Organic compound

Abstract

To provide a novel organic compound and a light-emitting device using the organic compound. One embodiment of the present invention is an organic compound represented by general formula (G1). In the formula, A represents a substituted or unsubstituted spirobifluorenyl group; and R1 to R5 represent hydrogen (including deuterium), a C3-7 chain alkyl group, or a C3-10 cyclic alkyl group, provided that at least one of R1 to R5 represents a C3-7 chain alkyl group or a C3-10 cyclic alkyl group.

Description

organic compound

[0001] One aspect of the present invention relates to organic compounds, organic semiconductor elements, light-emitting devices, photodiode sensors, display modules, lighting modules, display devices, electronic devices, lighting devices, and electronic devices. However, one aspect of the present invention is not limited to the above-mentioned technical fields. One aspect of the present invention disclosed herein relates to a product, a method, or a method of manufacture. Alternatively, one aspect of the present invention relates to a process, a machine, a manufacture, or a composition of matter. More specifically, one example of a technical field of one aspect of the present invention disclosed herein is a semiconductor device, a display device, a liquid crystal display device, a lighting device, a power storage device, a memory device, an imaging device, a method for driving them, or a method for manufacturing them.

[0002] Light-emitting devices (also known as organic electroluminescent elements) that have an organic compound, which is a light-emitting material, between a pair of electrodes have characteristics such as being thin, lightweight, fast response, and low voltage drive, and development of displays that utilize them is progressing.

[0003] Furthermore, since these light-emitting devices can form a continuous two-dimensional light-emitting layer, they can produce light in a planar manner. This is a feature that is difficult to obtain with point light sources such as incandescent bulbs or LEDs, or line light sources such as fluorescent lamps, and therefore has high value as a planar light source that can be applied to lighting and other applications.

[0004] While displays and lighting devices using light-emitting devices are suitable for various electronic devices, there is still room for improvement in their performance and cost competitiveness. Therefore, there is a growing demand for materials with better properties and easier handling, as well as easy synthesis methods for such materials (see, for example, Non-Patent Document 1).

[0005] Furthermore, the attenuation of light due to reflection caused by differences in refractive index between adjacent layers is a major factor in reducing the luminous efficiency of light-emitting elements. To mitigate this effect, a configuration has been proposed in which a thin film with a low refractive index is formed inside the EL layer (see, for example, Non-Patent Document 2).

[0006] Hiroshi Noguchi, et al., "Orientational Polarization Phenomena of Polar Molecules and Interface Properties of Organic Thin Film Devices," Journal of the Vacuum Society of Japan, 2015, Vol. 58, No. 3. Jaeho Lee, et al., "Synergistic electrode architecture for effective graphene-based flexible organic light-emitting diodes," nature communications, June 2, 2016, DOI: 10.1038 / ncomms11791. 1. Yutaka Noguchi, et al., "Spontaneous orientation polarization in organic light-emitting diodes," Japanese Journal of Applied Physics 58, 2019, SF0801

[0007] One aspect of the present invention aims to provide a novel organic compound. Alternatively, one aspect of the present invention aims to provide a method for synthesizing a novel organic compound. Alternatively, one aspect of the present invention aims to provide an organic compound capable of forming a film with a low refractive index. Alternatively, one aspect of the present invention aims to provide an organic compound capable of forming a film with a low refractive index and high carrier transport properties. Alternatively, one aspect of the present invention aims to provide an organic compound capable of forming a film with a low refractive index and high electron transport properties.

[0008] Furthermore, one aspect of the present invention aims to provide an organic compound that can be used in a light-emitting device. Another aspect of the present invention aims to provide a light-emitting device with high luminous efficiency. Alternatively, one aspect of the present invention aims to provide a light-emitting device with high color purity. Alternatively, one aspect of the present invention aims to provide a light-emitting device with good reliability. Alternatively, one aspect aims to provide any of a display device, electronic device, or lighting device with low power consumption. Alternatively, one aspect aims to provide any of a display device, electronic device, or lighting device with high reliability. Alternatively, one aspect aims to provide any of a display device, electronic device, or lighting device with high color purity.

[0009] The present invention only needs to solve one of the above-mentioned problems.

[0010] One aspect of the present invention is an organic compound represented by the general formula (G1).

[0011]

[0012] In the above formula, A represents a substituted or unsubstituted spirobifluorenyl group, and R １ ~R ５ This represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one of these represents a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms.

[0013] One aspect of the present invention is an organic compound represented by the general formula (G2).

[0014]

[0015] In the above formula, R １ ~R ５ R represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one represents a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms. ６ ~R ８represents any one of hydrogen (including deuterium), a linear alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one represents a linear alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms.

[0016] Further, the organic compound represented by the general formula (G1) or the general formula (G2) has a plurality of hydrocarbon groups selected from a linear alkyl group having 3 to 6 carbon atoms and a cyclic alkyl group having 3 to 10 carbon atoms, and the sp ３ The ratio of the total number of carbon atoms forming bonds with hybrid orbitals is 10% or more and 50% or less.

[0017] One aspect of the present invention is an organic compound represented by structural formula (100) or structural formula (105).

[0018]

[0019] One aspect of the present invention is an organic compound represented by general formula (g1).

[0020]

[0021] In the above formula, X represents a halogen, and R １ [[ID=ZZ]] to R ５ represents any one of hydrogen (including deuterium), a linear alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one represents a linear alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms.

[0022] One aspect of the present invention is an organic compound represented by general formula (g2).

[0023]

[0024] In the above formula, X represents a halogen, and R [[ID=ZZ]] ２ and R ４ each independently represent any one of a linear alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms.

[0025] One aspect of the present invention is an organic compound represented by structural formula (200).

[0026]

[0027] Alternatively, another aspect of the present invention is a display device comprising the light-emitting device described in any of the above.

[0028] Alternatively, another aspect of the present invention is an electronic device having the above-mentioned light-emitting device and a sensor, an operating button, a speaker, or a microphone.

[0029] Alternatively, another aspect of the present invention is a lighting device having the above-mentioned light-emitting device and a housing.

[0030] According to one aspect of the present invention, a novel organic compound can be provided. According to one aspect of the present invention, a method for synthesizing a novel organic compound can be provided. Furthermore, according to one aspect of the present invention, an organic compound that can be used in light-emitting devices can be provided. Alternatively, according to one aspect of the present invention, an organic compound that can form a film with a low refractive index can be provided. Alternatively, according to one aspect of the present invention, an organic compound that can form a film with a low refractive index and high carrier transport properties can be provided. Alternatively, according to one aspect of the present invention, an organic compound that can form a film with a low refractive index and high electron transport properties can be provided.

[0031] Furthermore, in one aspect of the present invention, a light-emitting device with high luminous efficiency can be provided. Alternatively, in one aspect of the present invention, a light-emitting device with high color purity can be provided. Alternatively, in one aspect of the present invention, a light-emitting device with good reliability can be provided. Alternatively, any of a display device, electronic device, or lighting device with low power consumption can be provided. Alternatively, any of a display device, electronic device, or lighting device with high reliability can be provided. Alternatively, any of a display device, electronic device, or lighting device with high color purity can be provided.

[0032] Furthermore, the description of these effects does not preclude the existence of other effects. Moreover, one aspect of the present invention does not necessarily have to possess all of these effects. Other effects will naturally become apparent from the description in the specification, drawings, and claims, and it is possible to extract other effects from the description in the specification, drawings, and claims.

[0033] Figures 1A and 1B are schematic diagrams of the light-emitting device. Figure 2 is a diagram showing the capacitance-voltage characteristics of the measuring device 1. Figure 3 is a diagram showing the current density-voltage characteristics of the measuring device 1. Figures 4A, 4B, 4C, 4D, and 4E are diagrams illustrating the configuration of the light-emitting device. Figures 5A and 5B are top views and cross-sectional views of the light-emitting device. Figures 6A, 6B, 6C, 6D, and 6E are cross-sectional views showing an example of a method for manufacturing a display device. Figures 7A and 7B are cross-sectional views showing an example of a method for manufacturing a display device. Figures 8A, 8B, 8C, and 8D are cross-sectional views showing an example of a method for manufacturing a display device. Figures 9A, 9B, and 9C are cross-sectional views showing an example of a method for manufacturing a display device. Figures 10A, 10B, and 10C are cross-sectional views showing an example of a method for manufacturing a display device. Figures 11A, 11B, and 11C are cross-sectional views showing an example of a method for manufacturing a display device. Figures 12A, 12B, 12C, 12D, 12E, 12F, and 12G are top views showing examples of pixel configurations. Figures 13A, 13B, 13C, 13D, 13E, 13F, 13G, 13H, and 13I are top views showing examples of pixel configurations. Figures 14A and 14B are perspective views showing examples of display module configurations. Figures 15A and 15B are cross-sectional views showing examples of display device configurations. Figure 16 is a perspective view showing an example of display device configuration. Figure 17 is a cross-sectional view showing an example of display device configuration. Figure 18 is a cross-sectional view showing an example of display device configuration. Figure 19A is a cross-sectional view showing an example of display device configuration, and Figures 19B and 19C are top views showing examples of display device configurations. Figure 20 is a cross-sectional view showing an example of display device configuration. Figure 21A is a cross-sectional view showing an example of display device configuration, and Figures 21B and 21C are top views showing examples of display device configurations. Figures 22A, 22B, 22C, and 22D show examples of electronic devices. Figures 23A, 23B, 23C, 23D, 23E, and 23F show examples of electronic devices. Figures 24A, 24B, 24C, 24D, 24E, 24F, and 24G show examples of electronic devices. Figure 25 shows organic compounds. １ This is a diagram showing the 1H NMR spectrum. Figure 26 shows the spectrum of tBu-SFTZn-04. １Figure 27 shows the 1H NMR spectrum. Figure 28 shows the absorption and emission spectra of an organic compound in a toluene solution. Figure 29 shows the results of measuring the refractive index of a film made of tBu-SFTZn-04. Figure 30 shows the results of measuring the refractive index of a film made of tBu-SFTZn-05. Figure 31 shows the results of measuring the refractive index of a film made of tBu-SFTZn. Figure 32 shows the results of measuring the refractive index of a film made of SF2-TRZ. Figure 33 shows the device structure of the light-emitting device 1. Figure 34 shows the luminance-current density characteristics of the light-emitting device 1. Figure 35 shows the luminance-voltage characteristics of the light-emitting device 1. Figure 36 shows the current efficiency-luminance characteristics of the light-emitting device 1. Figure 37 shows the current density-voltage characteristics of the light-emitting device 1. Figure 38 shows the power efficiency-luminance characteristics of the light-emitting device 1. Figure 39 shows the external quantum efficiency-luminance characteristics of the light-emitting device 1. Figure 40 shows the blue index-luminance characteristics of the light-emitting device 1. Figure 41 shows the electroluminescence spectrum of the light-emitting device 1. Figure 42A shows the fluorescence spectrum (10K) of 3,10PCA2Nbf(IV)-02, and Figure 42B shows the phosphorescence spectrum (10K) of 3,10PCA2Nbf(IV)-02. Figure 43 shows the device structure of the light-emitting device 2. Figure 44 shows the luminance-current density characteristics of the light-emitting device 2. Figure 45 shows the luminance-voltage characteristics of the light-emitting device 2. Figure 46 shows the current efficiency-luminance characteristics of the light-emitting device 2. Figure 47 shows the current density-voltage characteristics of the light-emitting device 2. Figure 48 shows the power efficiency-luminance characteristics of the light-emitting device 2. Figure 49 shows the external quantum efficiency-luminance characteristics of the light-emitting device 2. Figure 50 shows the electroluminescence spectrum of the light-emitting device 2. Figure 51 shows the normalized luminance time-varying characteristics of the light-emitting device 2. Figure 52 shows the luminance-current density characteristics of the light-emitting device 3. Figure 53 shows the luminance-voltage characteristics of the light-emitting device 3.Figure 54 shows the current efficiency-luminance characteristics of the light-emitting device 3. Figure 55 shows the current density-voltage characteristics of the light-emitting device 3. Figure 56 shows the power efficiency-luminance characteristics of the light-emitting device 3. Figure 57 shows the external quantum efficiency-luminance characteristics of the light-emitting device 3. Figure 58 shows the field emission spectrum of the light-emitting device 3. Figure 59 shows the tBu-SFTZn-05. １ Figure 60 shows the 1H NMR spectrum. Figure 61 shows the absorption and emission spectra of an organic compound in a toluene solution. Figure 62 shows the luminance-current density characteristics of the light-emitting device 4. Figure 63 shows the luminance-voltage characteristics of the light-emitting device 4. Figure 64 shows the current efficiency-luminance characteristics of the light-emitting device 4. Figure 65 shows the current density-voltage characteristics of the light-emitting device 4. Figure 66 shows the power efficiency-luminance characteristics of the light-emitting device 4. Figure 67 shows the external quantum efficiency-luminance characteristics of the light-emitting device 4. Figure 68 shows the blue index-luminance characteristics of the light-emitting device 4. Figure 69 shows the electroluminescence spectrum of the light-emitting device 4. Figure 70 shows the normalized luminance time-varying characteristics of the light-emitting device 4. Figure 71 shows the luminance-current density characteristics of the light-emitting device 5. Figure 72 shows the luminance-voltage characteristics of the light-emitting device 5. Figure 73 shows the current efficiency-luminance characteristics of the light-emitting device 5. Figure 74 shows the current density-voltage characteristics of the light-emitting device 5. Figure 75 shows the power efficiency-luminance characteristics of the light-emitting device 5. Figure 76 shows the external quantum efficiency-luminance characteristics of the light-emitting device 5. Figure 77 shows the field emission spectrum of the light-emitting device 5. Figure 78 shows the normalized luminance time variation characteristics of the light-emitting device 5.

[0034] The embodiments of the present invention will be described in detail below with reference to the drawings. However, it will be readily apparent to those skilled in the art that the present invention is not limited to the following description, and that its form and details can be modified in various ways without departing from the spirit and scope of the present invention. Accordingly, the present invention shall not be interpreted as being limited to the contents of the embodiments shown below.

[0035] In this specification, devices fabricated using a metal mask or FMM (Fine Metal Mask, a high-resolution metal mask) may be referred to as MM (metal mask) structured devices. In addition, in this specification, devices fabricated without using a metal mask or FMM may be referred to as MML (metal maskless) structured devices.

[0036] (Embodiment 1) This embodiment describes an organic compound that is one aspect of the present invention.

[0037] Among organic compounds that can be used in carrier transport layers of light-emitting devices, 1,1-bis{4-[N,N-di(p-tolyl)amino]phenyl}cyclohexane (abbreviated as TAPC) is known as one of the organic compounds that form films with a low refractive index. It is known that using a film with a low refractive index in the EL (Electroluminescence) layer can increase the external quantum efficiency of the light-emitting device, and therefore, light-emitting devices with good external quantum efficiency can be obtained by using TAPC. However, TAPC has a low glass transition temperature, which gives it problems with heat resistance. Also, while a film made of TAPC can carry holes, it is practically impossible to carry electrons.

[0038] To obtain a film with a low refractive index, it is preferable to introduce atoms with low atomic refraction or substituents with low molecular refraction into the molecules of the organic compound used in the film. Examples of substituents with low molecular refraction include chain-type saturated hydrocarbon groups (chain-type alkyl groups) and cyclic saturated hydrocarbon groups (cyclic alkyl groups). Generally, there is a trade-off relationship between the carrier transport properties of a film and its refractive index; increasing carrier transport properties often results in a higher refractive index. This is because the carrier transport properties of a film largely depend on the presence of unsaturated bonds in the organic compound, and films made of organic compounds with many unsaturated bonds tend to have a high refractive index.

[0039] Furthermore, when electron-transporting organic compounds are used in electron transport layers, it is known that they have difficulty exhibiting high stability compared to hole-transporting organic compounds due to the low required LUMO (Lowest Unoccupied Molecular Orbital) level. In addition, the electron mobility of membranes made of electron-transporting organic compounds is often lower than the hole mobility of membranes made of hole-transporting organic compounds. For this reason, introducing saturated hydrocarbon groups into electron-transporting organic compounds has been considered undesirable because it reduces the carrier (electron) transport performance of the membrane.

[0040] However, contrary to these conventional theories, the inventors have discovered an electron-transporting organic compound having a saturated hydrocarbon group that has carrier transport properties and forms a film with a low refractive index. That is, of all the carbon atoms constituting the organic molecule, sp ３ We discovered an organic compound with a triazine skeleton in which the proportion of carbon atoms forming bonds in hybrid orbitals is controlled within a certain range.

[0041] In other words, the organic compound according to one aspect of the present invention is suitable for electron transport layers in photoelectronic devices such as light-emitting devices and photoelectric conversion devices because it possesses both low refractive index optical properties and electron transport properties in a film, and can be used particularly as a material for electron transport layers. Furthermore, the organic compound according to one aspect of the present invention has a substituent, sp ３By optimizing the number of substituents having carbon atoms that form bonds in hybrid orbitals, or by optimizing their substitution positions, it is possible to achieve a film with a low refractive index while maintaining high electron transport properties. Furthermore, in the organic compound, sp ３ By keeping the proportion of carbon atoms forming bonds in hybrid orbitals within a certain range, it is possible to obtain materials for light-emitting devices and electron transport layers that possess not only a low refractive index and high electron transport properties in the film, but also high heat resistance, which is derived from exhibiting a high glass transition temperature.

[0042] Using a film with a low refractive index in the EL layer improves the efficiency of light extraction from the EL layer. Therefore, by using an organic compound according to one aspect of the present invention in the EL layer of a light-emitting device, the luminous efficiency of the light-emitting device can be improved.

[0043] In particular, the organic compound according to one embodiment of the present invention is suitable as an electron transport layer for the EL layer of a light-emitting device because it has high electron transport properties in the film. Furthermore, because the organic compound according to one embodiment of the present invention has a low refractive index in the film, it can improve the efficiency of extracting light obtained from the EL layer, and thus improve the luminous efficiency of the light-emitting device. Moreover, because the organic compound according to one embodiment of the present invention has high electron transport properties and high light (especially visible light) transmittance in the film, it is suitable as an electron transport layer for a photoelectric conversion device.

[0044] <Examples of Organic Compounds> An organic compound according to one aspect of the present invention will be described below. The organic compound according to one aspect of the present invention can be represented by the following general formulas (G1) to (G2).

[0045] <<Example of an organic compound 1>> One aspect of the present invention is an organic compound represented by the general formula (G1).

[0046]

[0047] However, in the above formula, A represents a substituted or unsubstituted spirobifluorenyl group, and R １ ~R ５This represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one of these represents a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms.

[0048] Furthermore, the organic compound represented by the general formula (G1) has multiple hydrocarbon groups selected from chain alkyl groups having 3 to 7 carbon atoms and cyclic alkyl groups having 3 to 10 carbon atoms, and the sp relative to the total number of carbon atoms in the molecule ３ The proportion of carbon atoms forming bonds in hybrid orbitals is between 10% and 50%.

