that is, its peak wavelength is typically more than 600 nm and 700 nm or less.

[0158] Alternatively, preferably, the phosphorescence lifetime or delayed fluorescence lifetime of the first organic compound is 1.50 times or more the phosphorescence lifetime or delayed fluorescence lifetime of a third organic compound which is a non-deuterated form of the first organic compound, and the phosphorescence lifetime or delayed fluorescence lifetime of the second organic compound is 3.00 times or more the phosphorescence lifetime or delayed fluorescence lifetime of a fourth organic compound which is a non-deuterated form of the second organic compound. At this time, preferably, the light emitted by the substance (the light-emitting substance contained in the light-emitting layer) capable of converting the triplet excitation energy into light is light emission in the green region, that is, its peak wavelength is typically 500 nm or more and 600 nm or less.

[0159] In addition, in the light-emitting device according to one embodiment of the present invention, when the value obtained by multiplying the magnification factors when the phosphorescence lifetime or delayed fluorescence lifetime becomes long because both the first organic compound and the second organic compound contain deuterium is equal to or greater than a certain value, the reliability of the light-emitting device using the exciplex as an energy donor is significantly improved.

[0160] In other words, in the light-emitting device according to one embodiment of the present invention, when the phosphorescence lifetime of the first organic compound is X times the phosphorescence lifetime of the third organic compound which is a non-deuterated compound of the first organic compound and the phosphorescence lifetime of the second organic compound is Y times the phosphorescence lifetime of the fourth organic compound which is a non-deuterated compound of the second organic compound, it is preferable to use the first organic compound and the second organic compound for which the value obtained by multiplying X and Y is 1.26 or more.

[0161] In addition, when the phosphorescence lifetime or delayed fluorescence lifetime of the first organic compound is X times the phosphorescence lifetime or delayed fluorescence lifetime of the third organic compound which is a non-deuterated compound of the first organic compound and the phosphorescence lifetime or delayed fluorescence lifetime of the second organic compound is Y times the phosphorescence lifetime or delayed fluorescence lifetime of the fourth organic compound which is a non-deuterated compound of the second organic compound, by using the first organic compound and the second organic compound for which the value obtained by multiplying X and Y is equal to or greater than a certain value, a light-emitting device having better characteristics can be obtained, and thus it is preferable.

[0162] Specifically, in the case where the light emitted by the substance capable of converting triplet excitation energy into light (the light-emitting substance contained in the light-emitting layer) is light emission in the green region, that is, when its peak wavelength is typically 500 nm or more and 600 nm or less, by using the first organic compound and the second organic compound for which the value obtained by multiplying X and Y is 4.50 or more, a light-emitting device having better characteristics can be obtained, and thus it is preferable.

[0163] Alternatively, in the case where the light emitted by the substance capable of converting triplet excitation energy into light (the light-emitting substance contained in the light-emitting layer) is light emission in the blue region, that is, when its peak wavelength is typically 450 nm or more and less than 500 nm, it is preferable to use the first organic compound and the second organic compound for which the value obtained by multiplying X and Y is 1.26 or more. Alternatively, in the case where the light emitted by the substance capable of converting triplet excitation energy into light (the light-emitting substance contained in the light-emitting layer) is light emission in the red region, that is, when its peak wavelength is typically greater than 600 nm and 700 nm or less, it is preferable to use the first organic compound and the second organic compound for which the value obtained by multiplying X and Y is 1.26 or more.

[0164] Time-resolved measurement is performed by measuring the luminescence intensity that decays after the excitation light is blocked by a shutter at regular time intervals, and the phosphorescence lifetime and delayed fluorescence lifetime are calculated by measuring the transient PL. At this time, a fluorescence component is mixed in the initial stage of the decay, and sometimes the shape of the graph is not a straight line. In this case, a starting point is set in the straight-line part of the graph, and the time required for the intensity at the starting point to decay to 1 / e is denoted as the phosphorescence lifetime or delayed fluorescence lifetime.

[0165] As Figure 2 shown, referring to the measurement data ( Figure 2 the left figure in Figure 2 ), within the range of the straight line in the graph, t = 0 (here, the time when the light quantity reaches 50% of the measurement start time is set as t = 0) ( Figure 2 the right figure in

[0166] is set as the starting point. The time when the above light quantity decays to 1 / e of that at t = 0 is denoted as the phosphorescence lifetime or delayed fluorescence lifetime. In Figure 2 , a graph is plotted with the time when the intensity reaches 50% of the measurement start time in the measurement data as time 0 s, and when the light quantity at 0 s is denoted as 1, the time when the light quantity becomes 1 / e is denoted as the phosphorescence lifetime or delayed fluorescence lifetime. Note that it is easy to handle when using the intensity of 50% of the measurement start time as the starting point, but other values can also be used.

[0166] As the measurement of the phosphorescence lifetime, for example, a liquid nitrogen cooling device can be set in a fluorescence photometer such as FP-8600 manufactured by JASCO Corporation and performed at liquid nitrogen temperature (77K). The material is prepared in a glove box, the sample is dissolved in deoxygenated 2-MeTHF, and stirred at room temperature for about 30 minutes using a stirrer (when using a material that is not easily soluble, heating is also performed), and a solution with a concentration of about 1.2E -4 M can be prepared.

[0167] Time-resolved measurement can be performed by the following method: irradiate the sample cell with excitation light for about 30 seconds, and measure the luminescence intensity that decays after the excitation light is blocked by the light at intervals of 10 ms. The wavelength for measuring the phosphorescence lifetime is preferably the peak wavelength of the phosphorescence spectrum. When the phosphorescence spectrum has multiple peaks, it is preferable to select the wavelength with a high peak intensity. Depending on the wavelength, sometimes accurate measurement cannot be performed due to the mixing of the fluorescence spectrum. In this case, it is preferable to select a phosphorescence wavelength that does not overlap with the fluorescence as much as possible by comparing the emission spectrum measured at low temperature (e.g., 77K) (the emission spectrum including phosphorescence) with the emission spectrum measured at room temperature (the emission spectrum not including phosphorescence and only including fluorescence). Or, the peak wavelength with the longest wavelength among the peaks of the phosphorescence spectrum can be selected. When using a frozen solution, luminescence from other than the lowest triplet excited state may sometimes be observed. In this case, the peak wavelength with the longest wavelength can be selected.

[0168] In addition, the excitation wavelength can be appropriately selected within a wavelength range not affected by the solvent. As long as the material can be sufficiently excited, it is preferably measured at a wavelength of 330 nm because it is not affected by the solvent. In addition, the bandwidths of the excitation light and the measurement light can be about 10 nm.

[0169] Since it is ideal for the luminescence to decay in a single exponential function, a starting point can be set in the linear part of the graph, and the time when the intensity decays to 1 / e at this starting point is defined as the phosphorescence lifetime or the delayed fluorescence lifetime.

[0170] Note that the fluorescence lifetime, the phosphorescence lifetime, and the delayed fluorescence lifetime can be identified according to the length of the lifetime during time-resolved measurement. The luminescence lifetime with a lifetime of about n seconds is the fluorescence lifetime, and the luminescence lifetime with a lifetime of μ seconds to m seconds or more is the phosphorescence lifetime and the delayed fluorescence lifetime.

[0171] In addition, the reliability of the light-emitting device according to one embodiment of the present invention is improved as the phosphorescence lifetimes (i.e., the lifetimes of triplet excitons) of the first organic compound and the second organic compound are extended. The lifetime of the triplet exciton is extended because the vibration due to deuteration is suppressed and the non-radiative deactivation of the triplet excitation energy is suppressed. At this time, since the T 1 energy level of the first organic compound and the T 1 energy level of the second organic compound have a small difference, the excitation energy is not easily concentrated in a certain organic compound, and significant deterioration of a certain organic compound can be prevented. Therefore, the reliability of the light-emitting device is improved, which is preferable. Specifically, the difference between the T 1 energy level of the first organic compound and the T 1 energy level of the second organic compound is 0.20 eV or less, preferably 0.15 eV or less, and more preferably 0.10 eV or less.

[0172] In addition, the T 1 energy level can be calculated, for example, by depositing a 50-nm sample on a quartz substrate to form a thin film and measuring the emission spectrum (phosphorescence spectrum) at a measurement temperature of 10 K. Preferably, a microscopic PL device LabRAM HR-PL (Horiba, Ltd.) is used in the measurement, and a He-Cd laser (325 nm) is used as the excitation light. Note that the emission end can be calculated by drawing a tangent at the value where the slope on the short-wavelength side of the peak (or shoulder peak) observed at the shortest wavelength of the emission spectrum (phosphorescence spectrum) is the largest and based on the intersection of this tangent with the horizontal axis (wavelength) or the baseline.

[0173] In addition, in one embodiment of the present invention, the sublimation temperature of the first organic compound is preferably close to the sublimation temperature of the second organic compound. For example, the difference between the 5% weight loss temperature of the first organic compound measured by thermogravimetry and the 5% weight loss temperature of the second organic compound measured by thermogravimetry is preferably 60 °C or less. More preferably, it is 45 °C or less, still more preferably 20 °C or less, and further preferably 10 °C or less. Thereby, a material obtained by mixing the first organic compound and the second organic compound can be used for evaporation coating, so the number of evaporation sources can be reduced, and a light-emitting device having good characteristics can be provided at low cost. Note that the 5% weight loss temperature may be a value calculated under atmospheric pressure, but is preferably a value calculated under conditions close to the pressure during evaporation coating. For example, it is preferably a value calculated in a state where the pressure is about 10 Pa.

[0174] The 5% weight loss temperature can be calculated from the relationship between weight and temperature (thermogravimetry) by performing thermogravimetry-differential thermal analysis (TG-DTA: Thermogravimetry-Differential Thermal Analysis). Note that when the pressure during evaporation coating is predetermined, it is preferable to use the value measured under that pressure.

[0175] In addition, by combining the difference in T 1 energy levels, the difference in sublimation temperatures, the phosphorescence lifetime, or the delayed fluorescence lifetime due to the extension rate and product of deuteration of the first organic compound and the second organic compound, a light-emitting device having better characteristics can be realized.

[0176] In addition, the photoluminescence (PL) spectrum of the exciplex formed by the first organic compound and the second organic compound preferably overlaps with the PL spectrum of the light-emitting substance (a substance capable of converting triplet excitation energy into light emission). This is because the excitation energy of the exciplex as an energy donor is close to the excitation energy of the light-emitting substance, and the driving voltage of the light-emitting device can be reduced. Therefore, the difference between the maximum peak wavelengths of the PL spectrum of the exciplex and the PL spectrum of the light-emitting substance is preferably 30 nm or less. Alternatively, when the light-emitting device has a structure in which the wavelength of the light-emitting end on the short-wavelength side of the PL spectrum of the exciplex and the wavelength of the light-emitting end on the short-wavelength side of the PL spectrum of the light-emitting substance differ by 30 nm or less, the driving voltage can be reduced, so it is preferable.

[0177] The PL spectrum of the exciplex is preferably measured using a co-evaporated film of a first organic compound and a second organic compound. The state of the sample when measuring the PL spectrum of a luminescent substance (a substance capable of converting triplet excitation energy into luminescence) can be a thin film or a solution, but from the viewpoint of verifying the state of isolated molecules, a solution is preferably used. When comparing using the same solvent, there is no particular limitation on the solvent for this solution, but a less polar solvent such as toluene or chloroform is preferably used.

[0178] Note that when the light emitted by a substance capable of converting triplet excitation energy into luminescence (luminescent substance contained in the light-emitting layer) is luminescence in the blue region, that is, when its peak wavelength is typically 450 nm or more and less than 500 nm, preferably, an organic compound having a triazine skeleton or a diazine skeleton is used as the first organic compound, and an organic compound having a carbazole skeleton is used as the second organic compound. Specifically, as the first organic compound, 9,9’-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole-1,2,3,4,5,6,7,8,1’,2’,3’,4’,5’,6’,7’,8’-d 16 )(abbreviation: SiTrzCz2-d16) can be mentioned, and as the second organic compound, 9-[3-(triphenylsilyl)phenyl]-3,9’-(bi-9H-carbazole-d15) (abbreviation: PSiCzCz-d15), 9’-[3-(triphenylsilyl)phenyl]-9’H-9,3’:6’,9”-tricarbazole-1,1’,1”,2,2’,2”,3,3”,4,4’,4”,5,5’,5”,6,6”,7,7’,7”,8,8’,8”-d22 (abbreviation: PSiCzGI-d22), etc. can be mentioned.

[0179] In addition, when the light emitted by a substance capable of converting triplet excitation energy into luminescence (luminescent substance contained in the light-emitting layer) is luminescence in the green region, that is, when its peak wavelength is typically 500 nm or more and 600 nm or less, it is preferable to use an organic compound having a diazine skeleton or a triazine skeleton as the first organic compound, and an organic compound having a carbazole skeleton as the second organic compound. Specifically, examples of the first organic compound include 8-(1,1':4',1"-terphenyl-3-yl-2,4,5,6,2',3',5',6',2",3",4",5",6"-d13)-4-[3-(dibenzothiophen-4-yl-1,2,3,6,7,8,9-d7)phenyl-2,4,6-d3]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8mpTP-4mDBtPBfpm-d23), 8-(1,1':4',1"-terphenyl-3-yl-2,4,5,6,2',3',5',6',2",3",4",5",6"-d13)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8mpTP-4mDBtPBfpm-d13), 11-[4-(biphenyl-4-yl-2,2',3,3',4',5,5',6,6'-d9)-6-(phenyl-2,3,4,5,6-d5)-1,3,5-triazin-2-yl]-11,12-dihydro-12-(biphenyl-3-yl)indolo[2,3-a]carbazole-1,2,3,4,5,6,7,8,9,10-d10, and examples of the second organic compound include 9-(2-naphthyl-1,3,4,5,6,7,8-d7)-9'-(phenyl-2,3,4,5,6-d5)-3,3'-bi-9H-carbazole-1,1',2,2',4,4',5,5',6,6',7,7',8,8'-d14 (abbreviation: βNCCP-d26), 9-phenyl-9'-(phenyl-2,3,4,5,6-d5)-3,3'-bis(9H-carbazole) (abbreviation: PCCP-d5), etc.

[0180] This embodiment can be used in any combination with other embodiments.

[0181] Embodiment 2

[0182] In this embodiment, a light-emitting device, which is an organic semiconductor device as one aspect of the present invention, will be described in detail. Figure 1AFIG. showing a light-emitting device according to an aspect of the present invention. The light-emitting device according to an aspect of the present invention includes an organic compound layer 103 between a first electrode 101 formed on an insulating layer 1000 and a second electrode 102 opposed to the first electrode 101. The organic compound layer 103 includes at least a light-emitting layer 113 and may also include other functional layers. In Figure 1A and Figure 1B , an example including a hole injection layer 111, a hole transport layer 112, an electron transport layer 114, and an electron injection layer 115 is shown, and an exciton blocking layer, a charge generation layer, etc. may also be included. In particular, sometimes the layer in the hole transport layer 112 in contact with the light-emitting layer 113 is referred to as an electron blocking layer, and the layer in the electron transport layer 114 in contact with the light-emitting layer 113 is referred to as a hole blocking layer. In the present embodiment, the case where the first electrode 101 is used as an anode and the second electrode 102 is used as a cathode is described as an example, but the opposite may also be true.

[0183] In addition, the light-emitting layer has the structure described in Embodiment 1. Thus, the light-emitting device according to an aspect of the present invention can be a highly reliable light-emitting device.

[0184] The anode is preferably formed of a metal, alloy, conductive compound, or a mixture thereof having a large work function (specifically, 4.0 eV or more). Specifically, for example, indium tin oxide (ITO: Indium Tin Oxide), indium tin silicon oxide containing silicon or silicon oxide (ITSO: Indium Tin Silicon Oxide), indium zinc oxide, indium oxide containing tungsten oxide and zinc oxide (IWZO), etc. can be cited. Although these conductive metal oxide films are usually formed by sputtering, sol-gel methods or the like can also be applied. As an example of the forming method, a method of forming indium zinc oxide by sputtering using a target in which 1 wt% to 20 wt% of zinc oxide is added to indium oxide can be cited. In addition, indium oxide containing tungsten oxide and zinc oxide (IWZO) can be formed by sputtering using a target in which 0.5 wt% to 5 wt% of tungsten oxide and 0.1 wt% to 1 wt% of zinc oxide are added to indium oxide. In addition, as materials for the anode, for example, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), titanium (Ti), aluminum (Al), or nitrides of metal materials (e.g., titanium nitride), etc. can be cited. In addition, the anode can also be a layer in which the above materials are laminated. For example, a film in which Al, Ti, and ITSO are laminated in sequence on Ti has high efficiency due to good reflectivity and can achieve a high resolution of several thousand ppi, and thus is preferred. In addition, graphene can also be used as a material for the anode. In addition, by using a composite material that can form the hole injection layer 111 described later for the layer in contact with the anode (typically the hole injection layer), there is no need to consider the work function when selecting the electrode material.

[0185] The hole injection layer 111 is in contact with the anode and has a function of facilitating the injection of holes into the organic compound layer 103. The hole injection layer 111 can be formed using the following substances: phthalocyanine compounds or complexes such as phthalocyanine (abbreviation: H 2 Pc), copper phthalocyanine (abbreviation: CuPc), etc.; aromatic amine compounds such as 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), 4,4'-bis(N-{4-[N'-(3-methylphenyl)-N'-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNTPD), etc.; or polymers such as poly(3,4-ethylenedioxythiophene) / polystyrenesulfonic acid (abbreviation: PEDOT / PSS), etc.

[0186] In addition, the hole injection layer 111 can also be formed of a substance having an electron-accepting property. As the substance having an accepting property, an organic compound having an electron-withdrawing group (halogen group, cyano group, etc.) can be used, and examples thereof include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviation: F6-TCNNQ), 2-(7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyrene-2-ylidene) malononitrile, and the like. In particular, compounds such as HAT-CN in which an electron-withdrawing group is bonded to a fused aromatic ring having a plurality of heteroatoms are thermally stable, and thus are preferred. In addition, the [3]axisene derivative including an electron-withdrawing group (especially a halogen group such as a fluorine group, a cyano group, etc.) has a very high electron-accepting property, and thus is particularly preferred. Specifically, examples thereof include α,α’,α”-1,2,3-cyclopropanetriyltris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α,α’,α”-1,2,3-cyclopropanetriyltris[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], α,α’,α”-1,2,3-cyclopropanetriyltris[2,3,4,5,6-pentafluorobenzeneacetonitrile], and the like. As the substance having an accepting property, in addition to the above organic compounds, transition metal oxides such as molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, and manganese oxide can be used. In addition, the hole injection layer 111 can be formed using the following substances: phthalocyanine compounds or complexes such as phthalocyanine (abbreviation: H 2 Pc), copper phthalocyanine (abbreviation: CuPc), etc.; aromatic amine compounds such as 4,4’-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), 4,4’-bis(N-{4-[N’-(3-methylphenyl)-N’-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNTPD), etc.; or polymers such as poly(3,4-ethylenedioxythiophene) / polystyrene sulfonic acid (abbreviation: PEDOT / PSS), etc. The substance having an acceptor property can extract electrons from an adjacent hole transport layer (or hole transport material) by applying an electric field.

[0187] In addition, the hole injection layer 111 is preferably formed of a composite material including the above-mentioned material having an acceptor property and a substance having a hole transport property.

[0188] As a substance having hole transport properties for a composite material, various organic compounds such as aromatic amine compounds, heteroaromatic compounds, aromatic hydrocarbons, and high molecular weight compounds (oligomers, dendrimers, polymers, etc.) can be used. As a substance having hole transport properties for a composite material, it is preferable to use a substance having a hole mobility of 1×10 -6 cm 2 / Vs or more. The substance having hole transport properties for a composite material is preferably a compound containing a fused aromatic hydrocarbon ring or a π-electron rich heteroaromatic ring. As the fused aromatic hydrocarbon ring, an anthracene ring, a naphthalene ring, etc. are preferable. In addition, as the π-electron rich heteroaromatic ring, a fused aromatic ring containing at least one of a pyrrole skeleton, a furan skeleton, and a thiophene skeleton is preferable, and specifically, a carbazole ring, a dibenzothiophene ring, or a ring in which these rings are further fused with an aromatic ring or a heteroaromatic ring is preferable.

[0189] Such a substance having hole transport properties preferably has any one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton. In particular, it can be an aromatic amine having a substituent including a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine including a naphthalene ring, or an aromatic monoamine in which 9-fluorenyl is bonded to the nitrogen of the amine through an arylene group. Note that when these substances having hole transport properties are substances including N,N-bis(4-biphenyl)amino, a light emitting device having a long lifetime can be manufactured, so they are preferable.

[0190] As the above-mentioned hole-transporting substances, specifically, N-(4-biphenyl)-6, N-diphenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf), 4,4'-bis(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)-4''-phenyltriphenylamine (abbreviation: BnfBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf(8)), N,N-bis(4-biphenyl)benzo[b]naphtho[2,3-d]furan-4-amine (abbreviation: BBABnf(II)(4)), N,N-bis[4-(dibenzofuran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB1TP), N-[4-(dibenzothiophene-4-yl)phenyl]-N-phenyl-4-biphenylamine (abbreviation: ThBA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenylamine (abbreviation: BBAβNB), 4-[4-(2-naphthyl)phenyl]-4',4''-diphenyltriphenylamine (abbreviation: BBAβNBi), 4,4'-diphenyl-4''-(6;1'-binaphthalen-2-yl)triphenylamine (abbreviation: BBAαNβNB), 4,4'-diphenyl-4''-(7;1'-binaphthalen-2-yl)triphenylamine (abbreviation: BBAαNβNB-03), 4,4'-diphenyl-4''-(7-phenyl)naphthalen-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4,4'-diphenyl-4''-(6;2'-binaphthalen-2-yl)triphenylamine (abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-(7;2'-binaphthalen-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diphenyl-4''-(4;2'-binaphthalen-1-yl)triphenylamine (abbreviation: BBAβNαNB), 4,4'-diphenyl-4''-(5;2'-binaphthalen-1-yl)triphenylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenyl)-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB), 4-(3-biphenyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: mTPBiAβNBi), 4-(4-biphenyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: TPBiAβNBi), 4-phenyl-4'-(1-naphthyl)triphenylamine (abbreviation: αNBA1BP), 4,4'-bis(1-naphthyl)triphenylamine (abbreviation: αNBB1BP), 4,4'-diphenyl-4''-[4'-(carbazol-9-yl)biphenyl-4-yl]triphenylamine (abbreviation: YGTBi1BP), 4'-[4-(3-phenyl-9H-carbazol-9-yl)phenyl]tris(biphenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carbazol-9-yl)biphenyl-4-yl]-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBNBSF), N,N-bis(biphenyl-4-yl)-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: BBASF), N,N-bis(biphenyl-4-yl)-9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: BBASF(4)), N-(biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: oFBiSF), N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)dibenzofuran-4-amine (abbreviation: FrBiF), N-[4-(1-naphthyl)phenyl]-N-[3-(6-phenyldibenzofuran-4-yl)phenyl]-1-naphthylamine (abbreviation: mPDBfBNBN), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine (abbreviation: BPAFLBi), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-bis(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF), N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF), N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluorene-4-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-Spirobi-9H-fluorene-3-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluorene-2-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluorene-1-amine, 9-[3-(triphenylsilyl)phenyl]-3,9'-bi-9H-carbazole (abbreviation: PSiCzCz), 9'-phenyl-9'H-9,3':6',9"-tricarbazole (abbreviation: PSiCzGI), etc.

[0191] In addition, as a substance having hole-transporting properties, as other aromatic amine compounds, N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), 4,4'-bis(N-{4-[N'-(3-methylphenyl)-N'-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), etc. can also be used.

[0192] By forming the hole injection layer 111, the hole injection property can be improved, and thus a light-emitting device with a low driving voltage can be obtained.

[0193] In addition, among substances having acceptor properties, organic compounds having acceptor properties can be easily formed by evaporation deposition, so they are materials that are easy to use.

[0194] The hole transport layer 112 is formed by including a substance having hole-transporting properties. As a substance having hole-transporting properties, it preferably has a hole mobility of 1×10 -6 cm 2 / Vs or more.

[0195] Examples of the hole-transporting material described above include compounds having an aromatic amine skeleton such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviation: TPD), N,N'-bis(9,9'-spirobi[9H-fluorene]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-bis(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF);1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-bis(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 3,3'-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP), 9,9'-bis(biphenyl-4-yl)-3,3'-bi-9H-carbazole (abbreviation: BisBPCz), 9,9'-bis(biphenyl-3-yl)-3,3'-bi-9H-carbazole (abbreviation: BismBPCz), 9-(biphenyl-3-yl)-9'-(biphenyl-4-yl)-9H,9'H-3,3'-bicarbazole (abbreviation: mBPCCBP), 9-(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: βNCCP), 9-(3-biphenyl)-9'-(2-naphthyl)-3,3'-bi-9H-carbazole (abbreviation: βNCCmBP), 9-(4-biphenyl)-9'-(2-naphthyl)-3,3'-bi-9H-carbazole (abbreviation: βNCCBP), 9,9'-di-2-naphthyl-3,3'-9H,9'H-bicarbazole (abbreviation: BisβNCz), 9-(2-naphthyl)-9'-[1,1':4',1''-terphenyl]-3-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':3',1''-terphenyl]-3-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':3',1''-terphenyl]-5'-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':4',1''-terphenyl]-4-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':3',1''-terphenyl]-4-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole, 9-phenyl-9'-(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole (abbreviation: PCCzTp), 9,9'-bis(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole, 9-(4-biphenyl)-9'-(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole, 9-(triphenylene-2-yl)-9'-[1,1':3',1''-terphenyl]-4-yl-3,3'-9H,9'H-bicarbazole, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluoren-1-amine, 9-[3-(triphenylsilyl)phenyl]-3,9'-bi-9H-carbazole (abbreviation: PSiCzCz) and other compounds with a carbazole backbone;4,4',4''-(benzene-1,3,5-triyl)tris(dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV) and other compounds having a thiophene skeleton; and 4,4',4''-(benzene-1,3,5-triyl)tris(dibenzofuran) (abbreviation: DBF3P-II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II) and other compounds having a furan skeleton. Among them, compounds having an aromatic amine skeleton and compounds having a carbazole skeleton have high reliability and excellent hole transport properties and contribute to reducing the driving voltage, so they are preferred. In addition, an organic compound cited as a hole-transporting substance used as a composite material for the hole injection layer 111 can also be appropriately used as a material for constituting the hole transport layer 112.;

[0196] The hole transport layer 112 may also have a stacked structure. Among them, in the layer in contact with the light-emitting layer 113 (electron blocking layer), a deuterated organic compound is preferably used. As a material preferably used for the electron blocking layer, the same materials as the second organic compound described later can be cited. When a deuterated material is used for the electron blocking layer, even when the electron blocking layer in contact with the light-emitting layer is excited, deterioration of the organic compound used for the electron blocking layer can be suppressed and deterioration of the light-emitting device can be suppressed, thereby realizing a highly reliable light-emitting device.