[0049] Here, a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, is a substituent with a low molecular refractive index. By having substituents with low molecular refractive index within the molecule of an organic compound, the refractive index of a film made of the organic compound represented by general formula (G1) can be reduced.

[0050] Furthermore, in organic compounds represented by general formula (G1), sp ３ The proportion of total carbon atoms forming bonds in hybrid orbitals affects the physical properties of the film, such as its refractive index or glass transition temperature. The glass transition temperature can be used as an indicator for evaluating heat resistance. ３ When the proportion of carbon atoms forming bonds in hybrid orbitals increases, the refractive index of the film decreases, which can improve the light extraction efficiency of light-emitting devices using organic compounds represented by the general formula (G1).

[0051] Also, sp ３ When the total number of carbon atoms forming bonds in hybrid orbitals increases, the rotational motion, vibrational motion, and ring inversion motion of the chain or cyclic alkyl group are relatively restricted, which improves the glass transition temperature and enhances heat resistance. The alkyl group is preferably a branched alkyl group such as a tert-butyl group, or a cyclic alkyl group with fewer than 7 members. Therefore, the glass transition temperature of the organic compound represented by general formula (G1) is preferably 120°C or higher, more preferably 130°C or higher, more preferably 140°C or higher, and even more preferably 150°C or higher.

[0052] sp, represented by aromatic rings or heteroaromatic rings ２ Organic compounds with hybrid orbitals ３ When an organic substituent with hybrid orbitals is introduced, generally sp ３ It is not a skeleton with hybrid orbitals, but sp ２ LUMOs are distributed in aromatic rings with hybrid orbitals, or in heteroaromatic rings. Here, sp ３ When fabricating a film using organic compounds with an excess of total carbon atoms forming bonds in hybrid orbitals, the overlap of LUMOs between adjacent molecules in the organic compounds within the film tends to be inhibited, resulting in a decrease in carrier transport properties (such as electron transport and electron injection).

[0053] Therefore, sp relative to the total number of carbon atoms in the molecule ３ The proportion of carbon atoms forming bonds in hybrid orbitals is preferably 10% to 50%, and more preferably 21% to 45%. Furthermore, the sp of the total number of carbon atoms in the molecule is also important. ３ The proportion of carbon atoms forming bonds in hybrid orbitals is preferably between 25% and 40%.

[0054] Furthermore, in the case of an organic compound represented by general formula (G1) that is composed only of light hydrogen １ The 1H-NMR measurement results should preferably show that the integral value of signals less than 4 ppm originating from protons of chain-like alkyl groups or cyclic alkyl groups is 1 to 3 times, more preferably 1.7 to 2.5 times, the integral value of signals of 4 ppm or more originating from protons of aromatic groups including spirobifluorenyl groups and heteroaromatic groups.

[0055] Furthermore, in the case of an organic compound represented by general formula (G1) that contains deuterium １３ The C-NMR measurement results should preferably show at least two, more preferably four or more, signals originating from the carbon of a chain-like alkyl group or a cyclic alkyl group at less than 60 ppm, and 19 to 38 signals originating from the carbon of a spirobifluorenyl group, an aromatic group including a heteroaromatic group, and the carbon of a triazine skeleton at 60 ppm or more.

[0056] Furthermore, the molecular weight of the organic compound represented by general formula (G1) is preferably 500 to 2000. More preferably, it is 700 to 1500, as this results in a higher glass transition temperature (thermal properties) and makes it less prone to decomposition during sublimation purification (deposition).

[0057] Furthermore, within the molecule of the organic compound represented by general formula (G1), two of the three substituents attached to the 2, 4, and 6 positions of the triazine skeleton have phenyl groups, and only one of these two phenyl groups has sp ３ The structure is configured to arrange chain alkyl groups with 3 to 7 carbon atoms or cyclic alkyl groups with 3 to 10 carbon atoms that form bonds in hybrid orbitals. By adopting this arrangement, the sp space occupies the space around the triazine skeleton responsible for electron transport, i.e., the skeleton where LUMO is distributed. ３ The number of carbon atoms forming bonds in hybrid orbitals can be adjusted. This allows for mutual complementarity of LUMO overlap between adjacent molecules in the film, enabling the formation of a film with a low refractive index while maintaining a certain level of electron transport.

[0058] ≪Example 2 of an organic compound≫ Or, an organic compound represented by the general formula (G2).

[0059]

[0060] However, in the formula, R １ ~R ５ R represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one represents a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms. ６ ~R ８ represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one represents a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms.

[0061] Furthermore, the organic compound represented by the above general formula (G2) has multiple hydrocarbon groups selected from chain alkyl groups having 3 to 6 carbon atoms and cyclic alkyl groups having 3 to 10 carbon atoms, and the sp relative to the total number of carbon atoms in the molecule ３ The proportion of total carbon atoms forming bonds in hybrid orbitals is between 10% and 50%.

[0062] In general formula (G2), the spirobifluorenyl group has at least one chain alkyl group having 3 to 7 carbon atoms and one cyclic alkyl group having 3 to 10 carbon atoms, thereby increasing the total number of carbon atoms or the total number of carbon atoms in the molecule. ３ This makes it easier to adjust the ratio of carbon atoms forming bonds in hybrid orbitals, allowing for a reduction in the refractive index of the film or an improvement in its heat resistance. This enables the mutual complementarity of LUMO overlap between adjacent molecules within the film, allowing for the formation of a film with a low refractive index while maintaining a certain level of electron transport. In other words, by intentionally designing and synthesizing similar molecules, it becomes easier to adjust them to exhibit desired physical properties, and organic compounds with mutually complementary electron transport properties can be provided.

[0063] In addition, in general formula (G1) or general formula (G2), R ｎ Specific examples of substituents represented by (where n is any integer) are shown below.

[0064] Specific examples of chain alkyl groups having 3 to 7 carbon atoms include isopropyl group, butyl group, sec-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neopentyl group, hexyl group, isohexyl group, 3-methylpentyl group, 2-methylpentyl group, 2-ethylbutyl group, 1,2-dimethylbutyl group, 2,3-dimethylbutyl group, and the like.

[0065] Furthermore, specific examples of cyclic alkyl groups having 3 to 10 carbon atoms include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, 3,5-dimethylcyclohexyl group, 4,4-dimethylcyclohexyl group, 3,4,5-trimethylcyclohexyl group, 4-isopropylcyclohexyl group, 4-tert-butylcyclohexyl group, cyclodecanyl group, 1-bicyclooctyl group, 2-norbornyl group, 1-adamantyl group, and 2-adamantyl group.

[0066] Furthermore, in general formula (G1) or general formula (G2), hydrogen may be replaced with deuterium as appropriate.

[0067] <Specific Examples> Next, specific examples of organic compounds that are one embodiment of the present invention and have a structure represented by either the above general formula (G1) or general formula (G2) are shown below.

[0068]

[0069]

[0070]

[0071] The organic compounds represented by structural formulas (100) to (123) above are examples of organic compounds represented by either general formula (G1) or general formula (G2), but the organic compounds of one aspect of the present invention are not limited thereto.

[0072] <Method for synthesizing organic compounds> Below, as an example of an organic compound according to one aspect of the present invention, a method for synthesizing an organic compound represented by the following general formula (G1) will be described. Note that various reactions can be applied as the synthesis method for general formula (G1), and the method is not limited to the one described below.

[0073]

[0074] However, in the above formula, A represents a substituted or unsubstituted spirobifluorenyl group, at least one of R1 to R5 represents either a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms, and the other R1 to R5 represent hydrogen (including deuterium).

[0075] Furthermore, the organic compound represented by the above general formula (G1) can be obtained by reacting a dihalogen compound containing a triazine skeleton (B1) with a boronic acid compound (B2), as shown in the synthesis schemes (s-1) and (s-2) below, and then reacting the intermediate (g1) with the boronic acid compound (B3) of A.

[0076]

[0077]

[0078] In the above general formula (B1), X １ and X ２ represents halogen. Also, R １ ~R ５ At least one of the R represents either a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms, and the other R １ ~R ５ A represents hydrogen (including deuterium). Also, A represents a substituted or unsubstituted spirobifluorenyl group, and Y １ and Y ２ The symbol represents a boronic acid, a boronic acid ester, or a cyclic triol borate salt, etc. In addition to lithium salts, potassium salts and sodium salts may also be used for the cyclic triol borate salt.

[0079] Examples of palladium catalysts that can be used in the coupling reactions represented by the above synthesis schemes (s-1) and (s-2) include palladium(II) acetate, tetrakis(triphenylphosphine)palladium(O), bis(triphenylphosphine)palladium(II) dichloride, and allylpalladium(II) chloride (dimer).

[0080] Examples of ligands for the above palladium catalyst include di(1-adamantyl)-n-butylphosphine, (±)-2,2'-bis(diphenylphosphine)-1,1'-binaphthyl, tri(ortho-tolyl)phosphine, triphenylphosphine, tricyclohexylphosphine, and di-tert-butyl(2,2-diphenyl-1-methyl-1-cyclopropyl)phosphine. However, the ligands that can be used are not limited to these.

[0081] Examples of bases that can be used in the coupling reactions represented by the above synthesis schemes (s-1) and (s-2) include organic bases such as potassium-tert-butoxide, and inorganic bases such as potassium carbonate, sodium carbonate, and tripotassium phosphate.

[0082] In the coupling reactions represented by the above synthesis schemes (s-1) and (s-2), suitable solvents include toluene, xylene, mesitylene, benzene, tetrahydrofuran, dioxane, and diethylene glycol dimethyl ether. However, the solvents that can be used are not limited to these.

[0083] Furthermore, the reactions carried out in the above synthesis schemes (s-1) and (s-2) are not limited to the Suzuki-Miyaura reaction, but can also be performed using the Migita-Kosugi-Still coupling reaction with organotin compounds, nucleophilic substitution reactions with Grignard reagents, and the like.

[0084] Furthermore, various types of the aforementioned compounds (B1), (B2), and (B3) are commercially available or can be synthesized.

[0085] In the coupling reaction represented by the above synthesis scheme (s-1), X １ and X ２ To suppress the formation of a disubstituted product resulting from the reaction of both, it is preferable to carry out the reaction at a temperature of 60°C to 80°C. In the coupling reaction represented by the above synthesis scheme (s-2), the organic compound represented by general formula (G1) is X １ or X ２To suppress the amount of halogen detected when unreacted residues remain and to obtain a high-purity product, it is preferable to add an excess amount of the boronic acid compound A (B3) and carry out the reaction.

[0086] While organic compounds according to one aspect of the present invention can be synthesized as described above, the present invention is not limited thereto, and may be synthesized by other synthesis methods.

[0087] <Specific Examples Represented by Organic Compound (g1)> Below are specific examples of organic compounds that have the structure represented by the above general formula (g1) and represent one aspect of the present invention.

[0088]

[0089] The organic compounds represented by structural formulas (200) to (214) above are examples of organic compounds represented by the general formula (g1) above, but the organic compounds of one aspect of the present invention are not limited thereto.

[0090] This embodiment can be used in any combination with other embodiments and examples.

[0091] (Embodiment 2) This embodiment describes a light-emitting device using the organic compound shown in Embodiment 1.

[0092] <Example of Light-Emitting Device Configuration> Figure 1A is a schematic cross-sectional view of a light-emitting device 10 according to one embodiment of the present invention. The light-emitting device 10 has a pair of electrodes (a first electrode 101 and a second electrode 102) and an organic compound layer 103 provided between the pair of electrodes. The organic compound layer 103 has at least a light-emitting layer 113.

[0093] Furthermore, the organic compound layer 103 shown in Figure 1A has functional layers such as a hole injection layer 111, a hole transport layer 112, an electron transport layer 114, and an electron injection layer 115, in addition to the light-emitting layer 113.

[0094] In this embodiment, the first electrode 101 is described as the anode and the second electrode 102 as the cathode, but the configuration of the light-emitting device 10 is not limited to this. In other words, the first electrode 101 may be the cathode and the second electrode 102 as the anode, and the stacking order of the layers between the electrodes may be reversed. That is, the stacking order from the anode side may be the hole injection layer 111, the hole transport layer 112, the light-emitting layer 113, the electron transport layer 114, and the electron injection layer 115.

[0095] The configuration of the organic compound layer 103 is not limited to the configuration shown in Figure 1A, and may include at least one selected from the hole injection layer 111, hole transport layer 112, electron transport layer 114, and electron injection layer 115. Alternatively, the organic compound layer 103 may include a functional layer that has functions such as reducing the hole or electron injection barrier, improving hole or electron transport, inhibiting hole or electron transport, or suppressing quenching by electrodes. Each functional layer may be a single layer or a configuration in which multiple layers are stacked.

[0096] Figure 1B is a schematic cross-sectional view showing an example of the light-emitting layer 113 shown in Figure 1A. The light-emitting layer 113 shown in Figure 1B comprises a host material 118 (organic compound 118_1 and organic compound 118_2) and a guest material 119 (luminescent substance).

[0097] The guest material 119 can be any luminescent organic compound, and the luminescent organic compound can be a substance that can emit phosphorescence (hereinafter also referred to as a phosphorescent compound) or a substance that can emit fluorescence (hereinafter also referred to as a fluorescent compound).

[0098] Furthermore, in the light-emitting layer 113, the host material 118 is present in the largest amount by weight, and the guest material 119 is dispersed within the host material 118. Note that the lowest triplet excitation energy level (T) of the host material 118 (organic compound 118_1 and organic compound 118_2) in the light-emitting layer 113 is １ The level is the T of the guest material 119 of the light-emitting layer 113. １ It is preferable that the level be higher than the current level.

[0099] Furthermore, it is preferable that the host material 118 (organic compound 118_1 and organic compound 118_2) in the light-emitting layer 113 forms an excited complex (also called an exciplex). An excited complex is an excited state consisting of two or more substances, and in the case of photoexcitation, it is formed by the interaction of one of the substances in the excited state with the other substance in the ground state.

[0100] The organic compound described in Embodiment 1 has good carrier transport properties, and is particularly excellent in electron transport, and can therefore be suitably used as a carrier transport layer, especially an electron transport layer, an electron injection layer, or a host material in a light-emitting device.

[0101] Furthermore, the light-emitting device can improve its light extraction efficiency by using a low refractive index film in the organic compound layer 103. In particular, the organic compound described in Embodiment 1, which has an electron-transporting skeleton and saturated hydrocarbon groups, can form a low refractive index film. Therefore, by using the organic compound described in Embodiment 1 as the material constituting the organic compound layer 103, it is possible to improve the light extraction efficiency and provide a light-emitting device with good current efficiency and external quantum efficiency.

[0102] In vapor-deposited films of organic compounds, the permanent electric dipole moments of molecules may be oriented, resulting in spontaneous orientation polarization (SOP). Furthermore, if the spontaneous orientation polarization is biased in the direction of film thickness, a giant surface potential (GSP) may be generated. Since GSP increases proportionally to the film thickness, a slope of GSP (GSP_slope) exists as a physical property of the layer. GSP_slope is expressed as ΔV / Δd, where the change in surface potential is ΔV (mV) for a change in film thickness Δd (nm). In other words, GSP per unit film thickness is called GSP_slope. Furthermore, if the surface potential increases with increasing film thickness, the GSP_slope will be positive; conversely, if the surface potential decreases with increasing film thickness, the GSP_slope will be negative.

[0103] Furthermore, when layers having different GSP_slope are stacked, it can be assumed that an electric charge is generated at the interface, and this virtual interface charge affects the device characteristics. Therefore, in a light-emitting device, by selecting the materials used for each layer while considering the slope (GSP_slope) of the giant surface potential (GSP) of the light-emitting layer 113 and the layers surrounding the light-emitting layer 113, the interface charge can be controlled, improving the luminous efficiency of the light-emitting device or reducing the driving voltage. Note that the virtual charge that can be considered as an interface charge is sometimes referred to as interface charge in this specification.

[0104] For example, in the case of a light-emitting device in which the guest material 119 is a phosphorescent compound and the device has a light-emitting layer 113 and an electron transport layer 114, it is preferable that a positive interfacial charge is generated at the interface between the light-emitting layer 113 and the electron transport layer 114. Therefore, in the case of a light-emitting device in which the anode is placed on the substrate side (referred to as a forward-stacked device), it is preferable that the GSP_slope of the light-emitting layer 113 is larger than the GSP_slope of the electron transport layer 114. On the other hand, in the case of a light-emitting device in which the cathode is placed on the substrate side (referred to as an inverted-stacked device), it is preferable that the GSP_slope of the light-emitting layer 113 is smaller than the GSP_slope of the electron transport layer 114. With this configuration, electrons injected from the cathode accumulate near the light-emitting layer, making it possible to effectively apply an electric field to the light-emitting layer 113. Therefore, since it becomes easy to effectively apply an electric field to the light-emitting layer 113, the driving voltage of the light-emitting device can be lowered.

[0105] Furthermore, in the case of a light-emitting device in which, for example, the guest material 119 is a fluorescent compound and the light-emitting region is localized near the interface between the light-emitting layer 113 and the electron transport layer 114, thereby effectively utilizing triplet-triplet annihilation (TTA), it is preferable that a negative interfacial charge is generated at the interface between the light-emitting layer 113 and the electron transport layer 114. Therefore, in the case of a forward-stacked device, it is preferable that the GSP_slope of the light-emitting layer 113 is smaller than the GSP_slope of the electron transport layer 114. On the other hand, in the case of a light-emitting device in which the cathode is placed on the substrate side (referred to as a reverse-stacked device), it is preferable that the GSP_slope of the light-emitting layer 113 is larger than the GSP_slope of the electron transport layer 114. This configuration suppresses the injection of electrons from the electron transport layer 114 into the light-emitting layer 113.

[0106] Due to the effects described above, in a light-emitting device where the guest material 119 captures holes and the light-emitting region tends to be biased towards the interface between the light-emitting layer and the hole transport layer, the light-emitting region can be shifted from near the anode interface to the center of the light-emitting layer, thereby suppressing exciton annihilation caused by exciton-polaron interaction with holes accumulated at the anode interface of the light-emitting layer. In addition, it is possible to suppress the excessive supply of electrons to the light-emitting layer and suppress the leakage of electrons from the light-emitting layer to the anode side. On the other hand, this configuration suppresses the accumulation of electrons at the interface between the electron transport layer 114 and the light-emitting layer 113. Due to this effect, in a light-emitting device where the guest material captures electrons and the light-emitting region tends to be biased towards the interface between the light-emitting layer and the electron transport layer, the distance between excitons and accumulated electrons increases, thereby suppressing exciton annihilation caused by exciton-polaron interaction. As a result of these effects, a light-emitting device with high luminescence efficiency can be obtained.

[0107] Furthermore, if the guest material 119 is not a phosphorescent compound or a fluorescent compound, and the electron transport layer 114 is a forward-stacked device having a multilayer structure, it is preferable that the GSP_slope of the electron transport layer provided on the light-emitting layer 113 side is larger than the GSP_slope of the electron transport layer provided on the cathode side. If the electron transport layer 114 is a reverse-stacked device having a multilayer structure, it is preferable that the GSP_slope of the electron transport layer provided on the light-emitting layer 113 side is smaller than the GSP_slope of the electron transport layer provided on the cathode side. With this configuration, electrons injected from the cathode accumulate near the light-emitting layer, making it possible to effectively apply an electric field to the light-emitting layer 113. Therefore, since it becomes easier to effectively apply an electric field to the light-emitting layer 113, the driving voltage of the light-emitting device can be lowered.

[0108] The organic compound described in Embodiment 1 has a GSP_slope of 20 mV / nm or more and 50 mV / nm or less. Therefore, the material can be appropriately selected according to the desired characteristics of the light-emitting device.

[0109] One aspect of the present invention provides a light-emitting device using the organic compound described in Embodiment 1 as an electron-transporting material, or a light-emitting device using the organic compound described in Embodiment 1 as a host material.

[0110] <Method for determining GSP_slope and SOP> Here, we will explain the method for determining the GSP_slope and SOP of a film formed by vacuum deposition of an organic compound.

[0111] First, we will explain how to calculate GSP_slope and SOP in a configuration where the carriers accumulating at the interface are holes. The phenomenon in which the surface potential of a deposited film increases in proportion to the film thickness is called giant surface potential, as mentioned above. Generally, the slope when the surface potential of a deposited film measured by Kelvin probe is plotted in the direction of film thickness is discussed as the magnitude of the giant surface potential, i.e., GSP_slope (mV / nm). However, when two different layers are stacked, the charge density (mC / m) accumulated at their interface... ２ By utilizing the fact that ) changes in relation to GSP, GSP_slope and SOP can be estimated.

[0112] Non-patent document 1 shows that when organic thin films with different spontaneous orientation polarizations (thin film 1 and thin film 2, where thin film 1 is on the anode side and thin film 2 is on the cathode side, and the anode is located on the substrate side) are stacked and a voltage is applied, the following equation holds true if the carriers accumulated at the interface are holes.

[0113]

[0114]

[0115] In equation (1), σ ｉｆ＿ｈ V is the interfacial charge density. ｉ V is the hole injection voltage. ｂｉ d is the threshold voltage, ２ ε is the film thickness of thin film 2. ２ V is the dielectric constant of thin film 2. ｉ , V ｂｉ This can be estimated from the capacitance-voltage characteristics of the device. Furthermore, the dielectric constant is the refractive index n. ｏ The square of (wavelength 633 nm) can be used. In this way, V estimated from the capacitance-voltage characteristics ｉ , V ｂｉ And the dielectric constant ε of thin film 2 calculated from the refractive index. ２ , and the film thickness d of thin film 2 ２ Therefore, using equation (1), the interfacial charge density σ ｉｆ＿ｈ It is possible to find this.

[0116] Next, in equation (2), σ ｉｆ＿ｈ P is the interfacial charge density. ｎ ε is the spontaneous orientation polarization of the thin film n in the direction normal to the substrate. ｎ V is the dielectric constant of the thin film n. ｎ d is the potential of the film surface, ｎ is the thickness of the thin film n. And the potential (V) of the film surface. ｎ ) film thickness (d ｎ The GSP_slope can be calculated from the value obtained by dividing by (1) above. Here, the interface charge density σ ｉｆ＿ｈ Since this can be determined, by using a material with a known GSP_slope as thin film 2 and adopting an appropriate dielectric constant, the GSP_slope and SOP of thin film 1 can be estimated.

[0117] Therefore, as thin film 2, tris(8-quinolinolato)aluminum (abbreviated as Alq) is used, which has a known GSP_slope of 48 (mV / nm). ３ An example of how a measurement device 1 was fabricated using the above method and how the GSP_slope and SOP of 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as NPB) were determined is shown below.

[0118] The device structure of measurement device 1 is shown in Table 1. The cathode from layer 1_1 of measurement device 1 was formed by vacuum deposition from the anode side, with the substrate temperature at room temperature and the deposition rate from 0.2 nm / s to 0.6 nm / s. Deposition was carried out without stopping the deposition process while forming one layer. In measurement device 1, layer 2_1 corresponds to thin film 1, and layer 3_1 corresponds to thin film 2. OCHD-003 is an organic compound that has electron acceptor properties.

[0119] When fabricating the measurement device, the deposition rate of each layer is preferably 3 nm / min to 600 nm / min. Furthermore, the film thickness of each layer in the measurement device is preferably 3 nm to 500 nm, and more preferably 50 nm to 300 nm.

[0120] Furthermore, the capacitance-voltage characteristics of the measuring device 1 are shown in Figure 2.

[0121]

[0122] Table 2 shows the Hole injection voltage V of the measuring device 1, which was determined using Figure 2 and equations (1) and (2). ｉ , threshold voltage V ｂｉ , interfacial charge density σ ｉｆ＿ｈ , GSP_slope and the refractive index n of the NPB used in the calculation ｏ and Alq ３ refractive index n ｏ This shows the results. The refractive index was measured using a spectroscopic ellipsometer (M-2000U, manufactured by J.A. Woolam Japan Co., Ltd.).

[0123]

[0124] Furthermore, it has almost the same configuration as the measurement device 1, Alq３ A measurement device 2 with a film thickness of only 80 nm was fabricated, and it was confirmed that the hole injection voltage was shifted to a lower voltage than that of the measurement device 1. That is, in such a device, holes are injected first, and it is suggested that charges are accumulated at the interface with Alq ３ . Also, using the measurement device 2, an estimation of GSP_slope and SOP was performed in the same manner as for the measurement device 1, and it was confirmed that the results were equivalent.

[0125] Also, when it is difficult to determine the threshold voltage V from the capacitance-voltage characteristics, the threshold voltage of the current density-voltage characteristics may be adopted. ｂｉ

[0126] The current density-voltage characteristics of the measurement device 1 are shown in FIG. 3.

[0127] V calculated from the current density-voltage characteristics ｂｉ was 2.0 V, showing the same value as the value calculated from the capacitance-voltage characteristics.

[0128] Thus, by fabricating a device in which a film of Alq with a known GSP_slope of the film and a film formed of an organic compound for which GSP_slope and SOP are to be determined are laminated, and measuring the capacitance-voltage characteristics, GSP_slope and SOP can be estimated. ３

[0129] In the above description, a method for calculating GSP_slope and SOP in a configuration where the carriers accumulated at the interface are holes has been described. However, when determining the GSP_slope and SOP of an organic film in a configuration where the carriers accumulated at the interface are electrons, the following equations (3) and (4) can be used for the same calculation. In the following equations (3) and (4), σ ｉｆ＿ｅ is the interfacial charge density.

[0130]

[0131]

[0132] It is preferable to select an organic compound to be used for each layer of the light-emitting device in consideration of the GSP_slope and SOP of the vapor-deposited film of the organic compound measured in advance by the above measurement method.

[0133] In some cases, light-emitting devices use layers co-deposited with multiple types of organic compounds. Since the GSP_slope of a co-deposited layer changes depending on the combination and mixing ratio of the organic compounds, it is ideal to measure the GSP_slope of films co-deposited with the same combination and mixing ratio of organic compounds in advance, and then select the organic compounds considering this GSP_slope. However, this method requires fabricating different co-deposited films for each combination or mixing ratio of organic compounds and measuring the GSP_slope for each, making the experiments for selecting organic compounds complicated.

[0134] Therefore, in a light-emitting device, if one layer contains multiple types of organic compounds, it is preferable to select the organic compounds by considering the average value of the GSP_slope of the deposited film of each organic compound, which has been measured in advance, as the GSP_slope of that layer. This makes it relatively easy to select organic compounds that take GSP_slope into consideration.

[0135] However, even if a single layer contains multiple types of organic compounds, if their content differs significantly, the GSP_slope of the vapor-deposited film of the organic compound with the highest content among the multiple types of organic compounds can be considered as the GSP_slope of that layer, and the selection of organic compounds can be performed accordingly. For example, if a single layer contains two types of organic compounds, and the content of one organic compound is less than 20% by weight of the total, that organic compound can be judged as a minor component of that layer, and the other, more abundant organic compound can be judged as the main component of that layer, and the GSP_slope of the vapor-deposited film of that main component can be considered as the GSP_slope of that layer. Also, if a single layer contains three or four types of organic compounds, and the content of one organic compound is less than 20% by weight of the total, that organic compound can be judged as a minor component of that layer, and the remaining organic compounds can be judged as the main components of that layer, and the average value of the GSP_slope of the vapor-deposited films of each main component can be considered as the GSP_slope of that layer. Furthermore, SOP can be considered in the same way as GSP_slope.

[0136] <Basic Structure of Light-Emitting Devices> Below, the basic structure of light-emitting devices will be explained in more detail using Figures 4A to 4E. Figure 4A shows a light-emitting device with a structure (single structure) having an organic compound layer (also called an EL layer) containing a light-emitting layer between a pair of electrodes. Specifically, it has a structure in which an organic compound layer 103 is sandwiched between a first electrode 101 and a second electrode 102.

[0137] Furthermore, Figure 4B shows a light-emitting device with a laminated structure (tandem structure) having multiple (two layers in Figure 4B) organic compound layers (103a, 103b) between a pair of electrodes, and a charge generation layer 106 between the organic compound layers. A light-emitting device with a tandem structure can realize a highly efficient light-emitting device without changing the amount of current.

[0138] The charge generation layer 106 has the function of injecting electrons into one organic compound layer (103a or 103b) and holes into the other organic compound layer (103b or 103a) when a potential difference is created between the first electrode 101 and the second electrode 102. Therefore, in Figure 4B, when a voltage is applied to the first electrode 101 such that its potential is higher than that of the second electrode 102, electrons are injected from the charge generation layer 106 into the organic compound layer 103a and holes are injected into the organic compound layer 103b.

[0139] Furthermore, from the viewpoint of light extraction efficiency, it is preferable that the charge generation layer 106 is transparent to visible light (specifically, the transmittance of visible light to the charge generation layer 106 is 40% or more). In addition, the charge generation layer 106 can function even if its conductivity is lower than that of the first electrode 101 and the second electrode 102.

[0140] Figure 4C shows the laminated structure of the organic compound layer 103 of a light-emitting device according to one embodiment of the present invention. In this case, the first electrode 101 functions as an anode and the second electrode 102 functions as a cathode. The organic compound layer 103 has a structure in which a hole injection layer 111, a hole transport layer 112, a light-emitting layer 113, an electron transport layer 114, and an electron injection layer 115 are sequentially laminated on the first electrode 101. The light-emitting layer 113 may be configured by laminating multiple light-emitting layers with different emission colors. For example, a light-emitting layer containing a red light-emitting substance, a light-emitting layer containing a green light-emitting substance, and a light-emitting layer containing a blue light-emitting substance may be laminated, or laminated via a layer having a carrier transport material. Alternatively, a combination of a light-emitting layer containing a yellow light-emitting substance and a light-emitting layer containing a blue light-emitting substance may be used. However, the laminated structure of the light-emitting layer 113 is not limited to the above. For example, the light-emitting layer 113 may be configured by stacking multiple light-emitting layers of the same emission color. For example, it may be a structure in which a first light-emitting layer containing a blue light-emitting substance and a second light-emitting layer containing a blue light-emitting substance are stacked, or stacked via a layer having a carrier transport material. In the case of a configuration in which multiple light-emitting layers of the same emission color are stacked, reliability can be increased compared to a single-layer configuration. Also, even when there are multiple light-emitting layers as in the tandem structure shown in Figure 4B, each light-emitting layer is stacked sequentially from the anode side as described above. Furthermore, when the first electrode 101 is the cathode and the second electrode 102 is the anode, the stacking order of the organic compound layer 103 is reversed. Specifically, on the first electrode 101 which is the cathode, 111 is an electron injection layer, 112 is an electron transport layer, 113 is a light-emitting layer, 114 is a hole transport layer, and 115 is a hole injection layer.

[0141] The light-emitting layers 113 contained in the organic compound layers (103, 103a, 103b) each contain a light-emitting substance and a combination of multiple substances as appropriate, and can be configured to produce fluorescence emission or phosphorescence emission exhibiting a desired emission color. Alternatively, the light-emitting layers 113 may be arranged in a laminated structure with different emission colors. In this case, the light-emitting substance and other substances used in each laminated light-emitting layer may be made of different materials. Furthermore, a configuration may be used in which different emission colors can be obtained from multiple organic compound layers (103a, 103b) as shown in Figure 4B. In this case as well, the light-emitting substance and other substances used in each light-emitting layer may be made of different materials.

[0142] Furthermore, in a light-emitting device according to one aspect of the present invention, for example, by using a reflective electrode as the first electrode 101 shown in Figure 4C and a semi-transparent / semi-reflective electrode as the second electrode 102, and by using a microcavity structure, the light emitted from the light-emitting layer 113 contained in the organic compound layer 103 can be resonated between the two electrodes, thereby strengthening the light emitted from the second electrode 102. Therefore, it is easy to achieve high resolution. In addition, since it is possible to strengthen the light emission intensity in the front direction at a specific wavelength, power consumption can be reduced.

[0143] Furthermore, if the first electrode 101 of the light-emitting device is a reflective electrode consisting of a laminated structure of a reflective conductive material and a translucent conductive material (transparent conductive film), optical adjustment can be performed by controlling the film thickness of the transparent conductive film. Specifically, it is preferable to adjust the optical distance (product of film thickness and refractive index) between the first electrode 101 and the second electrode 102 to be mλ / 2 (where m is an integer of 1 or more) or close to it, with respect to the wavelength λ of light obtained from the light-emitting layer 113.

[0144] Furthermore, in order to amplify the light obtained from the light-emitting layer 113 at a desired wavelength (wavelength: λ), it is preferable to adjust the optical distance from the first electrode 101 to the region where light emission is obtained in the light-emitting layer 113 (light-emitting region), and the optical distance from the second electrode 102 to the region where light emission is obtained in the light-emitting layer 113 (light-emitting region), so that they are (2m'+1)λ / 4 (where m' is an integer of 1 or more) or near that value. The light-emitting region referred to here is the region in the light-emitting layer 113 where holes and electrons recombine.

[0145] By performing such optical adjustments, the spectrum of specific monochromatic light obtained from the light-emitting layer 113 can be narrowed, resulting in light emission with good color purity.

[0146] However, in the above case, the optical distance between the first electrode 101 and the second electrode 102 can be precisely defined as the total thickness from the reflective region of the first electrode 101 to the reflective region of the second electrode 102. However, since it is difficult to precisely determine the reflective regions of the first electrode 101 and the second electrode 102, the above effects can be sufficiently obtained by assuming that any position on the first electrode 101 and the second electrode 102 is a reflective region. Furthermore, the optical distance between the first electrode 101 and the light-emitting layer can be precisely defined as the optical distance between the reflective region of the first electrode 101 and the light-emitting region of the light-emitting layer. However, since it is difficult to precisely determine the reflective region of the first electrode 101 and the light-emitting region of the light-emitting layer, the above effects can be sufficiently obtained by assuming that any position on the first electrode 101 is a reflective region and any position on the light-emitting layer is a light-emitting region.

[0147] The light-emitting device shown in Figure 4D is a light-emitting device having a tandem structure. The tandem structure allows for a light-emitting device capable of high-brightness illumination. Furthermore, compared to a single structure, the tandem structure reduces the current required to achieve the same brightness, thereby improving reliability. It also reduces power consumption.

[0148] The light-emitting device shown in Figure 4E is an example of a tandem-structured light-emitting device shown in Figure 4B. As shown in the figure, it has a structure in which three organic compound layers (103a, 103b, 103c) are stacked with charge generation layers (106a, 106b) in between. Each of the three organic compound layers (103a, 103b, 103c) has a light-emitting layer (113a, 113b, 113c), and the light-emitting colors of each light-emitting layer can be freely combined. For example, light-emitting layer 113a can be blue, light-emitting layer 113b can be red, green, or yellow, and light-emitting layer 113c can be blue. Alternatively, light-emitting layer 113a can be red, light-emitting layer 113b can be blue, green, or yellow, and light-emitting layer 113c can be red.

[0149] In the light-emitting device according to one aspect of the present invention described above, at least one of the first electrode 101 and the second electrode 102 is a light-transmitting electrode (such as a transparent electrode or a semi-transparent / semi-reflective electrode). When the light-transmitting electrode is a transparent electrode, the visible light transmittance of the transparent electrode is 40% or more. When it is a semi-transparent / semi-reflective electrode, the visible light reflectance of the semi-transparent / semi-reflective electrode is 20% or more and 80% or less, preferably 40% or more and 70% or less. Furthermore, these electrodes have a resistivity of 1 × 10⁻¹⁶. −２ It is preferable to keep it below Ωcm.

[0150] Furthermore, in the light-emitting device according to one aspect of the present invention described above, if one of the first electrode 101 and the second electrode 102 is a reflective electrode (reflective electrode), the visible light reflectance of the reflective electrode is 40% or more and 100% or less, preferably 70% or more and 100% or less. Also, the resistivity of this electrode is 1 × 10⁻¹⁶. −２ It is preferable to keep it below Ωcm.

[0151] <Specific Structure of the Light-Emitting Device> Next, a specific structure of a light-emitting device according to one aspect of the present invention will be described. Here, the explanation will be given using Figure 4D, which has a tandem structure. The same applies to the configuration of the organic compound layer for the single-structure light-emitting devices shown in Figures 4A and 4C. Furthermore, if the light-emitting device shown in Figure 4D has a microcavity structure, the first electrode 101 is formed as a reflective electrode, and the second electrode 102 is formed as a semi-transparent / semi-reflective electrode. Thus, one or more desired electrode materials can be used and formed in a single layer or in a stacked manner. The second electrode 102 is formed by selecting an appropriate material after the organic compound layer 103b has been formed.

[0152] <Materials for Light-Emitting Devices> <Light-Emitting Layers> The light-emitting layers (113, 113a, 113b) are layers containing a light-emitting material. The light-emitting material that can be used in the light-emitting layers (113, 113a, 113b) can be any material that exhibits a light-emitting color such as blue, purple, blue-violet, green, yellow-green, yellow, orange, or red. Furthermore, if there are multiple light-emitting layers, a configuration exhibiting different light-emitting colors can be achieved by using different light-emitting materials in each layer (for example, white light emission obtained by combining complementary light-emitting colors). Additionally, a laminated structure in which one light-emitting layer contains a different light-emitting material is also possible.

[0153] Furthermore, the light-emitting layers (113, 113a, 113b) may contain one or more types of organic compounds (host materials, etc.) in addition to the light-emitting substance (guest material).