[0197] The light-emitting center substance contained in the light-emitting layer 113 is preferably a phosphorescent substance or a substance exhibiting thermally activated delayed fluorescence (TADF).

[0198] When a phosphorescent substance is used as the light-emitting substance in the light-emitting layer 113, as the phosphorescent substance, for example, the following materials can be cited.

[0199] Tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN2]phenyl-κC}iridium(III) (abbreviation: [Ir(mpptz-dmp) 3 )、Tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazole)iridium(III) (abbreviation: [Ir(Mptz) 3 ) and other organometallic iridium complexes having a 4H-triazole skeleton; Tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazole]iridium(III) (abbreviation: [Ir(Mptz1-mp)3 ) tris(1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazole)iridium(III) (abbreviation: [Ir(Prptz1-Me) 3 ) and other organometallic iridium complexes with a 1H-triazole skeleton; fac-tris[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation: [Ir(iPrpim) 3 ), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: [Ir(dmpimpt-Me) 3 ), tris(2-{1-[2,6-bis(1-methylethyl)phenyl]-1H-imidazol-2-yl-κN3}-4-cyanophenyl-κC)iridium(III) (abbreviation: CNImIr) and other organometallic iridium complexes with an imidazole skeleton; tris[(6-tert-butyl-3-phenyl-2H-imidazo[4,5-b]pyrazin-1-yl-κC2)phenyl-κC]iridium(III) (abbreviation: [Ir(cb) 3 ), and other organometallic complexes with a benzimidazolylidene skeleton; and bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2 ']iridium(III) tetra(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2 ']iridium(III) picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinato-N,C 2 '}iridium(III) picolinate (abbreviation: [Ir(CF 3 ppy) 2 (pic)]), bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2 ']iridium(III) acetylacetonate (abbreviation: FIrracac) and other organometallic iridium complexes with phenylpyridine derivatives having an electron-withdrawing group as ligands; (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazol-1-yl-2-ylidene-κC2]phenoxy-κC2}-9-(4-tert-butyl-2-pyridyl-κN)carbazole-2,1-diyl-κC1)platinum(II) (abbreviation: PtON-TBBI) and other platinum complexes; etc. The above substances are compounds that emit blue phosphorescence and are compounds having a luminescence peak in the wavelength region of 450 nm to 520 nm. In addition, compounds obtained by substituting part of the hydrogen in the above compounds with deuterium can also be used.

[0200] In addition, examples include tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm) 3 )], tris(4-tert-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm) 3 )], (acetylacetonato)bis(6-methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm) 2 (acac)]), (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm) 2 (acac)]), (acetylacetonato)bis[6-(2-norbornanyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(nbppm) 2 (acac)]), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(mpmppm) 2 (acac)]), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm) 2 (acac)]) and other organometallic iridium complexes with a pyrimidine skeleton; (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-Me) 2 (acac)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-iPr) 2 (acac)]) and other organometallic iridium complexes with a pyrazine skeleton; tris(2-phenylpyridinato-N,C 2’ )iridium(III) (abbreviation: [Ir(ppy) 3 ), bis(2-phenylpyridinato-N,C 2’ )iridium(III) acetylacetonate (abbreviation: [Ir(ppy) 2 (acac)]), bis(benzo[h]quinolinato)iridium(III) acetylacetonate (abbreviation: [Ir(bzq) 2 (acac)]), tris(benzo[h]quinolinato)iridium(III) (abbreviation: [Ir(bzq) 3 ), tris(2-phenylquinolinato-N,C 2’ )]iridium(III) (abbreviation: [Ir(pq) 3 ), bis(2-phenylquinolinato-N,C 2’ )iridium(III) acetylacetonate (abbreviation: [Ir(pq) 2 (acac)]), [2-d 3-Methyl-8-(2-pyridinyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(5-d 3 -Methyl-2-pyridinyl-κN 2 )phenyl-κC]iridium(III) (abbreviation: Ir(5mppy-d 3 )) 2 (mbfpypy-d 3 ))、{2-(Methyl-d3)-8-[4-(1-methylethyl-1-d)-2-pyridinyl-κN]benzofuro[2,3-b]pyridin-7-yl-κC}bis{5-(methyl-d 3 )-2-[5-(methyl-d 3 )-2-pyridinyl-κN]phenyl-κC}iridium(III) (abbreviation: Ir(5mtpy-d 6 )) 2 (mbfpypy-iPr-d 4 ))、[2-d3-Methyl-(2-pyridinyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy) 2 (mbfpypy-d 3 ))、[2-(4-Methyl-5-phenyl-2-pyridinyl-κN)phenyl-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy) 2 (mdppy))、[2-(4-d 3 -Methyl-5-phenyl-2-pyridinyl-κN2)phenyl-κC]bis[2-(5-d 3 -Methyl-2-pyridinyl-κN2)phenyl-κC]iridium(III) (abbreviation: [Ir(5mppy-d3) 2 (mdppy-d 3 )、[2-d3-Methyl-(2-pyridinyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: [Ir(ppy) 2 (mbfpypy)])、[2-(4-Methyl-5-phenyl-2-pyridinyl-κN)phenyl-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium (abbreviation: [Ir(ppy) 2 (mdppy)])、Tris{2-[5-(methyl-d3)-4-phenyl-2-pyridinyl-κN]phenyl-κC}iridium(III) (abbreviation: Ir(5m4dppy-d 3 )) 3Organic metal iridium complexes having a pyridine skeleton; and rare earth metal complexes such as tris(acetylacetonato)(monophenanthroline) terbium(III) (abbreviation: [Tb(acac) 3 (Phen)]). The above substances are mainly compounds that exhibit green phosphorescence and have a luminescence peak in the wavelength range of 500 nm to 600 nm. In addition, since the organic metal iridium complex having a pyrimidine skeleton has particularly excellent reliability or luminescence efficiency, it is particularly preferred. In addition, compounds obtained by substituting part of the hydrogen in the above compounds with deuterium can also be used.

[0201] In addition, examples include: bis(4,6-bis(3-methylphenyl)pyrimidinato)(diisobutyrylmethanato)iridium(III) (abbreviation: [Ir(5mdppm) 2 (dibm)]), bis(4,6-bis(3-methylphenyl)pyrimidinato)(dineopentanoylmethanato)iridium(III) (abbreviation: [Ir(5mdppm) 2 (dpm)]), bis(4,6-di(naphthalen-1-yl)pyrimidinato)(dineopentanoylmethanato)iridium(III) (abbreviation: [Ir(d1npm) 2 (dpm)]) and other organic metal iridium complexes having a pyrimidine skeleton; bis(2,3,5-triphenylpyrazinato)(acetylacetonato)iridium(III) (abbreviation: [Ir(tppr) 2 (acac)]), bis(2,3,5-triphenylpyrazinato)(dineopentanoylmethanato)iridium(III) (abbreviation: [Ir(tppr) 2 (dpm)]) and other organic metal iridium complexes having a pyrazine skeleton; tris(1-phenylisoquinoline-N,C 2 )iridium(III) (abbreviation: [Ir(piq) 2’ )], bis(1-phenylisoquinoline-N,C 3 )iridium(III) acetylacetonate (abbreviation: [Ir(piq) 2’ ) (abbreviation: [Ir(piq) 2(acac)), (3,7 - diethyl - 4,6 - nonanedionato - κO4,κO6)bis[2,4 - dimethyl - 6 - [7 - (1 - methylethyl)-1 - isoquinolinyl - κN]phenyl - κC]iridium(III), (3,7 - diethyl - 4,6 - nonanedionato - κO4,κO6)bis[2,4 - dimethyl - 6 - [5 - (1 - methylethyl)-2 - quinolinyl - κN]phenyl - κC]iridium(III) and other organometallic iridium complexes having a pyridine skeleton; platinum complexes such as 2,3,7,8,12,13,17,18 - octaethyl - 21H,23H - porphyrin platinum(II) (abbreviation: PtOEP); and tris(1,3 - diphenyl - 1,3 - propanedionato)(monophenanthroline)europium(III) (abbreviation: [Eu(DBM) 3 (Phen)]), tris[1 - (2 - thenoyl)-3,3,3 - trifluoroacetone](monophenanthroline)europium(III) (abbreviation: [Eu(TTA) 3 (Phen)]) and other rare earth metal complexes. The above substances are compounds that exhibit red phosphorescence and have a luminescence peak in the wavelength region of 600 nm to 700 nm. In addition, organometallic iridium complexes having a pyrazine skeleton can obtain red luminescence with good chromaticity. In addition, compounds obtained by substituting part of the hydrogen in the above compounds with hydrogen can also be used.

[0202] In addition, when a deuterated compound is used as the luminescent center material in one embodiment of the present invention, the luminescence efficiency is improved. Therefore, the luminescent center material is preferably a deuterated material.

[0203] In addition to the above phosphorescent compounds, known phosphorescent compounds can also be selected and used.

[0204] Fullerenes and their derivatives, acridine and its derivatives, eosin derivatives, etc. can be used as TADF materials. In addition, metal - containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In) or palladium (Pd) etc. can also be mentioned. As the metal - containing porphyrin, for example, protoporphyrin - tin fluoride complex (SnF 2 (Proto IX)), mesoporphyrin - tin fluoride complex (SnF 2 (Meso IX)), hematoporphyrin - tin fluoride complex (SnF 2 (Hemato IX)), coproporphyrin tetramethyl ester - tin fluoride complex (SnF 2 (Copro III - 4Me), octaethylporphyrin - tin fluoride complex (SnF 2 (OEP)), protoporphyrin - tin fluoride complex (SnF2 (Etio I)) and octaethylporphyrin-platinum chloride complex (PtCl 2 OEP), etc.

[0205] [Chemical formula 2]

[0206]

[0207] In addition, 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ), 9-(4,6-diphenyl-1,3,5-triazin-2-yl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCCzTzn), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 2-[4-(10H-phenoxazin-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthen-9-one (abbreviation: ACRXTN), bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracene]-10'-one (abbreviation: ACRSA), etc., which are heterocyclic compounds having one or both of a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring, can also be used. The heterocyclic compound has a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring, and has high electron transportability and hole transportability, so it is preferred. Among them, in the skeleton having a π-electron-deficient heteroaromatic ring, the pyridine skeleton, the diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton) and the triazine skeleton are stable and have high reliability, so they are preferred. In particular, the benzofuranopyrimidine skeleton, the benzothiophenopyrimidine skeleton, the benzofuranopyrazine skeleton and the benzothiophenopyrazine skeleton have high acceptability and high reliability, so they are preferred. In addition, in the skeleton having a π-electron-rich heteroaromatic ring, the acridine skeleton, the phenoxazine skeleton, the phenothiazine skeleton, the furan skeleton, the thiophene skeleton and the pyrrole skeleton are stable and have high reliability, so it is preferred to have at least one of the above skeletons. In addition, as the furan skeleton, a dibenzofuran skeleton is preferably used, and as the thiophene skeleton, a dibenzothiophene skeleton is preferably used. As the pyrrole skeleton, an indole skeleton, a carbazole skeleton, an indolocarbazole skeleton, a bicarbazole skeleton, and a 3-(9-phenyl-9H-carbazol-3-yl)-9H-carbazole skeleton are particularly preferably used. In a substance in which a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring are directly bonded, both the electron-donating property of the π-electron-rich heteroaromatic ring and the electron-accepting property of the π-electron-deficient heteroaromatic ring are high, and the lowest singlet excitation energy level (S 1 energy level) and T 1The energy difference between the energy levels becomes smaller, and thermally activated delayed fluorescence can be efficiently obtained, so it is particularly preferred. Note that an aromatic ring bonded with an electron-withdrawing group such as a cyano group can also be used instead of the π-deficient heteroaromatic ring. In addition, as the π-rich electron skeleton, an aromatic amine skeleton, a phenazine skeleton, etc. can be used. In addition, as the π-deficient electron skeleton, an oxanthrene skeleton, a thioxanthene dioxide skeleton, an oxadiazole skeleton, a triazole skeleton, an imidazole skeleton, an anthraquinone skeleton, a boron-containing skeleton such as phenylborane or boranthrene, an aromatic ring or heteroaromatic ring having a nitrile group or a cyano group such as benzonitrile or cyanobenzene, a carbonyl skeleton such as benzophenone, a phosphine oxide skeleton, a sulfone skeleton, etc. can be used. Thus, at least one of the π-deficient heteroaromatic ring and the π-rich heteroaromatic ring can be replaced with a π-deficient electron skeleton and a π-rich electron skeleton. In addition, a compound obtained by substituting part of the hydrogen in the above compound with hydrogen can also be used.

[0208] [Chemical formula 3]

[0209]

[0210] TADF materials refer to S 1 energy levels and T 1 materials with a relatively small energy difference between energy levels and having the function of converting triplet excitation energy into singlet excitation energy through reverse intersystem crossing. Therefore, triplet excitation energy can be up-converted into singlet excitation energy (reverse intersystem crossing) by a small amount of thermal energy and singlet excited states can be efficiently generated. In addition, triplet excitation energy can be converted into luminescence.

[0211] An exciplex formed by two substances in the excited state has the function of a TADF material that can convert triplet excitation energy into singlet excitation energy due to the extremely small energy difference between the S 1 energy levels and the T 1 energy levels.

[0212] Note that as an index of the T 1 energy level, a phosphorescence spectrum observed at low temperature (for example, 77K to 10K) can be used. For TADF materials, preferably, when the wavelength energy of the extrapolated line obtained by drawing a tangent at the tail on the short wavelength side of the fluorescence spectrum is the S 1 energy level and the wavelength energy of the extrapolated line obtained by drawing a tangent at the tail on the short wavelength side of the phosphorescence spectrum is the T 1 energy level, the difference between S 1 and T 1 is 0.3 eV or less, more preferably 0.2 eV or less.

[0213] In addition, when a TADF material is used as a luminescent substance, the S 1The energy level is preferably higher than that of S of the TADF material. 1 In addition, the T energy level of the energy donor is preferably higher than that of T of the TADF material. 1 1 energy level.

[0214] As the organic compound that can be used as the first organic compound in the light-emitting layer 113, an organic compound containing deuterium and having an electron mobility of 1×10 -7 cm 2 / Vs or more, preferably 1×10 -6 cm 2 / Vs or more and having electron-transporting properties is preferably used.

[0215] As the first organic compound, an organic compound having a π-deficient heteroaromatic ring is preferably used. As the organic compound having a π-deficient heteroaromatic ring skeleton, for example, an organic compound containing a heteroaromatic ring having a triazole skeleton, an organic compound containing a heteroaromatic ring having a pyridine skeleton, an organic compound containing a heteroaromatic ring having a diazine skeleton, and an organic compound containing a heteroaromatic ring having a triazine skeleton can be cited.

[0216] Among them, an organic compound containing a heteroaromatic ring having a diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), an organic compound containing a heteroaromatic ring having a pyridine skeleton, or an organic compound containing a heteroaromatic ring having a triazine skeleton has good reliability, so it is preferred. In particular, an organic compound containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton and an organic compound containing a heteroaromatic ring having a triazine skeleton have high electron-transporting properties, which helps to reduce the driving voltage. In addition, a benzofuranopyrimidine skeleton, a benzothiophenopyrimidine skeleton, a benzofuranopyrazine skeleton, and a benzothiophenopyrazine skeleton have high acceptability and high reliability, so they are preferred.

[0217] As the organic compound having a π-electron-deficient heteroaromatic ring skeleton that can be used as the first organic compound, for example, the following deuterated organic compounds are preferably used. Examples thereof include 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 2,2',2"-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzo[1-nitrophenyl]-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), organic compounds having an azole skeleton, such as 1,4-di(5-methylbenzoxazol-2-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviated as mDBTBIm-II), 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (abbreviated as BzOs); 3,5-bis[3-(9H-carbazole-9-yl)phenyl]pyridine (abbreviated as 35DCzPPy), 1,3,5-tris[3-(3-pyridyl)phenyl]benzene (abbreviated as TmPyPB), bathophenanthroline (abbreviated as Bphen), bathocuproin (abbreviated as BCP), 2,9-di(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviated as NBphen), 2,2'-(1 Organic compounds containing a heteroaromatic ring having a pyridine skeleton, such as 2-[3-(dibenzothiophen-4-yl)phenyl]-1,10-phenanthroline (abbreviated as: mPPhen2P), 2-[3-(2-triphenylene)phenyl]-1,10-phenanthroline (abbreviated as: mTpPPhen), 2-phenyl-9-(2-triphenylene)-1,10-phenanthroline (abbreviated as: Ph-TpPhen), 2-[4-(9-phenanthrenyl)-1-naphthyl]-1,10-phenanthroline (abbreviated as: PnNPhen), and 2-[4-(2-triphenylene)phenyl]-1,10-phenanthroline (abbreviated as: pTpPPhen); 2-[3-(dibenzothiophen-4-yl)phenyl]-1,10-phenanthroline (abbreviated as: mTpPPhen), 2-phenyl-9-(2-triphenylene)-1,10-phenanthroline (abbreviated as: Ph-TpPhen), 1-(4-(6-phenyl-9H-carbazole-3-yl)-3,1'-biphenyl-1-yl)dibenzo[f,h]quinoxaline (abbreviated as 2mCzBPDBq), 2-[4'-(9-phenyl-9H-carbazole-3-yl)-3,1'-biphenyl-1-yl]dibenzo[f,h]quinoxaline (abbreviated as 2mpPCBPDBq), 2-[4-(3,6-diphenyl-9H-carbazole-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as 2mpPCBPDBq), 2-[3'-(9H-carbazole-9-yl)biphenyl-3-yl] ...3'-(9H-carbazole-9-yl)biphenyl]dibenzo[f,h]quinoxaline (abbreviated as 2mCzBPDBq), 2-[3'-(9H-h]Quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(Dibenzo[b]thiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), 6-[3-(Dibenzo[b]thiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 9-[3’-(Dibenzo[b]thiophen-4-yl)biphenyl-3-yl]naphtho[1’,2’:4,5]furo[2,3-b]pyrazine (abbreviation: 9mDBtBPNfpr), 9-[3’-(Dibenzo[b]thiophen-4-yl)biphenyl-4-yl]naphtho[1’,2’:4,5]furo[2,3-b]pyrazine (abbreviation: 9pmDBtBPNfpr), 4,6-Bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-Bis[3-(dibenzo[b]thiophen-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6-Bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm), 9,9’-[Pyrimidine-4,6-diylbis(biphenyl-3,3’-diyl)]bis(9H-carbazole) (abbreviation: 4,6mCzBP2Pm), 8-(Biphenyl-4-yl)-4-[3-(dibenzo[b]thiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8BP-4mDBtPBfpm), 3,8-Bis[3-(dibenzo[b]thiophen-4-yl)phenyl]benzofuro[2,3-b]pyrazine (abbreviation: 3,8mDBtP2Bfpr), 4,8-Bis[3-(dibenzo[b]thiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 4,8mDBtP2Bfpm), 8-[3’-(Dibenzo[b]thiophen-4-yl)(biphenyl-3-yl)]naphtho[1’,2’:4,5]furo[3,2-d]pyrimidine (abbreviation: 8mDBtBPNfpm), 8-[(2,2’-Binaphthalen)-6-yl]-4-[3-(dibenzo[b]thiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8(βN2)-4mDBtPBfpm), 2,2’-(Pyridine-2,6-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 2,6(P-Bqn)2Py), 2,2’-(Pyridine-2,6-diyl)bis{4-[4-(naphthalen-2-yl)phenyl]-6-phenylpyrimidine} (abbreviation: 2,6(NP-PPm)2Py), 6-(Biphenyl-3-yl)-4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), 2,6-Bis(4-naphthalen-1-ylphenyl)-4-[4-(pyridin-3-yl)phenyl]pyrimidine (abbreviation: 2,4NP-6PyPPm), 4-[3,5-Bis(9H-carbazol-9-yl)phenyl]-2-phenyl-6-(biphenyl-4-yl)pyrimidine (abbreviation: 6BP-4Cz2PPm), 7-[4-(9-phenyl-9H-carbazol-2-yl)quinazolin-2-yl]-7H-dibenzo[c,g]carbazole (abbreviation: PC-cgDBCzQz), 8-(p-terphenyl-3-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8mpTP-4mDBtPBfpm) and other organic compounds with a diazine backbone; 2-(biphenyl-4-yl)-4-phenyl-6-(9,9'-spirobi[9H-fluorene]-2-yl)-1,3,5-triazine (abbreviation: BP-SFTzn), 2-{3-[3-(benzo[b]naphtho[1,2-d]furan-8-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mBnfBPTzn), 2-{3-[3-(benzo[b]naphtho[1,2-d]furan-6-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mBnfBPTzn-02), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 9-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTzn-02), 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFBPTzn), 5-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]carbazole (abbreviation: mINc(II)PTzn), 2-{3-[3-(dibenzothiophen-4-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mDBtBPTzn), 2,4,6-tris[3'-(pyridin-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviation: TmPPPyTz), 2-[3-(2,6-dimethyl-3-pyridyl)-5-(9-phenanthryl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mPn-mDMePyPTzn), 2-[3'-(triphenylene-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mTpBPTzn), 3-[9-(4,6-diphenyl-1,3,5-triazin-2-yl)-2-dibenzofuranyl]-9-phenyl-9H-carbazole (abbreviation: PCDBfTzn), 2-[4-(2-naphthyl)phenyl]-4-phenyl-6-spiro[9H-fluorene-9,9'-[9H]xanthen]-4-yl-1,3,5-triazine (abbreviation: βNP-SFx(4)Tzn), 9,9'-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazin-2,4-diyl}bis(9H-carbazole) (abbreviation: SiTrzCz2), 2-phenyl-4,6-bis[3-(triphenylsilyl)phenyl]-1,3,5-triazine (abbreviation: mSiTrz), 11-[4-(biphenyl-4-yl)-6-phenyl-1,3,5-triazin-2-yl]-11,12-dihydro-12-(biphenyl-3-yl)indolo[2,3-a]carbazole (abbreviation: BP-mBPIcz(II)Tzn), 11-[4-(biphenyl-4-yl)-6-phenyl-1,3,5-triazin-2-yl]-11,12-dihydro-12-phenylindolo[2,3-a]carbazole (abbreviation: BP-Icz(II)Tzn), 3-{3-[9-(4,6-diphenyl-1,3,5-triazin-2-yl)-2-dibenzofuranyl]phenyl}-9-phenyl-9H-carbazole (abbreviation: mPCPDBfTzn), 9,9'-[6-(biphenyl-4-yl)-2-phenyl-1,3,5-triazin-4,3''-diyl]bis(9H-carbazole) (abbreviation: Cz-pmCzBPTzn), 2-(biphenyl-3-yl)-4-phenyl-6-{8-[(1,1':4',1''-terphenyl)-4-yl]-1-dibenzofuranyl}-1,3,5-triazine (abbreviation: mBP-TPDBfTzn), 3-phenyl-9-[4-phenyl-6-(9-phenyl-3-dibenzofuranyl)-1,3,5-triazin-2-yl]-9H-carbazole (abbreviation: PDBf-PCzTzn), 9-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)-2-dibenzothiophenyl]-2-phenyl-9H-carbazole (abbreviation: PCzDBtTzn), etc., organic compounds containing a heteroaromatic ring having a triazine skeleton. In addition, an organic compound containing a heteroaromatic ring having a diazine skeleton, an organic compound containing a heteroaromatic ring having a pyridine skeleton, or an organic compound containing a heteroaromatic ring having a triazine skeleton has high reliability and is therefore preferred. In particular, an organic compound containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton and an organic compound containing a heteroaromatic ring having a triazine skeleton have high electron transportability and contribute to reducing the driving voltage.,

[0218] As a hole-transporting material that can be used as the second organic compound in the light-emitting layer 113, an organic compound containing deuterium and having an amine skeleton or a π-electron-rich heteroaromatic ring skeleton is preferably used. As the π-electron-rich heteroaromatic ring, a fused aromatic ring containing at least any one of an acridine skeleton, a phenoxazine skeleton, a phenothiazine skeleton, a furan skeleton, a thiophene skeleton, and a pyrrole skeleton is preferred, and specifically, a carbazole ring, a dibenzothiophene ring, or a ring in which these rings are further fused with an aromatic ring or a heteroaromatic ring is preferred.

[0219] Such a hole-transporting material preferably has any one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton. In particular, it can be an aromatic amine having a substituent including a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine including a naphthalene ring, or an aromatic monoamine in which 9-fluorenyl is bonded to the nitrogen of the amine through an arylene group. Note that when these hole-transporting materials are organic compounds including N,N-bis(4-biphenyl)amino, a light-emitting device with a long lifetime can be manufactured, so they are preferred.

[0220] As the above-mentioned organic compound, for example, preferably used are the deuterated organic compounds exemplified below. Examples include: 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviation: TPD), N,N'-bis(9,9'-spirobi[9H-fluorene]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-bis(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluorene-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF) and other compounds having an aromatic amine skeleton; 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-bis(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 3,3'-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP), 3,9-bis(9-phenyl-9H-carbazol-3-yl)-9H-carbazole (abbreviation: PCCzPC), 9-(biphenyl-4-yl)-9'-phenyl-3,3'-bi-9H-carbazole (abbreviation: PCCzBP), 9,9'-bis(biphenyl-4-yl)-3,3'-bi-9H-carbazole (abbreviation: BisBPCz), 9,9'-bis(biphenyl-3-yl)-3,3'-bi-9H-carbazole (abbreviation: BismBPCz), 9-(biphenyl-3-yl)-9'-(biphenyl-4-yl)-9H,9'H-3,3'-bicarbazole (abbreviation: mBPCCBP), 9-(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: βNCCP), 9-(3-biphenyl)-9'-(2-naphthyl)-3,3'-bi-9H-carbazole (abbreviation: βNCCmBP), 9-(4-biphenyl)-9'-(2-naphthyl)-3,3'-bi-9H-carbazole (abbreviation: βNCCBP), 9,9'-Di-2-naphthyl-3,3'-9H,9'H-bicarbazole (abbreviation: BisβNCz), 9-(2-naphthyl)-9'-[1,1':4',1''-terphenyl]-3-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':3',1''-terphenyl]-3-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':3',1''-terphenyl]-5'-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':4',1''-terphenyl]-4-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':3',1''-terphenyl]-4-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole, 9-phenyl-9'-(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole (abbreviation: PCCzTp), 9,9'-bis(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole, 9-(4-biphenyl)-9'-(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole, 9-(triphenylene-2-yl)-9'-[1,1':3',1''-terphenyl]-4-yl-3,3'-9H,9'H-bicarbazole, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluorene-1-amine, 9-[3-(triphenylsilyl)phenyl]-3,9'-bi-9H-carbazole (abbreviation: PSiCzCz), 9'-phenyl-9'H-9,3':6',9''-tricarbazole (abbreviation: PSiCzGI) and other compounds with a carbazole skeleton; 4,4',4''-(benzene-1,3,5-triyl)tris(dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV) and other compounds with a thiophene skeleton; and 4,4',4''-(benzene-1,3,5-triyl)tris(dibenzofuran) (abbreviation: DBF3P-II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II) and other compounds with a furan skeleton. Among them, the compounds with an aromatic amine skeleton or a carbazole skeleton have high reliability and high hole transportability and contribute to reducing the driving voltage, so they are preferred.