[0154] For example, the structure described with reference to Figure 1B can be used as the light-emitting layer 113. In the light-emitting layer 113, the host material 118 is present in the largest amount by weight, and the guest material 119 is dispersed in the host material 118. As the guest material 119, phosphorescent compounds or fluorescent compounds can be used. Mechanisms for efficiently emitting fluorescent compounds include TTA (triplet-triplet annealing) and TADF (thermally activated delayed fluorescent emission), and these mechanisms can be adopted as needed.

[0155] Next, a preferred configuration of the light-emitting layer 113 using a phosphorescent compound as the guest material 119 will be described.

[0156] In the light-emitting layer 113 using a phosphorescent compound as the guest material 119, the T １ level of the host material 118 (organic compound 118_1 and organic compound 118_2) is preferably higher than the T １ level of the guest material (guest material 119) of the light-emitting layer 113.

[0157] Note that the lowest triplet excitation energy level (T １ level) can be calculated from the emission end of the phosphorescence spectrum. Also, a compound whose phosphorescence spectrum is not detected at room temperature may be detected by being in a low-temperature state (for example, any temperature in the range from 4 K to 80 K). Also, the sample form when measuring the emission spectrum of the luminescent center substance may be a thin film or a solution, but from the viewpoint of verifying the state of isolated molecules, a solution is preferred. As the solvent of the solution, a solvent with relatively low polarity such as toluene or chloroform is preferred. Also, in the case of a phosphorescent compound employed as the luminescent center substance, a phosphorescence spectrum is observed even at room temperature. Therefore, the temperature for measuring the lowest triplet excitation energy level (T １ level) may be either a low temperature (for example, any temperature in the range from 4 K to 80 K) or room temperature (for example, 298 K). Note that the emission end can be calculated from the intersection of the tangent line drawn 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 maximum and the horizontal axis (wavelength) or the baseline.

[0158] If no phosphorescence component is confirmed in the PL spectrum observed even at low temperature in a thin film containing only the material to be measured or a solution to which only the material to be measured is added, a phosphorescence sensitizer may be added. The phosphorescence sensitizer can be a phosphorescent material having a T １ level higher than that of the material to be measured. Specifically, Ir(ppy) ３ etc. can be used.

[0159] Examples of materials that can be used as compounds exhibiting phosphorescence in the light-emitting layer 113 include the following. Other phosphorescent substances can also be used.

[0160] Tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazole-3-yl-κN2]phenyl-κC}Iridium(III) (Abbreviation: [Ir(mpptz-dmp) ３ ]), Tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazolato) iridium (III) (abbreviation: [Ir(Mptz) ３ ]) an organometallic iridium complex having a 4H-triazole skeleton, such as tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(Mptz1-mp) ３ ]), Tris(1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato) Iridium(III) (abbreviation: [Ir(Prptz1-Me) ３ ]) an organometallic iridium complex having a 1H-triazole skeleton, such as 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]phenanthridine]iridium(III) (abbreviation: [Ir(dmpimpt-Me) ３ ]), organometallic iridium complexes having an imidazole skeleton such as tris(2-{1-[2,6-bis(1-methylethyl)phenyl]-1H-imidazole-2-yl-κN3}-4-cyanophenyl-κC) iridium(III) (abbreviation: CNImIr), tris[(6-tert-butyl-3-phenyl-2H-imidazol[4,5-b]pyrazine-1-yl-κC2)phenyl-κC] iridium(III) (abbreviation: [Ir(cb) ３ ]) an organoiridium complex having a benzimidazolidene skeleton, bis[2-(4',6'-difluorophenyl)pyridinato-N,C ２’Iridium(III) tetrakis(1-pyrazolyl) borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinate-N,C ２’ Iridium(III) picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinate-N,C ２’ Iridium (III) picolinate (abbreviation: [Ir(CF ３ ppy) ２ (pic)]), bis[2-(4',6'-difluorophenyl)pyridinate-N,C ２’ Examples include organometallic iridium complexes with phenylpyridine derivatives having electron-withdrawing groups, such as iridium(III) acetylacetonate (abbreviated as FIr(acac)), and platinum complexes such as (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazole-1-yl-2-ylidene-κC2]phenoxy-κC2}-9-(4-tert-butyl-2-pyridinyl-κN)carbazole-2,1-diyl-κC1)platinum(II) (abbreviated as PtON-TBBI). These compounds exhibit blue phosphorescence and have emission peaks in the wavelength range from 440 nm to 520 nm. Among those mentioned above, organometallic iridium and platinum complexes having nitrogen-containing five-membered heterocyclic skeletons such as the 4H-triazole, 1H-triazole, and imidazole skeletons are particularly preferred because they have high triplet excitation energy and excellent reliability or luminescence efficiency. Compounds in which some of the hydrogen atoms in these compounds are replaced with deuterium can also be used.

[0161] Also, tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm) ３ ]), Tris(4-t-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)), (acetylacetonate)bis[6-(2-norbornyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(nbppm) ２ (acac)), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(mpmpppm) ２ (acac)), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm) ２ Organometallic iridium complexes having a pyrimidine skeleton such as (acac) (acetylacetonato)bis(3,5-dimethyl-2-phenylpyradinato)iridium(III) (abbreviation: [Ir(mppr-Me) ２ (acac)), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyradinato)iridium(III) (abbreviation: [Ir(mppr-iPr) ２ Organometallic iridium complexes having a pyrazine skeleton such as (acac), Tris(2-phenylpyridinato-N,C) ２’ Iridium (III) (abbreviation: [Ir(ppy) ３ ]), bis(2-phenylpyridinate-N,C ２’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(ppy) ２ (acac)), bis(benzo[h]quinolinate)iridium(III)acetylacetonate (abbreviation: [Ir(bzq) ２ (acac)), Tris(benzo[h]quinolinate) 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-d3-methyl-8-(2-pyridinyl-κN)benzofl[2,3-b]pyridine-κC]bis[2-(5-d3-methyl-2-pyridinyl-κN2)phenyl-κC]iridium(III) (abbreviation: Ir(5mppy-d3) ２ (mbfpypy-d3), {2-(methyl-d3)-8-[4-(1-methylethyl-1-d)-2-pyridinyl-κN]benzofl[2,3-b]pyridin-7-yl-κC}bis{5-(methyl-d3)-2-[5-(methyl-d3)-2-pyridinyl-κN]phenyl-κC}Iridium(III) (abbreviation: Ir(5mtpy-d6) ２ (mbfpypy-iPr-d4)), [2-(methyl-d3)-8-(2-pyridinyl-κN)benzofl[2,3-b]pyridine-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy) ２ (mbfpypy-d3)), [2-(4-d3-methyl-5-phenyl-2-pyridinyl-κN2)phenyl-κC]bis[2-(5-d3-methyl-2-pyridinyl-κN2)phenyl-κC]iridium(III) (abbreviation: [Ir(5mppy-d3) ２ (mdppy-d3)]), [2-methyl-8-(2-pyridinyl-κN)benzofl[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(III) (abbreviation: Ir(ppy) ２ Organometallic iridium complexes having a pyridine skeleton such as (mdppy), bis(2,4-diphenyl-1,3-oxazolato-N,C) ２’ Iridium(III) acetylacetonate (abbreviation: Ir(dpo)) ２ (acac), bis{2-[4'-(perfluorophenyl)phenyl]pyridinate-N,C ２’ Iridium(III) acetylacetonate (abbreviation: Ir(p-PF-ph)) ２(acac), bis(2-phenylbenzothiazolat-N,C) ２’ Iridium(III) acetylacetonate (abbreviation: Ir(bt)) ２ In addition to organometallic iridium complexes such as (acac), there are also (2-{1-(5-tert-butylbiphenyl-2-yl)-4-[3-tert-butyl-5-(4-phenyl-2-pyridinyl-κN)phenyl-κC6]-2-benzimidazolyl-κN3}-4,6-di-tert-butylphenolate-κO)platinum(II) (abbreviation: Pt(tBudpppymmtBubiz-tBubp)), [2-(4-(3,5-di-tert- Organometallic platinum complexes such as butylphenyl)-6-{3-[4-(5'-tert-butyl[1,1':3',1''-terphenyl]-2'-yl)-2-pyridinyl-κN]phenyl-κC2}-2-pyridinyl-κN)phenolate-κO]platinum(II) (abbreviation: Pt(4tButpppypyp-mmtBup)), tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: [Tb(acac) ３ Examples include rare earth metal complexes such as (Phen)). These are compounds that mainly exhibit green phosphorescence and have emission peaks in the wavelength range of 500 nm to 600 nm. Organometallic iridium complexes with a pyrimidine skeleton are particularly preferred due to their outstanding reliability and luminescence efficiency. Compounds in which some of the hydrogen atoms are replaced with deuterium can also be used.

[0162] Also, (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(III) (abbreviation: [Ir(5mdppm) ２ (dibm)]), bis[4,6-bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(5mdppm) ２ (dpm)]), bis[4,6-di(naphthalene-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(d1npm) ２Organometallic iridium complexes having a pyrimidine skeleton such as (dpm)]), (acetylacetonato)bis(2,3,5-triphenylpyradinato)iridium(III) (abbreviation: [Ir(tppr) ２ (acac)), bis(2,3,5-triphenylpyrazinato)(dipivaloylmethanato) iridium(III) (abbreviation: [Ir(tppr) ２ (dpm)]), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq) ２ Organometallic iridium complexes having a pyrazine skeleton such as (acac), tris(1-phenylisoquinolinato-N,C) ２’ Iridium (III) (abbreviation: [Ir(piq) ３ ]), bis(1-phenylisoquinolinato-N,C ２’ Iridium (III) acetylacetonate (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 In addition to organometallic iridium complexes with a pyridine skeleton such as [-κC]iridium(III), there are 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-tenoyl)-3,3,3-trifluoroacetonate](monophenanthroline) europium(III) (abbreviation: [Eu(TTA) ３Examples include rare earth metal complexes such as (Phen)). These exhibit emission peaks in the wavelength range of 600 nm to 700 nm. Furthermore, organometallic iridium complexes with a pyrazine skeleton yield red emission with good chromaticity. Other known substances that exhibit red phosphorescence can also be used. Compounds in which some of the hydrogen atoms in these compounds are replaced with deuterium can also be used.

[0163] Furthermore, if the same light-emitting device contains light-emitting devices with different configurations, the light-emitting material may be a fluorescent material, a phosphorescent material, a material that exhibits thermally activated delayed fluorescence (TADF), or any other light-emitting material.

[0164] Next, we will describe a preferred configuration for the light-emitting layer 113 in which a fluorescent compound is used as the guest material 119, and in which the TADF mechanism is likely to occur.

[0165] TADF is S １ Level and T １ In systems with a very small energy difference between levels, a small amount of thermal energy can cause a reverse intersystem crossing from triplet excitation energy to singlet excitation energy, and fluorescence emission is generated from the converted singlet excitation energy. Therefore, it is possible to upconvert (reverse intersystem crossing) triplet excitation energy to singlet excitation energy, and singlet excited states can be efficiently generated. Furthermore, triplet excitation energy can be converted into luminescence. Materials exhibiting the TADF mechanism are sometimes called TADF materials.

[0166] The TADF mechanism may manifest with only one substance or with two substances. Note that the excited complex (also called an exciplex) formed by two substances is S １ Level and T １ It has an extremely small energy difference with the energy level and functions as a TADF material capable of converting triplet excitation energy into singlet excitation energy.

[0167] Note, - １The level indicator can be calculated using the emission edge of the phosphorescence spectrum observed at low temperatures (for example, any temperature in the range of 4K to 80K). １ As an indicator of the energy level, the emission edge of the PL spectrum measured at low temperature (e.g., any temperature in the range of 4K to 80K) or at room temperature can be used. Furthermore, the S of the fluorescent material... １ As an indicator of the energy level, an absorption spectrum measured at room temperature can also be used. For example, if an absorption spectrum is measured at room temperature, the energy at the absorption edge on the longer wavelength side can be defined as S. １ It can also be considered as an energy level. The absorption edge on the long-wavelength side of the absorption spectrum can be calculated by drawing a tangent line at the point where the slope on the long-wavelength side of the peak (or shoulder peak) observed at the longest wavelength of the absorption spectrum is minimum (maximum absolute value), and then taking the intersection of that tangent line with the horizontal axis (wavelength) or baseline. １ Level and T １ For comparing energy levels, it is particularly preferable to compare the emission edge of the fluorescence spectrum with the emission edge of the phosphorescence spectrum. １ Level and T １ The energy difference between the levels is preferably 0.3 eV or less, and more preferably 0.2 eV or less.

[0168] Furthermore, when using TADF material as a light-emitting material, the S of the host material １ The level is S of the TADF material. １ A higher level is preferable. Also, the T of the host material １ The level is T of the TADF material. １ A level higher than the current level is preferable.

[0169] As TADF materials, fullerenes and their derivatives, acridines and their derivatives, eosin derivatives, etc. can be used. Also, metal-containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (Pd) can be used. As a metal-containing porphyrin, for example, the protoporphyrin-tin fluoride complex (SnF) shown in the following structural formula is used. ２ (Proto IX)), Mesoporphyrin-Tin Fluoride Complex (SnF２ (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)), Ethioporphyrin-Tin Fluoride Complex (SnF ２ (Etio I)), Octaethylporphyrin-Platinum Chloride Complex (PtCl ２ OEP (Open Economic Programme) is another example.

[0170]

[0171] Furthermore, the following structural formulas represent 2-(biphenyl-4-yl)-4,6-bis(12-phenylindoro[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), 9-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9'-phenyl-3,3'-bi-9H-carbazole (abbreviation: PCCzPTZn), and 2-[4-(10H-phenoxazine-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PXZ). Heterocyclic compounds having one or both of a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring can also be used, such as -TRZ), 3-[4-(5-phenyl-5,10-dihydrophenadin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviated as PPZ-3TPT), 3-(9,9-dimethyl-9H-acridine-10-yl)-9H-xanthene-9-one (abbreviated as ACRXTN), bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviated as DMAC-DPS), and 10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracene]-10'-one (abbreviated as ACRSA). The heterocyclic compound is preferred because it has both a π-electron-excess heteroaromatic ring and a π-electron-deficient heteroaromatic ring, resulting in high electron transport and hole transport properties. Among the skeletons having a π-electron-deficient heteroaromatic ring, the pyridine skeleton, diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), and triazine skeleton are preferred because they are stable and reliable. In particular, the benzoflopyrimidine skeleton, benzothienopyrimidine skeleton, benzoflopyrazine skeleton, and benzothienopyrazine skeleton are preferred because they have high acceptability and are reliable. Furthermore, among the skeletons having a π-electron-excess heteroaromatic ring, the acridine skeleton, phenoxazine skeleton, phenothiazine skeleton, furan skeleton, thiophene skeleton, and pyrrole skeleton are preferred because they are stable and reliable, and therefore it is preferable to have at least one of these skeletons. Dibenzofuran skeleton is preferred as the furan skeleton, and dibenzothiophene skeleton is preferred as the thiophene skeleton.Furthermore, as pyrrole skeletons, indole skeletons, carbazole skeletons, indrocarbazole skeletons, bicarbazole skeletons, and 3-(9-phenyl-9H-carbazole-3-yl)-9H-carbazole skeletons are particularly preferred. In addition, in substances in which a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring are directly bonded, both the electron-donating ability of the π-electron-rich heteroaromatic ring and the electron-accepting ability of the π-electron-deficient heteroaromatic ring are strengthened. １ Level and T １ This is particularly preferable because the energy difference between the energy levels becomes small, allowing for efficient acquisition of thermally activated delayed fluorescence. Alternatively, an aromatic ring to which an electron-withdrawing group such as a cyano group is attached may be used instead of the π-electron-deficient heteroaromatic ring. Furthermore, aromatic amine skeletons, phenazine skeletons, etc., can be used as the π-electron-rich skeleton. Additionally, boron-containing skeletons such as xanthene skeletons, thioxanthene dioxide skeletons, oxadiazole skeletons, triazole skeletons, imidazole skeletons, anthraquinone skeletons, boron-containing skeletons such as phenylborane or volanthrene, aromatic rings or heteroaromatic rings having a nitrile group or a cyano group such as benzonitrile or cyanobenzene, carbonyl skeletons such as benzophenone, phosphine oxide skeletons, sulfone skeletons, etc. Thus, a π-electron-deficient skeleton and a π-electron-rich skeleton can be used instead of at least one of the π-electron-deficient heteroaromatic ring and the π-electron-rich heteroaromatic ring.

[0172]

[0173] Furthermore, a TADF material may be used that enables extremely fast and reversible intersystem crossing, and in which the singlet and triplet excited states emit light according to a thermal equilibrium model. Such a TADF material has an extremely short emission lifetime (excitation lifetime) as a TADF material, and can suppress the decrease in efficiency in the high-brightness region of the light-emitting element. Specifically, materials with the molecular structure shown below can be used.

[0174]

[0175] Next, we will describe a preferred configuration for the light-emitting layer 113 in which a fluorescent compound is used as the guest material 119, and the TTA mechanism is generated.

[0176] In the case of a light-emitting device that uses a fluorescent material in the light-emitting layer and utilizes the TTA mechanism to increase luminescence efficiency, the lowest singlet energy level (S) of the host material is important. １ The level is the S of the fluorescent material. １ Higher than the level, and the lowest triplet energy level of the host material (T １ The T level of a fluorescent material is １ It is preferable that the luminescence level is lower than the host level. Furthermore, it is more preferable that the energy difference between the HOMO level of the host material and the HOMO level of the fluorescent material is 0.25 eV or more. In addition, it is preferable that the concentration of the fluorescent material in the luminescence layer is 0.5% by weight or more and 25% by weight or less relative to the host material. With this configuration, holes are more easily trapped in the luminescence layer, and carriers recombine locally in the region on the hole transport layer side of the luminescence layer, increasing the exciton density and thus improving the efficiency of TTA. Another configuration that enhances luminescence efficiency using TTA is that it is more preferable that the LUMO level of the fluorescent material is lower than the LUMO level of the host material. With this configuration, electrons are more easily trapped in the luminescence layer, and carriers recombine locally in the region on the hole transport layer side of the luminescence layer, increasing the exciton density and thus improving the efficiency of TTA.

[0177] The HOMO and LUMO levels used in this specification can be determined by electrochemical measurements. Typical examples of electrochemical measurements include cyclic voltammetry (CV) and differential pulse voltammetry (DPV).

[0178] In cyclic voltammetry (CV) measurements, the values ​​of the HOMO and LUMO levels (E) are obtained by changing the oxidation peak potential (E) relative to the reference electrode. ｐａ ), and reduction peak potential (E ｐｃ It can be calculated based on the following. In the measurement, the HOMO level is determined from the positive potential scan and the LUMO level is determined from the negative potential scan. The scan speed in the measurement is set to 0.1 V / s.