[0221] In a light-emitting device according to one embodiment of the present invention, at least one light-emitting layer has the structure disclosed in Embodiment 1. In the case where the light-emitting device includes a plurality of light-emitting layers, a fluorescent light-emitting substance may also be used as a light-emitting center substance in other light-emitting layers.

[0222] Examples of materials that can be used when a fluorescent light-emitting substance is used as a light-emitting center substance are as follows. Note that other fluorescent light-emitting substances may also be used.

[0223] Examples include 5,6-bis[4-(10-phenyl-9-anthryl)phenyl]-2,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-anthryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenyldistyrene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra-tert-butylperylene (abbreviation: TBP), 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), N,N''-(2-tert-butylanthracene-9,10-diyl-di-4,1-phenylene)bis(N,N',N'-triphenyl-1,4-phenylenediamine) (abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), N,N,N',N',N'',N'',N''',N''' -octaphenyldibenzo[g,p] (chrysene)-2,7,10,15-tetraamine (abbreviation: DBC1), Coumarin 30, N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracen-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracen-9-amine (abbreviation: DPhAPhA), Coumarin 545T, N,N'-diphenylquinacridone (abbreviation: DPQd), Rubrene, 5,12-bis(biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]vinyl}-6-methyl-4H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N',N'-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,10-diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]vinyl}-4H-pyran-4-ylidene)propanedinitrile (abbreviation: BisDCM), 2-{2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), N,N'-diphenyl-N,N'-(1,6-pyrene-diyl)bis[(6-phenylbenzo[b]naphtho[1,2-d]furan)-8-amine (abbreviation: 1,6BnfAPrn-03), N,N'-diphenyl-N,N'-bis(9-phenyl-9H-carbazol-2-yl)naphtho[2,3-b;6,7-b']bisbenzofuran-3,10-diamine (abbreviation: 3,10PCA2Nbf(IV)-02), 3,10-bis[N-(dibenzofuran-3-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10FrA2Nbf(IV)-02), etc. In particular, fused aromatic diamine compounds represented by pyrene diamine compounds such as 1,6FLPAPrn, 1,6mMemFLPAPrn, 1,6BnfAPrn-03, etc. have high hole trapping properties, high luminous efficiency and high reliability, so they are preferred.,

[0224] When a fluorescent light-emitting substance is used as the light-emitting center substance, as the host material, a material having a polyacene skeleton, especially an anthracene skeleton, is preferably used. By using a substance having an anthracene skeleton as the host material of the fluorescent light-emitting substance, a light-emitting layer with both high luminous efficiency and durability can be realized. Among the substances having an anthracene skeleton used as the host material, a substance having a diphenylanthracene skeleton (especially a 9,10-diphenylanthracene skeleton) is chemically stable, so it is preferred. In addition, when the host material has a carbazole skeleton, the hole injection / transport property is improved, so it is preferred. In the case of a benzocarbazole skeleton in which a benzene ring is fused to carbazole, its HOMO energy level is about 0.1 eV higher than that of the case having a carbazole skeleton, and holes are easily injected, so it is more preferred. In particular, when the host material has a dibenzocarbazole skeleton, its HOMO energy level is about 0.1 eV higher than that of the case having a carbazole skeleton, and not only are holes easily injected, but also the hole transport property and heat resistance are improved, so it is preferred. Therefore, a substance further preferably used as the host material is a substance having a 9,10-diphenylanthracene skeleton and a carbazole skeleton (or a benzocarbazole skeleton or a dibenzocarbazole skeleton). Note that from the above viewpoint of hole injection / transport property, a benzofluorene skeleton or a dibenzofluorene skeleton can also be used instead of the carbazole skeleton.,

[0225] Examples of such substances include 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA), 3-[4-(1-naphthyl)phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: CzPA), 7-[4-(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgDBCzPA), 6-[3-(9,10-diphenyl-2-anthryl)phenyl]-benzo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl-10-[4-(9-phenyl-9H-fluoren-9-yl)-biphenyl-4'-yl]anthracene (abbreviation: FLPPA), 9-(1-naphthyl)-10-[4-(2-naphthyl)phenyl]anthracene (abbreviation: αN-βNPAnth), 9-(1-naphthyl)-10-(2-naphthyl)anthracene (abbreviation: α,βADN), 2-(10-phenylanthracen-9-yl)dibenzofuran, 2-(10-phenyl-9-anthryl)-benzo[b]naphtho[2,3-d]furan (abbreviation: Bnf(II)PhA), 9-(2-naphthyl)-10-[3-(2-naphthyl)phenyl]anthracene (abbreviation: βN-mβNPAnth), 1-{4-[10-(biphenyl-4-yl)-9-anthryl]phenyl}-2-ethyl-1H-benzimidazole (abbreviation: EtBImPBPhA), etc. In particular, CzPA, cgDBCzPA, 2mBnfPPA, and PCzPA exhibit very good characteristics and are therefore preferred.

[0226] In addition, by mixing the first organic compound and the second organic compound, the transport property of the light-emitting layer 113 can be easily adjusted, and the recombination region can also be easily controlled. The weight ratio of the contents of the first organic compound and the second organic compound can be second organic compound : first organic compound = 1:19 to 19:1.

[0227] Furthermore, the first organic compound and the second organic compound form an exciplex. By selecting the mixed materials in such a way that an exciplex that emits light overlapping the absorption band on the lowest energy side of the light-emitting substance is formed, the energy transfer can be made smooth, and thus efficient light emission can be obtained, so it is preferred. In addition, by adopting this structure, the driving voltage can be reduced, so it is preferred.

[0228] Regarding the combination of materials for efficiently forming exciplexes, the HOMO energy level of the second organic compound is preferably higher than that of the first organic compound. In addition, the LUMO energy level of the second organic compound is preferably higher than that of the first organic compound. Note that the LUMO energy level and HOMO energy level of the material can be obtained from the electrochemical characteristics (reduction potential and oxidation potential) of the material measured by cyclic voltammetry (CV).

[0229] Note that the formation of exciplexes can be confirmed, for example, by comparing the emission spectra of the second organic compound, the emission spectra of the first organic compound, and the emission spectra of the mixed film formed by mixing these materials. When it is observed that the emission spectrum of the mixed film shifts to the longer wavelength side (or has a new peak on the longer wavelength side) compared to the emission spectra of the respective materials, it indicates the formation of exciplexes. Or, by comparing the transient photoluminescence (PL) of the second organic compound, the transient PL of the first organic compound, and the transient PL of the mixed film formed by mixing these materials, when it is observed that the transient PL lifetime of the mixed film has a longer lifetime component or a larger ratio of the delayed component compared to the transient PL lifetimes of the respective materials, it indicates the formation of exciplexes. In addition, the above transient PL can be referred to as transient electroluminescence (EL). In other words, by comparing the transient EL of the second organic compound, the transient EL of the first organic compound, and the transient EL of the mixed film of these materials, and observing the difference in transient response, the formation of exciplexes can be confirmed.

[0230] The electron transport layer 114 is a layer containing a substance having electron transport properties. As the substance having electron transport properties, it is preferably a substance having an electron mobility of 1×10 -7 cm 2 / Vs or more when the square root of the electric field strength [V / cm] is 600, and preferably 1×10 -6 cm 2 / Vs or more. In addition, as long as the substance has higher electron transport properties than hole transport properties, substances other than the above can be used. As the above organic compound, an organic compound containing a π-deficient heteroaromatic ring is preferably used. As the organic compound containing a π-deficient heteroaromatic ring, for example, an organic compound containing a heteroaromatic ring having a triazole skeleton, an organic compound containing a heteroaromatic ring having a pyridine skeleton, an organic compound containing a heteroaromatic ring having a diazine skeleton, and an organic compound containing a heteroaromatic ring having a triazine skeleton, any one or more of them are preferably used.

[0231] As a material having electron-transporting properties that can be used for the above-described electron transport layer 114, the same organic compounds as those exemplified as the organic compounds that can be used as the first organic compound by deuteration in the above-described light-emitting layer 113 can also be used. In addition, the material having electron-transporting properties that can be used for the electron transport layer 114 may not be deuterated.

[0232] Among the organic compounds exemplified as the organic compounds that can be used as the first organic compound by deuteration, organic compounds containing a heteroaromatic ring having a diazine skeleton, organic compounds containing a heteroaromatic ring having a pyridine skeleton, and organic compounds containing a heteroaromatic ring having a triazine skeleton have good reliability and are therefore preferred. In particular, organic compounds containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton and organic compounds containing a heteroaromatic ring having a triazine skeleton have high electron-transporting properties and contribute to reducing the driving voltage. In particular, organic compounds having a phenanthroline skeleton such as mTpPPhen, PnNPhen, and mPPhen2P are preferred, and organic compounds having a phenanthroline dimer structure such as mPPhen2P have excellent stability and are therefore more preferred.

[0233] Note that the electron transport layer 114 may also have a stacked structure. The layer in the electron transport layer 114 having a stacked structure that contacts the light-emitting layer 113 may also be used as a hole-blocking layer. When the electron transport layer in contact with the light-emitting layer is used as a hole-blocking layer, a material having a HOMO energy level lower than that of the material in the light-emitting layer 113 by 0.5 eV or more is preferably used.

[0234] As the electron injection layer 115, a layer containing an alkali metal or alkaline earth metal, a compound of an alkali metal or alkaline earth metal, a complex of an alkali metal or alkaline earth metal, or 1,1'-pyridine-2,6-diyl-bis(1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine) (abbreviation: hpp2Py) or the like may also be provided. As the electron injection layer 115, a layer containing the above-described substance in a layer composed of a material having electron-transporting properties may also be used.

[0235] In addition, a charge generation layer 116 may be provided instead of the electron injection layer 115 ( Figure 1B)。The charge generation layer 116 is a layer that can inject holes into the layer in contact with the cathode side of this layer and inject electrons into the layer in contact with the anode side of this layer by applying a potential. The charge generation layer 116 includes at least a P-type layer 117. The P-type layer 117 is preferably formed using the composite material that constitutes the hole injection layer 111 described above. In addition, the P-type layer 117 can also be formed by laminating a film containing an acceptor material and a film layer containing a hole transport material as materials constituting the composite material. By applying a potential to the P-type layer 117, electrons and holes are respectively injected into the electron transport layer 114 and the cathode, causing the light-emitting device to operate. In addition, the organic compound of one embodiment of the present invention is an organic compound with a low refractive index, and by using it for the P-type layer 117, a light-emitting device with good external quantum efficiency can be obtained.

[0236] In addition, in addition to including the P-type layer 117, the charge generation layer 116 preferably further includes either or both of an electron relay layer 118 and an electron injection buffer layer 119.

[0237] The electron relay layer 118 contains at least a substance having electron transport properties, can prevent the interaction between the electron injection buffer layer 119 and the P-type layer 117, and can smoothly transfer electrons. The LUMO energy level of the substance having electron transport properties contained in the electron relay layer 118 is preferably located between the LUMO energy level of the acceptor substance in the P-type layer 117 and the LUMO energy level of the substance contained in the layer in contact with the charge generation layer 116 in the electron transport layer 114. Specifically, when the LUMO energy level of the substance having electron transport properties in the electron relay layer 118 is -5.0 eV or higher, more preferably -5.0 eV or higher and -3.0 eV or lower, more preferably -4.30 eV or higher and -3.00 eV or lower, and more preferably -4.30 eV or higher and -3.30 eV or lower, the rise of the driving voltage can be suppressed, so it is preferred. In addition, as the substance having electron transport properties in the electron relay layer 118, a phthalocyanine material or a metal complex having a metal-oxygen bond and an aromatic ligand is preferably used.

[0238] As a substance with electron-transporting properties that can be used in the electronic relay layer 118, specifically, 2,3-diquinoxalino[2,3-a:2',3'-c]phenazine (abbreviation: HATNA), 2,3,8,9,14,15-hexafluorodiquinoxalino[2,3-a:2',3'-c]phenazine (abbreviation: HATNA-F6), 3,4,9,10-perylenetetracarboxylic diimide (abbreviation: PTCDI), 3,4,9,10-perylenetetracarboxylic acid-bis-benzimidazole (abbreviation: PTCBI) and other perylenetetracarboxylic acid derivatives, (C60-Ih)[5,6]fullerene (abbreviation: C60), (C70-D5h)[5,6]fullerene (abbreviation: C70) can be used. In addition, a compound having a heteroaromatic skeleton including a heterocycle can be used. As such a compound, for example, phthalocyanine (abbreviation: H 2 Pc) and other phthalocyanine compounds can be used. In addition, copper phthalocyanine (abbreviation: CuPc), zinc phthalocyanine (abbreviation: ZnPc), cobalt phthalocyanine (abbreviation: CoPc), iron phthalocyanine (abbreviation: FePc), tin phthalocyanine (abbreviation: SnPc), tin oxide phthalocyanine (abbreviation: SnOPc), titanium oxide phthalocyanine (abbreviation: TiOPc), vanadium oxide phthalocyanine (abbreviation: VOPc) and other metal phthalocyanines and their derivatives containing copper, zinc, cobalt, iron, chromium, nickel, etc. can also be used. In addition, phthalocyanine metal complexes such as copper phthalocyanine or zinc phthalocyanine or 2,3,8,9,14,15-hexafluorodiquinoxalino[2,3-a:2',3'-c]phenazine are particularly preferably used.

[0239] For the electron injection buffer layer 119, substances with high electron injection properties such as alkali metals, alkaline earth metals, rare earth metals, and compounds of these substances (alkali metal compounds (including oxides such as lithium oxide, halides, carbonates such as lithium carbonate or cesium carbonate), alkaline earth metal compounds (including oxides, halides, carbonates), or compounds of rare earth metals (including oxides, halides, carbonates)) can be used.

[0240] In addition, when the electron injection buffer layer 119 contains a substance with electron-transporting properties and a donor substance, as the donor substance, in addition to alkali metals, alkaline earth metals, rare earth metals, and compounds of these substances (alkali metal compounds (including oxides such as lithium oxide, halides, carbonates such as lithium carbonate or cesium carbonate), alkaline earth metal compounds (including oxides, halides, carbonates), or compounds of rare earth metals (including oxides, halides, carbonates)), organic compounds such as tetrathianaphthacene (abbreviation: TTN), nickelocene, and decamethylnickelocene can also be used. In addition, as the substance with electron-transporting properties, the same materials as those described above for the electron transport layer 114 can be used.

[0241] The second electrode 102 is an electrode including a cathode. The second electrode 102 may also have a stacked structure. In this case, the layer in contact with the organic compound layer 103 is used as the cathode. As the material for forming the cathode, metals, alloys, conductive compounds, and mixtures thereof with a small work function (specifically, 3.8 eV or less) can be used. Specific examples of such cathode materials include alkali metals such as lithium (Li) or cesium (Cs), elements belonging to Group 1 or Group 2 of the periodic table such as magnesium (Mg), calcium (Ca), or strontium (Sr), alloys containing them (MgAg, AlLi), compounds (lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF 2 ), etc.), rare earth metals such as europium (Eu) or ytterbium (Yb), and alloys containing them. However, by providing an electron injection layer 115 or a thin film of the above-mentioned material with a small work function between the second electrode 102 and the electron transport layer, various conductive materials such as Al, Ag, ITO, indium tin oxide containing silicon or silicon oxide, etc. can be used as the cathode regardless of the work function value.

[0242] When the second electrode 102 is made of a material that is transparent to visible light, a light-emitting device that emits light from the second electrode 102 side can be formed.

[0243] These conductive materials can be formed by dry methods such as vacuum evaporation, sputtering, inkjet printing, spin coating, etc. In addition, they can also be formed by wet methods such as sol-gel method or wet methods using pastes of metal materials.

[0244] In addition, as the method for forming the organic compound layer 103, various methods can be used regardless of whether it is a dry method or a wet method. For example, vacuum evaporation, gravure printing, offset printing, screen printing, inkjet printing, spin coating, etc. can also be used.

[0245] In addition, the above-described electrodes or layers can also be formed by using different film-forming methods.

[0246] Next, a description will be made with reference to Figure 1C the manner of a light-emitting device having a structure in which a plurality of light-emitting units are stacked (also referred to as a stacked element or a series element). This light-emitting device is a light-emitting device having a plurality of light-emitting units between an anode and a cathode. One light-emitting unit has a structure substantially the same as the Figure 1A organic compound layer 103 shown. That is to say, it can be said that the Figure 1C light-emitting device shown is a light-emitting device having a plurality of light-emitting units, while the Figure 1A or Figure 1B light-emitting device shown is a light-emitting device having one light-emitting unit.

[0247] In Figure 1CIn this case, a first light-emitting unit 511 and a second light-emitting unit 512 are stacked between a first electrode 501 and a second electrode 502, and a charge generation layer 513 is provided between the first light-emitting unit 511 and the second light-emitting unit 512. The first electrode 501 and the second electrode 502 respectively correspond to Figure 1A the first electrode 101 and the second electrode 102 in Figure 1A , and the same materials as those described in

[0248] can be applied. In addition, the first light-emitting unit 511 and the second light-emitting unit 512 may have the same structure or different structures. Figure 1C In

[0249] , when a voltage is applied to the first electrode 501 and the second electrode 502, the charge generation layer 513 has a function of injecting electrons into one light-emitting unit and injecting holes into the other light-emitting unit. In other words, in Figure 1B , when a voltage is applied such that the potential of the anode is higher than the potential of the cathode, it is only necessary for the charge generation layer 513 to inject electrons into the first light-emitting unit 511 and inject holes into the second light-emitting unit 512.

[0250] The charge generation layer 513 preferably has the same structure as the charge generation layer 116 shown in

[0251] . Since the composite material of the organic compound and the metal oxide has good carrier injection property and carrier transport property, low-voltage driving and low-current driving can be achieved. Note that when the surface on the anode side of the light-emitting unit is in contact with the charge generation layer 513, the charge generation layer 513 can have the function of the hole injection layer of the light-emitting unit, so the light-emitting unit may not be provided with a hole injection layer. Figure 1C In addition, when an electron injection buffer layer 119 is provided in the charge generation layer 513, since the electron injection buffer layer 119 has the function of the electron injection layer in the light-emitting unit on the anode side, it is not necessarily required to provide an electron injection layer in the light-emitting unit on the anode side.

[0252] Although a light-emitting device having two light-emitting units is described in Figure 1C , a light-emitting device in which three or more light-emitting units are stacked can be similarly applied. In the light-emitting device according to the present embodiment, by separating and arranging a plurality of light-emitting units between a pair of electrodes using the charge generation layer 513, the element can achieve high-brightness light emission while maintaining a low current density, and a long-life element can be realized. In addition, a light-emitting device capable of low-voltage driving and low power consumption can be realized.

[0252] In addition, by making the emission colors of the respective light-emitting units different, light emission of a desired color can be obtained from the entire light-emitting device. For example, in a light-emitting device having two light-emitting units, by obtaining red and green emission colors from the first light-emitting unit and a blue emission color from the second light-emitting unit, a light-emitting device that emits white light throughout the entire light-emitting device can be obtained.

[0253] In addition, each layer such as the above-described organic compound layer 103, the first light-emitting unit 511, the second light-emitting unit 512, and the charge generation layer, and the electrodes can be formed, for example, by a vapor deposition method (including a vacuum vapor deposition method), a droplet ejection method (also referred to as an inkjet method), a coating method, a gravure printing method, or the like. Further, they may include a low molecular weight material, a medium molecular weight material (including an oligomer, a dendrimer), or a high molecular weight material.

[0254] Embodiment 3

[0255] In this embodiment, reference is made to Figure 3A and Figure 3B to describe a display device manufactured using the light-emitting device shown in Embodiment 1 and Embodiment 2. Note that Figure 3A is a top view of the display device, and Figure 3B is a cross-sectional view taken along lines A-B and C-D in Figure 3A . The display device includes a drive circuit unit (source line drive circuit) 601, a pixel unit 602, and a drive circuit unit (gate line drive circuit) 603, which are represented by dotted lines, as units for controlling the light emission of the light-emitting device. In addition, reference numeral 604 denotes a sealing substrate, reference numeral 605 denotes a sealing material, and the inside surrounded by the sealing material 605 is a space 607.

[0256] Note that the guiding wiring 608 is a wiring for transmitting signals input to the source line drive circuit 601 and the gate line drive circuit 603, and receives a video signal, a clock signal, a start signal, a reset signal, etc. from an FPC (flexible printed circuit) 609 serving as an external input terminal. Note that although only the FPC is illustrated here, a printed wiring board (PWB) may also be mounted on the FPC. The display device in this specification includes not only the display device main body but also a display device on which an FPC or a PWB is mounted.

[0257] Next, the cross-sectional structure will be described with reference to Figure 3B . Although the drive circuit unit and the pixel unit are formed on the element substrate 610, one pixel in the source line drive circuit 601 and the pixel unit 602, which are the drive circuit units, is shown here.

[0258] The element substrate 610 may use a plastic substrate made of FRP (Fiber Reinforced Plastics), PVF (polyvinyl fluoride), polyester, acrylic resin, etc., in addition to a substrate made of glass, quartz, organic resin, metal, alloy, semiconductor, etc.

[0259] There is no particular limitation on the structure of the transistors used for the pixels and the driving circuit. For example, an anti-staggered transistor or a staggered transistor may be employed. Additionally, a top-gate transistor or a bottom-gate transistor may also be used. There is no particular limitation on the semiconductor material used for the transistors. For example, silicon, germanium, silicon carbide, gallium nitride, etc. may be used. Or an oxide semiconductor containing at least one of indium, gallium, and zinc, such as an In-Ga-Zn-based metal oxide, may be used.

[0260] There is also no particular limitation on the crystallinity of the semiconductor material used for the transistors. An amorphous semiconductor or a semiconductor having crystallinity (microcrystalline semiconductor, polycrystalline semiconductor, single-crystalline semiconductor, or a semiconductor having a crystalline region in a part thereof) may be used. When a semiconductor having crystallinity is used, deterioration of the transistor characteristics can be suppressed, which is thus preferred.

[0261] Here, an oxide semiconductor is preferably used for semiconductor devices such as transistors provided in the above-mentioned pixels and driving circuits and transistors for a touch sensor described later. An oxide semiconductor having a bandgap wider than that of silicon is particularly preferably used. By using an oxide semiconductor having a bandgap wider than that of silicon, the off-state current of the transistor can be reduced.

[0262] The above-mentioned oxide semiconductor preferably contains at least indium (In) or zinc (Zn). Additionally, the above-mentioned oxide semiconductor is more preferably an oxide semiconductor containing an oxide represented by In-M-Zn-based oxides (M is a metal such as Al, Ti, Ga, Ge, Y, Zr, Sn, La, Ce, or Hf).

[0263] In particular, as the semiconductor layer, an oxide semiconductor film is preferably used which has a plurality of crystal parts, in which the c-axis is oriented in a direction perpendicular to the formation surface or the top surface of the semiconductor layer, and there are no grain boundaries between adjacent crystal parts.

[0264] By using the above materials as the semiconductor layer, fluctuations in electrical characteristics can be suppressed, and a highly reliable transistor can be realized.

[0265] In addition, since the off-state current of the transistor having the above-described semiconductor layer is low, the charge stored in the capacitor through the transistor can be maintained for a long period of time. By using such a transistor for a pixel, the drive circuit can be stopped while maintaining the gradation of the pixels displayed in each display region. As a result, an electronic device with extremely low power consumption can be realized.

[0266] In order to stabilize the characteristics of the transistor, etc., it is preferable to provide a base film. As the base film, an inorganic insulating film such as a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or a silicon nitride oxide film can be used and formed as a single layer or a laminate. The base film can be formed by a sputtering method, a CVD (Chemical Vapor Deposition) method (a plasma CVD method, a thermal CVD method, an MOCVD (Metal Organic CVD) method, etc.), an ALD (Atomic Layer Deposition) method, a coating method, a printing method, etc. Note that the base film may not be provided if not necessary.

[0267] Note that the FET 623 shows one of the transistors formed in the drive circuit unit 601. In addition, the drive circuit can also be formed using various CMOS circuits, PMOS circuits, or NMOS circuits. In addition, although the driver integrated type in which the drive circuit is formed on the substrate is shown in the present embodiment, it is not necessarily required to adopt this structure, and the drive circuit can also be formed outside and not on the substrate.

[0268] In addition, the pixel unit 602 is formed of a plurality of pixels, and each of the plurality of pixels includes a switching FET 611, a current control FET 612, and a first electrode 613 electrically connected to the drain of the current control FET 612. However, it is not limited thereto, and a pixel unit combining three or more FETs and capacitors can also be adopted.

[0269] Note that an insulator 614 is formed so as to cover the end portion of the first electrode 613. Here, a positive photosensitive acrylic resin film can be used to form the insulator 614.

[0270] In addition, the upper end portion or the lower end portion of the insulator 614 is formed into a curved surface having a curvature to obtain good coverage of an organic compound layer or the like formed later. For example, when a positive photosensitive acrylic resin is used as the material of the insulator 614, it is preferable that only the upper end portion of the insulator 614 includes a curved surface having a radius of curvature (0.2 μm to 3 μm). As the insulator 614, a negative photosensitive resin or a positive photosensitive resin can be used.

[0271] An organic compound layer 616 and a second electrode 617 are formed on the first electrode 613. Here, as the material for the first electrode 613 used as an anode, a material with a large work function is preferably used. For example, in addition to single-layer films such as ITO films, indium tin oxide films containing silicon, indium oxide films containing 2 wt% to 20 wt% of zinc oxide, titanium nitride films, chromium films, tungsten films, Zn films, Pt films, etc., a laminated film composed of a titanium nitride film and a film mainly composed of aluminum and a three-layer structure composed of a titanium nitride film, a film mainly composed of aluminum, and a titanium nitride film can also be used. Note that when a laminated structure is adopted, the resistance value of the wiring can be low, good ohmic contact can be obtained, and it can be used as an anode.

[0272] In addition, the organic compound layer 616 is formed by various methods such as vapor deposition using a vapor deposition mask, inkjet method, spin coating method, etc. The organic compound layer 616 includes the structures shown in Embodiment 1 and Embodiment 2. In addition, as other materials constituting the organic compound layer 616, low molecular compounds or high molecular compounds (including oligomers, dendrimers) can also be used.