[0179] The specific procedures for calculating the HOMO and LUMO levels are described below. The oxidation peak potential (E) is obtained from the cyclic voltammogram of the material. ｐａ ), and reduction peak potential (E ｐｃ ) From the standard oxidation-reduction potential (E ｏ ) (=(E ｐａ +E ｐｃ ) / 2) is calculated, and the potential energy (E) of the reference electrode with respect to the vacuum level is calculated. ｘ By subtracting from ), the values ​​(E) (= Ex - Eo) of the HOMO level and the LUMO level can be determined, respectively.

[0180] Note that the above shows the case where a reversible redox wave is obtained, but when an irreversible redox wave is obtained, the oxidation peak potential (E) is used to calculate the HOMO level. ｐａ The reduced peak potential (E) is obtained by subtracting a certain value (0.1 eV) from the value obtained by subtracting a certain value (0.1 eV) from the value obtained by subtracting a certain value (0.1 eV) from the value obtained by subtracting a certain value (E ｐｃ ) Assuming the standard oxidation-reduction potential (E ｏ ) is calculated to one decimal place. Also, the reduction peak potential (E) is used to calculate the LUMO level. ｐｃ The oxidation peak potential (E) is calculated by adding a constant value (0.1 eV) to the value obtained). ｐａ ) Assuming the standard oxidation-reduction potential (E ｏ Calculate the result to one decimal place.

[0181] Note S １ Levels and T １ The energy levels can be determined by using values ​​calculated from the emission edge of the phosphorescence or fluorescence spectrum and the absorption edge of the absorption spectrum, as described above.

[0182] Examples of materials that can be used as fluorescent light-emitting substances in the light-emitting layer 113 include the following. Other fluorescent light-emitting substances can also be used.

[0183] 5,6-bis[4-(10-phenyl-9-antryl)phenyl]-2,2'-bipyridine (abbreviation: PAPP2BPy), 5,6-bis[4'-(10-phenyl-9-antryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyren-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-carbazole-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazole-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazole-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAAPPA), N,9-diphenyl-N-[4-( 10-phenyl-9-anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra-tert-butylperylene (abbreviation: TBP), 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBAPA), N,N''-(2-tert-butylanthracene-9,10-diyldi-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-carbazole-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-carbazole-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazole-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-carbazole-9-yl)phenyl]-N-phenylanthracene-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracene-9-amine (abbreviation: DPhAPhA), coumarin 545T, N,N'-diphenylquinacridone (abbreviation: DPQd), rubren, 5,12-bis(biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyra N-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-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]fluorantene-3,10-diamine (abbreviation) Name: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-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]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]ethenyl}-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]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), N,N'-diphenyl-N,N'-(1,6-pyrene-diyl)bis[(6-phenylbenzo[b]naph Examples include to[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03), N,N'-diphenyl-N,N'-bis(9-phenyl-9H-carbazole-2-yl)naphtho[2,3-b;6,7-b']bisbenzofuran-3,10-diamine (abbreviation: 3,10PCA2Nbf(IV)-02), and 3,10-bis[N-(dibenzofuran-3-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10FrA2Nbf(IV)-02). In particular, condensed aromatic diamine compounds, such as pyrenediamine compounds like 1,6FLPAPrn, 1,6mMemFLPAPrn, and 1,6BnfAPPrn-03, are preferred because they exhibit high hole-trapping properties and excellent luminescence efficiency or reliability.

[0184] Also, 2,12-di(tert-butyl)-5,9-di(4-tert-butylphenyl)-N,N-diphenyl-5H,9H-[1,4]benzazabolino[2,3,4-kl]phenazabolin-7-amine (abbreviation: DPhA-tBu4DABNA), 2,12-di(tert-butyl)-N,N,5,9-tetra(4-tert-butylphenyl)-5H,9H-[1,4]benzazabolino[2,3,4-kl]phenazabolin-7-amine (abbreviation: tBuDPhA-tBu4DABNA), 2,12-di(tert-butyl)-5,9-di(4-ter Materials having a diazabora-naphthanthracene skeleton, such as t-butylphenyl)-7-methyl-5H,9H-[1,4]benzazaborino[2,3,4-kl]phenazavolin (abbreviation: Me-tBu4DABNA) and N7,N7,N13,N13,5,9,11,15-octaphenyl-5H,9H,11H,15H-[1,4]benzazaborino[2,3,4-kl][1,4]benzazaborino[4',3',2':4,5][1,4]benzazaborino[3,2-b]phenazavolin-7,13-diamine (abbreviation: ν-DABNA), can be used.

[0185] In addition to these, 9,10,11-tris[3,6-bis(1,1-dimethylethyl)-9H-carbazole-9-yl]-2,5,15,18-tetrakis(1,1-dimethylethyl)indoro[3,2,1-de]indoro[3',2',1':8,1][1,4]benzazaborino[2,3,4-kl]phenazavolin (abbreviation: BBCz-G), 9,11-bis[ Compounds having an indole skeleton, such as 3,6-bis(1,1-dimethylethyl)-9H-carbazole-9-yl]-2,5,15,18-tetrakis(1,1-dimethylethyl)indoro[3,2,1-de]indoro[3',2',1':8,1][1,4]benzazavolino[2,3,4-kl]phenazavolin (abbreviation: BBCz-Y), can be suitably used.

[0186] Examples of electron transport materials used as the host material for the light-emitting layer 113 include bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviated as BeBq). ２Metal complexes such as bis(2-methyl-8-quinolinolato)(4-phenylphenololato)aluminum(III) (abbreviated as BAlq), bis(8-quinolinolato)zinc(II) (abbreviated as Znq), bis[2-(2-benzoxazollyl)phenololato]zinc(II) (abbreviated as ZnPBO), and bis[2-(2-benzothiazolyl)phenololato]zinc(II) (abbreviated as ZnBTZ), as well as organic compounds having a π-electron-deficient heteroaromatic ring, can be used. Examples of organic compounds having a π-electron-deficient heteroaromatic ring include 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated as PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviated as TAZ), and 1,3-bis[5-(4-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviated as Azole skeletons such as OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazole-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), and 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II) Organic compounds containing heteroaromatic rings, such as 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPBQ-II), and 2-[3'-(9H-carbazole-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2m CzBPDBq), 4,6-bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 2,4-bis[4-(1-naphthyl)phenyl]-6-[4-(3-pyridyl)phenyl]pyrimidine (abbreviation: 2,4NP-6PyPPm), 6-(biphenyl-3-yl)-4-[3,Organic compounds containing heteroaromatic rings with a diazine skeleton, such as 5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenyl-6-(biphenyl-4-yl)pyrimidine (abbreviation: 6BP-4Cz2PPm), and 7-[4-(9-phenyl-9H-carbazole-2-yl)quinazoline-2-yl]-7H-dibenzo[c,g]carbazole (abbreviation: PC-cgDBCzQz), and 3,5-bis[3-(9H-carbazole Organic compounds containing heteroaromatic rings with a pyridine skeleton, such as 2-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[(3-pyridyl)phenyl-3-yl]benzene (abbreviation: TmPyPB), 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFBPTZn), and 2-(biphenyl-4-yl)-4-phenyl-6-(9,9'-spirobio[9H-fluoren]-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), 5-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]carbazole (abbreviation: mINc(I I) PTZn), 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-triazine-2-yl)-2-dibenzofuranyl]-9-phenyl-9H-carbazole (abbreviation: PCDBfTZn), 2-(biphenyl-3-yl)-4-phenyl-6-[8-([1,1':4',1''-terphenyl]-4-yl)-1-dibenzofuranyl]-1,3,5-triazine (abbreviation: mBP-TPDBfTZn), 9,Examples include organic compounds containing heteroaromatic rings having a triazine skeleton, such as 9'-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole) (abbreviated as SiTrzCz2) and 2-phenyl-4,6-bis[3-(triphenylsilyl)phenyl]-1,3,5-triazine (abbreviated as mSiTrz), and organic compounds containing heteroaromatic rings having boron, such as 4-(2,12-di-tert-butyl-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene-7-yl)phenyl]triphenylsilane. Among the above, organic compounds containing heteroaromatic rings having a diazine skeleton, organic compounds containing heteroaromatic rings having a pyridine skeleton, and organic compounds containing heteroaromatic rings having a triazine skeleton are preferred due to their good reliability. In particular, organic compounds containing heteroaromatic rings having a diazine (pyrimidine and pyrazine) skeleton, and organic compounds containing heteroaromatic rings having a triazine skeleton, exhibit high electron transport properties and contribute to reducing the driving voltage. Furthermore, the organic compounds of Embodiment 1 can be used as electron transport materials for the host material.

[0187] As the hole transport material used in the host material of the light-emitting layer 113, an organic compound having an amine skeleton or a π-electron-rich heteroaromatic ring can also be used. Examples of such organic compounds having an amine skeleton or a π-electron-rich heteroaromatic ring include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviated as TPD), N,N'-bis(9,9'-spirobi[9H-fluorene]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviated as BSPB), and 4-phenyl-4'-(9-phenylfluorene (9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazole-3 -yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBNBB), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9'-spirovi[9H-fluoren]-2-amine ( Compounds having an aromatic amine skeleton such as PCBASF, 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 9,9'-diphenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCCP), 3,3'-9H-carbazole-9-yl-biphenyl (abbreviation: mCBP), 9'-phenyl-9'H-9,3':6',Compounds having a carbazole skeleton such as 9''-tercarbazole (abbreviation: PhCzGI), 9-[3-(triphenylsilyl)phenyl]-3,9'-bi-9H-carbazole (abbreviation: PSiCzCz), 12-[3-(9H-carbazole-9-yl)phenyl]-5,12-dihydro-5-phenyl-indoro[3,2-a]carbazole (abbreviation: mCzPICz), 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluorene] Examples include compounds having a thiophene skeleton such as -9-yl)phenyl]dibenzothiophene (abbreviated as DBTFLP-III) and 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviated as DBTFLP-IV), and compounds having a furan skeleton such as 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviated as DBF3P-II) and 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviated as mmDBFFLBi-II). Among the above, compounds having an aromatic amine skeleton or a carbazole skeleton are preferred because they have good reliability, high hole transportability, and contribute to reducing the driving voltage. Furthermore, organic compounds listed as examples of hole transportable materials in the hole transport layer 112 can also be used as hole transport materials for the host.

[0188] Furthermore, by mixing electron transport material and hole transport material, the transport properties of the light-emitting layer 113 can be easily adjusted, and the recombination region can be easily controlled.

[0189] Furthermore, TADF materials can also be used as electron transport materials or hole transport materials. The TADF materials listed above can be used as host materials in the same way. When a TADF material is used as a host material, the triplet excitation energy generated by the TADF material is converted to singlet excitation energy through reverse intersystem crossing, and this energy is then transferred to the light-emitting material, thereby increasing the luminescence efficiency of the light-emitting device. In this case, the TADF material functions as an energy donor, and the light-emitting material functions as an energy acceptor.

[0190] This is very effective when the above-mentioned luminescent material is a fluorescent luminescent material. Also, in order to obtain high luminescence efficiency in this case, the S of the TADF material １ The energy level is S of the fluorescent material. １ It is preferable that the level be higher than the level. Also, the T of the TADF material １ The energy level is preferably higher than the S1 level of the fluorescent material. Therefore, the T of the TADF material is １ The energy level is the T of the fluorescent material. １ A level higher than the current level is preferable.

[0191] Furthermore, it is preferable to use a TADF material that exhibits emission that overlaps with the wavelength of the lowest-energy absorption band of the fluorescent material. This is preferable because it allows for a smooth transfer of excitation energy from the TADF material to the fluorescent material, resulting in efficient emission.

[0192] Furthermore, for singlet excitation energy to be efficiently generated from triplet excitation energy by reverse intersystem crossing, it is preferable that carrier recombination occurs in the TADF material. It is also preferable that the triplet excitation energy generated in the TADF material does not transfer to the triplet excitation energy of the fluorescent material. To achieve this, it is preferable that the fluorescent material has protecting groups around the luminescent phosphoform (the skeleton that causes luminescence). Preferred protecting groups are substituents without π bonds, and saturated hydrocarbons are preferred. Specifically, examples include alkyl groups having 3 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 10 carbon atoms, and trialkylsilyl groups having 3 to 10 carbon atoms. It is even more preferable to have multiple protecting groups. Substituents without π bonds have poor carrier transport function, and therefore can increase the distance between the TADF material and the luminescent phosphoform of the fluorescent material with little effect on carrier transport and carrier recombination. Here, the luminescent phosphoform refers to the atomic group (skeleton) that causes luminescence in the fluorescent material. The luminescent phosphophore preferably has a skeleton containing π bonds, preferably contains an aromatic ring, and preferably has a condensed aromatic ring or a condensed heteroaromatic ring. Examples of such luminescent phosphophores include phenanthrene skeletons, stilbene skeletons, acridone skeletons, phenoxazine skeletons, phenothiazine skeletons, naphthalene skeletons, anthracene skeletons, fluorene skeletons, chrysene skeletons, triphenylene skeletons, tetracene skeletons, pyrene skeletons, perylene skeletons, coumarin skeletons, quinacridone skeletons, and naphthobisbenzofuran skeletons. Fluorescent materials having naphthalene, anthracene, fluorene, chrysene, triphenylene, tetracene, pyrene, perylene, coumarin, quinacridone, and naphthobisbenzofuran skeletons are particularly preferred due to their high fluorescence quantum yield.

[0193] Furthermore, when a fluorescent material is used as the light-emitting material in the light-emitting layer 113, it is more preferable to use a condensed polycyclic aromatic compound such as anthracene derivatives, tetracene derivatives, phenanthrene derivatives, pyrene derivatives, chrysene derivatives, or dibenzo[g,p]chrysene derivatives as the host material, which is an organic compound with a high energy level in the singlet excited state and a low energy level in the triplet excited state. Materials having an anthracene skeleton are particularly preferred. When a substance having an anthracene skeleton is used as the host material for the fluorescent material, it is possible to realize a light-emitting layer with good luminescence efficiency and durability. Among the substances having an anthracene skeleton to be used as the host material, substances having a diphenylanthracene skeleton, and especially a 9,10-diphenylanthracene skeleton, are preferred because they are chemically stable.Examples of such substances include 9-phenyl-3-[4-(10-phenyl-9-antryl)phenyl]-9H-carbazole (abbreviated as PCzPA), 3-[4-(1-naphthyl)phenyl]-9-phenyl-9H-carbazole (abbreviated as PCPN), 9-[4-(10-phenyl-9-antryl)phenyl]-9H-carbazole (abbreviated as CzPA), and 7-[4-(10-phenyl-9-antryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviated as cg DBCzPA), 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-(2-naphthyl)anthracene (abbreviation: α,βADN), 2-(10-phenylanthracene-9-yl)dibenzofuran, 2-(10-phenyl Lu-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), 9-(1-naphthyl)-10-[4-(2-naphthyl)phenyl]anthracene (abbreviation: αN-βN Examples include PANth), 2,9-di(1-naphthyl)-10-phenylanthracene (abbreviation: 2αN-αNPhA), 1-[10-(phenyl-2,3,4,5,6-d5)-9-anthryl]benzo[b]naphtho[2,3-d]furan (abbreviation: Bnf(II)PhA-02-d5), and 7-(phenyl-2,3,4,5,6-d5)-1-[10-(phenyl-2,3,4,5,6-d5)-9-anthryl]dibenzofuran (abbreviation: PDBfPhA-d10).

[0194] Furthermore, phosphorescent materials can be used as part of the above-mentioned mixed materials. When a fluorescent material is used as the light-emitting material, the phosphorescent material can be used as an energy donor to supply excitation energy to the fluorescent material.

[0195] Furthermore, an excitation complex may be formed between the mixed materials described above. It is preferable to select a combination of materials that forms an excitation complex that exhibits emission overlapping with the wavelength of the lowest-energy absorption band of the luminescent material, as this facilitates smooth energy transfer and efficiently obtains light emission. This configuration is also preferable because it reduces the driving voltage.

[0196] Furthermore, at least one of the materials forming the excitation complex may be a phosphorescent material. By doing so, the triplet excitation energy can be efficiently converted to singlet excitation energy through reverse intersystem crossing.

[0197] For efficient excitation complex formation, it is preferable that the HOMO level of the hole-transporting material is at or above the HOMO level of the electron-transporting material. Furthermore, it is preferable that the LUMO level of the hole-transporting material is at or above the LUMO level of the electron-transporting material.

[0198] The formation of excited complexes can be confirmed, for example, by comparing the emission spectra of a hole-transporting material, an electron-transporting material, and a mixed film made by mixing these materials, and observing that the emission spectrum of the mixed film shifts to a longer wavelength than the emission spectra of each individual material (or has a new peak on the longer wavelength side). Alternatively, it can be confirmed by comparing the transient photoluminescence (PL) of a hole-transporting material, the transient PL of an electron-transporting material, and the transient PL of a mixed film made by mixing these materials, and observing differences in the transient response, such as the transient PL lifetime of the mixed film having a longer lifetime component or a larger proportion of the delayed component than the transient PL lifetime of each individual material. Furthermore, the transient PL mentioned above may be read as transient electroluminescence (EL). That is, the formation of excited complexes can also be confirmed by comparing the transient EL of a hole-transporting material, the transient EL of an electron-transporting material, and the transient EL of a mixed film made by mixing these materials, and observing the differences in the transient response.

[0199] The light-emitting layer 113 can be formed by methods other than the light-emitting mechanism, such as vapor deposition (including vacuum deposition), inkjet printing, coating, and gravure printing. In addition to the materials mentioned above, it may also contain inorganic compounds such as quantum dots or polymer compounds (oligomers, dendrimers, polymers, etc.).

[0200] ≪Hole Injection Layer≫ The hole injection layer (111, 111a, 111b) is a layer that injects holes from the first electrode 101, which is the anode, and the charge generation layer (106, 106a, 106b) into the organic compound layer (103, 103a, 103b), and is a layer that contains an organic acceptor material and a material with high hole injection potential.

[0201] The hole injection layers (111, 111a, 111b) can be compounds having electron-withdrawing groups (halogen groups or cyano groups), such as 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F ４Examples include HAT-CN, chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviated as HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviated as F6-TCNNQ), and 2-(7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyrene-2-ylidene)malononitrile. In particular, compounds in which an electron-withdrawing group is bonded to a condensed aromatic ring having multiple heteroatoms, such as HAT-CN, are thermally stable and therefore preferred. Furthermore, [3]radialene derivatives having electron-withdrawing groups (especially halogen groups such as fluoro groups or cyano groups) are preferred because they have very high electron-accepting properties. Specifically, examples include α,α',α''-1,2,3-cyclopropanetriylidenates (4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile) (abbreviated as Rad), α,α',α''-1,2,3-cyclopropanetriylidenates [2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], and α,α',α''-1,2,3-cyclopropanetriylidenates [2,3,4,5,6-pentafluorobenzeneacetonitrile]. In addition to the organic compounds mentioned above, molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, manganese oxide, etc. can be used as substances with acceptor properties. Other examples include phthalocyanine (abbreviated as H ２ Hole injection layers (111, 111a, 111b) can also be formed by phthalocyanine compounds such as Pc, phthalocyanine complex compounds such as copper phthalocyanine (CuPc), aromatic amine compounds such as 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviated as DPAB), N,N'-bis[4-bis(3-methylphenyl)aminophenyl]-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviated as DNTPD), or polymers such as poly(3,4-ethylenedioxythiophene) / polystyrene sulfonic acid (abbreviated as PEDOT / PSS). Accepting substances can extract electrons from adjacent hole transport layers (or hole transport materials) by applying an electric field.