[0273] In addition, as the material for the second electrode 617 formed on the organic compound layer 616 and used as a cathode, a material with a small work function (Al, Mg, Li, Ca, or their alloys and compounds (MgAg, MgIn, AlLi, etc.)) is preferably used. Note that when allowing the light generated in the organic compound layer 616 to pass through the second electrode 617, a laminate composed of a thin metal film and a transparent conductive film (ITO, indium oxide containing 2 wt% to 20 wt% of zinc oxide, indium tin oxide containing silicon, zinc oxide (ZnO), etc.) is preferably used as the second electrode 617.

[0274] In addition, the light-emitting device is formed by the first electrode 613, the organic compound layer 616, and the second electrode 617. This light-emitting device is the light-emitting device shown in Embodiment 1 and Embodiment 2. In addition, the pixel portion is composed of a plurality of light-emitting devices, and the display device of the present embodiment may also include both the light-emitting devices shown in Embodiment 1 and Embodiment 2 and light-emitting devices with other structures.

[0275] In addition, the sealing substrate 604 is attached to the element substrate 610 using a sealing material 605, and the light-emitting device 618 is disposed in a space 607 surrounded by the element substrate 610, the sealing substrate 604, and the sealing material 605. Note that the space 607 is filled with a filler. As this filler, an inert gas (nitrogen, argon, etc.) can be used, and a sealing material can also be used. By forming a recess in the sealing substrate and disposing a desiccant therein, deterioration caused by the influence of moisture can be suppressed, so it is preferable.

[0276] In addition, it is preferable to use epoxy resin and glass powder as the sealing material 605. Additionally, these materials are preferably those that do not allow moisture and oxygen to permeate as much as possible. In addition, as the material for sealing the substrate 604, in addition to glass substrates and quartz substrates, plastic substrates made of FRP (Fiber Reinforced Plastics), PVF (polyvinyl fluoride), polyester, acrylic resin, etc. can also be used.

[0277] Although not shown in Figure 3A and Figure 3B a protective film can also be provided on the second electrode. The protective film can be formed of an organic resin film or an inorganic insulating film. Additionally, the protective film can be formed in such a way as to cover the exposed portion of the sealing material 605. Further, the protective film can be provided to cover the exposed sides of the surfaces and sides of the pair of substrates, the sealing layer, the insulating layer, etc.

[0278] As the protective film, a material that does not easily allow impurities such as water to permeate can be used. Therefore, the diffusion of impurities such as water from the outside to the inside can be efficiently suppressed.

[0279] As the material constituting the protective film, oxides, nitrides, fluorides, sulfides, ternary compounds, metals, or polymers, etc. can be used. For example, materials containing aluminum oxide, hafnium oxide, hafnium silicate, lanthanum oxide, silicon oxide, strontium titanate, tantalum oxide, titanium oxide, zinc oxide, niobium oxide, zirconium oxide, tin oxide, yttrium oxide, cerium oxide, scandium oxide, erbium oxide, vanadium oxide, or indium oxide, etc., materials containing aluminum nitride, hafnium nitride, silicon nitride, tantalum nitride, titanium nitride, niobium nitride, molybdenum nitride, zirconium nitride, gallium nitride, etc., materials containing nitrides containing titanium and aluminum, oxides containing titanium and aluminum, oxides containing aluminum and zinc, sulfides containing manganese and zinc, sulfides containing cerium and strontium, oxides containing erbium and aluminum, oxides containing yttrium and zirconium, etc. can be used.

[0280] The protective film is preferably formed by a deposition method with good step coverage. One of such methods is the atomic layer deposition (ALD) method. It is preferable to use a material that can be formed by the ALD method for the protective film. By the ALD method, a protective film that is dense and has reduced defects such as cracks and pinholes or has a uniform thickness can be formed. Additionally, the damage to the processing components during the formation of the protective film can be reduced.

[0281] For example, by forming the protective film by the ALD method, a protective film that is uniform and has few defects can be formed on the surface with a complex uneven shape or on the top surface, side surface, and back surface of the touch panel.

[0282] As described above, a display device manufactured using the light-emitting devices shown in Embodiment 1 and Embodiment 2 can be obtained.

[0283] Since the light-emitting device in the present embodiment uses the light-emitting devices shown in Embodiment 1 and Embodiment 2, a light-emitting device having excellent characteristics can be obtained. Specifically, the light-emitting devices shown in Embodiment 1 and Embodiment 2 have high luminous efficiency, and thus a display device with low power consumption can be realized. In addition, the light-emitting devices shown in Embodiment 1 and Embodiment 2 have high reliability, and thus a display device with high reliability can be realized. Also, the light-emitting devices shown in Embodiment 1 and Embodiment 2 can have good chromaticity and high color purity, and thus a display device with good display quality can be realized.

[0284] In addition, the present embodiment can be freely combined with other embodiments.

[0285] Embodiment 4

[0286] As Figure 4A and Figure 4B shown, a plurality of light-emitting devices 130 are formed on the insulating layer 175 and constitute a display device. In the present embodiment, a display device according to another aspect of the present invention will be described in detail.

[0287] The display device 100 includes a pixel portion 177 in which a plurality of pixels 178 are arranged in a matrix. The pixel 178 includes a sub-pixel 110R, a sub-pixel 110G, and a sub-pixel 110B.

[0288] In this specification and the like, for example, when describing the common content among the sub-pixels 110R, the sub-pixels 110G, and the sub-pixels 110B, it is sometimes described as the sub-pixel 110. Similarly, when describing the common content among other components distinguished by letters, it is sometimes described using symbols omitting the letters.

[0289] The sub-pixel 110R emits red light, the sub-pixel 110G emits green light, and the sub-pixel 110B emits blue light. Thus, an image can be displayed on the pixel portion 177. In the present embodiment, sub-pixels of three colors, red (R), green (G), and blue (B), are taken as an example, but a combination of sub-pixels of other colors can also be used. In addition, the number of sub-pixels is not limited to three, and four or more can also be used. As four sub-pixels, for example, sub-pixels of four colors, R, G, B, and white (W); sub-pixels of four colors, R, G, B, and yellow (Y); and sub-pixels of four colors, R, G, B, and infrared light (IR); etc. can be cited.

[0290] In this specification and the like, the row direction is sometimes denoted as the X direction and the column direction is denoted as the Y direction. The X direction and the Y direction intersect, for example, perpendicularly.

[0291] In Figure 4A In the example shown, sub-pixels of different colors are arranged and configured in the X direction, and sub-pixels of the same color are arranged and configured in the Y direction. Note that sub-pixels of different colors may also be arranged and configured in the Y direction, and sub-pixels of the same color may also be arranged and configured in the X direction.

[0292] A connection portion 140 is provided outside the pixel portion 177, and an area 141 may also be provided. In the case where the area 141 is provided, the area 141 is provided between the pixel portion 177 and the connection portion 140. In the case where the area 141 is provided, an organic compound layer is provided in the area 141. In addition, a conductive layer 151C is provided in the connection portion 140.

[0293] In Figure 4A In the example shown, the area 141 and the connection portion 140 are located on the right side of the pixel portion 177, but there is no particular limitation on the positions of the area 141 and the connection portion 140. In addition, the area 141 and the connection portion 140 may be one or more.

[0294] Figure 4B is an example of a cross-sectional view along the Figure 4A dotted line A1 - A2 in. As Figure 4B shown, the display device 100 includes an insulating layer 171, a conductive layer 172 on the insulating layer 171, an insulating layer 173 on the insulating layer 171 and on the conductive layer 172, an insulating layer 174 on the insulating layer 173, and an insulating layer 175 on the insulating layer 174. The insulating layer 171 is provided on a substrate (not shown). The insulating layer 175, the insulating layer 174, and the insulating layer 173 are provided with openings reaching the conductive layer 172, and plugs 176 are provided in such a manner as to be embedded in the openings.

[0295] In the pixel portion 177, a light-emitting device 130 is provided on the insulating layer 175 and the plugs 176. In addition, a protective layer 131 is provided so as to cover the light-emitting device 130. The substrate 120 is bonded to the protective layer 131 by a resin layer 122. In addition, an inorganic insulating layer 125 and an insulating layer 127 on the inorganic insulating layer 125 are preferably provided between adjacent light-emitting devices 130.

[0296] Figure 4B Cross-sections of a plurality of inorganic insulating layers 125 and a plurality of insulating layers 127 are shown, but when viewing the display device 100 from above, the inorganic insulating layer 125 and the insulating layer 127 are preferably formed as a connected single layer, respectively.

[0297] In Figure 4BAs the light-emitting device 130, the light-emitting device 130R, the light-emitting device 130G, and the light-emitting device 130B are shown. The light-emitting device 130R, the light-emitting device 130G, and the light-emitting device 130B can emit light of different colors from each other. For example, the light-emitting device 130R can emit red light, the light-emitting device 130G can emit green light, and the light-emitting device 130B can emit blue light. In addition, the light-emitting device 130R, the light-emitting device 130G, or the light-emitting device 130B can also emit other visible light or infrared light.

[0298] A display device according to one embodiment of the present invention can have, for example, a top emission structure that emits light in a direction opposite to the substrate on which the light-emitting device is formed. In addition, a display device according to one embodiment of the present invention can also have a bottom emission structure.

[0299] The light-emitting device 130R includes a first electrode 101R (pixel electrode) composed of a conductive layer 151R and a conductive layer 152R, an organic compound layer 103R on the first electrode, a common layer 104 on the organic compound layer 103R, and a second electrode (common electrode) 102 on the common layer 104. Note that the common layer 104 may not be provided, but when the common layer 104 is provided, damage to the organic compound layer 103R during processing can be reduced, so it is preferable.

[0300] The light-emitting device 130G includes a first electrode 101G (pixel electrode) composed of a conductive layer 151G and a conductive layer 152G, an organic compound layer 103G on the first electrode, a common layer 104 on the organic compound layer 103G, and a second electrode (common electrode) 102 on the common layer 104. In addition, the common layer 104 may not be provided, but when it is provided, damage to the organic compound layer 103G during processing can be reduced, so it is preferable.

[0301] The light-emitting device 130B has the structure shown in Embodiment 1 and Embodiment 2. The light-emitting device 130B includes a first electrode 101B (pixel electrode) composed of a conductive layer 151B and a conductive layer 152B, an organic compound layer 103B on the first electrode, a common layer 104 on the organic compound layer 103B, and a second electrode (common electrode) 102 on the common layer 104. In addition, the common layer 104 may not be provided, but when it is provided, damage to the organic compound layer 103B during processing can be reduced, so it is preferable. In addition, when the common layer 104 is provided, the stacked structure of the organic compound layer 103B and the common layer 104 corresponds to the organic compound layer 103 in Embodiment 1 and Embodiment 2.

[0302] In addition, the common layer 104 is preferably an electron injection layer or an electron transport layer, more preferably an electron injection layer. Further, in the case where the common layer 104 is an electron transport layer, the electron transport layer preferably has a stacked structure. More preferably, the layer on the second electrode side among the stacked layers is the common layer 104, and the layer on the light-emitting layer side is the organic compound layer 103.

[0303] In addition, the light-emitting devices 130R and 130G are also light-emitting devices manufactured through a photolithography process, whereby a light-emitting device with a low driving voltage in which an increase in the driving voltage due to the photolithography process is suppressed can be realized.

[0304] One of the pixel electrode and the common electrode included in the light-emitting device 130 is used as the anode, and the other is used as the cathode. Hereinafter, unless otherwise specified, the case where the pixel electrode is used as the anode and the common electrode is used as the cathode will be described.

[0305] The organic compound layers 103R, 103G, and 103B are independent in island shapes for each light-emitting device or for each light-emitting color. By providing the organic compound layer 103 in an island shape for each light-emitting device 130, leakage current between adjacent light-emitting devices 130 can be suppressed even in a high-definition display device. Thereby, crosstalk can be prevented to realize a display device with extremely high contrast. In particular, a display device with high current efficiency at low luminance can be realized.

[0306] The island-shaped organic compound layer 103 is formed by depositing an organic compound film and processing the organic compound film using photolithography.

[0307] The organic compound layer 103 is preferably provided so as to cover the top surface and the side surface of the first electrode (pixel electrode) of the light-emitting device 130. Thereby, compared with a structure in which the end portion of the organic compound layer 103 is located inside the end portion of the pixel electrode, it is easy to increase the aperture ratio of the display device 100. In addition, by covering the side surface of the pixel electrode of the light-emitting device 130 with the organic compound layer 103, contact between the pixel electrode and the second electrode 102 can be suppressed, and thus short circuit of the light-emitting device 130 can be suppressed.

[0308] In the display device according to one embodiment of the present invention, the first electrode (pixel electrode) of the light-emitting device preferably has a stacked structure. For example, in Figure 4B the example shown, the first electrode of the light-emitting device 130 has a stacked structure of a conductive layer 151 and a conductive layer 152.

[0309] As the conductive layer 151, a metal material can be used, for example. Specifically, metals such as aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), neodymium (Nd), etc. and alloys obtained by appropriately combining them can be used.

[0310] As the conductive layer 152, an oxide containing one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon can be used. For example, a conductive oxide including one or more of indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, zinc oxide containing gallium, titanium oxide, indium zinc oxide containing gallium, indium zinc oxide containing aluminum, indium tin oxide containing silicon, and indium zinc oxide containing silicon is preferably used. In particular, indium tin oxide containing silicon has a relatively large work function, for example, 4.0 eV or more, and thus can be suitably used as the conductive layer 152.

[0311] The conductive layer 151 and the conductive layer 152 may each have a laminated structure including a plurality of layers containing different materials. In this case, the conductive layer 151 may include a layer using a material such as a conductive oxide that can be used for the conductive layer 152, and the conductive layer 152 may include a layer using a material such as a metal material that can be used for the conductive layer 151. For example, when the conductive layer 151 has a laminated structure of two or more layers, the layer in contact with the conductive layer 152 may be a layer using a material that can be used for the conductive layer 152.

[0312] In addition, the side surface of the conductive layer 151 preferably has a tapered shape. Specifically, the side surface of the conductive layer 151 preferably has a tapered shape with a taper angle less than 90°. At this time, the conductive layer 152 provided along the side surface of the conductive layer 151 also has a tapered shape. By making the side surface of the conductive layer 152 have a tapered shape, the coverage of the organic compound layer 103 provided along the side surface of the conductive layer 152 can be improved.

[0313] Next, with reference to Figures 5A to 10C An example of a manufacturing method of the display device 100 having the Figure 4A shown structure will be described.

[0314] [Example of Manufacturing Method 1]

[0315] The thin films (insulating films, semiconductor films, conductive films, etc.) constituting the display device can be formed by a sputtering method, a chemical vapor deposition (CVD: Chemical Vapor Deposition) method, a vacuum evaporation method, a pulsed laser deposition (PLD: Pulsed Laser Deposition) method, an ALD method, or the like.

[0316] In addition, thin films (such as insulating films, semiconductor films, and conductive films) constituting the display device can be formed by wet deposition methods such as spin coating, dipping, spraying, inkjet printing, dispenser method, screen printing, offset printing, doctor knife method, slot die coating, roll coating, curtain coating, or blade coating.

[0317] In addition, when processing the thin films constituting the display device, for example, photolithography can be used for processing.

[0318] In photolithography, as the light for exposure, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or light obtained by mixing these lights can be used. In addition, ultraviolet light, KrF laser, or ArF laser can also be used. In addition, immersion exposure technology can also be used for exposure. In addition, as the light for exposure, extreme ultraviolet (EUV) light or X-rays can also be used. In addition, instead of the light for exposure, an electron beam can also be used.

[0319] In the etching of thin films, dry etching, wet etching, sandblasting, or the like can be used.

[0320] First, as Figure 5A shown, an insulating layer 171 is formed on a substrate (not shown). Next, a conductive layer 172 and a conductive layer 179 are formed on the insulating layer 171, and an insulating layer 173 is formed on the insulating layer 171 so as to cover the conductive layer 172 and the conductive layer 179. Next, an insulating layer 174 is formed on the insulating layer 173, and an insulating layer 175 is formed on the insulating layer 174.

[0321] As the substrate, a substrate having at least heat resistance capable of withstanding subsequent heat treatment can be used. For example, a glass substrate; a quartz substrate; a sapphire substrate; a ceramic substrate; an organic resin substrate; or a semiconductor substrate such as a single crystal semiconductor substrate and a polycrystalline semiconductor substrate made of silicon or silicon carbide, a compound semiconductor substrate such as silicon germanium, or an SOI substrate can be used.

[0322] Next, as Figure 5A shown, openings reaching the conductive layer 172 are formed in the insulating layer 175, the insulating layer 174, and the insulating layer 173. Next, a plug 176 is formed so as to embed the openings.

[0323] Next, as Figure 5AAs shown, after being formed on the plug 176 and the insulating layer 175, there are formed a conductive film 151f that later becomes the conductive layers 151R, 151G, 151B, and 151C, and a conductive film 152f that later becomes the conductive layers 152R, 152G, 152B, and 152C. As the conductive film 151f, for example, a metal material can be used. As the conductive film 152f, for example, an oxide containing one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon can be used.

[0324] Next, as Figure 5A shown, a resist mask 191 is formed on the conductive film 152f. The resist mask 191 can be formed by applying a photosensitive material (photoresist) and then performing exposure and development.

[0325] Next, as Figure 5B shown, for example, the conductive film 151f and the conductive film 152f in the regions not overlapping with the resist mask 191 are removed. Thereby, the conductive layers 151 and 152 are formed.

[0326] Next, as Figure 5C shown, the resist mask 191 is removed. The resist mask 191 can be removed, for example, by ashing using oxygen plasma.

[0327] Next, as Figure 5D shown, an insulating film 156f that will later become the insulating layers 156R, 156G, 156B, and 156C is formed on the conductive layers 152R, 152G, 152B, 152C, and the insulating layer 175.

[0328] The insulating film 156f can use an inorganic insulating film such as an oxide insulating film, a nitride insulating film, an oxynitride insulating film, or a nitrogen oxide insulating film. For example, silicon oxynitride can be used.

[0329] Next, as Figure 5E shown, by processing the insulating film 156f, the insulating layers 156R, 156G, 156B, and 156C are formed.

[0330] Next, as Figure 6A shown, an organic compound film 103Rf is formed on the conductive layers 152R, 152G, 152B, and the insulating layer 175. In addition, as Figure 6A shown, the organic compound film 103Rf is not formed on the conductive layer 152C.

[0331] Next, as Figure 6A shown, a sacrificial film 158Rf and a mask film 159Rf are formed.

[0332] By providing a sacrificial film 158Rf on the organic compound film 103Rf, damage to the organic compound film 103Rf during the manufacturing process of the display device can be reduced, and the reliability of the light-emitting device can be improved.

[0333] As the sacrificial film 158Rf, a film with high resistance to the processing conditions of the organic compound film 103Rf is used. Specifically, a film with a large etching selectivity ratio with respect to the organic compound film 103Rf. As the mask film 159Rf, a film with a large etching selectivity ratio with respect to the sacrificial film 158Rf is used.

[0334] In addition, the sacrificial film 158Rf and the mask film 159Rf are formed at a temperature lower than the heat-resistant temperature of the organic compound film 103Rf. The substrate temperature during the formation of the sacrificial film 158Rf and the mask film 159Rf is typically 100°C or higher and 200°C or lower, preferably 100°C or higher and 150°C or lower, and more preferably 100°C or higher and 120°C or lower. Since the light-emitting device according to one embodiment of the present invention contains a first organic compound, a display device with high display quality can be provided even after a heating process at a higher temperature.

[0335] As the sacrificial film 158Rf and the mask film 159Rf, a film that can be removed by a wet etching method or a dry etching method is preferably used.

[0336] In addition, the sacrificial film 158Rf formed in contact with the organic compound film 103Rf is preferably formed by a formation method that causes less damage to the organic compound film 103Rf than the mask film 159Rf. For example, compared with the sputtering method, the ALD method (atomic layer deposition method) or the vacuum evaporation method is more preferably used.

[0337] As the sacrificial film 158Rf and the mask film 159Rf, for example, one or more of a metal film, an alloy film, a metal oxide film, a semiconductor film, an organic insulating film, and an inorganic insulating film can be used.

[0338] As the sacrificial film 158Rf and the mask film 159Rf, for example, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, and tantalum, or alloy materials containing these metal materials can be used respectively. In particular, low melting point materials such as aluminum or silver are preferably used. By using a metal material capable of shielding ultraviolet rays as one or both of the sacrificial film 158Rf and the mask film 159Rf, ultraviolet rays can be prevented from irradiating the organic compound film 103Rf during pattern exposure, and deterioration of the organic compound film 103Rf can be suppressed, so it is preferable.

[0339] In addition, as the sacrificial film 158Rf and the mask film 159Rf, metal oxides such as In-Ga-Zn oxide, indium oxide, In-Zn oxide, In-Sn oxide, indium-titanium oxide (In-Ti oxide), indium-tin-zinc oxide (In-Sn-Zn oxide), indium-titanium-zinc oxide (In-Ti-Zn oxide), indium-gallium-tin-zinc oxide (In-Ga-Sn-Zn oxide), indium-tin oxide containing silicon, etc. can be used respectively.

[0340] Note that an element M (M is one or more of aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium) can also be used in the above metal oxides to replace the above gallium.

[0341] As the sacrificial film 158Rf and the mask film 159Rf, semiconductor materials such as silicon or germanium are used, for example. This has a high affinity with the semiconductor manufacturing process, so it is preferred. In addition, compounds containing the above semiconductor materials can be used.

[0342] As the sacrificial film 158Rf and the mask film 159Rf, various inorganic insulating films can be used respectively. In particular, the adhesion of the oxide insulating film to the organic compound film 103Rf is higher than that of the nitride insulating film to the organic compound film 103Rf, so it is preferred.

[0343] Next, as Figure 6A shown, a resist mask 190R is formed. The resist mask 190R can be formed by coating a photosensitive material (photoresist) and then performing exposure and development.

[0344] The resist mask 190R is provided at a position overlapping with the conductive layer 152R. The resist mask 190R is preferably also provided at a position overlapping with the conductive layer 152C. Thereby, damage to the conductive layer 152C during the manufacturing process of the display device can be suppressed.

[0345] Next, as Figure 6B shown, a part of the mask film 159Rf is removed using the resist mask 190R to form a mask layer 159R. The mask layer 159R remains on the conductive layer 152R and the conductive layer 152C. Then, the resist mask 190R is removed. Next, the mask layer 159R is used as a mask (also called a hard mask) to remove a part of the sacrificial film 158Rf to form a sacrificial layer 158R.

[0346] By using a wet etching method, compared with the case of using a dry etching method, damage to the organic compound film 103Rf during the processing of the sacrificial film 158Rf and the mask film 159Rf can be reduced. When using a wet etching method, for example, an alkaline aqueous solution such as a developer, an aqueous solution of tetramethylammonium hydroxide (TMAH), dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or an acidic aqueous solution such as a liquid medicine using a mixture thereof is preferably used.

[0347] In addition, when using a dry etching method during the processing of the sacrificial film 158Rf, deterioration of the organic compound film 103Rf can be suppressed by not using an oxygen-containing gas as an etching gas.

[0348] The resist mask 190R and the resist mask 191 can be removed by the same method.

[0349] Next, as Figure 6B shown, the organic compound film 103Rf is processed to form the organic compound layer 103R. For example, the mask layer 159R and the sacrificial layer 158R are used as a hard mask and a part of the organic compound film 103Rf is removed, thereby forming the organic compound layer 103R.

[0350] Thus, as Figure 6B shown, a stacked structure of the organic compound layer 103R, the sacrificial layer 158R, and the mask layer 159R remains on the conductive layer 152R. In addition, the conductive layer 152G and the conductive layer 152B are exposed.

[0351] The processing of the organic compound film 103Rf is preferably performed using anisotropic etching. Anisotropic dry etching is particularly preferably used. Alternatively, wet etching may also be used.

[0352] When using a dry etching method, deterioration of the organic compound film 103Rf can be suppressed by not using an oxygen-containing gas as an etching gas.

[0353] In addition, an oxygen-containing gas can also be used as an etching gas. When the etching gas contains oxygen, the etching rate can be increased. Therefore, etching can be performed under low power conditions while maintaining a sufficient etching rate. Therefore, damage to the organic compound film 103Rf can be suppressed. And, defects such as adhesion of reaction products generated during etching can be suppressed.

[0354] When using a dry etching method, for example, it is preferable to use a gas containing H 2 , CF 4 , C 4 F 8 , SF 6 , CHF 3 , Cl 2 , H 2 O, BCl 3One or more gases of Group 18 elements such as He and Ar are used as the etching gas. Alternatively, preferably, a gas containing one or more of the above gases and oxygen is used as the etching gas. Alternatively, oxygen gas may also be used as the etching gas.

[0355] Next, as Figure 7A shown, an organic compound film 103Gf that will later become the organic compound layer 103G is formed.

[0356] The organic compound film 103Gf can be formed by the same method as that used for forming the organic compound film 103Rf. In addition, the organic compound film 103Gf can have the same structure as the organic compound film 103Rf.

[0357] Next, as Figure 7A shown, a sacrificial film 158Gf and a mask film 159Gf are sequentially formed. Then, a resist mask 190G is formed. The materials and formation methods of the sacrificial film 158Gf and the mask film 159Gf are the same as the conditions applicable to the sacrificial film 158Rf and the mask film 159Rf. The materials and formation methods of the resist mask 190G are the same as the conditions applicable to the resist mask 190R.

[0358] The resist mask 190G is disposed at a position overlapping with the conductive layer 152G.

[0359] Next, as Figure 7B shown, a part of the mask film 159Gf is removed using the resist mask 190G, thereby forming a mask layer 159G. The mask layer 159G remains on the conductive layer 152G. Then, the resist mask 190G is removed. Next, using the mask layer 159G as a mask, a part of the sacrificial film 158Gf is removed, thereby forming a sacrificial layer 158G. Next, the organic compound film 103Gf is processed to form the organic compound layer 103G.

[0360] Next, as Figure 7C shown, an organic compound film 103Bf is formed.

[0361] The organic compound film 103Bf can be formed by the same method as that used for forming the organic compound film 103Rf. In addition, the organic compound film 103Bf can have the same structure as the organic compound film 103Rf.

[0362] Next, as Figure 7CAs shown, a sacrificial film 158Bf and a mask film 159Bf are formed in sequence. Then, a resist mask 190B is formed. The materials and formation methods of the sacrificial film 158Bf and the mask film 159Bf are the same as the conditions applicable to the sacrificial film 158Rf and the mask film 159Rf. The materials and formation methods of the resist mask 190B are the same as the conditions applicable to the resist mask 190R.

[0363] The resist mask 190B is formed at a position overlapping with the conductive layer 152B.

[0364] Next, as Figure 7D shown, a part of the mask film 159Bf is removed using the resist mask 190B, thereby forming a mask layer 159B. The mask layer 159B remains on the conductive layer 152B. Then, the resist mask 190B is removed. Next, the mask layer 159B is used as a mask to remove a part of the sacrificial film 158Bf, thereby forming a sacrificial layer 158B. Then, the organic compound film 103Bf is processed to form an organic compound layer 103B. For example, a part of the organic compound film 103Bf is removed using the mask layer 159B and the sacrificial layer 158B as hard masks to form the organic compound layer 103B.

[0365] Thus, as Figure 7D shown, a stacked structure of the organic compound layer 103B, the sacrificial layer 158B, and the mask layer 159B remains on the conductive layer 152B. In addition, the mask layer 159R and the mask layer 159G are exposed.

[0366] Note that the sides of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B are each preferably perpendicular or substantially perpendicular to the formation surface. For example, the angle formed by the formation surface and these sides is preferably 60 degrees or more and 90 degrees or less.

[0367] As described above, the distance between two adjacent ones of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B formed by photolithography can be reduced to 8 μm or less, 5 μm or less, 3 μm or less, 2 μm or less, or 1 μm or less. Here, for example, this distance can be defined based on the distance between the opposite end portions of two adjacent organic compound layers among the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B. Thus, by reducing the distance between the island-shaped organic compound layers, a display device with high clarity and a large aperture ratio can be provided. In addition, the distance between the first electrodes of adjacent light-emitting devices can be reduced, for example, to 10 μm or less, 8 μm or less, 5 μm or less, 3 μm or less, 2 μm or less. In addition, the distance between the first electrodes of adjacent light-emitting devices is preferably 2 μm or more and 5 μm or less.

[0368] Next, as Figure 8A shown, it is preferable to remove the mask layer 159R, the mask layer 159G, and the mask layer 159B.

[0369] As the process for removing the mask layer, the same method as the process for processing the mask film can be used. In particular, by using the wet etching method, the damage to the organic compound layer 103 during the removal of the mask layer can be reduced compared to the case of using the dry etching method.

[0370] Alternatively, the mask layer can be removed by dissolving it in a polar solvent such as water or alcohol. As the alcohol, ethanol, methanol, isopropyl alcohol (IPA), or glycerol, etc. can be cited.

[0371] After removing the mask layer, a drying process can also be performed to remove the water on the surface. For example, heat treatment can also be performed in an inert gas atmosphere or a reduced pressure atmosphere. The heat treatment can be performed at a substrate temperature of 50°C or higher and 200°C or lower, preferably 60°C or higher and 150°C or lower, and more preferably 70°C or higher and 120°C or lower. By adopting a reduced pressure atmosphere, drying can be performed at a lower temperature, so it is preferable.

[0372] Next, as Figure 8B shown, an inorganic insulating film 125f is formed.

[0373] Next, as Figure 8C shown, an insulating film 127f that will become the insulating layer 127 later is formed on the inorganic insulating film 125f.

[0374] The substrate temperature during the formation of the inorganic insulating film 125f and the insulating film 127f is each preferably 60°C or higher, 80°C or higher, 100°C or higher, or 120°C or higher and 200°C or lower, 180°C or lower, 160°C or lower, 150°C or lower, or 140°C or lower.

[0375] As the inorganic insulating film 125f, it is preferable to form an insulating film with a thickness of 3 nm or more, 5 nm or more, or 10 nm or more and 200 nm or less, 150 nm or less, 100 nm or less, or 50 nm or less within the above substrate temperature range.

[0376] The inorganic insulating film 125f is preferably formed by the ALD method, for example. By using the ALD method, deposition damage can be reduced, and a film with high coverage can be deposited, so it is preferable. As the inorganic insulating film 125f, an alumina film is preferably formed by the ALD method, for example.

[0377] The insulating film 127f is preferably formed by the above wet deposition method. The insulating film 127f is preferably formed by spin coating using a photosensitive material, for example, and more specifically, it is preferably formed using a photosensitive resin composition containing an acrylic resin.

[0378] Next, exposure is performed to sensitize a part of the insulating film 127f with visible light or ultraviolet light. The insulating layer 127 is formed in a region between any two of the conductive layers 152R, 152G, and 152B and around the conductive layer 152C.

[0379] By means of the exposed region of the insulating film 127f, the width of the insulating layer 127 to be formed later can be controlled. In the present embodiment, processing is performed such that the insulating layer 127 has a portion overlapping the top surface of the conductive layer 151.

[0380] The light for exposure preferably has an i-line (wavelength 365 nm). In addition, the light for exposure may have at least one of a g-line (wavelength 436 nm) and an h-line (wavelength 405 nm).

[0381] Next, as Figure 9A shown, development is performed to remove the exposed region in the insulating film 127f to form the insulating layer 127a.

[0382] Next, as Figure 9B shown, an etching process is performed using the insulating layer 127a as a mask to remove a part of the inorganic insulating film 125f, thereby reducing the thickness of a part of the sacrificial layers 158R, 158G, and 158B. As a result, an inorganic insulating layer 125 is formed under the insulating layer 127a. In addition, the surfaces of the thin portions of the sacrificial layers 158R, 158G, and 158B are exposed. Note that hereinafter, the etching process using the insulating layer 127a as a mask is sometimes referred to as the first etching process.

[0383] The first etching process can be performed by dry etching or wet etching. When the inorganic insulating film 125f is deposited using the same material as the sacrificial layers 158R, 158G, and 158B, the first etching process can be performed at once, which is preferable.

[0384] When performing dry etching, a chlorine-based gas is preferably used. As the chlorine-based gas, Cl 2 、BCl 3 、SiCl 4 、and CCl 4 and the like, or a gas obtained by mixing two or more of the above can be used. In addition, one of oxygen gas, hydrogen gas, helium gas, and argon gas, or a gas obtained by mixing two or more of the above can be appropriately added to the above chlorine-based gas. By using dry etching, regions with a thin thickness of the sacrificial layers 158R, 158G, and 158B can be formed with excellent in-plane uniformity.

[0385] As a dry etching device, a dry etching device having a high-density plasma source can be used. As a dry etching device having a high-density plasma source, for example, an inductively coupled plasma (ICP: Inductively Coupled Plasma) etching device can be used. Alternatively, a capacitively coupled plasma (CCP: Capacitively Coupled Plasma) etching device including parallel plate electrodes can be used.

[0386] In addition, it is preferred to perform the first etching treatment by wet etching. By using the wet etching method, the damage to the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B can be reduced compared to the case of using the dry etching method. For example, an alkaline solution can be used for wet etching. For example, when wet etching an aluminum oxide film, an alkaline solution TMAH can be used. In addition, an acidic solution containing fluoride can also be used. In this case, wet etching can be performed in a glue coating manner. Note that when the inorganic insulating film 125f is deposited using the same material as the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B, the above-mentioned etching treatment can be performed at one time, so it is preferred.

[0387] In the first etching process, the sacrificial layers 158R, 158G, and 158B are not completely removed, and the etching process is stopped in a state where the thickness is reduced. In this way, by leaving the corresponding sacrificial layers 158R, 158G, and 158B on the organic compound layers 103R, 103G, and 103B, the organic compound layers 103R, 103G, and 103B can be prevented from being damaged in the subsequent process.

[0388] Next, the entire substrate is preferably exposed to visible light or ultraviolet light to irradiate the insulating layer 127a. The energy density of this exposure is preferably greater than 0 mJ / cm 2 And 800mJ / cm 2 Below, more preferably greater than 0 mJ / cm 2 And 500mJ / cm 2 By performing such exposure after development, the transparency of the insulating layer 127a can be improved. In addition, the substrate temperature required for heat treatment in a later step for deforming the insulating layer 127a into a tapered shape can be reduced.

[0389] Here, by providing an oxygen blocking insulating layer (for example, an aluminum oxide film) as the sacrificial layers 158R, 158G, and 158B, diffusion of oxygen into the organic compound layers 103R, 103G, and 103B can be reduced.

[0390] Next, a heat treatment (also referred to as post-baking) is performed. By performing the heat treatment, the insulating layer 127a can be deformed into the insulating layer 127 having a tapered shape on its side surface ( Figure 9C ). This heat treatment is performed at a temperature lower than the heat-resistant temperature of the organic compound layer. The heat treatment can be performed at a substrate temperature of 50°C or higher and 200°C or lower, preferably 60°C or higher and 150°C or lower, more preferably 70°C or higher and 130°C or lower. The heating atmosphere can be either an air atmosphere or an inert gas atmosphere. In addition, the heating atmosphere can be either an air atmosphere or a reduced-pressure atmosphere. Thereby, the adhesion between the insulating layer 127 and the inorganic insulating layer 125 can be improved, and the corrosion resistance of the insulating layer 127 can also be improved.

[0391] In the first etching process, by not completely removing the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B and leaving the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B in a state where their thicknesses are thinned, it is possible to prevent the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B from being damaged and deteriorated during this heat treatment. Thereby, the reliability of the light-emitting device can be improved.

[0392] Next, as Figure 10A shown, using the insulating layer 127 as a mask, an etching process is performed to remove a part of the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B. Thereby, openings are formed in each of the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B, and the top surfaces of the organic compound layer 103R, the organic compound layer 103G, the organic compound layer 103B, and the conductive layer 152C are exposed. Note that hereinafter, this etching process is sometimes referred to as the second etching process.

[0393] The end portion of the inorganic insulating layer 125 is covered by the insulating layer 127. In addition, Figure 10A an example is shown in which a part of the end portion of the sacrificial layer 158G (specifically, the tapered-shaped portion formed by the first etching process) is covered by the insulating layer 127 and the tapered-shaped portion formed by the second etching process is exposed.

[0394] In addition, it is preferable to perform the second etching process using wet etching. By using the wet etching method, the damage to the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B can be reduced compared to the case of using the dry etching method. For example, wet etching can be performed using an alkaline solution or an acidic solution. In order to prevent the organic compound layer 103 from dissolving, it is preferable to use an aqueous solution.

[0395] Next, as Figure 10BAs shown, a common electrode 155 is formed on the organic compound layer 103R, the organic compound layer 103G, the organic compound layer 103B, the conductive layer 152C, and the insulating layer 127. The common electrode 155 can be formed by a method such as a sputtering method or a vacuum evaporation method.

[0396] Next, as Figure 10C shown, a protective layer 131 is formed on the common electrode 155. The protective layer 131 can be formed by a method such as a vacuum evaporation method, a sputtering method, a CVD method, or an ALD method.

[0397] Next, the substrate 120 is bonded to the protective layer 131 using the resin layer 122, whereby a display device can be manufactured. As described above, in the method for manufacturing a display device according to one embodiment of the present invention, the insulating layer 156 is provided so as to include a region overlapping the side surface of the conductive layer 151, and the conductive layer 152 is formed so as to cover the conductive layer 151 and the insulating layer 156. Thereby, the yield of the display device can be improved, and the occurrence of defects can be suppressed.

[0398] As described above, in the method for manufacturing a display device according to one embodiment of the present invention, the island-shaped organic compound layer 103R, the island-shaped organic compound layer 103G, and the island-shaped organic compound layer 103B are not formed using a high-precision metal mask, but are formed by depositing a film on one surface and then processing it, so that the island-shaped layers can be formed with a uniform thickness. And a high-definition display device or a display device with a high aperture ratio can be realized. In addition, even if the definition or aperture ratio is high and the distance between sub-pixels is extremely short, it is possible to suppress the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B from contacting each other in adjacent sub-pixels. Therefore, it is possible to suppress the occurrence of leakage current between sub-pixels. Thereby, it is possible to prevent crosstalk and realize a display device with extremely high contrast. In addition, even for a display device including a tandem light-emitting device manufactured by a photolithography method, a display device with good characteristics can be provided.

[0399] Embodiment 5

[0400] In this embodiment, a display device according to one embodiment of the present invention will be described.

[0401] The display device of this embodiment can be a high-definition display device. Therefore, for example, the display device of this embodiment can be used as a display unit of information terminal devices (wearable devices) such as watch-type and bracelet-type, and a display unit of wearable devices that can be worn on the head such as VR devices such as head-mounted displays (HMDs) and glasses-type AR devices.

[0402] In addition, the display device of the present embodiment can be a high-resolution display device or a large display device. Therefore, for example, the display device of the present embodiment can be used as the display unit of the following devices: electronic devices with a large screen such as a television device, a desktop or notebook personal computer, a display for a computer, etc., a digital signage, and a large game machine such as a pachinko machine; a digital camera; a digital video camera; a digital photo frame; a mobile phone; a portable game machine; a portable information terminal; and a sound reproduction device.

[0403] [Display module]

[0404] Figure 11A A perspective view showing the display module 280. The display module 280 includes a display device 100A and an FPC 290. Note that the display device included in the display module 280 is not limited to the display device 100A, and can also be any one of the display devices 100B to 100E described later.

[0405] The display module 280 includes a substrate 291 and a substrate 292. The display module 280 includes a display portion 281. The display portion 281 is the image display area in the display module 280, and is an area where light from each pixel provided in the following pixel portion 284 can be seen.

[0406] Figure 11B It is a perspective schematic diagram of the structure on the side of the substrate 291. A circuit portion 282 is laminated on the substrate 291, a pixel circuit portion 283 is laminated on the circuit portion 282, and a pixel portion 284 is laminated on the pixel circuit portion 283. In addition, a terminal portion 285 for connecting to the FPC 290 is provided on a portion of the substrate 291 that does not overlap with the pixel portion 284. The terminal portion 285 and the circuit portion 282 are electrically connected through a wiring portion 286 composed of a plurality of wirings.

[0407] The pixel portion 284 includes a plurality of pixels 284a arranged periodically. Figure 11B An enlarged view of one pixel 284a is shown on the right side. The pixel 284a can adopt various structures described in the above embodiment.

[0408] The pixel circuit portion 283 includes a plurality of pixel circuits 283a arranged periodically.

[0409] One pixel circuit 283a controls the driving of a plurality of elements included in one pixel 284a.

[0410] The circuit portion 282 includes a circuit for driving each pixel circuit 283a of the pixel circuit portion 283. For example, it preferably includes one or both of a gate line driving circuit and a source line driving circuit. In addition, it may also have at least one of an arithmetic circuit, a storage circuit, and a power supply circuit, etc.

[0411] The FPC 290 is used as a wiring for supplying a video signal, a power potential, etc. from the outside to the circuit section 282. In addition, an IC can be mounted on the FPC 290.

[0412] The display module 280 may adopt a structure in which one or both of the pixel circuit section 283 and the circuit section 282 are laminated on the lower side of the pixel section 284, so that the display section 281 can have an extremely high aperture ratio (effective display area ratio).

[0413] The above-mentioned display module 280 has extremely high clarity, so it can be suitably used for VR devices such as HMDs or glasses-type AR devices. For example, in the structure of viewing the display section of the display module 280 through a lens, since the display module 280 has a display section 281 with extremely high clarity, even if the user magnifies the display section with the lens, pixels cannot be seen, and thus a display with a high sense of immersion can be achieved. In addition, the display module 280 is not limited to this, and can also be applied to electronic devices with a relatively small display section.

[0414] [Display device 100A]

[0415] Figure 12A The shown display device 100A includes a substrate 301, a light-emitting device 130R, a light-emitting device 130G, a light-emitting device 130B, a capacitor 240, and a transistor 310.

[0416] The substrate 301 corresponds to Figure 12A and Figure 12B the substrate 291 in

[0417] The transistor 310 is a transistor having a channel formation region in the substrate 301. As the substrate 301, for example, a semiconductor substrate such as a single-crystalline silicon substrate can be used. The transistor 310 includes a part of the substrate 301, a conductive layer 311, a low-resistance region 312, an insulating layer 313, and an insulating layer 314. The conductive layer 311 is used as a gate electrode. The insulating layer 313 is located between the substrate 301 and the conductive layer 311 and is used as a gate insulating layer. The low-resistance region 312 is a region in the substrate 301 doped with impurities and is used as a source or a drain. The insulating layer 314 covers the side surface of the conductive layer 311.

[0418] In addition, an element isolation layer 315 is provided in a manner of being embedded in the substrate 301 between two adjacent transistors 310.

[0419] The capacitor 240 includes a conductive layer 241, a conductive layer 245, and an insulating layer 243 therebetween. The conductive layer 241 is used as one electrode in the capacitor 240, the conductive layer 245 is used as the other electrode in the capacitor 240, and the insulating layer 243 is used as the dielectric of the capacitor 240.

[0420] The conductive layer 241 is disposed on the insulating layer 261 and embedded in the insulating layer 254. The conductive layer 241 is electrically connected to one of the source and drain of the transistor 310 through a plug 271 embedded in the insulating layer 261. The insulating layer 243 is disposed so as to cover the conductive layer 241. The conductive layer 245 is disposed in a region overlapping the conductive layer 241 with the insulating layer 243 therebetween.

[0421] An insulating layer 255 is disposed so as to cover the capacitor 240. An insulating layer 174 is disposed on the insulating layer 255, and an insulating layer 175 is disposed on the insulating layer 174. A light-emitting device 130R, a light-emitting device 130G, and a light-emitting device 130B are disposed on the insulating layer 175. An insulator is disposed in a region between adjacent light-emitting devices.

[0422] An insulating layer 156R is disposed so as to include a region overlapping the side surface of the conductive layer 151R, an insulating layer 156G is disposed so as to include a region overlapping the side surface of the conductive layer 151G, and an insulating layer 156B is disposed so as to include a region overlapping the side surface of the conductive layer 151B. In addition, a conductive layer 152R is disposed so as to cover the conductive layer 151R and the insulating layer 156R, a conductive layer 152G is disposed so as to cover the conductive layer 151G and the insulating layer 156G, and a conductive layer 152B is disposed so as to cover the conductive layer 151B and the insulating layer 156B. A sacrificial layer 158R is located on the organic compound layer 103R, a sacrificial layer 158G is located on the organic compound layer 103G, and a sacrificial layer 158B is located on the organic compound layer 103B.

[0423] The conductive layers 151R, 151G, and 151B are electrically connected to one of the source and drain of the transistor 310 through plugs 256 embedded in the insulating layers 243, 255, 174, and 175, the conductive layer 241 embedded in the insulating layer 254, and the plug 271 embedded in the insulating layer 261. Various conductive materials can be used for the plugs.

[0424] In addition, a protective layer 131 is disposed on the light-emitting devices 130R, 130G, and 130B. A substrate 120 is bonded to the protective layer 131 with a resin layer 122. Details of the components from the light-emitting devices 130 to the substrate 120 can be referred to in Embodiment 4. The substrate 120 corresponds to Figure 11A the substrate 292.

[0425] Figure 12B shows Figure 12A a modified example of the display device 100A shown. Figure 12B The display device shown includes a coloring layer 132R, a coloring layer 132G, and a coloring layer 132B, and the light-emitting device 130 has an area overlapping one of the coloring layer 132R, the coloring layer 132G, and the coloring layer 132B. Among Figure 12B the display devices shown, the light-emitting device 130 can emit white light, for example. In addition, for example, the coloring layer 132R, the coloring layer 132G, and the coloring layer 132B can transmit red light, green light, and blue light, respectively.

[0426] [Display device 100B]

[0427] Figure 13 A perspective view showing the display device 100B, Figure 14 A cross-sectional view showing the display device 100C.

[0428] The display device 100B has a structure in which a bonding substrate 352 and a substrate 351 are bonded. Among Figure 13 them, the substrate 352 is indicated by a dashed line.

[0429] The display device 100B includes a pixel portion 177, a connection portion 140, a circuit 356, wirings 355, and the like. Figure 13 An example in which an IC 354 and an FPC 353 are mounted on the display device 100B is shown. Therefore, Figure 13 the structure shown can also be referred to as a display module including the display device 100B, an IC (integrated circuit), and an FPC. Here, the substrate of the display device on which a connector such as an FPC is mounted or the substrate on which an IC is mounted is referred to as a display module.

[0430] The connection portion 140 is provided outside the pixel portion 177. The connection portion 140 can be one or more. In the connection portion 140, a common electrode of the light-emitting device is electrically connected to a conductive layer, and a potential can be supplied to the common electrode.

[0431] As the circuit 356, for example, a scan line driving circuit can be used.

[0432] The wiring 355 has a function of supplying signals and power to the pixel portion 177 and the circuit 356. The signals and power are input to the wiring 355 from the outside via the FPC 353 or input to the wiring 355 from the IC 354.

[0433] Figure 13An example of providing IC354 on substrate 351 by COG (Chip On Glass) method or COF (Chip On Film) method is shown. As IC354, for example, an IC including a scanning line driving circuit or a signal line driving circuit can be used. Note that the display device 100B and the display module do not necessarily have to be provided with an IC. In addition, for example, the IC can also be mounted on an FPC by using a COF method.

[0434] Figure 14 As the display device 100C, Figure 13 FIG. 1 is an example of a cross section of a portion of the region including the FPC 353 , a portion of the circuit 356 , a portion of the pixel portion 177 , a portion of the connection portion 140 , and a portion of the region including the end portion of the display device 100B in FIG.

[0435] [Display device 100C]

[0436] Figure 14 The display device 100C shown includes a transistor 201 , a transistor 205 , a light-emitting device 130R that emits red light, a light-emitting device 130G that emits green light, a light-emitting device 130B that emits blue light, and the like between a substrate 351 and a substrate 352 .

[0437] For details of the light emitting device 130R, the light emitting device 130G, and the light emitting device 130B, reference may be made to Embodiment 4.

[0438] The light emitting device 130R includes a conductive layer 224R, a conductive layer 151R on the conductive layer 224R, and a conductive layer 152R on the conductive layer 151R. The light emitting device 130G includes a conductive layer 224G, a conductive layer 151G on the conductive layer 224G, and a conductive layer 152G on the conductive layer 151G. The light emitting device 130B includes a conductive layer 224B, a conductive layer 151B on the conductive layer 224B, and a conductive layer 152B on the conductive layer 151B.

[0439] The conductive layer 224R is connected to the conductive layer 222b included in the transistor 205 through an opening provided in the insulating layer 214. An end of the conductive layer 151R is located outside an end of the conductive layer 224R. The insulating layer 156R is provided so as to include a region in contact with a side surface of the conductive layer 151R, and the conductive layer 152R is provided so as to cover the conductive layer 151R and the insulating layer 156R.

[0440] The conductive layer 224G, conductive layer 151G, conductive layer 152G, insulating layer 156G in the light-emitting device 130G, the conductive layer 224B, conductive layer 151B, conductive layer 152B, insulating layer 156B in the light-emitting device 130B, and the conductive layer 224R, conductive layer 151R, conductive layer 152R, insulating layer 156R in the light-emitting device 130R are the same, so detailed description is omitted.

[0441] In the conductive layer 224R, conductive layer 224G, and conductive layer 224B, recesses are formed in a manner of covering the openings provided in the insulating layer 214. The recesses are filled with the layer 128.

[0442] The layer 128 has a function of planarizing by filling the recesses of the conductive layer 224R, conductive layer 224G, and conductive layer 224B. On the conductive layer 224R, conductive layer 224G, conductive layer 224B, and layer 128, conductive layers 151R, 151G, and 151B electrically connected to the conductive layer 224R, conductive layer 224G, and conductive layer 224B are provided. Therefore, the regions overlapping with the recesses of the conductive layer 224R, conductive layer 224G, and conductive layer 224B can also be used as light-emitting regions, and the aperture ratio of the pixel can be increased.

[0443] The layer 128 can also be an insulating layer or a conductive layer. The layer 128 can appropriately use various inorganic insulating materials, organic insulating materials, and conductive materials. In particular, the layer 128 is preferably formed using an insulating material, and more preferably formed using an organic insulating material. For example, the layer 128 can use the organic insulating material that can be used for the insulating layer 127 as described above.

[0444] A protective layer 131 is provided on the light-emitting device 130R, light-emitting device 130G, and light-emitting device 130B. The protective layer 131 and the substrate 352 are bonded by the adhesive layer 142. The substrate 352 is provided with a light-shielding layer 157. The light-emitting device 130 can be sealed using a solid-sealing structure or a hollow-sealing structure, etc. In Figure 14 this case, the space between the substrate 352 and the substrate 351 is filled with the adhesive layer 142, that is, a solid-sealing structure is adopted. Alternatively, the space can also be filled with an inert gas (such as nitrogen or argon), that is, a hollow-sealing structure is adopted. At this time, the adhesive layer 142 can also be provided in a manner that does not overlap with the light-emitting device. In addition, the space can also be filled with a resin different from the adhesive layer 142 provided in a frame shape.

[0445] Figure 14An example is shown below: The connection part 140 includes a conductive layer 224C obtained by processing a conductive film the same as the conductive layers 224R, 224G, and 224B, a conductive layer 151C obtained by processing a conductive film the same as the conductive layers 151R, 151G, and 151B, and a conductive layer 152C obtained by processing a conductive film the same as the conductive layers 152R, 152G, and 152B. In addition, Figure 14 An example is shown in which the insulating layer 156C is provided in a manner that includes a region overlapping with the side surface of the conductive layer 151C.

[0446] The display device 100C is a top emission structure display device. The light-emitting device emits light to the side of the substrate 352. The substrate 352 is preferably made of a material with high visible light transmittance. The pixel electrode contains a material that reflects visible light, and the counter electrode (common electrode 155) contains a material that transmits visible light.

[0447] An insulating layer 211, an insulating layer 213, an insulating layer 215, and an insulating layer 214 are sequentially provided on the substrate 351. A part of the insulating layer 211 is used as the gate insulating layer of each transistor. A part of the insulating layer 213 is used as the gate insulating layer of each transistor. The insulating layer 215 is provided so as to cover the transistor. The insulating layer 214 is provided so as to cover the transistor and is used as a planarization layer. In addition, there is no particular limitation on the number of gate insulating layers and the number of insulating layers covering the transistor, and it can be either one or two or more.

[0448] Preferably, an inorganic insulating film is used as the insulating layer 211, the insulating layer 213, and the insulating layer 215.

[0449] Preferably, an organic insulating layer is used as the insulating layer 214 serving as the planarization layer.

[0450] The transistors 201 and 205 include: a conductive layer 221 serving as a gate; an insulating layer 211 serving as a gate insulating layer; conductive layers 222a and 222b serving as source and drain electrodes; a semiconductor layer 231; an insulating layer 213 serving as a gate insulating layer; and a conductive layer 223 serving as a gate.

[0451] A connection portion 204 is provided in a region of the substrate 351 that does not overlap with the substrate 352. In the connection portion 204, a source electrode or a drain electrode of the transistor 201 is electrically connected to the FPC 353 through the conductive layer 166 and the connection layer 242. The following example is shown: The conductive layer 166 has a stacked structure of a conductive film obtained by processing a conductive film identical to the conductive layers 224R, 224G, and 224B, a conductive film obtained by processing a conductive film identical to the conductive layers 151R, 151G, and 151B, and a conductive film obtained by processing a conductive film identical to the conductive layers 152R, 152G, and 152B. The conductive layer 166 is exposed on the top surface of the connection portion 204. Therefore, the connection portion 204 can be electrically connected to the FPC 353 through the connection layer 242.

[0452] Preferably, a light-shielding layer 157 is provided on the surface of the substrate 352 on the side of the substrate 351. The light-shielding layer 157 can be provided between adjacent light-emitting devices, in the connection portion 140, the circuit 356, etc. In addition, various optical members can be arranged outside the substrate 352.