[0202] Furthermore, among substances with acceptor properties, organic compounds with acceptor properties are easy to use because they are readily deposited and easy to form films.

[0203] Furthermore, a composite material containing the above-mentioned acceptor substance in a hole-transporting material can also be used as the hole injection layer (111, 111a, 111b). By using a composite material containing the acceptor substance in a hole-transporting material, it is possible to select the material for forming the electrode regardless of the work function. In other words, not only materials with a large work function but also materials with a small work function can be used as the anode (first electrode 101).

[0204] Various organic compounds can be used as hole-transporting materials in composite materials, including aromatic amine compounds, carbazole derivatives, aromatic hydrocarbons, and polymer compounds (oligomers, dendrimers, polymers, etc.). −６ cm ２ It is preferable that the material has a hole mobility of 1 / Vs or higher. Below, we specifically list organic compounds that can be used as hole transporting materials in composite materials.

[0205] Aromatic amine compounds that can be used in composite materials include N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviated as DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviated as DPAB), N,N'-bis[4-bis(3-methylphenyl)aminophenyl]-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviated as DNTPD), and 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviated as DPA3B). Specifically, carbazole derivatives include 3-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviated as PCzPCA1), 3,6-bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviated as PCzPCA2), and 3-[N-(1-naphthyl)-N-(9-phenylcarbazole-3-yl)amino]-9-phenyl Carbazole (abbreviated as PCzPCN1), 4,4'-di(N-carbazolyl)biphenyl (abbreviated as CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviated as TCPB), 9-[4-(10-phenyl-9-antryl)phenyl]-9H-carbazole (abbreviated as CzPA), 1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene, etc. can be used.Examples of aromatic hydrocarbons include 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAth), 2-tert-butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA), 2-tert- Examples include butyl-9,10-bis[2-(1-naphthyl)phenyl]anthracene, 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene, 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene, 9,9'-biantryl, 10,10'-diphenyl-9,9'-biantryl, 10,10'-bis(2-phenylphenyl)-9,9'-biantryl, 10,10'-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9'-biantryl, anthracene, tetracene, rubrene, perylene, and 2,5,8,11-tetra(tert-butyl)perylene. In addition, pentacene, coronene, and the like can also be used. Furthermore, it may have a vinyl skeleton. Examples of aromatic hydrocarbons having a vinyl group include 4,4'-bis(2,2-diphenylvinyl)biphenyl (abbreviated as DPVBi) and 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviated as DPVPA). Organic compounds according to one embodiment of the present invention can also be used.

[0206] In addition, polymer compounds such as poly(N-vinylcarbazole) (abbreviated as PVK), poly(4-vinyltriphenylamine) (abbreviated as PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviated as PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviated as Poly-TPD) can also be used.

[0207] The hole-transporting material used in the composite material more preferably has at least one of the following skeletons: carbazole, dibenzofuran, dibenzothiophene, and anthracene. In particular, it may be an aromatic amine having substituents including a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine having a naphthalene ring, or an aromatic monoamine in which a 9-fluorenyl group is bonded to the nitrogen of the amine via an arylene group. Furthermore, it is preferable that these organic compounds are substances having an N,N-bis(4-biphenyl)amino group, as this allows for the creation of light-emitting devices with a good lifetime. Specifically, the organic compounds described above include N-(4-biphenyl)-6,N-diphenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviated as BnfABP), N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviated as BBABnf), and 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-(dibenzothiophen-4-yl)phenyl]-N-phenyl-4-biphenylamine (abbreviation: ThBA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenylamine (abbreviation: BB AβNB), 4-[4-(2-naphthyl)phenyl]-4',4''-diphenyltriphenylamine (abbreviation: BBAβNBi), 4,4'-diphenyl-4''-([2,1'-binaphthyl]-6-yl)triphenylamine (abbreviation: BBAαNβNB), 4,4'-diphenyl-4''-([2,1'-binaphthyl]-7-yl)triphenylamine (abbreviation: BBAαNβNB-03), 4,4'-diphenyl-4''-(7-phenyl)naphthyl-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4,4'-diphenyl-4''-([2,2'-binaphthyl]-6-yl)triphenylamine (abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-([2,2'-binaphthyl]-7-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diphenyl-4''-([1,2'-binaphthyl]-4-yl)triphenylamine (abbreviation: BBAβNαNB), 4,4'-diphenyl-4''-( [1,2'-binaphthyl]-5-yl)triphenylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenylyl)-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB), 4-(3-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: mTPBiAβNBi), 4-(4-biphenylyl)-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'-(carbazole-9-yl)biphenyl-4-yl]triphenylamine (abbreviation: YGTBi1BP), 4'-[4-(3-phenyl-9H-carbazole-9-yl)phenyl]tris(biphenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carbazole-9-yl)biphenyl-4-yl]-4'-(2-naphthyl)-4''-phenyl Triphenylamine (abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9'-spirobio[9H-fluorene]-2-amine (abbreviation: PCBNBSF), N,N-bis(biphenyl-4-yl)-9,9'-spirobio[9H-fluorene]-2-amine (abbreviation: BBASF), N,N-bis(biphenyl-4-yl)-9,9'-spirobio[9H-fluorene]-4-amine (abbreviation: BBASF(4)), N-(biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi[9H-fluoren]-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-carbazole-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9 H-carbazole-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBNBB), N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF), N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H-fluorene-2-amine Examples include PCBiF (abbreviation: PCBiF), N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-4-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-3-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-2-amine, and N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-1-amine.

[0208] Furthermore, it is even more preferable that the hole-transporting material used in the composite material has a relatively low HOMO level between -5.7 eV and -5.4 eV. Having a relatively low HOMO level in the hole-transporting material used in the composite material facilitates the injection of holes into the hole transport layer 112 and makes it easier to obtain a light-emitting device with a good lifetime. In addition, having a relatively low HOMO level in the hole-transporting material used in the composite material moderately suppresses hole induction, resulting in a light-emitting device with an even better lifetime.

[0209] Furthermore, by mixing alkali metal or alkaline earth metal fluoride into the above composite material (preferably with an atomic ratio of fluorine atoms of 20% or more in the layer), the refractive index of the layer can be reduced. This also makes it possible to form a layer with a low refractive index inside the EL layer 103, thereby improving the external quantum efficiency of the light-emitting device.

[0210] By forming hole injection layers (111, 111a, 111b), hole injection performance is improved, and a light-emitting device with a low driving voltage can be obtained.

[0211] ≪Hole Transport Layer≫ The hole transport layer (112, 112a, 112b) is a layer containing a hole transport material, and the hole transport material exemplified as the material for the hole injection layer (111, 111a, 111b) can be used. Since the hole transport layer (112, 112a, 112b) has the function of transporting holes injected into the hole injection layer (111, 111a, 111b) to the light-emitting layer (113, 113a, 113b), it is preferable that it has the same or close HOMO level as the HOMO level of the hole injection layer (111, 111a, 111b).

[0212] Also, 1 x 10 −６ cm ２ It is preferable that the material has a hole mobility of 1 / Vs or higher. However, other materials may be used as long as they have higher hole transport capabilities than electron transport capabilities. The layer containing the material with high hole transport capabilities may be a single layer, or two or more layers made of the above material may be stacked.

[0213] Materials that can be used for the hole transport layers (112, 112a, 112b) include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviated as TPD), N,N'-bis(9,9'-spirobi[9H-fluoren]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviated as BSPB), and 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviated as BPAFLP). , 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl Compounds having an aromatic amine skeleton such as 9H-carbazole-3-yl)triphenylamine (abbreviation: PCBNBB), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9'-spirobi[9H-fluoren]-2-amine (abbreviation: PCBASF), 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-di(N-carbazolyl) Biphenyl (abbreviated as CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviated as CzTP), 9,9'-diphenyl-9H,9'H-3,3'-bicarbazole (abbreviated as PCCP), 9,9'-bis(biphenyl-4-yl)-3,3'-bi-9H-carbazole (abbreviated as BisBPCz), 9,9'-bis(biphenyl-3-yl)-3,3'-bi-9H-carbazole (abbreviated as BismBPCz) (abbreviated as BismBPCz), 9-(biphenyl-3-yl)-9'-(biphenyl-4-yl)-9H,9'H-3,Compounds having a carbazole skeleton such as 3'-bicarbazole (abbreviation: mBPCCP), 4,4',4''-(benzene-1,3,5-triyl)tri(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) Examples include compounds having a thiophene skeleton such as phenyl]-6-phenyldibenzothiophene (abbreviated as DBTFLP-IV), and compounds having a furan skeleton such as 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviated as DBF3P-II) and 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviated as mmDBFFLBi-II). Among the above, compounds having an aromatic amine skeleton or a carbazole skeleton are preferred because they have good reliability, high hole transportability, and contribute to reducing the driving voltage. Furthermore, the materials listed as having hole transportability used in the composite material of the hole injection layer 111 can also be suitably used as materials constituting the hole transport layer 112.

[0214] ≪Electron Transport Layer≫ The electron transport layers (114, 114a, 114b) have the function of transporting electrons injected from the other electrode of the pair (first electrode 101 or second electrode 102) via the electron injection layers (115, 115a, 115b) to the light-emitting layer 113. Note that the electron transport layer may also use the organic compound described in Embodiment 1.

[0215] Furthermore, as an electron-transporting material, it is an organic compound having electron-transporting properties, and the electron mobility at which the square root of the electric field strength [V / cm] is 600 is 1 × 10⁻⁶. −６ cm ２A substance having an electron mobility of 1 / Vs or higher is preferred. However, any substance that has higher electron transport than holes can be used. As the above organic compound, an organic compound having a π-electron-deficient heteroaromatic ring is preferred. As an organic compound having a π-electron-deficient heteroaromatic ring, it is preferable that it be any or more of the following: an organic compound containing a heteroaromatic ring having an azole 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.

[0216] Organic compounds having a π-electron-deficient heteroaromatic ring that can be used in the above electron transport layer include, specifically, 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated as PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviated as TAZ), 1,3-bis[5-(4-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviated as OXD-7), and 9-[4-(5-phenyl-1,3,4-oxadiazole-2-yl]benzene. Organic compounds having an azole skeleton, such as sadiazole-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), 4,4'-bis(5-methylbenzoxazole-2-yl)stilbene (abbreviation: BzOs), and 3,5-bis[3-(9H-carbazole-9-yl)phenyl Organic compounds containing heteroaromatic rings with a pyridine skeleton, such as [nyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[(3-pyridyl)phenyl-3-yl]benzene (abbreviation: TmPyPB), vasophenanthroline (abbreviation: Bphen), vasocuproin (abbreviation: BCP), 2,9-di(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBphen), 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3 '-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carbazole-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mCzBPDBq), 2-[4'-(9-phenyl-9H-carbazole-3-yl)-3,1'-biphenyl-1-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mpPCBPDBq), 2-[4-(3,6-diphenyl-9H-carbazole-9-yl)phenyl]dibenzo[f,[h]Quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]Quinoxaline (abbreviation: 7mDBTPDBq-II), 6-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]Quinoxaline (abbreviation: 6mDBTPDBq-II), 9-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9mDBtBPNfpr), 9-[3'-(dibenzothiophen-4-yl)biphenyl -4-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9pmDBtBPNfpr), 4,6-bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6-bis[3-(9H-carbazole-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm), 9,9'-[pyrimidine-4,6-diylbis(biphenyl-3,3'-diyl)]bis(9 H-carbazole) (abbreviation: 4,6mCzBP2Pm), 8-(biphenyl-4-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzoflo[3,2-d]pyrimidine (abbreviation: 8BP-4mDBtPBfpm), 3,8-bis[3-(dibenzothiophen-4-yl)phenyl]benzoflo[2,3-b]pyrazine (abbreviation: 3,8mDBtP2Bfpr), 8-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]flo[3,2-d]pyrimidine (abbreviation: 8mDBtBPNfp m), 8-([2,2'-binaphthalene]-6-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofl[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-(2-naphthyl)phenyl]-6-phenylpyrimidine} (abbreviation: 2,6(NP-PPm)2Py), 6-(biphenyl-3-yl)-4-[3,5-Bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), 2,4-Bis[4-(1-naphthyl)phenyl]-6-[4-(3-pyridyl)phenyl]pyrimidine (abbreviation: 2,4NP-6PyPPm), 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenyl-6-(biphenyl-4-yl)pyrimidine (abbreviation: 6BP-4Cz2PPm), 7-[4-(9-phenyl-9H-carbazole-2-yl)quinazoline-2-yl]-7H-dibenzo[c,g]cal Organic compounds having a diazine skeleton, such as Bazole (abbreviation: PC-cgDBCzQz), 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFBPTZn), 2-(biphenyl-4-yl)-4-phenyl-6-(9,9'-spirobio[9H-fluoren]-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), 9-[4-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-9'-phenyl-3,3'-bi-9H-carbazole (abbreviation: PCCzPTZn), 9-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTZn-02), 5-[3-(4,6-diphenyl-1,3,5-triazine-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'-(pyridine-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviation: TmPPPyTz), 2-[3-(2,6-dimethyl-3-pyridinyl)-5-(9-phenanthryl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mPn-mDMePyPTZn), 11-[4-(biphenyl-4-yl)-6-phenyl-1,3,5-triazine-2-yl]-11,12-dihydro-12-phenylindoro[2,3-a]carbazole (abbreviation: BP-Icz(II)TZn), 2-[3'-(triphenylene-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3 Examples of organic compounds having a triazine skeleton include 5-triazine (abbreviated as mTpBPTZn), 3-[9-(4,6-diphenyl-1,3,5-triazine-2-yl)-2-dibenzofuranyl]-9-phenyl-9H-carbazole (abbreviated as PCDBfTZn), and 2-(biphenyl-3-yl)-4-phenyl-6-{8-[(1,1':4',1''-terphenyl)-4-yl]-1-dibenzofuranyl}-1,3,5-triazine (abbreviated as mBP-TPDBfTZn). Among the above, 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 are preferred due to their good reliability. In particular, organic compounds containing heteroaromatic rings with a diazine (pyrimidine and pyrazine) skeleton, and organic compounds containing heteroaromatic rings with a triazine skeleton, exhibit high electron transport properties and contribute to reducing the driving voltage.

[0217] Furthermore, the electron transport layers (114, 114a, 114b) may be not only a single layer, but also two or more layers made of the above material stacked together.

[0218] Furthermore, a layer for controlling the movement of electron carriers may be provided between the electron transport layers (114, 114a, 114b) and the light-emitting layers (113, 113a, 113b). This layer is made by adding a small amount of a substance with high electron-trapping properties to the electron-transporting material described above, and it is possible to adjust the carrier balance by suppressing the movement of electron carriers. Such a configuration is highly effective in suppressing problems that occur when electrons penetrate the light-emitting layer (for example, a decrease in device lifespan).

[0219] ≪Electron Injection Layer≫ The electron injection layers (115, 115a, 115b) have the function of promoting electron injection by reducing the electron injection barrier from the second electrode 102. Note that the organic compound described in Embodiment 1 can also be used as the electron injection layer.

[0220] Furthermore, for example, Group 1 metals, Group 2 metals, or their oxides, halides, carbonates, etc., can be used. Also, composite materials of the electron-transporting material and an electron-donating material can be used. Examples of electron-donating materials include Group 1 metals, Group 2 metals, or their oxides. Specifically, lithium fluoride (LiF), sodium fluoride (NaF), cesium fluoride (CsF), calcium fluoride (CaF) ２ ), lithium oxide (LiO ｘ Alkali metals, alkaline earth metals, or compounds thereof, such as ) can be used. Also, erbium fluoride (ErF) can be used. ３ Rare earth metal compounds such as ) can be used. Alternatively, an electride may be used in the electron injection layer 115. Examples of such electrides include a substance obtained by adding electrons to a mixed oxide of calcium and aluminum at a high concentration. Furthermore, the electron injection layers (115, 115a, 115b) may be made of a substance that can be used in the electron transport layers (114, 114a, 114b).

[0221] Furthermore, a composite material obtained by mixing an organic compound and an electron donor may be used in the electron injection layers (115, 115a, 115b). Such a composite material has excellent electron injection and electron transport properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material that is excellent in transporting the generated electrons, and specifically, for example, the substance that constitutes the electron transport layer 114 described above (metal complex, or heteroaromatic compound, etc.) can be used. As the electron donor, any substance that exhibits electron-donating properties to the organic compound is acceptable. Specifically, alkali metals, alkaline earth metals, or rare earth metals are preferred, such as lithium, sodium, cesium, magnesium, calcium, erbium, and ytterbium. Alkali metal oxides or alkaline earth metal oxides are also preferred, such as lithium oxide, calcium oxide, and barium oxide. Lewis bases such as magnesium oxide can also be used. Furthermore, organic compounds such as tetrathiafulvalene (abbreviated as TTF) can also be used.

[0222] The light-emitting layer, hole injection layer, hole transport layer, electron transport layer, and electron injection layer described above can be formed by methods such as vapor deposition (including vacuum deposition), inkjet printing, coating, and gravure printing. In addition to the materials described above, inorganic compounds such as quantum dots or polymer compounds (oligomers, dendrimers, polymers, etc.) may also be used for the light-emitting layer, hole injection layer, hole transport layer, electron transport layer, and electron injection layer.

[0223] Furthermore, the quantum dots may include colloidal quantum dots, alloy quantum dots, core-shell quantum dots, core quantum dots, etc. Quantum dots containing elemental groups from groups 2 and 16, 13 and 15, 13 and 17, 11 and 17, or 14 and 15 may also be used. Alternatively, quantum dots containing elements such as cadmium (Cd), selenium (Se), zinc (Zn), sulfur (S), phosphorus (P), indium (In), tellurium (Te), lead (Pb), gallium (Ga), arsenic (As), and aluminum (Al) may be used.

[0224] <Pair of electrodes> The first electrode 101 and the second electrode 102 function as the anode or cathode of the light-emitting device. The first electrode 101 and the second electrode 102 can be formed using metals, alloys, conductive compounds, mixtures thereof, or laminates.