[0453] Each of the substrate 351 and the substrate 352 can adopt a material that can be used for the substrate 120.

[0454] As the adhesive layer 142, a material that can be used for the resin layer 122 can be used.

[0455] As the connection layer 242, an anisotropic conductive film (ACF: Anisotropic Conductive Film), an anisotropic conductive paste (ACP: Anisotropic Conductive Paste), or the like can be used.

[0456] [Display device 100D]

[0457] Figure 15 The shown display device 100D and Figure 14 The main difference from the shown display device 100C is that the display device 100D is a bottom-emission structure display device.

[0458] The light-emitting device emits light to the side of the substrate 351. The substrate 351 is preferably made of a material with high transparency to visible light. On the other hand, there is no limitation on the light transmittance of the material used for the substrate 352.

[0459] Preferably, a light-shielding layer 317 is formed between the substrate 351 and the transistor 201 and between the substrate 351 and the transistor 205. Figure 15 An example is shown in which a light-shielding layer 317 is provided on the substrate 351, an insulating layer 153 is provided on the light-shielding layer 317, and transistors 201, 205, etc. are provided on the insulating layer 153.

[0460] The light-emitting device 130R includes a conductive layer 112R, a conductive layer 126R on the conductive layer 112R, and a conductive layer 129R on the conductive layer 126R.

[0461] The light-emitting device 130B includes a conductive layer 112B, a conductive layer 126B on the conductive layer 112B, and a conductive layer 129B on the conductive layer 126B.

[0462] The conductive layers 112R, 112B, 126R, 126B, 129R, and 129B all use materials with high transparency to visible light. As the second electrode 102, a material that reflects visible light is preferably used.

[0463] Note that although Figure 15 the light-emitting device 130G is not shown in the figure, the light-emitting device 130G is also provided.

[0464] In addition, Figure 15 examples such as those showing that the top surface of the layer 128 has a flat portion are shown, but the shape of the layer 128 is not particularly limited.

[0465] [Display device 100D2]

[0466] Figures 16A to 16C The display device 100D2 shown is an example of a display device with a bottom emission structure different from that of Figure 15 the display device 100D shown. The difference between the display device 100D2 and the display device 100D is that the former includes an organic resin layer 180. Note that in the drawings, the symbols of the same components as those in Figure 15 may sometimes be omitted, and the detailed content can be referred to the description in Figure 15 .

[0467] In addition, Figure 16B a top surface layout of the pixel 178 (pixel 178a and pixel 178b) including the sub-pixels 110 (sub-pixel 110R, sub-pixel 110G, sub-pixel 110B, sub-pixel 110W) is shown, Figure 16C a top view of the organic resin layer 180 in the region where the sub-pixels 110R and 110G included in the pixel 178 are formed is shown. In addition, the width 110Rw in the light-emitting region of the sub-pixel 110R is between the light-shielding layers 317 and 317.

[0468] As Figure 16A shown, the organic resin layer 180 is provided on the insulating layer 214. As Figure 16A the region surrounded by the dotted line in Figure 16CAs shown, the organic resin layer 180 includes concave portions 181 (concave portion 181a, concave portion 181b) having a curved surface at least in the region where sub-pixels are formed. Additionally, the concave portion 181 may be provided outside the light-emitting region like the concave portion 181c. By providing the concave portion 181c, the light generated in the region overlapping the light-shielding layer 317 or the light entering the region overlapping the light-shielding layer 317 is refracted, and it can be extracted from the light-emitting region, thereby improving the light-emitting efficiency.

[0469] The plurality of concave portions 181 may also be formed in a matrix shape. The concave portion 181a and the concave portion 181b may be arranged to be in contact with each other or may be arranged to have a flat surface therebetween.

[0470] In addition, although Figures 16A to 16C it is shown that the top surface shape of the concave portion is hexagonal ( Figure 16C ) and the cross-sectional shape is semi-circular ( Figure 16A ), other shapes may be adopted as needed. For example, as the top surface shape of the concave portion, polygons such as triangles, quadrilaterals (including rectangles, squares), pentagons, etc., shapes in which the corners of the above polygons are rounded, ellipses, or circles, etc., can be cited.

[0471] As the organic resin layer 180, an insulating layer containing an organic material can be used. For example, as the organic resin layer 180, acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimide amide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenolic resin, and precursors of the above resins, etc., can be used. In addition, as the organic resin layer 180, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerol, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin can also be used.

[0472] In addition, as the organic resin layer 180, a photosensitive resin can be used. As the photosensitive resin, a photoresist can also be used. The photosensitive resin can use a positive-type material or a negative-type material.

[0473] The organic resin layer 180 may also contain a material that absorbs visible light. For example, the organic resin layer 180 itself may be composed of a material that absorbs visible light, or the organic resin layer 180 may contain a pigment that absorbs visible light. As the organic resin layer 180, for example, the following resins can be used: a resin that can be used as a color filter that allows red light, blue light, or green light to pass through and absorbs light of other colors; or a resin that contains carbon black as a pigment and is used as a black matrix; etc.

[0474] In addition, a first electrode 101 (first electrodes 101R and 101W) is provided on the organic resin layer 180, and an organic compound layer 103 is provided on the first electrode 101. The ends of the first electrode 101 and the organic compound layer 103 may also be covered by an insulating layer 127.

[0475] In addition, the first electrode 101 formed on the organic resin layer 180 has a recess in the same manner as the recess of the organic resin layer 180. The organic compound layer 103 formed on the first electrode 101 has a recess in the same manner as the recess of the first electrode 101. The common layer 104 formed on the organic compound layer 103 has a recess in the same manner as the recess of the organic compound layer 103. Further, the second electrode 102 formed on the common layer 104 has a recess in the same manner as the recess of the common layer 104. In other words, the recesses of the organic resin layer 180, the first electrode 101, the organic compound layer 103, the common layer 104, and the second electrode 102 overlap each other.

[0476] In addition, a common layer 104 is provided on the organic compound layer 103 and the insulating layer 127, and a second electrode 102 is provided on the common layer 104. A protective layer 131 is provided on the second electrode 102 and is bonded to the substrate 352 via an adhesive layer 142.

[0477] Note that, although Figures 16A to 16C the light-emitting devices 130G and 130B are not shown, the light-emitting devices 130G and 130B are provided.

[0478] In a light-emitting device according to one embodiment of the present invention including the above-described organic resin layer 180, as described in Embodiment 1, an organic compound represented by the general formula (Gh1) is included in the organic compound layer 103. Due to the inseparable action of the organic resin layer 180 and the organic semiconductor device using the organic compound of the present invention, an organic semiconductor device with high luminous efficiency can be provided, and an organic semiconductor device with high reliability, low driving voltage, and low power consumption can be provided.

[0479] [Display device 100E]

[0480] Figure 17 The display device 100E shown is Figure 14 a modified example of the display device 100C shown. The main difference between the display device 100E and the display device 100C is that the former includes a coloring layer 132R, a coloring layer 132G, and a coloring layer 132B.

[0481] In the display device 100E, the light-emitting device 130 has a region overlapping one of the color layers 132R, 132G, and 132B. The color layers 132R, 132G, and 132B may be provided on the surface of the substrate 351 on the side of the substrate 352. The ends of the color layer 132R, the ends of the color layer 132G, and the ends of the color layer 132B may overlap the light-shielding layer 157.

[0482] In the display device 100E, the light-emitting device 130 can emit white light, for example. Additionally, for example, the color layer 132R, the color layer 132G, and the color layer 132B can transmit red light, green light, and blue light, respectively. Additionally, the display device 100E may also adopt a structure in which the color layers 132R, 132G, and 132B are provided between the protective layer 131 and the adhesive layer 142.

[0483] [Display device 100E2]

[0484] Figures 18A to 18C The shown display device 100E2 is Figure 17 a modified example of the shown display device 100E, which includes microlenses 182 on the color layers 132R, 132G, and 132B. Note that in the drawings, the symbols of the same components as those in Figure 17 may sometimes be omitted, and the detailed content can be referred to Figure 17 for the description.

[0485] Additionally, Figure 18B shows the top view layout of the pixels 178 (pixels 178a and 178b) including the sub-pixels 110 (sub-pixels 110R, 110G, and 110B), Figure 18C and shows a plan view of the microlenses 182 in the region where the sub-pixels 110R and 110G included in the pixel 178 are formed. Note that the region where the common electrode 155 contacts the organic compound layer 103 is the width 110Gw in the light-emitting region of the sub-pixel 110G.

[0486] In Figure 18A the shown display device 100E2, a planarization film 143 is provided on the protective layer 131, and the color layers 132R, 132G, and 132B are provided on the planarization film 144. The planarization film 144 is provided so as to cover the color layers 132R, 132G, and 132B. The microlenses 182 are provided on the planarization film 144.

[0487] Additionally, as Figure 18C shown, it is preferable to provide the microlenses 182 for each sub-pixel in the region where the sub-pixels are formed.

[0488] Note that in Figure 18C the top surface of the microlens 182 has a hexagonal shape, but other shapes may be adopted as needed. For example, as the top surface shape of the recess, polygons such as triangles, quadrilaterals (including rectangles and squares), pentagons, etc., shapes in which the corners of the above polygons are rounded, ellipses or circles, etc. can be cited.

[0489] The microlens 182 can be formed using the same material as the organic resin layer 180.

[0490] In the light-emitting device according to one embodiment of the present invention including the microlens 182, as shown in Embodiment 1, the organic compound represented by the general formula (Gh1) is contained in the organic compound layer 103. Due to the inseparable effect of the microlens 182 and the organic semiconductor device using the organic compound of the present invention, an organic semiconductor device with high luminous efficiency can be provided, and an organic semiconductor device suitable for a portable display with high reliability, low driving voltage, and low power consumption can be provided.

[0491] This embodiment can be appropriately combined with other embodiments or examples. In addition, in this specification, when multiple structural examples are shown in one embodiment, the structural examples can be appropriately combined.

[0492] Embodiment 6

[0493] In this embodiment, an electronic device according to one embodiment of the present invention will be described.

[0494] The electronic device of this embodiment includes a display device according to one embodiment of the present invention in the display unit. The display device according to one embodiment of the present invention has low power consumption and high reliability. Therefore, it can be used in the display units of various electronic devices.

[0495] As the electronic device, for example, in addition to electronic devices with relatively large screens such as television sets, desktop or notebook personal computers, monitors for computers, digital signage, large game machines such as pachinko machines, etc., digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, portable information terminals, sound reproduction devices, etc. can also be cited.

[0496] Refer to Figures 19A to 19D to illustrate an example of a wearable device that can be worn on the head.

[0497] Figure 19A The electronic device 700A shown and Figure 19B the electronic device 700B shown both include a pair of display panels 751, a pair of outer casings 721, a communication unit (not shown), a pair of mounting portions 723, a control unit (not shown), an imaging unit (not shown), a pair of optical members 753, a frame 757, and a pair of nose pads 758.

[0498] The display panel 751 can be a display device according to one embodiment of the present invention. Thus, an electronic device with high reliability can be realized.

[0499] Both the electronic device 700A and the electronic device 700B can project the image displayed on the display panel 751 onto the display area 756 in the optical member 753. Since the optical member 753 has light transmissivity, the user can see the image displayed in the display area overlapping with the transmitted image seen through the optical member 753.

[0500] The electronic device 700A and the electronic device 700B may also be provided with a camera capable of photographing the front as an imaging unit. In addition, by providing an acceleration sensor such as a gyro sensor in the electronic device 700A and the electronic device 700B, the user's head orientation can be detected and the image corresponding to the direction can be displayed on the display area 756.

[0501] The communication unit has a wireless communication device, and an image signal can be supplied through this wireless communication device, for example. In addition, instead of or in addition to the wireless communication device, a connector capable of connecting a cable for supplying an image signal and a power potential may be included.

[0502] In addition, the electronic device 700A and the electronic device 700B are provided with a battery and can be charged in one or both of a wireless manner and a wired manner.

[0503] The housing 721 may also be provided with a touch sensor module.

[0504] As the touch sensor module, various touch sensors can be used. For example, various methods such as a capacitive method, a resistive film method, an infrared method, an electromagnetic induction method, a surface acoustic wave method, or an optical method can be adopted. In particular, it is preferable to apply a capacitive method or an optical method sensor to the touch sensor module.

[0505] Figure 19C The illustrated electronic device 800A and Figure 19D The illustrated electronic device 800B both include a pair of display units 820, a housing 821, a communication unit 822, a pair of mounting units 823, a control unit 824, a pair of imaging units 825, and a pair of lenses 832.

[0506] The display unit 820 can be a display device according to one embodiment of the present invention. Thus, an electronic device with high reliability can be realized.

[0507] The display unit 820 is disposed at a position visible through the lens 832 inside the housing 821. Further, by displaying different images on each of the pair of display units 820, three-dimensional display using parallax can be performed.

[0508] The electronic device 800A and the electronic device 800B preferably have a mechanism in which the left and right positions of the lens 832 and the display unit 820 can be adjusted so that the lens 832 and the display unit 820 are positioned at the most suitable positions according to the position of the user's eyes.

[0509] The user can wear the electronic device 800A or the electronic device 800B on the head using the mounting unit 823.

[0510] The imaging unit 825 has a function of acquiring external information. The data acquired by the imaging unit 825 can be output to the display unit 820. An image sensor can be used in the imaging unit 825. Further, a plurality of cameras may be provided to be able to correspond to various perspectives such as telephoto and wide angle.

[0511] The electronic device 800A may also include a vibration mechanism that serves as a bone conduction headphone.

[0512] The electronic device 800A and the electronic device 800B may both include input terminals. A cable for supplying an image signal from an image output device or the like and power for charging a battery provided in the electronic device can be connected to the input terminals.

[0513] The electronic device according to one aspect of the present invention may also have a function of performing wireless communication with the headphone 750.

[0514] Further, the electronic device may also include a headphone unit. Figure 19B The illustrated electronic device 700B includes a headphone unit 727. A part of the wiring connecting the headphone unit 727 and the control unit may also be disposed inside the housing 721 or the mounting unit 723.

[0515] Similarly, Figure 19D The illustrated electronic device 800B includes a headphone unit 827. For example, a structure in which the headphone unit 827 and the control unit 824 are connected in a wired manner may be employed.

[0516] Thus, as the electronic device according to one aspect of the present invention, both the glasses type (such as the electronic device 700A and the electronic device 700B) and the goggle type (such as the electronic device 800A and the electronic device 800B) are preferable.

[0517] Figure 20A The illustrated electronic device 6500 is a portable information terminal device that can be used as a smartphone.

[0518] The electronic device 6500 includes a housing 6501, a display unit 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, a light source 6508, etc. The display unit 6502 has a touch panel function.

[0519] The display unit 6502 can use the display device of one mode of the present invention. Thus, an electronic device with high reliability can be realized.

[0520] Figure 20B It is a schematic cross-sectional view of an end portion on the microphone 6506 side including the housing 6501.

[0521] A protective member 6510 with light transmissivity is provided on the display surface side of the housing 6501, and a display panel 6511, an optical member 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are provided in the space surrounded by the housing 6501 and the protective member 6510.

[0522] The display panel 6511, the optical member 6512, and the touch sensor panel 6513 are fixed to the protective member 6510 using an adhesive layer (not shown).

[0523] In a region outside the display unit 6502, a part of the display panel 6511 is folded, and an FPC 6515 is connected to the folded part. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to a terminal provided on the printed circuit board 6517.

[0524] The display panel 6511 can use the display device of one mode of the present invention. Thus, an extremely lightweight electronic device can be realized. In addition, since the display panel 6511 is extremely thin, a large-capacity battery 6518 can be installed while suppressing the thickness of the electronic device. In addition, by folding a part of the display panel 6511 to provide a connection portion with the FPC 6515 on the back surface of the pixel portion, an electronic device with a narrow bezel can be realized.

[0525] Figure 20C An example of a television device is shown. In the television device 7100, a display unit 7000 is assembled in a housing 7171. A structure in which the housing 7171 is supported by a bracket 7173 is shown here.

[0526] The display unit 7000 can use the display device of one mode of the present invention. Thus, an electronic device with high reliability can be realized.

[0527] The operation of the television device 7100 shown can be performed by using the operation switch provided in the housing 7171 and an additional remote operation machine 7151. Figure 20C The operation of the television device 7100 shown.

[0528] Figure 20D An example of a notebook personal computer is shown. The notebook personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, an external connection port 7214, etc. A display unit 7000 is assembled in the housing 7211.

[0529] The display unit 7000 can use the display device of one mode of the present invention. Thereby, an electronic device with high reliability can be realized.

[0530] Figure 20E and Figure 20F An example of a digital sign is shown.

[0531] Figure 20E The digital sign 7300 shown includes a housing 7301, a display unit 7000, a speaker 7303, etc. In addition, it may further include an LED lamp, operation keys (including a power switch or an operation switch), connection terminals, various sensors, a microphone, etc.

[0532] Figure 20F A digital sign 7400 provided on a cylindrical column 7401 is shown. The digital sign 7400 includes a display unit 7000 provided along the curved surface of the column 7401.

[0533] In Figure 20E and Figure 20F , the display device of one mode of the present invention can be used for the display unit 7000. Thereby, an electronic device with high reliability can be realized.

[0534] The larger the display unit 7000 is, the more information can be provided at one time. The larger the display unit 7000 is, the more likely it is to attract people's attention. For example, the advertising effect can be improved.

[0535] As Figure 20E and Figure 20F shown, the digital sign 7300 or the digital sign 7400 can preferably be linked with an information terminal device 7311 such as a smart phone carried by a user or an information terminal device 7411 through wireless communication.

[0536] Figures 21A to 21G The electronic device shown includes a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), connection terminals 9006, a sensor 9007 (the sensor has a function of measuring the following factors: force, displacement, position, speed, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, inclination, vibration, odor or infrared ray), a microphone 9008, etc.

[0537] Figures 21A to 21G The electronic device shown has various functions. For example, it can have the following functions: the function of displaying various information (such as still images, moving images, and text images) on the display unit; the function of a touch panel; the function of displaying a calendar, date, or time, etc.; the function of controlling processing by using various software (programs); the function of performing wireless communication; the function of reading and processing programs or data stored in a storage medium; etc.

[0538] Below, the Figures 21A to 21G electronic device shown will be described in detail.

[0539] Figure 21A is a perspective view showing a portable information terminal 9171. The portable information terminal 9171 can be used as a smart phone, for example. Note that in the portable information terminal 9171, a speaker 9003, a connection terminal 9006, a sensor 9007, etc. can also be provided. In addition, as the portable information terminal 9171, text or image information can be displayed on its multiple faces. In Figure 21A an example of displaying three icons 9050 is shown. In addition, information 9051 shown as a dotted rectangle can be displayed on other faces of the display unit 9001. As an example of the information 9051, information such as a prompt for receiving an e-mail, SNS, phone call, etc.; the title of an e-mail or SNS, etc.; the sender's name of an e-mail or SNS, etc.; date; time; battery level; and radio wave intensity, etc. can be cited. Or, an icon 9050, etc. can be displayed at the position where the information 9051 is displayed.

[0540] Figure 21B is a perspective view showing a portable information terminal 9172. The portable information terminal 9172 has the function of displaying information on more than three faces of the display unit 9001. Here, an example of information 9052, information 9053, and information 9054 being displayed on different faces respectively is shown. For example, in a state where the portable information terminal 9172 is placed in an upper body pocket, the user can confirm the information 9053 displayed at a position seen from above the portable information terminal 9172.

[0541] Figure 21C is a perspective view showing a tablet terminal 9173. The tablet terminal 9173 can execute various application software such as a mobile phone, e-mail, reading and editing of articles, playing music, network communication, computer games, etc., for example. The tablet terminal 9173 includes a display unit 9001, a camera 9002, a microphone 9008, and a speaker 9003 on the front surface of the housing 9000, and includes operation keys 9005 used as operation buttons on the left side surface of the housing 9000 and connection terminals 9006 on the bottom surface.

[0542] Figure 21D This is a perspective view showing a wristwatch-type portable information terminal 9200. The portable information terminal 9200 can be used as, for example, a smartwatch (registered trademark). In addition, the display surface of the display unit 9001 is curved, and display can be performed along the curved display surface. Further, the portable information terminal 9200 can perform hands-free calling, for example, by communicating with a headset capable of wireless communication. Further, by using the connection terminal 9006, the portable information terminal 9200 can perform data transmission with other information terminals or be charged. Charging can also be performed by wireless power supply.

[0543] Figures 21E to 21G This is a perspective view showing a foldable portable information terminal 9201. In addition, Figure 21E This is a perspective view of the state in which the portable information terminal 9201 is unfolded, Figure 21G This is a perspective view of the folded state, Figure 21F This is from Figure 21E this state and Figure 21G this state, and is a perspective view of an intermediate state when converting from one to the other. The portable information terminal 9201 has good portability in the folded state, and has strong display browsability in the unfolded state because it has a large seamless display area. The display unit 9001 included in the portable information terminal 9201 is supported by three housings 9000 connected by a hinge 9055. The display unit 9001 can be curved, for example, in a range where the radius of curvature is 0.1 mm or more and 150 mm or less.

[0544] This embodiment can be appropriately combined with other embodiments or examples. Further, in this specification, in the case where a plurality of structural examples are shown in one embodiment, the structural examples can be appropriately combined.

[0545] Example 1

[0546] In this example, the manufacturing methods and characteristics of a light-emitting device 1 of one aspect of the present invention and comparative light-emitting devices 1-1 to 1-3 for comparison are described in detail. The following shows the structural formulas of the main compounds used for the light-emitting device 1 and the comparative light-emitting devices 1-1 to 1-3.

[0547] [Chemical formula 4]

[0548]

[0549] (Manufacturing method of the light-emitting device 1)

[0550] First, on a glass substrate, indium tin oxide (ITSO) containing silicon oxide is laminated to a thickness of 70 nm by sputtering, thereby forming a first electrode 101 with a size of 2 mm × 2 mm. Additionally, the first electrode 101 is used as an anode.

[0551] Next, as a pretreatment for forming a light-emitting device on the substrate, the surface of the substrate is washed with water.

[0552] Then, the substrate is placed in a vacuum evaporation apparatus whose internal pressure is reduced to about 1 × 10 -4 Pa, and in the heating chamber inside the vacuum evaporation apparatus, vacuum baking is performed at a temperature of 170 °C for 30 minutes, and then the substrate is cooled for about 30 minutes.

[0553] Next, the substrate is fixed on a bracket inside the vacuum evaporation apparatus with the surface on which the first electrode 101 is formed facing downward. On the inorganic insulating film and the first electrode 101, co-evaporation is performed by evaporation method with N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf) shown in the above structural formula (i) and an electron acceptor material (OCHD-003) containing fluorine with a molecular weight of 672 at a weight ratio of 1:0.1 and a thickness of 10 nm, thereby forming a hole injection layer 111.

[0554] BBABnf is evaporated on the hole injection layer 111 to a thickness of 30 nm to form a first hole transport layer, and then 9-[3-(triphenylsilyl)phenyl]-3,9'-bi-9H-carbazole (abbreviation: PSiCzCz) shown in the above structural formula (ii) is evaporated to a thickness of 5 nm to form a second hole transport layer, thereby forming a hole transport layer 112. Note that the second hole transport layer is also used as an electron blocking layer.

[0555] Next, on the hole transport layer 112, 9,9'-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole-1,2,3,4,5,6,7,8,1',2',3',4',5',6',7',8'-d 16 )(abbreviation: SiTrzCz2-d16): 9-[3-(triphenylsilyl)phenyl]-3,9'-(bi-9H-carbazole-d 15)(Abbreviation: PSiCzCz-d15): Co-evaporation is performed in such a way that the weight ratio of (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazol-1-yl-2-ylidene-κC2]phenoxy-κC2}-9-(4-tert-butyl-2-pyridyl-κN)carbazole-2,1-diyl-κC1)platinum(II) (abbreviation: PtON-TBBI) shown in the above structural formula (v) is 0.435:0.435:0.13 and the thickness is 35 nm to form the light-emitting layer 113.

[0556] Then, 2-phenyl-4,6-bis[3-(triphenylsilyl)phenyl]-1,3,5-triazine (abbreviation: mSiTrz) shown in the above structural formula (vi) is evaporated in such a way that the thickness is 5 nm to form the first electron transport layer. Then, mSiTrz and lithium 8-hydroxyquinolate (abbreviation: Liq) shown in the above structural formula (vii) are co-evaporated in such a way that the weight ratio is 1:1 and the thickness is 20 nm to form the second electron transport layer, thereby forming the electron transport layer 114.

[0557] Next, lithium fluoride (LiF) is evaporated in such a way that the thickness is 1 nm to form the electron injection layer 115, and then aluminum (Al) is evaporated in such a way that the thickness is 200 nm, thereby forming the second electrode 102.

[0558] Next, in a glove box under a nitrogen atmosphere, a sealing treatment is performed using a glass substrate in such a way that the light-emitting device is not exposed to the atmosphere (applying a UV-curable sealing material around the element, performing a treatment of irradiating only the sealing material with UV without irradiating the light-emitting device with UV, and performing a heat treatment at 80 °C for 1 hour at atmospheric pressure), thereby forming the light-emitting device 1.

[0559] (Manufacturing method of Comparative Light-Emitting Device 1-1)

[0560] In Comparative Light-Emitting Device 1-1, 9,9’-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole) (abbreviation: SiTrzCz2) shown in the above structural formula (viii) is used instead of SiTrzCz2-d16 and PSiCzCz is used instead of PSiCzCz-d15, and it is manufactured in the same manner as the light-emitting device 1 except for this.

[0561] (Manufacturing method of Comparative Light-Emitting Device 1-2)

[0562] In Comparative Light-Emitting Device 1-2, PSiCzCz is used instead of PSiCzCz-d15 in the light-emitting device 1, and it is manufactured in the same manner as the light-emitting device 1 except for this.

[0563] (Manufacturing method of Comparative Light-Emitting Device 1-3)

[0564] In Comparative Light-Emitting Devices 1-3, SiTrzCz2 was used in place of SiTrzCz2-d16 in Light-Emitting Device 1, and other than that, they were fabricated in the same manner as Light-Emitting Device 1.

[0565] The device structures of Light-Emitting Device 1 and Comparative Light-Emitting Devices 1-1 to 1-3 are shown below.

[0566] [Table 1]

[0567]

[0568] [Table 2]

[0569]

[0570] Here, PSiCzCz and SiTrzCz2 are organic compounds that are non-deuterated compounds of PSiCzCz-d15 and SiTrzCz2-d16, respectively.

[0571] In addition, a thin film of SiTrzCz2-d16, a thin film of PSiCzCz-d15, and a mixed film co-evaporated with SiTrzCz2-d16 and PSiCzCz-d15 in a weight ratio of 1:1 were respectively evaporated on a quartz substrate with a thickness of 50 nm. Figure 62 The PL spectra of the above-mentioned films are shown. When measuring the PL spectra, a fluorescence spectrophotometer (FP-8600DS manufactured by JASCO Corporation) was used. As Figure 62 shown, the PL spectrum of the mixed film is at a longer wavelength than the PL spectra of the individual films, and thus it can be seen that SiTrzCz2-d16 and PSiCzCz-d15 form an exciplex.

[0572] The phosphorescence lifetimes of PSiCzCz, PSiCzCz-d15, SiTrzCz2, and SiTrzCz2-d16 and the magnification of the change in phosphorescence lifetime due to deuteration are shown below. In addition, the value obtained by multiplying each magnification is 1.40. Note that the excitation wavelength of PSiCzCz and PSiCzCz-d15 was set to 340 nm, and the measurement wavelength was set to 440 nm. The excitation wavelength of SiTrzCz2 and SiTrzCz2-d16 was set to 330 nm, and the measurement wavelength was set to 450 nm.

[0573] [Table 3]

[0574]

[0575] As Figure 2As shown, based on the measurement data, the time when the light quantity is reduced to 50% of that at the start of measurement is set as t = 0, and the time when the light quantity decays to 1 / e of that at t = 0 is denoted as the phosphorescence lifetime. In Figure 2 it, the time when the intensity reaches 50% of the intensity at the start of measurement in the measurement data is set as time 0 s to plot a graph. When the light quantity at 0 s is denoted as 1, the time when this light quantity decays to 1 / e is denoted as the phosphorescence lifetime.

[0576] A PMU-830 type liquid nitrogen cooling device is installed in the FP-8600 manufactured by JASCO Corporation, and measurements are carried out at the liquid nitrogen temperature (77 K).

[0577] The solution of the material is prepared inside the glove box of LABstar M13 (1250 / 780) manufactured by MBRAUN. The sample is dissolved in 2-MeTHF that has undergone freeze degassing treatment to adjust the solution to a concentration of 1.2E -4 M mode. The adjusted solution is placed in a LPH-140 type liquid sample cell (sample tube) for cooling manufactured by JASCO Corporation. The sample tube holder and fixing nuts are installed, and then the lid is covered. After adding liquid nitrogen to the Dewar flask of the cooling device of the FP-8600 to complete the preparation, the sample cell is taken out from the glove box and placed in the Dewar flask with liquid nitrogen in the device for cooling.

[0578] The sample cell is irradiated with excitation light for about 30 seconds, and the luminescence intensity that decays after the excitation light is blocked is measured at intervals of 10 ms, thereby performing time-resolved measurement. As the wavelength for performing phosphorescence lifetime measurement, a wavelength that contains as little fluorescence as possible is selected by comparing the emission spectra in the phosphorescence mode and the fluorescence mode. Note that the excitation wavelength can be appropriately selected, but it is preferably measured at a wavelength of 330 nm. In addition, the bandwidths of the excitation light and the measurement light can be about 10 nm. Since it is ideal for the luminescence to decay in a single exponential function, based on the time when the light quantity is reduced to 50% of that at the start of measurement, the time when the luminescence intensity decays to 1 / e is defined as the phosphorescence luminescence lifetime.

[0579] In addition, the T 1 energy level of PSiCzCz-d15 is 2.97 eV, and the T 1 energy level of SiTrzCz2-d16 is 2.93 eV, and the difference between them is 0.04 eV.

[0580] The emission spectrum (phosphorescence spectrum) is measured at a measurement temperature of 10 K by using a thin film formed by depositing the sample on a quartz substrate with a thickness of 50 nm to calculate T 1Energy level. When performing measurements, a microscopic PL device, LabRAM HR-PL (manufactured by Horiba, Ltd., Japan), was used, and He-Cd laser (325 nm) was used as the excitation light. Additionally, as Figure 61A and Figure 61B shown, a tangent line was drawn at the point with the maximum value of the inclination on the short-wavelength side of the peak (or shoulder peak) observed at the short wavelength of the emission spectrum (phosphorescence spectrum), and the emission end was calculated based on the intersection of this tangent line with the horizontal axis (wavelength) or the baseline.

[0581] Additionally, the 5% weight loss temperature of PSiCzCz-d15 at 10 Pa was 254 °C, and the 5% weight loss temperature of SiTrzCz2-d16 at 10 Pa was 298 °C, with a difference of 45 °C.

[0582] When controlling the pressure to any pressure of 1.0×10 -1 Pa or more and 10 Pa or less by thermogravimetric measurement-differential thermal analysis (TG-DTA: Thermogravimetry-Differential Thermal Analysis), when the weight of the compound used for measurement was 1 mg or more and 20 mg or less, the temperature at which the weight reduced to -5% of the starting weight of the measurement obtained from the thermogravimetric measurement was used as the 5% weight loss temperature. When performing the measurement, a high-vacuum differential type thermogravimetric analyzer (TG-DTA2410SA manufactured by Bruker AXS) was used and the measurement was performed under the conditions of a pressure of 10 Pa, a heating rate of 10 °C / min, and a nitrogen gas flow (flow rate: 30 mL / min). In this example, the sample weight was approximately 3.00 mg (2.95 mg to 3.06 mg).

[0583] Additionally, Figure 63 is a figure showing the overlap of the photoluminescence (PL) spectrum of the exciplex formed by Figure 62 shown PSiCzCz-d15 and SiTrzCz2-d16 with the PL spectrum of the polymer-dispersed film of PtON-TBBI. As Figure 63[[As shown, the PL spectrum of the exciplex formed by PSiCzCz-d15 and SiTrzCz2-d16 overlaps with the PL spectrum of the polymethyl methacrylate (abbreviation: PMMA) dispersion film of PtON-TBBI, and the difference in the wavelength of each maximum peak is 30 nm or less. A solution in which PtON-TBBI is dispersed in PMMA at a concentration of 1.0 wt% using deoxychloromethane as a solvent is deposited on a quartz substrate by the drop-casting method, and dried at room temperature for 30 minutes under a nitrogen stream in a glove box, thereby fabricating the PMMA dispersion film of PtON-TBBI. The emission spectrum of the PMMA dispersion film of PtON-TBBI obtained by measurement using an absolute PL quantum yield measurement device (Quantaurus-QY C11347-01 manufactured by Hamamatsu Photonics K.K. of Japan).

[0584] ​ Shows the luminance-current density characteristics of the light-emitting device 1 and the comparative light-emitting devices 1-1 to 1-3, ​ Shows the current efficiency-current density characteristics, ​ Shows the luminance-voltage characteristics, Figure 25 Shows the current density-voltage characteristics, Figure 26 Shows the external quantum efficiency-luminance characteristics, Figure 27 Shows the blue index (BI)-current density characteristics, Figure 28 Shows the electroluminescence spectrum.

[0585] In addition, the following shows the voltage, current, current density, CIE chromaticity, current efficiency, external quantum efficiency, and blue index (BI) values near 1000 cd / cm 2 Furthermore, the luminance, CIE chromaticity, and electroluminescence spectrum are measured at room temperature using a spectroradiance meter (SR-UL1R manufactured by Topcon Corporation).

[0586] Note that the blue index (BI) is a value obtained by dividing the current efficiency (cd / A) by the y chromaticity calculated using the CIE1931 color system, and is one of the indices representing the light-emitting characteristics of blue light emission. The smaller the y chromaticity of blue light emission, the higher the color purity of the light emission. By using blue light emission with a small y chromaticity and high color purity, blue with a wide chromaticity range can be presented in the display, thereby reducing the luminance of blue light required when the display shows white, and thus having the effect of reducing the power consumption of the display. Therefore, sometimes, the BI of the current efficiency with respect to the y chromaticity, which is one of the indices of blue purity, is used as a means of representing the efficiency of blue light emission, and thus it can be said that the higher the BI, the higher the efficiency of the blue light-emitting device in the display.

[0587] [Table 4]

[0588]

[0589] From Figures 22 to 28 Table 4, it can be seen that the light-emitting device 1 and the comparative light-emitting devices 1-1 to 1-3 are light-emitting devices that are driven with equal luminous efficiency and voltage and exhibit good initial characteristics. In addition, it can also be seen that the peak wavelength of the electroluminescence spectra of the light-emitting device 1 and the comparative light-emitting devices 1-1 to 1-3 is 464 nm, showing blue light emission derived from PtON-TBBI.

[0590] On the other hand, Figure 29 shows the characteristics of the normalized luminance of the light-emitting device 1 and the comparative light-emitting devices 1-1 to 1-3 changing with time when the current density is 10 mA / cm 2 .

[0591] From Figure 29 it can be seen that compared with the comparative light-emitting devices 1-1 to 1-3, the change in the normalized luminance of the light-emitting device 1 of one embodiment of the present invention with time is small, so the light-emitting device 1 is a highly reliable light-emitting device.

[0592] Example 2

[0593] In this embodiment, the manufacturing methods and characteristics of the light-emitting device 2 of one embodiment of the present invention and the comparative light-emitting devices 2-1 to 2-3 of the light-emitting devices for comparison are described in detail. The structural formulas of the main compounds used for the light-emitting device 2 and the comparative light-emitting devices 2-1 to 2-3 are shown below.

[0594] [Chemical formula 5]

[0595]

[0596] (Manufacturing method of the light-emitting device 2)

[0597] First, indium tin oxide (ITSO) containing silicon oxide is laminated on a glass substrate by sputtering to a thickness of 70 nm, thereby forming a first electrode 101 with a size of 2 mm × 2 mm. In addition, the first electrode 101 is used as an anode.

[0598] Next, as a pretreatment for forming a light-emitting device on the substrate, the surface of the substrate is washed with water.

[0599] Then, the substrate is placed in a vacuum evaporation apparatus whose internal pressure is reduced to about 1 × 10 -4 Pa, and in the heating chamber in the vacuum evaporation apparatus, vacuum baking is performed at a temperature of 170 °C for 30 minutes, and then the substrate is cooled for about 30 minutes.

[0600] Next, the substrate is fixed to a holder in a vacuum evaporation apparatus such that the surface on which the first electrode 101 is formed faces downward, and N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf): an electron acceptor material (OCHD-003) containing fluorine with a molecular weight of 672 are co-evaporated on the inorganic insulating film and the first electrode 101 by evaporation method in a weight ratio of 1:0.1 and a thickness of 10 nm to form a hole injection layer 111.

[0601] On the hole injection layer 111, BBABnf is evaporated to a thickness of 30 nm to form a first hole transport layer, and then 9-[3-(triphenylsilyl)phenyl]-3,9'-(bi-9H-carbazole-d 15 )(abbreviation: PSiCzCz-d15) represented by the above structural formula (iv) is evaporated to a thickness of 5 nm to form a second hole transport layer, thereby forming a hole transport layer 112. Note that the second hole transport layer also serves as an electron blocking layer.

[0602] Next, on the hole transport layer 112, 9,9'-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole-1,2,3,4,5,6,7,8,1',2',3',4',5',6',7',8'-d 16 (abbreviation: SiTrzCz2-d16): PSiCzCz-d15: (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazol-1-yl-2-ylidene-κC2]phenoxy-κC2}-9-(4-tert-butyl-2-pyridyl-κN)carbazole-2,1-diyl-κC1)platinum(II) (abbreviation: PtON-TBBI) represented by the above structural formula (v) are co-evaporated in a weight ratio of 0.435:0.435:0.13 and a thickness of 35 nm to form a light-emitting layer 113.

[0603] Then, 2-phenyl-4,6-bis[3-(triphenylsilyl)phenyl]-1,3,5-triazine (abbreviation: mSiTrz) represented by the above structural formula (vi) is evaporated to a thickness of 5 nm to form a first electron transport layer, and then mSiTrz and lithium 8-hydroxyquinolate (abbreviation: Liq) represented by the above structural formula (vii) are co-evaporated in a weight ratio of 1:1 and a thickness of 20 nm to form a second electron transport layer, thereby forming an electron transport layer 114.

[0604] Next, lithium fluoride (LiF) is vapor-deposited to a thickness of 1 nm to form an electron injection layer 115, and then aluminum (Al) is vapor-deposited to a thickness of 200 nm, thereby forming a second electrode 102.

[0605] Next, in a glove box under a nitrogen atmosphere, a sealing process is performed using a glass substrate in such a manner that the light-emitting device is not exposed to the atmosphere (a process of applying a UV-curable sealing material around the element, irradiating only the sealing material with UV without irradiating the light-emitting device with UV, and performing a heat treatment at 80 °C for 1 hour at atmospheric pressure), thereby forming a light-emitting device 2.

[0606] (Manufacturing method of comparative light-emitting device 2-1)

[0607] In comparative light-emitting device 2-1, 9,9’-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole) (abbreviation: SiTrzCz2) shown by the above structural formula (viii) is used instead of SiTrzCz2-d16 in light-emitting device 2, and 9-[3-(triphenylsilyl)phenyl]-3,9’-bi-9H-carbazole (abbreviation: PSiCzCz) shown by the above structural formula (ii) is used instead of PSiCzCz-d15, and it is manufactured in the same manner as light-emitting device 2 except for this.

[0608] (Manufacturing method of comparative light-emitting device 2-2)

[0609] In comparative light-emitting device 2-2, PSiCzCz is used instead of PSiCzCz-d15 in light-emitting device 2, and it is manufactured in the same manner as light-emitting device 2 except for this.

[0610] (Manufacturing method of comparative light-emitting device 2-3)

[0611] In comparative light-emitting device 2-3, SiTrzCz2 is used instead of SiTrzCz2-d16 in light-emitting device 2, and it is manufactured in the same manner as light-emitting device 2 except for this.

[0612] The device structures of light-emitting device 2 and comparative light-emitting devices 2-1 to 2-3 are shown below.

[0613] [Table 5]

[0614]

[0615] [Table 6]

[0616]

[0617] Here, PSiCzCz and SiTrzCz2 are organic compounds of non-deuterated PSiCzCz-d15 and SiTrzCz2-d16, respectively.

[0618] In addition, a thin film of SiTrzCz2-d16, a thin film of PSiCzCz-d15, and a mixed film co-evaporated with SiTrzCz2-d16 and PSiCzCz-d15 in a weight ratio of 1:1 were respectively evaporated on a quartz substrate with a thickness of 50 nm, and Figure 62 the PL spectra of the above films were shown. When measuring the PL spectra, a fluorescence spectrophotometer (FP-8600DS manufactured by JASCO Corporation) was used. As Figure 62 shown, the PL spectrum of the mixed film is at a longer wavelength than the PL spectra of the individual films, so it can be known that SiTrzCz2-d16 and PSiCzCz-d15 form an exciplex.

[0619] The following shows the phosphorescence lifetimes of PSiCzCz, PSiCzCz-d15, SiTrzCz2, and SiTrzCz2-d16 and the magnification of the change in phosphorescence lifetime due to deuteration. In addition, the value obtained by multiplying the respective magnifications is 1.40. Note that the excitation wavelength of PSiCzCz and PSiCzCz-d15 was set to 340 nm, and the measurement wavelength was set to 440 nm. The excitation wavelength of SiTrzCz2 and SiTrzCz2-d16 was set to 330 nm, and the measurement wavelength was set to 450 nm.

[0620] [Table 7]

[0621]

[0622] In addition, the T 1 energy level of PSiCzCz-d15 is 2.97 eV, and the T 1 energy level of SiTrzCz2-d16 is 2.93 eV, and the difference is 0.04 eV.

[0623] In addition, the 5% weight loss temperature of PSiCzCz-d15 at 10 Pa is 254 °C, and the 5% weight loss temperature of SiTrzCz2-d16 at 10 Pa is 298 °C, and the difference is 45 °C.

[0624] In addition, the phosphorescence lifetime, T 1 energy level, and 5% weight loss temperature were calculated in the same manner as in Example 1.

[0625] In addition, Figure 63 is to make by Figure 62The figure showing the overlap of the photoluminescence (PL) spectra of the exciplex formed by PSiCzCz-d15 and SiTrzCz2-d16 with the PL spectrum of the polymer-dispersed film of PtON-TBBI. As Figure 63 shown, the PL spectrum of the exciplex formed by PSiCzCz-d15 and SiTrzCz2-d16 overlaps with the PL spectrum of the polymethyl methacrylate (abbreviation: PMMA)-dispersed film of PtON-TBBI, and the difference in the wavelengths of the respective maximum peaks is 30 nm or less. The PMMA-dispersed film of PtON-TBBI was fabricated in the same manner as in Example 1.

[0626] Figure 30 Showing the luminance-current density characteristics of Light-emitting device 2 and Comparative light-emitting devices 2-1 to 2-3, Figure 31 Showing the current efficiency-current density characteristics, Figure 32 Showing the luminance-voltage characteristics, Figure 33 Showing the current density-voltage characteristics, Figure 34 Showing the external quantum efficiency-luminance characteristics, Figure 35 Showing the blue index (BI)-current density characteristics, Figure 36 Showing the electroluminescent spectrum.

[0627] In addition, the following shows the values of voltage, current, current density, CIE chromaticity, current efficiency, external quantum efficiency, and blue index (BI) near 1000 cd / cm 2 . In addition, the luminance, CIE chromaticity, and electroluminescent spectrum were measured at room temperature using a spectroradiance meter (SR-UL1R manufactured by Topcon Corporation).

[0628] [Table 8]

[0629]

[0630] From Figures 30 to 36 and Table 8, it can be seen that Light-emitting device 2 and Comparative light-emitting devices 2-1 to 2-3 are all light-emitting devices that are driven with equal luminous efficiency and voltage and exhibit good initial characteristics. In addition, it can also be seen that the peak wavelength of the electroluminescent spectrum of Light-emitting device 2 and Comparative light-emitting devices 2-1 to 2-3 is 464 nm, showing blue luminescence derived from PtON-TBBI.

[0631] On the other hand, Figure 37 Showing the normalized luminance change characteristics over time when the current density of Light-emitting device 2 and Comparative light-emitting devices 2-1 to 2-3 is 10 mA / cm 2 .

[0632] From Figure 37It can be seen that, compared with the comparative light-emitting devices 2-1 to 2-3, the normalized brightness of the light-emitting device 2 of one embodiment of the present invention changes little over time. Therefore, the light-emitting device 2 is a highly reliable light-emitting device.

[0633] Example 3

[0634] In this embodiment, the manufacturing methods and characteristics of the light-emitting device 3 of one embodiment of the present invention and the comparative light-emitting devices 3-1 to 3-3 of the comparative light-emitting devices are described in detail. The structural formulas of the main compounds used for the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3 are shown below.

[0635] [Chemical formula 6]

[0636]

[0637] (Manufacturing method of the light-emitting device 3)

[0638] First, indium tin oxide (ITSO) containing silicon oxide is laminated on a glass substrate by sputtering to a thickness of 70 nm, thereby forming a first electrode 101 with a size of 2 mm × 2 mm. In addition, the first electrode 101 is used as an anode.

[0639] Next, as a pretreatment for forming a light-emitting device on the substrate, the surface of the substrate is washed with water.

[0640] Then, the substrate is placed in a vacuum evaporation apparatus whose internal pressure is reduced to about 1 × 10 -4 Pa, and in the heating chamber in the vacuum evaporation apparatus, vacuum baking is performed at a temperature of 170 °C for 30 minutes, and then the substrate is cooled for about 30 minutes.

[0641] Next, the substrate is fixed on a bracket in the vacuum evaporation apparatus with the surface on which the first electrode 101 is formed facing downward, and N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluorene-2-amine (abbreviation: PCBBiF) shown in the above structural formula (ix): an electron acceptor material (OCHD-003) containing fluorine with a molecular weight of 672 are co-evaporated in a weight ratio of 1:0.03 and to a thickness of 10 nm on the inorganic insulating film and the first electrode 101 to form a hole injection layer 111.

[0642] On the hole injection layer 111, PCBBiF is vapor-deposited to form a first hole transport layer with a thickness of 30 nm. Then, 9-[3-(triphenylsilyl)phenyl]-3,9'-bi-9H-carbazole (abbreviation: PSiCzCz) shown in the above structural formula (ii) is vapor-deposited with a thickness of 5 nm to form a second hole transport layer, thereby forming the hole transport layer 112. In addition, the second hole transport layer also serves as an electron blocking layer.

[0643] Next, on the hole transport layer 112, 9,9'-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole-1,2,3,4,5,6,7,8,1',2',3',4',5',6',7',8'-d 16 )(abbreviation: SiTrzCz2-d16): 9-[3-(triphenylsilyl)phenyl]-3,9'-(bi-9H-carbazole-d 15 )(abbreviation: PSiCzCz-d15): (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazol-1-yl-2-ylidene-κC2]phenoxy-κC2}-9-[5-(methyl-d3)-4-phenyl-2-pyridyl-κN]carbazole-2,1-diyl-κC)platinum(II) (abbreviation: Pt(mmtBubOcz5m4ppy-d 3 )) are co-vapor-deposited in a weight ratio of 0.45:0.45:0.10 and with a thickness of 35 nm to form the light-emitting layer 113. 3 ))

[0644] Then, 2-phenyl-4,6-bis[3-(triphenylsilyl)phenyl]-1,3,5-triazine (abbreviation: mSiTrz) shown in the above structural formula (vi) is vapor-deposited with a thickness of 5 nm to form a first electron transport layer. Then, 2,2'-(1,3-phenylene)bis(9-phenyl-1,10-phenanthroline) (abbreviation: mPPhen2P) shown in the above structural formula (xi) is vapor-deposited with a thickness of 20 nm to form a second electron transport layer, thereby forming the electron transport layer 114.

[0645] Next, lithium fluoride (LiF) is vapor-deposited with a thickness of 1 nm to form an electron injection layer 115. Then, aluminum (Al) is vapor-deposited with a thickness of 200 nm, thereby forming the second electrode 102.

[0646] Next, in a glove box filled with nitrogen gas, a sealing process was performed using a glass substrate in such a way that the light-emitting device was not exposed to the atmosphere (applying a UV-curable sealing material around the components, treating only the sealing material with UV without irradiating the light-emitting device with UV, and performing a heat treatment at 80 °C for 1 hour at atmospheric pressure), thereby forming the light-emitting device 3.

[0647] (Manufacturing method of comparative light-emitting device 3-1)

[0648] In the comparative light-emitting device 3-1, 9,9'-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole) (abbreviation: SiTrzCz2) shown by the above structural formula (viii) was used instead of SiTrzCz2-d16 in the light-emitting device 3, and PSiCzCz was used instead of PSiCzCz-d15, and it was manufactured in the same manner as the light-emitting device 3 except for this.

[0649] (Manufacturing method of comparative light-emitting device 3-2)

[0650] In the comparative light-emitting device 3-2, PSiCzCz was used instead of PSiCzCz-d15 in the light-emitting device 3, and it was manufactured in the same manner as the light-emitting device 3 except for this.

[0651] (Manufacturing method of comparative light-emitting device 3-3)

[0652] In the comparative light-emitting device 3-3, SiTrzCz2 was used instead of SiTrzCz2-d16 in the light-emitting device 3, and it was manufactured in the same manner as the light-emitting device 3 except for this.

[0653] The device structures of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3 are shown below.

[0654] [Table 9]

[0655]

[0656] [Table 10]

[0657]

[0658] Here, PSiCzCz and SiTrzCz2 are organic compounds that are non-deuterated compounds of PSiCzCz-d15 and SiTrzCz2-d16, respectively.

[0659] In addition, a thin film of SiTrzCz2-d16, a thin film of PSiCzCz-d15, and a mixed film co-evaporated with SiTrzCz2-d16 and PSiCzCz-d15 in a weight ratio of 1:1 were respectively evaporated on a quartz substrate to a thickness of 50 nm, andFigure 62 The PL spectra of the above-mentioned films are shown. When measuring the PL spectra, a fluorescence spectrophotometer (FP-8600DS manufactured by JASCO Corporation) was used. As Figure 62 shown, the PL spectra of the mixed films are at longer wavelengths than those of the individual films. Therefore, it is known that SiTrzCz2-d16 and PSiCzCz-d15 form an exciplex.

[0660] The following shows the magnification of the change in the phosphorescence lifetime due to deuteration for the phosphorescence lifetimes of PSiCzCz, PSiCzCz-d15, SiTrzCz2, and SiTrzCz2-d16. In addition, the value obtained by multiplying each magnification is 1.40. Note that the excitation wavelength of PSiCzCz and PSiCzCz-d15 was set to 340 nm, and the measurement wavelength was set to 440 nm. The excitation wavelength of SiTrzCz2 and SiTrzCz2-d16 was set to 330 nm, and the measurement wavelength was set to 450 nm.

[0661] [Table 11]

[0662]

[0663] In addition, the T 1 energy level of PSiCzCz-d15 is 2.97 eV, and the T 1 energy level of SiTrzCz2-d16 is 2.93 eV, and the difference is 0.04 eV.

[0664] In addition, the 5% weight loss temperature of PSiCzCz-d15 at 10 Pa is 254 °C, and the 5% weight loss temperature of SiTrzCz2-d16 at 10 Pa is 298 °C, and the difference is 45 °C.

[0665] Note that the phosphorescence lifetime, T 1 energy level, and 5% weight loss temperature were calculated in the same manner as in Example 1.

[0666] In addition, Figure 64 is a graph in which the photoluminescence (PL) spectrum of the exciplex formed by PSiCzCz-d15 and SiTrzCz2-d16 shown by Figure 62 is overlapped with the PL spectrum of a poly(methyl methacrylate) (abbreviation: PMMA) dispersion film of Pt(mmtBubOcz5m4ppy-d 3 ). As Figure 64 shown, the PL spectrum of the exciplex formed by PSiCzCz-d15 and SiTrzCz2-d16 overlaps with the PL spectrum of Pt(mmtBubOcz5m4ppy-d 3) The PL spectra of the PMMA dispersion films overlap, and the difference in the wavelengths of the maximum peaks is 30 nm or less. Using the drop-casting method, a solution in which Pt(mmtBubOcz5m4ppy-d 3 ) is dispersed in PMMA at a concentration of 4.7 wt% is deposited on a quartz substrate, and dried at room temperature for 30 minutes under a nitrogen stream in a glove box, thereby fabricating a PMMA dispersion film of Pt(mmtBubOcz5m4ppy-d 3 ) The emission spectrum of the obtained PMMA dispersion film of Pt(mmtBubOcz5m4ppy-d 3 ) is measured using an absolute PL quantum yield measurement device (Quantaurus-QY C11347-01 manufactured by Hamamatsu Photonics K.K., Japan).

[0667] Figure 38 Shows the luminance-current density characteristics of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3, Figure 39 Shows the current efficiency-current density characteristics, Figure 40 Shows the luminance-voltage characteristics, Figure 41 Shows the current density-voltage characteristics, Figure 42 Shows the external quantum efficiency-luminance characteristics, Figure 43 Shows the blue index (BI)-current density characteristics, Figure 44 Shows the electroluminescence spectrum.

[0668] In addition, the following shows the values of voltage, current, current density, CIE chromaticity, current efficiency, external quantum efficiency, and blue index (BI) near 1000 cd / cm 2 Furthermore, the luminance, CIE chromaticity, and electroluminescence spectrum are measured at room temperature using a spectroradiometer (SR-UL1R manufactured by Topcon Corporation).