[0225] Preferably, one of the first electrode 101 or the second electrode 102 is formed of a conductive material having the function of reflecting light. Examples of such conductive materials include aluminum (Al) or alloys containing Al. Examples of alloys containing Al include alloys containing Al and L (where L represents one or more of titanium (Ti), neodymium (Nd), nickel (Ni), and lanthanum (La)), such as alloys containing Al and Ti, or Al, Ni, and La. Aluminum has low electrical resistivity and high light reflectivity. Furthermore, since aluminum is abundant in the Earth's crust and inexpensive, using aluminum can reduce the manufacturing cost of light-emitting devices. In addition, alloys containing silver (Ag), or Ag and N (where N represents one or more of yttrium (Y), Nd, magnesium (Mg), ytterbium (Yb), Al, Ti, gallium (Ga), zinc (Zn), indium (In), tungsten (W), manganese (Mn), tin (Sn), iron (Fe), Ni, copper (Cu), palladium (Pd), iridium (Ir), or gold (Au) may be used. Examples of silver-containing alloys include alloys containing silver, palladium, and copper; alloys containing silver and copper; alloys containing silver and magnesium; alloys containing silver and nickel; alloys containing silver and gold; and alloys containing silver and ytterbium. Other transition metals such as tungsten, chromium (Cr), molybdenum (Mo), copper, and titanium can also be used.

[0226] Furthermore, the light emitted from the light-emitting layer is extracted through one or both of the first electrode 101 and the second electrode 102. Therefore, it is preferable that at least one of the first electrode 101 and the second electrode 102 be made of a conductive material that has the function of transmitting light. The conductive material has a visible light transmittance of 40% to 100%, preferably 60% to 100%, and a resistivity of 1 × 10⁻¹⁶. −２Examples of conductive materials include those with a conductivity of Ω·cm or less.

[0227] Furthermore, the first electrode 101 and the second electrode 102 may be formed from a conductive material having the function of transmitting light and the function of reflecting light. The conductive material has a visible light reflectance of 20% to 80%, preferably 40% to 70%, and a resistivity of 1 × 10⁻⁶. −２ Examples of conductive materials include those with a conductivity of Ω·cm or less. For example, they can be formed using one or more types of conductive metals, alloys, or conductive compounds. Specifically, for example, metal oxides such as indium tin oxide (ITO), indium tin oxide containing silicon or silicon oxide (abbreviated as ITSO), indium zinc oxide, indium tin oxide containing titanium, indium titanium oxide, tungsten oxide, and indium oxide containing zinc oxide can be used. In addition, a thin metal film that transmits light (preferably with a thickness of 1 nm to 30 nm) can be used. As a metal, for example, Ag can be used. As an alloy, alloys such as Ag and Al, Ag and Mg, Ag and Au, Ag and Yb can be used.

[0228] In this specification, a material having the function of transmitting light is any material that has the function of transmitting visible light and is conductive, and may include, for example, oxide conductors represented by ITO as described above, oxide semiconductors, or organic conductors containing organic matter. Examples of organic conductors containing organic matter include composite materials obtained by mixing an organic compound with an electron donor, and composite materials obtained by mixing an organic compound with an electron acceptor. Inorganic carbon-based materials such as graphene may also be used. The resistivity of the material is preferably 1 × 10⁻⁶. ５ Ω·cm or less, more preferably 1 × 10⁻⁶ ４ It is less than or equal to Ω·cm.

[0229] Alternatively, one or both of the first electrode 101 and the second electrode 102 may be formed by stacking multiple of the above materials.

[0230] Furthermore, to improve light extraction efficiency, a material with a higher refractive index than the electrode may be formed in contact with an electrode that has the function of transmitting light. Such a material can be any material that has the function of transmitting visible light, and may or may not be conductive. For example, in addition to the oxide conductors mentioned above, oxide semiconductors and organic materials can be used. Examples of organic materials include the materials exemplified in the light-emitting layer, hole injection layer, hole transport layer, electron transport layer, or electron injection layer. Inorganic carbon-based materials or thin metal films that transmit light to a certain extent can also be used, and multiple layers with film thicknesses of several nanometers to tens of nanometers may be stacked.

[0231] When the first electrode 101 or the second electrode 102 functions as a cathode, it is preferable to use a material with a small work function (3.8 eV or less). For example, elements belonging to Group 1 or Group 2 of the periodic table (alkali metals such as lithium, sodium, and cesium; alkaline earth metals such as calcium and strontium; magnesium, etc.), alloys containing these elements (e.g., Ag and Mg, Al and Li), rare earth metals such as europium (Eu) and Yb, alloys containing these rare earth metals, alloys containing aluminum and silver, etc. can be used.

[0232] Furthermore, when using the first electrode 101 or the second electrode 102 as an anode, it is preferable to use a material with a large work function (4.0 eV or more).

[0233] Furthermore, the first electrode 101 and the second electrode 102 may be laminated from a conductive material having the function of reflecting light and a conductive material having the function of transmitting light. In that case, the first electrode 101 and the second electrode 102 are preferable because they can have a function to adjust the optical distance so that the light from each light-emitting layer resonates at a desired wavelength and the light of that wavelength is strengthened.

[0234] The first electrode 101 and the second electrode 102 can be deposited using methods such as sputtering, vapor deposition, printing, coating, MBE (Molecular Beam Epitaxy), CVD, pulsed laser deposition, ALD (Atomic Layer Deposition), etc., as appropriate.

[0235] ≪Charge Generation Layer (Intermediate Layer)≫ The charge generation layer 106 has the function of injecting electrons into the organic compound layer 103a and holes into the organic compound layer 103b when a voltage is applied between the first electrode (anode) 101 and the second electrode (cathode) 102. The charge generation layer 106 may be a configuration in which an electron acceptor is added to a hole transport material (also called a P-type layer), or a configuration in which an electron donor is added to an electron transport material (also called an electron injection buffer layer). Furthermore, both of these configurations may be laminated. In addition, an electron relay layer may be provided between the P-type layer and the electron injection buffer layer. By forming the charge generation layer 106 using the materials described above, it is possible to suppress the increase in driving voltage when an organic compound layer including an emissive layer is laminated.

[0236] In the charge generation layer 106, when an electron acceptor is added to a hole-transporting material which is an organic compound (P-type layer), the hole-transporting material shown in this embodiment can be used. Furthermore, as the electron acceptor, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviated as F) can be used. ４ Examples include -TCNQ), chloranil, etc. Also, oxides of metals belonging to groups 4 through 8 of the periodic table can be used. Specifically, examples include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide. The above-mentioned acceptor materials may also be used. Furthermore, the materials constituting the P-type layer may be used as a mixed film, or single films containing each material may be laminated.

[0237] Furthermore, in the charge generation layer 106, if an electron donor is added to the electron transport material (electron injection buffer layer), the electron transport material may be the electron transport material shown in this embodiment. Alternatively, the organic compound of Embodiment 1 can be used.

[0238] Furthermore, alkali metals, alkaline earth metals, rare earth metals, or metals belonging to groups 2 and 13 of the periodic table, as well as their oxides and carbonates, can be used as electron donors. Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide (Li) ２ It is preferable to use o), cesium carbonate, etc. Alternatively, an organic compound such as tetrathianaphthalene may be used as an electron donor.

[0239] In the charge generation layer 106, when an electron relay layer is provided between the P-type layer and the electron injection buffer layer, the electron relay layer contains at least an electron-transporting material and has the function of preventing interaction between the electron injection buffer layer and the P-type layer and smoothly transferring electrons. Preferably, the LUMO level of the electron-transporting material contained in the electron relay layer is between the LUMO level of the acceptor material in the P-type layer and the LUMO level of the electron-transporting material contained in the electron transport layer in contact with the charge generation layer 106. The specific energy level of the LUMO level of the electron-transporting material used in the electron relay layer is preferably -5.0 eV or higher, more preferably -5.0 eV or higher and -3.0 eV or lower. Preferably, as the electron-transporting material used in the electron relay layer, a phthalocyanine-based material or a metal complex having a metal-oxygen bond and an aromatic ligand is used.

[0240] Although Figure 4D shows a configuration in which two organic compound layers 103 are stacked, a stacked structure of organic compound layers including three or more light-emitting layers may be used by providing a charge generation layer between different light-emitting layers.

[0241] <<Cap Layer>> Although not shown in Figures 4A to 4E, a cap layer may be provided on the second electrode 102 of the light-emitting device. For example, a material with a high refractive index can be used for the cap layer. By providing a cap layer on the second electrode 102, the extraction efficiency of the light emitted from the second electrode 102 can be improved.

[0242] Specific examples of materials that can be used in the cap layer include 5,5'-diphenyl-2,2'-di-5H-[1]benzothieno[3,2-c]carbazole (abbreviated as BisBTc) and 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviated as DBT3P-II).

[0243] <Substrate> Furthermore, a light-emitting device according to one aspect of the present invention may be manufactured on a substrate made of glass, plastic, or the like. The order in which the components are manufactured on the substrate may be either by stacking them sequentially from the first electrode 101 side, or by stacking them sequentially from the second electrode 102 side.

[0244] Furthermore, as a substrate on which a light-emitting device according to one aspect of the present invention can be formed, for example, glass, quartz, or plastic can be used. A flexible substrate may also be used. A flexible substrate is a substrate that can be bent (flexible), and examples include plastic substrates made of polycarbonate or polyarylate. Films, inorganic vapor-deposited films, etc., can also be used. However, other materials are also acceptable as long as they function as a support in the manufacturing process of the light-emitting device and optical element. Alternatively, any material that has the function of protecting the light-emitting device and optical element is acceptable.

[0245] For example, in this specification and the like, a light-emitting device can be formed using various substrates. The type of the substrate is not particularly limited. As an example of the substrate, there are a semiconductor substrate (e.g., a single-crystalline substrate such as a silicon substrate), an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a metal substrate, a stainless-steel substrate, a substrate having a stainless-steel foil, a tungsten substrate, a substrate having a tungsten foil, a flexible substrate, a laminated film, a cellulose nanofiber (CNF) containing a fibrous material, paper, or a base film. As an example of the glass substrate, there are barium borosilicate glass, aluminoborosilicate glass, or soda lime glass. Examples of the flexible substrate, the laminated film, the base film, etc. include the following. For example, there are plastics typified by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), and polytetrafluoroethylene (PTFE). Or, as an example, there is an acrylic resin. Or, as an example, there are polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride. Or, as an example, there are resins such as polyamide, polyimide, aramid, or epoxy, an inorganic vapor deposition film, or papers.

[0246] Also, as the substrate, a flexible substrate may be used, and a light-emitting device may be formed directly on the flexible substrate. Or, a release layer may be provided between the substrate and the light-emitting device. The release layer can be used to separate from the substrate after partially or completely completing the light-emitting device thereon and transfer it to another substrate. At that time, the light-emitting device can also be transferred to a substrate with low heat resistance or a flexible substrate. Incidentally, for the above-mentioned release layer, for example, a configuration of a laminated structure of an inorganic film of a tungsten film and a silicon oxide film, and a configuration in which a resin film such as polyimide is formed on the substrate can be used.

[0247] That is, a light-emitting device may be formed using a certain substrate, and then the light-emitting device may be transferred to another substrate and disposed on the other substrate. As an example of the substrate to which the light-emitting device is transferred, in addition to the substrates described above, there are cellophane substrates, stone substrates, wood substrates, cloth substrates (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester), or recycled fibers (acetate, cupra, rayon, recycled polyester), etc.), leather substrates, or rubber substrates, etc. By using these substrates, a light-emitting device that is difficult to break, a light-emitting device with high heat resistance, a light-emitting device with reduced weight, or a light-emitting device with reduced thickness can be obtained.

[0248] Also, for example, a field-effect transistor (FET) may be formed on the above-described substrate, and a light-emitting device may be fabricated on an electrode electrically connected to the FET. Thereby, an active matrix type display device that controls the driving of the light-emitting device by the FET can be fabricated.

[0249] In addition, in this embodiment, one aspect of the present invention has been described. Or, in other embodiments, one aspect of the present invention is described. However, one aspect of the present invention is not limited to these. That is, in this embodiment and other embodiments, various aspects of the invention are described, so one aspect of the present invention is not limited to a specific aspect. For example, as one aspect of the present invention, an example when applied to a light-emitting device has been shown, but one aspect of the present invention is not limited to this. For example, in some cases, or depending on the situation, one aspect of the present invention may not be applied to the light-emitting device.

[0250] As described above, the configuration shown in this embodiment can be used in appropriate combination with the configuration shown in other embodiments.

[0251] (Embodiment 3) As illustrated in FIGS. 5A and 5B, the light-emitting device 130 constitutes a display device formed in plurality on the insulating layer 175. In this embodiment, a display device according to one aspect of the present invention will be described in detail.

[0252] The display device 100 has a pixel section 177 in which a plurality of pixels 178 are arranged in a matrix. The pixels 178 include sub-pixels 110R, sub-pixels 110G, and sub-pixels 110B.

[0253] In this specification, when describing matters common to, for example, sub-pixels 110R, 110G, and 110B, they may be referred to simply as sub-pixel 110. Similarly, when describing matters common to other components distinguished by letters, the letters may be omitted and the corresponding symbols used.

[0254] Sub-pixel 110R emits red light, sub-pixel 110G emits green light, and sub-pixel 110B emits blue light. This allows an image to be displayed on the pixel section 177. In this embodiment, three sub-pixels of red (R), green (G), and blue (B) are used as an example, but combinations of other colors of sub-pixels may also be used. Furthermore, the number of sub-pixels is not limited to three, but may be four or more. Examples of four sub-pixels include four sub-pixels of R, G, B, and white (W), four sub-pixels of R, G, B, and yellow (Y), and four sub-pixels of R, G, B, and infrared (IR).

[0255] In this specification and other documents, the row direction may be referred to as the X direction and the column direction as the Y direction. The X and Y directions intersect, for example, perpendicularly.

[0256] Figure 5A shows an example where subpixels of different colors are arranged in the X direction, and subpixels of the same color are arranged in the Y direction. Alternatively, subpixels of different colors may be arranged in the Y direction, and subpixels of the same color may be arranged in the X direction.

[0257] A connecting portion 140 and a region 141 may be provided on the outside of the pixel portion 177. The region 141 is provided between the pixel portion 177 and the connecting portion 140. An organic compound layer 103 is provided in the region 141. A conductive layer 151C is provided in the connecting portion 140.

[0258] Figure 5A shows an example where region 141 and connection portion 140 are located to the right of the pixel portion 177, but the positions of region 141 and connection portion 140 are not particularly limited. Also, region 141 and connection portion 140 may be singular or multiple.

[0259] Figure 5B is an example of a cross-sectional view between the dashed line A1 and A2 in Figure 5A. As shown in Figure 5A, the display device 100 has 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, insulating layer 174, and insulating layer 173 are provided with openings that reach the conductive layer 172, and plugs 176 are provided to fill these openings.

[0260] In the pixel section 177, a light-emitting device 130 is provided on an insulating layer 175 and a plug 176. A protective layer 131 is provided so as to cover the light-emitting device 130. A substrate 120 is bonded to the protective layer 131 by a resin layer 122. Preferably, an inorganic insulating layer 125 and an insulating layer 127 on the inorganic insulating layer 125 are provided between adjacent light-emitting devices 130.

[0261] In Figure 5B, multiple cross-sections of the inorganic insulating layer 125 and the insulating layer 127 are shown, but when the display device 100 is viewed from above, it is preferable that the inorganic insulating layer 125 and the insulating layer 127 are connected as one unit. In other words, it is preferable that the insulating layer 127 is an insulating layer having an opening on the first electrode.

[0262] In Figure 5B, the light-emitting device 130 is shown as light-emitting device 130R, light-emitting device 130G, and light-emitting device 130B. Light-emitting devices 130R, 130G, and 130B emit different colors from each other. For example, light-emitting device 130R can emit red light, light-emitting device 130G can emit green light, and light-emitting device 130B can emit blue light. In addition, light-emitting devices 130R, 130G, or 130B may emit other visible light or infrared light.

[0263] One embodiment of the present invention can be a top-emission type, for example, which emits light in the opposite direction to the substrate on which the light-emitting device is formed. Alternatively, one embodiment of the present invention may be a bottom-emission type.

[0264] Examples of light-emitting materials in the light-emitting device 130 include organic compounds or organometallic complexes such as fluorescent materials, phosphorescent materials, and thermally activated delayed fluorescence (TADF) materials. Inorganic compounds such as quantum dots may also be used.

[0265] The light-emitting device 130R has the configuration shown in Figure 1A. It includes a first electrode (pixel electrode) consisting 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. The common layer 104 may or may not be provided, but its provision is preferable because it reduces damage to the organic compound layer 103R during processing. If the common layer 104 is provided, it is preferable that the common layer 104 is an electron injection layer. Furthermore, if the common layer 104 is provided, the laminated structure of the organic compound layer 103R and the common layer 104 corresponds to the organic compound layer 103 in Embodiment 2.

[0266] The light-emitting device 130G has the configuration shown in Figure 1A. It includes a first electrode (pixel electrode) consisting 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. The common layer 104 may or may not be provided, but its provision is preferable because it reduces damage to the organic compound layer 103G during processing. If the common layer 104 is provided, it is preferable that the common layer 104 is an electron injection layer. Furthermore, if the common layer 104 is provided, the laminated structure of the organic compound layer 103G and the common layer 104 corresponds to the organic compound layer 103 in Embodiment 2.

[0267] The light-emitting device 130B has the configuration shown in Figure 1A. It includes a first electrode (pixel electrode) consisting 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. The common layer 104 may or may not be provided, but its provision is preferable because it reduces damage to the organic compound layer 103B during processing. If the common layer 104 is provided, it is preferable that the common layer 104 is an electron injection layer. Furthermore, if the common layer 104 is provided, the laminated structure of the organic compound layer 103B and the common layer 104 corresponds to the organic compound layer 103 in Embodiment 2.

[0268] Of the pixel electrodes and common electrodes in a light-emitting device, one functions as the anode and the other as the cathode. In the following explanation, unless otherwise specified, it is assumed that the pixel electrodes function as the anode and the common electrodes function as the cathode.

[0269] The organic compound layers 103R, 103G, and 103B are independently arranged in an island-like configuration for each light-emitting device. By providing the organic compound layer 103 in an island-like configuration for each light-emitting device 130, leakage current between adjacent light-emitting devices 130 can be suppressed even in high-definition display devices. This prevents crosstalk and enables the realization of a display device with extremely high contrast. In particular, it enables the realization of a display device with high current efficiency at low brightness.

[0270] The island-shaped organic compound layer 103 is formed by depositing an EL film and processing the EL film using a lithography method.