[0669] [Table 12]

[0670]

[0671] From Figures 38 to 44 and Table 12, it can be seen that: the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3 are all light-emitting devices that are driven with equal luminous efficiency and voltage and exhibit good initial characteristics. In addition, it can also be seen that: the peak wavelength of the electroluminescence spectrum of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3 is 477 nm, showing blue luminescence derived from Pt(mmtBubOcz5m4ppy-d 3 ).

[0672] On the other hand, Figure 45The current density of the light-emitting device 3 and the comparative light-emitting devices 3-1 to 3-3 is shown as 10 mA / cm 2 The characteristics of the normalized luminance changing with time are shown.

[0673] From Figure 45 It can be seen that: compared with the comparative light-emitting devices 3-1 to 3-3, the normalized luminance of the light-emitting device 3 of one embodiment of the present invention changes less with time. Therefore, the light-emitting device 3 is a highly reliable light-emitting device.

[0674] Example 4

[0675] In this embodiment, the manufacturing methods and characteristics of the light-emitting device 4 of one embodiment of the present invention and the comparative light-emitting devices 4-1 to 4-3 of the comparative light-emitting devices are described in detail. The structural formulas of the main compounds used for the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3 are shown below.

[0676] [Chemical formula 7]

[0677]

[0678] (Manufacturing method of the light-emitting device 4)

[0679] First, indium tin oxide (ITSO) containing silicon oxide is laminated on a glass substrate by sputtering to a thickness of 70 nm, thereby forming a first electrode 101 with a size of 2 mm × 2 mm. In addition, the first electrode 101 is used as an anode.

[0680] Next, as a pretreatment for forming a light-emitting device on the substrate, the surface of the substrate is washed with water.

[0681] Then, the substrate is placed in a vacuum evaporation apparatus whose internal pressure is reduced to about 1 × 10 -4 Pa, and in the heating chamber in the vacuum evaporation apparatus, vacuum baking is performed at a temperature of 170 °C for 30 minutes, and then the substrate is cooled for about 30 minutes.

[0682] Next, the substrate is fixed on a bracket in the vacuum evaporation apparatus with the surface on which the first electrode 101 is formed facing downward, and N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluorene-2-amine (abbreviation: PCBBiF) shown in the above structural formula (ix): an electron acceptor material (OCHD-003) containing fluorine with a molecular weight of 672 are co-evaporated in a weight ratio of 1:0.03 and a thickness of 10 nm on the inorganic insulating film and the first electrode 101 to form a hole injection layer 111.

[0683] On the hole injection layer 111, PCBBiF is vapor-deposited to form the first hole transport layer with a thickness of 30 nm. Then, 9-[3-(triphenylsilyl)phenyl]-3,9'-(bi-9H-carbazole-d 15 )(abbreviation: PSiCzCz-d15) shown in the above structural formula (iv) is vapor-deposited with a thickness of 5 nm to form the second hole transport layer, thereby forming the hole transport layer 112. In addition, the second hole transport layer is also used as an electron blocking layer.

[0684] Next, on the hole transport layer 112, 9,9'-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole-1,2,3,4,5,6,7,8,1',2',3',4',5',6',7',8'-d 16 )(abbreviation: SiTrzCz2-d16): PSiCzCz-d15: (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazol-1-yl-2-ylidene-κC2]phenoxy-κC2}-9-[5-(methyl-d3)-4-phenyl-2-pyridyl-κN]carbazole-2,1-diyl-κC)platinum(II) (abbreviation: Pt(mmtBubOcz5m4ppy-d 3 )) shown in the above structural formula (x) are co-vapor-deposited in a weight ratio of 0.45:0.45:0.10 and with a thickness of 35 nm to form the light-emitting layer 113. 3 )

[0685] Then, 2-phenyl-4,6-bis[3-(triphenylsilyl)phenyl]-1,3,5-triazine (abbreviation: mSiTrz) shown in the above structural formula (vi) is vapor-deposited with a thickness of 5 nm to form the first electron transport layer. Then, 2,2'-(1,3-phenylene)bis(9-phenyl-1,10-phenanthroline) (abbreviation: mPPhen2P) shown in the above structural formula (xi) is vapor-deposited with a thickness of 20 nm to form the second electron transport layer, thereby forming the electron transport layer 114.

[0686] Next, lithium fluoride (LiF) is vapor-deposited with a thickness of 1 nm to form the electron injection layer 115. Then, aluminum (Al) is vapor-deposited with a thickness of 200 nm, thereby forming the second electrode 102.

[0687] Next, in a glove box filled with nitrogen gas, a sealing process was performed using a glass substrate in such a way that the light-emitting device was not exposed to the atmosphere (applying a UV-curable sealing material around the element, performing a process of irradiating only the sealing material with UV without irradiating the light-emitting device with UV, and performing a heat treatment at 80 °C for 1 hour under atmospheric pressure), thereby forming the light-emitting device 4.

[0688] (Manufacturing method of comparative light-emitting device 4-1)

[0689] In the comparative light-emitting device 4-1, 9,9'-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole) (abbreviation: SiTrzCz2) shown by the above structural formula (viii) was used instead of SiTrzCz2-d16 in the light-emitting device 4, and 9-[3-(triphenylsilyl)phenyl]-3,9'-bi-9H-carbazole (abbreviation: PSiCzCz) shown by the above structural formula (ii) was used instead of PSiCzCz-d15, and it was manufactured in the same manner as the light-emitting device 4 except for this.

[0690] (Manufacturing method of comparative light-emitting device 4-2)

[0691] In the comparative light-emitting device 4-2, PSiCzCz was used instead of PSiCzCz-d15 in the light-emitting device 4, and it was manufactured in the same manner as the light-emitting device 4 except for this.

[0692] (Manufacturing method of comparative light-emitting device 4-3)

[0693] In the comparative light-emitting device 4-3, SiTrzCz2 was used instead of SiTrzCz2-d16 in the light-emitting device 4, and it was manufactured in the same manner as the light-emitting device 4 except for this.

[0694] The device structures of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3 are shown below.

[0695] [Table 13]

[0696]

[0697] [Table 14]

[0698]

[0699] Here, PSiCzCz and SiTrzCz2 are organic compounds that are non-deuterated substances of PSiCzCz-d15 and SiTrzCz2-d16, respectively.

[0700] In addition, a film of SiTrzCz2-d16, a film of PSiCzCz-d15, and a mixed film formed by co-evaporating SiTrzCz2-d16 and PSiCzCz-d15 in a weight ratio of 1:1 were respectively evaporated on a quartz substrate with a thickness of 50 nm, and Figure 62 the PL spectra of the above films were shown. When measuring the PL spectra, a fluorescence spectrophotometer (FP-8600DS manufactured by JASCO Corporation) was used. As Figure 62 shown, the PL spectrum of the mixed film is at a longer wavelength than the PL spectra of the individual films, and thus it can be known that SiTrzCz2-d16 and PSiCzCz-d15 form an exciplex.

[0701] The following shows the phosphorescence lifetimes of PSiCzCz, PSiCzCz-d15, SiTrzCz2, and SiTrzCz2-d16 and the magnification of the change in phosphorescence lifetime due to deuteration. In addition, the value obtained by multiplying the respective magnifications is 1.40. Note that the excitation wavelength of PSiCzCz and PSiCzCz-d15 was set to 340 nm, and the measurement wavelength was set to 440 nm. The excitation wavelength of SiTrzCz2 and SiTrzCz2-d16 was set to 330 nm, and the measurement wavelength was set to 450 nm.

[0702] [Table 15]

[0703]

[0704] In addition, the T 1 energy level of PSiCzCz-d15 is 2.97 eV, and the T 1 energy level of SiTrzCz2-d16 is 2.93 eV, and the difference is 0.04 eV.

[0705] In addition, the 5% weight loss temperature of PSiCzCz-d15 at 10 Pa is 254 °C, and the 5% weight loss temperature of SiTrzCz2-d16 at 10 Pa is 298 °C, and the difference is 45 °C.

[0706] Note that the phosphorescence lifetime, T 1 energy level, and 5% weight loss temperature were calculated in the same manner as in Example 1.

[0707] In addition, Figure 64 is a graph in which the photoluminescence (PL) spectrum of the exciplex formed by PSiCzCz-d15 and SiTrzCz2-d16 shown by Figure 62 is overlapped with the PL spectrum of a polymethyl methacrylate (abbreviation: PMMA) dispersion film of Pt(mmtBubOcz5m4ppy-d 3 ). As Figure 64As shown, the PL spectrum of the exciplex formed by PSiCzCz-d15 and SiTrzCz2-d16 overlaps with the PL spectrum of the PMMA dispersion film of Pt(mmtBubOcz5m4ppy-d 3 ), and the difference in the wavelengths of the respective maximum peaks is 30 nm or less. Using the drop-casting method, a solution in which Pt(mmtBubOcz5m4ppy-d 3 ) is dispersed in PMMA at a concentration of 4.7 wt% using deoxychloromethane as a solvent is deposited on a quartz substrate, and drying is performed at room temperature for 30 minutes under a nitrogen flow in a glove box, thereby producing a PMMA dispersion film of Pt(mmtBubOcz5m4ppy-d 3 ). The emission spectrum of the obtained PMMA dispersion film of Pt(mmtBubOcz5m4ppy-d 3 ) is measured by using an absolute PL quantum yield measurement device (Quantaurus-QY C11347-01 manufactured by Hamamatsu Photonics K.K. of Japan).

[0708] Figure 46 Shows the luminance-current density characteristics of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3, Figure 47 shows the current efficiency-current density characteristics, Figure 48 shows the luminance-voltage characteristics, Figure 49 shows the current density-voltage characteristics, Figure 50 shows the external quantum efficiency-luminance characteristics, Figure 51 shows the blue index (BI)-current density characteristics, Figure 52 shows the electroluminescence spectrum.

[0709] In addition, the following shows the values of voltage, current, current density, CIE chromaticity, current efficiency, external quantum efficiency, and blue index (BI) around 1000 cd / cm 2 . In addition, the luminance, CIE chromaticity, and electroluminescence spectrum are measured at room temperature using a spectroradiometer (SR-UL1R manufactured by Topcon Corporation).

[0710] [Table 16]

[0711]

[0712] From Figures 46 to 52As can be seen from Table 16, the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3 are light-emitting devices that are driven with equal luminous efficiency and voltage and exhibit good initial characteristics. In addition, the peak wavelength of the electroluminescence spectra of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3 is 477 nm, showing blue luminescence derived from Pt(mmtBubOcz5m4ppy-d 3 ).

[0713] On the other hand, Figure 53 shows the characteristics of the normalized luminance of the light-emitting device 4 and the comparative light-emitting devices 4-1 to 4-3 changing with time when the current density is 10 mA / cm 2 .

[0714] From Figure 53 , it can be seen that compared with the comparative light-emitting devices 4-1 to 4-3, the normalized luminance of the light-emitting device 4 of one embodiment of the present invention changes less with time. Therefore, the light-emitting device 4 is a highly reliable light-emitting device.

[0715] Example 5

[0716] In this embodiment, the manufacturing methods and characteristics of the light-emitting device 5 of one embodiment of the present invention and the comparative light-emitting devices 5-1 to 5-3 of the light-emitting devices used for comparison are described in detail. The structural formulas of the main compounds used for the light-emitting device 5 and the comparative light-emitting devices 5-1 to 5-3 are shown below.

[0717] [Chemical formula 8]

[0718]

[0719] (Manufacturing method of the light-emitting device 5)

[0720] First, silver (Ag) with a thickness of 100 nm and indium tin oxide (ITSO) containing silicon oxide with a thickness of 10 nm are sequentially laminated on a glass substrate by sputtering to form a first electrode 101 with a size of 2 mm × 2 mm. In addition, the first electrode 101 is used as an anode.

[0721] Next, as a pretreatment for forming a light-emitting device on the substrate, the surface of the substrate is washed with water.

[0722] Then, the substrate is placed in a vacuum evaporation apparatus whose internal pressure is reduced to about 1 × 10 -4 Pa, and in the heating chamber of the vacuum evaporation apparatus, vacuum baking is performed at a temperature of 170 °C for 30 minutes, and then the substrate is cooled for about 30 minutes.

[0723] Next, the substrate is fixed to a holder in a vacuum evaporation apparatus such that the surface on which the first electrode 101 is formed faces downward, and on the inorganic insulating film and the first electrode 101, N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluorene-2-amine (abbreviation: PCBBiF) shown by the above structural formula (ix) and an electron acceptor material (OCHD-003) containing fluorine with a molecular weight of 672 are co-evaporated at a weight ratio of 1:0.03 and a thickness of 10 nm to form a hole injection layer 111.

[0724] On the hole injection layer 111, PCBBiF is evaporated to a thickness of 140 nm to form a hole transport layer 112.

[0725] Next, on the hole transport layer 112, 8-(1,1':4',1''-terphenyl-3-yl-2,4,5,6,2',3',5',6',2'',3'',4'',5'',6''-d13)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8mpTP-4mDBtPBfpm-d13) shown by the above structural formula (xii), 9-(2-naphthyl-1,3,4,5,6,7,8-d7)-9'-(phenyl-2,3,4,5,6-d5)-9H,9'H-3,3'-bicarbazole-1,1',2,2',4,4',5,5',6,6',7,7',8,8'-d14 (abbreviation: βNCCP-d26) shown by the above structural formula (xiii), and tris{2-[5-(methyl-d3)-4-phenyl-2-pyridyl-κN]phenyl-κC}iridium(III) (abbreviation: Ir(5m4dppy-d 3 ) 3 ) are co-evaporated at a weight ratio of 0.4:0.6:0.1 and a thickness of 40 nm to form a light-emitting layer 113. 3 ) 3 )

[0726] Then, 2-{3-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}dibenzof[f,h]quinoxaline (abbreviation: 2mPCCzPDBq) shown by the above structural formula (xv) was vapor-deposited in a thickness of 10 nm to form a first electron transport layer, and then 2,2'-(1,3-phenylene)bis(9-phenyl-1,10-phenanthroline) (abbreviation: mPPhen2P) shown by the above structural formula (xi) was vapor-deposited in a thickness of 20 nm to form a second electron transport layer, thereby forming the electron transport layer 114.

[0727] Next, lithium fluoride (LiF) was vapor-deposited in a thickness of 1 nm to form an electron injection layer 115, and then co-vapor deposition was performed with a volume ratio of silver (Ag) to magnesium (Mg) of 1:0.1 and a thickness of 15 nm to form a second electrode 102. Finally, on the second electrode 102, 4,4',4''-(benzene-1,3,5-triyl)tris(dibenzothiophene) (abbreviation: DBT3P-II) shown by the above structural formula (xvi) was deposited in a thickness of 70 nm as a capping layer.

[0728] Next, in a glove box under a nitrogen atmosphere, a sealing treatment was performed using a glass substrate in such a way that the light-emitting device was not exposed to the atmosphere (applying a UV-curable sealing material around the element, performing a treatment of irradiating only the sealing material with UV without irradiating the light-emitting device with UV, and performing a heat treatment at 80 °C for 1 hour under atmospheric pressure), thereby forming the light-emitting device 5.

[0729] (Manufacturing method of comparative light-emitting device 5-1)

[0730] In the comparative light-emitting device 5-1, 8-(p-terphenyl-3-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8mpTP-4mDBtPBfpm) shown by the above structural formula (xvii) was used instead of 8mpTP-4mDBtPBfpm-d13 in the light-emitting device 5, and 9-(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: βNCCP) shown by the above structural formula (xviii) was used instead of βNCCP-d26, and it was manufactured in the same manner as the light-emitting device 5 except for this.

[0731] (Manufacturing method of comparative light-emitting device 5-2)

[0732] In the comparative light-emitting device 5-2, βNCCP was used instead of βNCCP-d26 in the light-emitting device 5, and it was manufactured in the same manner as the light-emitting device 5 except for this.

[0733] (Manufacturing method of comparative light-emitting device 5-3)

[0734] In the comparative light-emitting device 5-3, 8mpTP-4mDBtPBfpm was used instead of 8mpTP-4mDBtPBfpm-d13 in the light-emitting device 5, and it was manufactured in the same manner as the light-emitting device 5 except for this.

[0735] The device structures of the light-emitting device 5 and the comparative light-emitting devices 5-1 to 5-3 are shown below.

[0736] [Table 17]

[0737]

[0738] [Table 18]

[0739]

[0740] Here, 8mpTP-4mDBtPBfpm and βNCCP are organic compounds that are non-deuterated forms of 8mpTP-4mDBtPBfpm-d13 and βNCCP-d26, respectively.

[0741] In addition, a thin film of 8mpTP-4mDBtPBfpm-d13, a thin film of βNCCP-d26, and a mixed film co-evaporated with 8mpTP-4mDBtPBfpm-d13 and βNCCP-d26 in a weight ratio of 1:1 were respectively evaporated on a quartz substrate with a thickness of 50 nm. Figure 65 The PL spectra of the respective films are shown. When measuring the PL spectra, a fluorescence spectrophotometer (FP-8600DS manufactured by JASCO Corporation) was used. As Figure 65 shown, the PL spectrum of the mixed film is at a longer wavelength than the PL spectra of the individual films, and thus it can be seen that 8mpTP-4mDBtPBfpm-d13 and βNCCP-d26 form an exciplex.

[0742] The following shows the phosphorescence lifetimes of βNCCP, βNCCP-d26, 8mpTP-4mDBtPBfpm, and 8mpTP-4mDBtPBfpm-d13 and the magnification of the change in phosphorescence lifetime due to deuteration. In addition, the value obtained by multiplying the respective magnifications is 5.72. Note that the excitation wavelength of βNCCP and βNCCP-d26 was set to 330 nm, and the measurement wavelength was set to 515 nm. The excitation wavelength of 8mpTP-4mDBtPBfpm and 8mpTP-4mDBtPBfpm-d13 was set to 320 nm, and the measurement wavelength was set to 515 nm.

[0743] [Table 19]

[0744]

[0745] In addition, the T 1 energy level of βNCCP-d26 is 2.56 eV, and the T 1 energy level of 8mpTP-4mDBtPBfpm-d13 is 2.55 eV, and the difference therebetween is 0.01 eV.

[0746] In addition, the 5% weight loss temperature of βNCCP-d26 under 10 Pa is 257 °C, and the 5% weight loss temperature of 8mpTP-4mDBtPBfpm-d13 under 10 Pa is 312 °C, and the difference therebetween is 55 °C.

[0747] In addition, the phosphorescence lifetime, T 1 energy level and 5% weight loss temperature were calculated in the same manner as in Example 1.

[0748] In addition, as Figure 66 shown, the PL spectrum of the exciplex formed by βNCCP-d26 and 8mpTP-4mDBtPBfpm-d13 overlaps with the PL spectrum of Ir(5m4dppy-d 3 ) 3 . When measuring the PL spectrum of the dichloromethane solution of Ir(5m4dppy-d 3 ) 3 , a fluorescence spectrophotometer (FP-8600DS manufactured by JASCO Corporation) was used.

[0749] Figure 54 Fig. shows the luminance-current density characteristics of the light-emitting device 5 and the comparative light-emitting devices 5-1 to 5-3, Figure 55 shows the luminance-voltage characteristics, Figure 56 shows the current efficiency-current density characteristics, Figure 57 shows the current density-voltage characteristics, Figure 58 shows the external quantum efficiency-current density characteristics, Figure 59 shows the electroluminescence spectrum.

[0750] In addition, the values of voltage, current, current density, CIE chromaticity, current efficiency, and external quantum efficiency near 1000 cd / cm 2 are shown below. In addition, the luminance, CIE chromaticity, and electroluminescence spectrum were measured at room temperature using a spectroradiance meter (SR-UL1R manufactured by Topcon Corporation).

[0751] [Table 20]

[0752]

[0753] From Figures 54 to 59As can be seen from Table 20, the light-emitting device 5 and the comparative light-emitting devices 5-1 to 5-3 are light-emitting devices that are driven with equal luminous efficiency and voltage and exhibit good initial characteristics.

[0754] On the other hand, Figure 60 shows the characteristics of the normalized luminance over time when the current density of the light-emitting device 5 and the comparative light-emitting devices 5-1 to 5-3 is 50 mA / cm 2 .

[0755] From Figure 60 it can be seen that, compared with the comparative light-emitting devices 5-1 to 5-3, the normalized luminance of the light-emitting device 5 of one embodiment of the present invention changes less over time. Therefore, the light-emitting device 5 is a highly reliable light-emitting device.

[0756] Example 6

[0757] In this embodiment, the manufacturing methods and characteristics of the light-emitting device 6 of one embodiment of the present invention and the comparative light-emitting device 6 of the comparative light-emitting device are described in detail. The following shows the structural formulas of the main compounds used for the light-emitting device 6 and the comparative light-emitting device 6.

[0758] [Chemical formula 9]

[0759]

[0760] (Manufacturing method of the light-emitting device 6)

[0761] First, indium tin oxide (ITSO) containing silicon oxide is laminated on a glass substrate by sputtering to a thickness of 110 nm, thereby forming a first electrode 101 with a size of 2 mm × 2 mm. In addition, the first electrode 101 is used as an anode.

[0762] Next...

Claims

1. A light emitting device, comprising: a first electrode; a second electrode; as well as Luminescent layer, Wherein, the light-emitting layer is located between the first electrode and the second electrode, The light-emitting layer comprises a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light emission. The first organic compound has a π-electron-deficient heteroaromatic ring, The second organic compound has a π-electron-rich heteroaromatic ring or an aromatic amine skeleton, The first organic compound and the second organic compound contain deuterium, Furthermore, a difference between the lowest triplet excitation energy level of the first organic compound and the lowest triplet excitation energy level of the second organic compound is 0.20 eV or less.

2. A light emitting device, comprising: a first electrode; a second electrode; as well as Luminescent layer, Wherein, the light-emitting layer is located between the first electrode and the second electrode, The light-emitting layer comprises a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light emission. The first organic compound has a π-electron-deficient heteroaromatic ring, The second organic compound has a π-electron-rich heteroaromatic ring or an aromatic amine skeleton, The first organic compound and the second organic compound contain deuterium, The combination of the first organic compound and the second organic compound forms an exciplex, Furthermore, the emission spectrum of the exciplex overlaps with the emission spectrum of the substance capable of converting triplet excitation energy into luminescence.

3. The light emitting device according to claim 2, The difference between the maximum peak wavelength of the emission spectrum of the exciplex and the maximum peak wavelength of the emission spectrum of the substance capable of converting triplet excitation energy into luminescence is 30 nm or less.

4. The light emitting device according to claim 1, wherein the phosphorescence lifetime or delayed fluorescence lifetime of the first organic compound at 77K is at least 1.20 times the phosphorescence lifetime or delayed fluorescence lifetime of a third organic compound which is a non-deuterated derivative of the first organic compound at 77K, The phosphorescence lifetime or delayed fluorescence lifetime of the second organic compound at 77K is 1.05 times or more the phosphorescence lifetime or delayed fluorescence lifetime of a fourth organic compound that is not a deuterated derivative of the second organic compound at 77K.

5. The light emitting device according to claim 4, The peak wavelength of the emission spectrum of the substance capable of converting triplet excitation energy into luminescence is 450 nm or more and less than 500 nm.

6. The light emitting device according to claim 1, wherein the phosphorescence lifetime or delayed fluorescence lifetime of the first organic compound at 77K is at least 1.50 times the phosphorescence lifetime or delayed fluorescence lifetime of a third organic compound which is a non-deuterated organic compound of the first organic compound at 77K, The phosphorescence lifetime or delayed fluorescence lifetime of the second organic compound at 77K is 3.00 times or more than the phosphorescence lifetime or delayed fluorescence lifetime of a fourth organic compound which is a non-deuterated organic compound of the second organic compound at 77K.

7. The light emitting device according to claim 6, The peak wavelength of the emission spectrum of the substance capable of converting triplet excitation energy into luminescence is 500 nm to 600 nm.

8. The light emitting device according to claim 1, Wherein, when the phosphorescence lifetime or delayed fluorescence lifetime at 77K of the first organic compound is X times the phosphorescence lifetime or delayed fluorescence lifetime at 77K of a third organic compound which is a non-deuterated form of the first organic compound, and the phosphorescence lifetime or delayed fluorescence lifetime at 77K of the second organic compound is Y times the phosphorescence lifetime or delayed fluorescence lifetime at 77K of a fourth organic compound which is a non-deuterated form of the second organic compound, the value obtained by multiplying X by Y is greater than 1.

26.

9. The light emitting device according to claim 1, wherein the peak wavelength of the emission spectrum of the substance capable of converting triplet excitation energy into luminescence is 500 nm or more and 600 nm or less, And when the phosphorescence lifetime or delayed fluorescence lifetime at 77K of the first organic compound is X times the phosphorescence lifetime or delayed fluorescence lifetime at 77K of a third organic compound which is a non-deuterated form of the first organic compound, and the phosphorescence lifetime or delayed fluorescence lifetime at 77K of the second organic compound is Y times the phosphorescence lifetime or delayed fluorescence lifetime at 77K of a fourth organic compound which is a non-deuterated form of the second organic compound, the value obtained by multiplying X by Y is greater than 4.

50.

10. A light emitting device, comprising: a first electrode; a second electrode; as well as Luminescent layer, Wherein, the light-emitting layer is located between the first electrode and the second electrode, The light-emitting layer comprises a first organic compound, a second organic compound, and a substance capable of converting triplet excitation energy into light emission. The first organic compound has a π-electron-deficient heteroaromatic ring, The second organic compound has a π-electron-rich heteroaromatic ring or an aromatic amine skeleton, The first organic compound and the second organic compound contain deuterium, Furthermore, a difference between a 5% weight loss temperature at 10 Pa of the first organic compound and a 5% weight loss temperature at 10 Pa of the second organic compound is 60° C. or less.

11. The light emitting device according to claim 1, The substance capable of converting triplet excitation energy into luminescence is a phosphorescent substance.

12. The light emitting device according to claim 1, The combination of the first organic compound and the second organic compound forms an exciplex.

13. The light emitting device according to claim 1, wherein the first organic compound has a diazine skeleton or a triazine skeleton, And the second organic compound has a bicarbazole skeleton.

14. The light emitting device according to claim 2, The substance capable of converting triplet excitation energy into luminescence is a phosphorescent substance.

15. The light emitting device according to claim 2, wherein the first organic compound has a diazine skeleton or a triazine skeleton, And the second organic compound has a bicarbazole skeleton.

16. The light emitting device according to claim 10, The substance capable of converting triplet excitation energy into luminescence is a phosphorescent substance.

17. The light emitting device according to claim 10, The combination of the first organic compound and the second organic compound forms an exciplex.

18. The light emitting device according to claim 10, wherein the first organic compound has a diazine skeleton or a triazine skeleton, And the second organic compound has a bicarbazole skeleton.

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