[0271] Furthermore, in a display device according to one aspect of the present invention, it is preferable that the first electrode (pixel electrode) of the light-emitting device be in a stacked configuration. For example, in the example shown in Figure 5B, the first electrode of the light-emitting device 130 is in a stacked configuration of a conductive layer 151 and a conductive layer 152. For example, when the display device 100 is a top-emission type and the pixel electrode of the light-emitting device 130 functions as an anode, it is preferable that the conductive layer 151 is a layer with high reflectivity for visible light, and the conductive layer 152 is a layer that, for example, transmits visible light and has a large work function. When the display device 100 is a top-emission type, the higher the reflectivity of the pixel electrode for visible light, the higher the efficiency of extracting light emitted by the organic compound layer 103. Also, when the pixel electrode functions as an anode, the larger the work function of the pixel electrode, the easier it is to inject holes into the organic compound layer 103. Based on the above, by making the pixel electrodes of the light-emitting device 130 a stacked structure consisting of a conductive layer 151 with high reflectivity for visible light and a conductive layer 152 with a large work function, the light-emitting device 130 can be made into a light-emitting device with high light extraction efficiency and low driving voltage.

[0272] When the conductive layer 151 is a layer with high reflectivity to visible light, it is preferable that the reflectivity of the conductive layer 151 to visible light be, for example, 40% to 100% or 70% to 100%. Furthermore, when the conductive layer 152 is an electrode that transmits visible light, it is preferable that its transmittance to visible light be, for example, 40% or more.

[0273] In cases where the pixel electrode has a stacked structure consisting of multiple layers, the pixel electrode may be altered due to reactions between these layers, for example. For instance, when a film formed after the pixel electrode is created is removed by a wet etching method, galvanic corrosion may occur when the chemical solution comes into contact with the pixel electrode.

[0274] Therefore, in the display device 100 of this embodiment, an insulating layer 156 is formed on the side surfaces of the conductive layer 151 and the conductive layer 152. This makes it possible to suppress contact of the chemical solution with the conductive layer 151 even when removing a film formed after the formation of a pixel electrode having the conductive layer 151 and the conductive layer 152 by a wet etching method. Consequently, the occurrence of galvanic corrosion on the pixel electrode can be suppressed. As a result, the display device 100 can be manufactured using a method with a high yield, making it a low-cost display device. Furthermore, since the occurrence of defects in the display device 100 can be suppressed, the display device 100 can be a highly reliable display device.

[0275] For example, a metallic material can be used as the conductive layer 151. 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), and alloys containing these in appropriate combinations can also be used.

[0276] As the conductive layer 152, an oxide having one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon can be used. For example, it is preferable to use a conductive oxide containing one or more of the following: 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. In particular, indium tin oxide containing silicon has a large work function, for example, a work function of 4.0 eV or more, so it can be suitably used as the conductive layer 152.

[0277] The conductive layer 151 may be a laminated structure of multiple layers having different materials, and the conductive layer 152 may be a laminated structure of multiple layers having different materials. In this case, the conductive layer 151 may have a layer made of a material that can be used for the conductive layer 152, such as a conductive oxide, and the conductive layer 152 may have a layer made of a material that can be used for the conductive layer 151, such as a metallic material. For example, if 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 made of a material that can be used for the conductive layer 152.

[0278] Furthermore, the end of the insulating layer 156 may have a tapered shape. Specifically, by having a tapered shape with a taper angle of less than 90° at the end of the insulating layer 156, the coverage of structures provided along the side surface of the insulating layer 156 can be improved.

[0279] Next, an example of a method for manufacturing a display device 100 having the configuration shown in Figure 5A will be described using Figures 6 to 11. The light-emitting device of the display device 100 is formed by a manufacturing process that includes a treatment using water, in which the organic compound layer is formed. Even when the light-emitting device of a display device according to one aspect of the present invention is manufactured by a manufacturing method that includes a treatment using water, problems such as the dissolution of the layer containing the organic compound and the penetration of chemical solutions into the layer using the organic compound can be prevented, and a light-emitting device with good characteristics can be provided.

[0280] [Examples of Fabrication Methods] Thin films (insulating films, semiconductor films, and conductive films, etc.) that constitute a display device can be formed using sputtering, chemical vapor deposition (CVD), vacuum deposition, pulsed laser deposition (PLD), or ALD. CVD methods include plasma enhanced CVD (PECVD) and thermal CVD. One type of thermal CVD is metal-organic vapor deposition (MOCVD).

[0281] In addition, thin films (such as insulating films, semiconductor films, and conductive films) that make up the display device can be formed by wet film formation methods such as spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, doctor blade method, slit coating, roll coating, curtain coating, or knife coating.

[0282] In particular, for the fabrication of light-emitting devices, vacuum processes such as vapor deposition and solution processes such as spin coating and inkjet can be used. Examples of vapor deposition methods include physical vapor deposition (PVD) methods such as sputtering, ion plating, ion beam evaporation, molecular beam epitaxy, and vacuum evaporation, and chemical vapor deposition (CVD) methods. In particular, for functional layers (such as hole injection layers, hole transport layers, hole blocking layers, light-emitting layers, electron blocking layers, electron transport layers, and electron injection layers) contained in organic compound layers, they can be formed by methods such as vapor deposition (such as vacuum evaporation), coating methods (such as dip coating, die coating, bar coating, spin coating, spray coating), and printing methods (such as inkjet, screen (stencil printing), offset (lithography), flexo (letterpress), gravure, or microcontact).

[0283] When processing the thin films that make up the display device, for example, it can be processed using a lithography method. Alternatively, the thin film may be processed by a nanoimprint method, sandblasting method, lift-off method, etc. Also, island-shaped thin films may be directly formed by a film formation method using a shielding mask such as a metal mask.

[0284] As the lithography method, for example, a photolithography method can be used. There are typically two representative methods for the photolithography method. One is a method in which a resist mask is formed on the thin film to be processed, and the thin film is processed, for example, by etching, and then the resist mask is removed. The other is a method in which a photosensitive thin film is formed and then exposed and developed to process the thin film into a desired shape.

[0285] In photolithography, the light used for exposure can be, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or a mixture thereof. Other light sources such as ultraviolet light, KrF laser light, or ArF laser light can also be used. Exposure may also be performed using immersion lithography. Furthermore, extreme ultraviolet (EUV) light or X-rays may be used as the light source for exposure. An electron beam can also be used instead of the light source for exposure. Using extreme ultraviolet light, X-rays, or an electron beam is preferable because it enables extremely fine processing. Note that a photomask is not required when exposure is performed by scanning a beam such as an electron beam.

[0286] For etching thin films, dry etching, wet etching, or sandblasting methods can be used.

[0287] First, as shown in Figure 6A, 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 layers 172 and 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.

[0288] As the substrate, a substrate with sufficient heat resistance to withstand subsequent heat treatment can be used. When using an insulating substrate, glass substrates, quartz substrates, sapphire substrates, ceramic substrates, or organic resin substrates can be used. In addition, semiconductor substrates such as single-crystal semiconductor substrates, polycrystalline semiconductor substrates, compound semiconductor substrates such as silicon-germanium, and SOI substrates made from silicon or silicon carbide can be used.

[0289] Next, as shown in Figure 6A, openings reaching the conductive layer 172 are formed in the insulating layer 175, insulating layer 174, and insulating layer 173. Subsequently, a plug 176 is formed to fill these openings.

[0290] Next, as shown in Figure 6A, a conductive film 151f, which will later become conductive layers 151R, 151G, 151B, and 151C, is formed on the plug 176 and the insulating layer 175. For example, sputtering or vacuum deposition can be used to form the conductive film 151f. Also, a metallic material can be used as the conductive film 151f.

[0291] Next, as shown in Figure 6A, a conductive film 152f is formed on the conductive film 151f, which will later become conductive layers 152R, 152G, 152B, and 152C. For example, sputtering or vacuum deposition can be used to form the conductive film 152f. Alternatively, a conductive oxide can be used as the conductive film 152f. Or, a laminated structure can be applied to the conductive film 152f, consisting of a film using a metallic material and a film using a conductive oxide on that film. For example, a laminated structure can be applied to the conductive film 152f, consisting of a film using titanium, silver, or a silver-containing alloy and a film using a conductive oxide on that film.

[0292] Furthermore, the ALD method can be used to form the conductive film 152f. In this case, the conductive film 152f can be an oxide having one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon. In this case, the conductive film 152f can be formed by repeating a cycle in which one cycle consists of introducing a precursor (generally sometimes called a precursor or metal precursor), purging the precursor, introducing an oxidizing agent (generally sometimes called a reactant or nonmetal precursor), and purging the oxidizing agent. When forming an oxide film containing multiple types of metals, such as indium tin oxide, as the conductive film 152f, the metal composition can be controlled by varying the number of cycles for each type of precursor.

[0293] For example, when forming an indium tin oxide film as the conductive film 152f, an indium-containing precursor is introduced, the precursor is purged, and an oxidizing agent is introduced to form an In-O film. Then, a tin-containing precursor is introduced, the precursor is purged, and an oxidizing agent is introduced to form a Sn-O film. Here, by making the number of cycles for In-O film formation greater than the number of cycles for Sn-O film formation, the number of In atoms in the conductive film 152f can be made greater than the number of Sn atoms.

[0294] Furthermore, for example, when a zinc oxide film is formed as the conductive film 152f, a Zn-O film is formed using the above procedure. Furthermore, for example, when an aluminum zinc oxide film is formed as the conductive film 152f, a Zn-O film and an Al-O film are formed using the above procedure. Furthermore, for example, when a titanium oxide film is formed as the conductive film 152f, a Ti-O film is formed using the above procedure. Furthermore, for example, when an indium tin oxide film containing silicon is formed as the conductive film 152f, an In-O film, a Sn-O film, and a Si-O film are formed using the above procedure. Furthermore, for example, when a zinc oxide film containing gallium is formed, a Ga-O film and a Zn-O film are formed using the above procedure.

[0295] As an indium-containing precursor, for example, triethylindium, trimethylindium, or [1,1,1-trimethyl-N-(trimethylsilyl)amide]-indium can be used. As a tin-containing precursor, for example, tin chloride or tetrakis(dimethylamide)tin can be used. As a zinc-containing precursor, for example, diethylzinc or dimethylzinc can be used. As a gallium-containing precursor, for example, triethylgallium can be used. As a titanium-containing precursor, for example, titanium chloride, tetrakis(dimethylamide)titanium, or tetraisopropyl titanate can be used. As an aluminum-containing precursor, for example, aluminum chloride or trimethylaluminum can be used. As a silicon-containing precursor, trisilylamine, bis(diethylamino)silane, tris(dimethylamino)silane, bis(tert-butylamino)silane, or bis(ethylmethylamino)silane can be used. In addition, water vapor, oxygen plasma, or ozone gas can be used as an oxidizing agent.

[0296] Next, as shown in Figure 6A, a resist mask 191 is formed on the conductive film 151f and the conductive film 152f. The resist mask 191 can be formed by applying a photosensitive material (photoresist), exposing it to light, and developing it.

[0297] Next, as shown in Figure 6B, conductive films 151f and 152f in areas that do not overlap with the resist mask 191 are removed, for example, by etching, specifically by dry etching, to form a pixel electrode having a conductive layer 151 and a conductive layer 152. If the conductive film 151f includes a layer using a conductive oxide such as indium tin oxide, this layer may be removed by wet etching. This forms the conductive layer 151 and the conductive layer 152. If, for example, a part of the conductive film 151f is removed by dry etching, a recess may be formed in the area of ​​the insulating layer 175 that does not overlap with the conductive layer 151.

[0298] Alternatively, the conductive film 152f may be processed using lithography to form conductive layers 152R, 152G, 152B, and 152C, and then the conductive film 151f may be processed using conductive layers 152R, 152G, 152B, and 152C as a mask. Specifically, for example, after forming a resist mask, a portion of the conductive film 152f is removed by etching. The conductive film 152f can be removed by, for example, wet etching. Alternatively, the conductive film 152f may be removed by dry etching. After that, the conductive film 151f may be removed by wet etching.

[0299] Here, it is preferable to perform a hydrophobic treatment on the conductive layer 152. The hydrophobic treatment can change the surface to be treated from hydrophilic to hydrophobic, or increase the hydrophobicity of the surface to be treated. By performing a hydrophobic treatment on the conductive layer 152, the adhesion between the conductive layer 152 and the organic compound layer 103 formed in a later step can be improved, and film peeling can be suppressed. However, the hydrophobic treatment is not required.

[0300] Next, as shown in Figure 6C, the resist mask 191 is removed. The resist mask 191 can be removed, for example, by ashing using oxygen plasma. Alternatively, oxygen gas and CF ４ , C ４ F ８ SF ６ CHF ３ , Cl ２ , H ２ O, BCl ３ Alternatively, a Group 18 element such as He may be used. Or, the resist mask 191 may be removed by wet etching.

[0301] Next, as shown in Figure 6D, insulating films 156f, which will later become insulating layers 156R, 156G, 156B, and 156C, are formed on conductive layers 151R and 152R, conductive layers 151G and 152G, conductive layers 151B and 152B, conductive layers 151C and 152C, and insulating layer 175. For forming the insulating film 156f, for example, CVD, ALD, sputtering, or vacuum deposition can be used.

[0302] Inorganic materials can be used for the insulating film 156f. For example, inorganic insulating films such as oxide insulating films, nitride insulating films, oxidative nitride insulating films, or nitride-oxide insulating films can be used for the insulating film 156f. For example, silicon-containing oxide insulating films, nitride insulating films, oxidative nitride insulating films, or nitride-oxide insulating films can be used as the insulating film 156f. For example, silicon oxidative nitride can be used as the insulating film 156f.

[0303] Next, as shown in Figure 6E, insulating layers 156R, 156G, 156B, and 156C are formed by processing the insulating film 156f. For example, the insulating layer 156 can be formed by etching the upper surface of the insulating film 156f substantially uniformly. This uniform etching and planarization is also called etch-back processing. The insulating layer 156 may also be formed using lithography.

[0304] Next, as shown in Figure 7A, an organic compound film 103Rf, which will later become the organic compound layer 103R, is formed on the conductive layer 152R, conductive layer 152G, conductive layer 152B, insulating layer 156R, insulating layer 156G, insulating layer 156B, and insulating layer 175.

[0305] As shown in Figure 7A, no organic compound film 103Rf is formed on the conductive layer 152C. For example, by using a mask to define the film deposition area (also called an area mask or rough metal mask, to distinguish it from a fine metal mask), the organic compound film 103Rf can be deposited only in the desired region. By employing a film deposition process using an area mask and a processing process using a resist mask, a light-emitting device can be manufactured using a relatively simple process.

[0306] The organic compound film 103Rf can be formed, for example, by a vapor deposition method, specifically a vacuum vapor deposition method. Alternatively, the organic compound film 103Rf may be formed by methods such as a transfer method, a printing method, an inkjet method, or a coating method.

[0307] Next, as shown in Figure 7A, a sacrificial film 158Rf, which will later become a sacrificial layer 158R, and a mask film 159Rf, which will later become a mask layer 159R, are formed in order on the organic compound film 103Rf, the conductive layer 152C, and the insulating layer 175, respectively.

[0308] In this embodiment, an example is shown in which the mask film is formed with a two-layer structure consisting of a sacrificial film 158Rf and a mask film 159Rf. However, the mask film may also be a single-layer structure or a laminated structure of three or more layers.

[0309] By providing a sacrificial layer on the organic compound film 103Rf, the damage sustained by the organic compound film 103Rf during the manufacturing process of the display device can be reduced, thereby improving the reliability of the light-emitting device.

[0310] For 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 high etching selectivity ratio with the organic compound film 103Rf. For the mask film 159Rf, a film with a high etching selectivity ratio with the sacrificial film 158Rf is used.

[0311] Furthermore, the sacrificial film 158Rf and the mask film 159Rf are formed at a temperature lower than the heat resistance temperature of the organic compound film 103Rf. The substrate temperature when forming the sacrificial film 158Rf and the mask film 159Rf is typically 200°C or lower, preferably 150°C or lower, more preferably 120°C or lower, more preferably 100°C or lower, and even more preferably 80°C or lower.

[0312] It is preferable to use films that can be removed by wet etching for the sacrificial film 158Rf and the mask film 159Rf. By using wet etching, the damage to the organic compound film 103Rf during processing of the sacrificial film 158Rf and the mask film 159Rf can be reduced compared to when using dry etching.

[0313] For the formation of the sacrificial film 158Rf and the mask film 159Rf, for example, sputtering, ALD (thermal ALD, PEALD), CVD, and vacuum deposition can be used. Alternatively, they may be formed using the wet film formation method described above.

[0314] Furthermore, it is preferable that the sacrificial film 158Rf, which is formed in contact with the organic compound film 103Rf, is formed using a method that causes less damage to the organic compound film 103Rf than the mask film 159Rf. For example, it is preferable to form the sacrificial film 158Rf using the ALD method or vacuum deposition method rather than the sputtering method.

[0315] The sacrificial film 158Rf and the mask film 159Rf can be, for example, one or more of the following: metal films, alloy films, metal oxide films, semiconductor films, organic insulating films, and inorganic insulating films.

[0316] The sacrificial film 158Rf and the mask film 159Rf can be made of metallic 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 such metallic materials. In particular, it is preferable to use low-melting-point materials such as aluminum or silver. It is preferable to use a metallic material capable of shielding ultraviolet rays for one or both of the sacrificial film 158Rf and the mask film 159Rf, as this can suppress the irradiation of the organic compound film 103Rf with ultraviolet rays and thus suppress the degradation of the organic compound film 103Rf.

[0317] Furthermore, the sacrificial film 158Rf and the mask film 159Rf can be made from 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), and silicon-containing indium tin oxide, respectively.

[0318] In addition, element M (where M is one or more elements selected from aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium) may be used instead of gallium.

[0319] Furthermore, it is preferable to use films containing a material that has light-shielding properties, particularly against ultraviolet light, as the sacrificial film and mask film. Various materials can be used as the light-shielding material, such as metals, insulators, semiconductors, and metalloids that have light-shielding properties against ultraviolet light. However, since part or all of the sacrificial film and mask film will be removed in a later process, it is preferable that the film be processable by etching, and in particular, that it has good processability.

[0320] As sacrificial films and mask films, semiconductor materials such as silicon or germanium are preferred due to their high affinity with semiconductor manufacturing processes. Alternatively, oxides or nitrides of the above semiconductor materials can be used. Alternatively, nonmetallic materials such as carbon, or compounds thereof, can be used. Alternatively, metals such as titanium, tantalum, tungsten, chromium, and aluminum, or alloys containing one or more of these, can be used. Alternatively, oxides containing the above metals such as titanium oxide or chromium oxide, or nitrides such as titanium nitride, chromium nitride, or tantalum nitride can be used.

[0321] By using sacrificial and mask films containing materials that are light-shielding against ultraviolet light, it is possible to suppress the irradiation of the organic compound layer with ultraviolet light during the exposure process, for example. By suppressing damage to the organic compound layer from ultraviolet light, the reliability of the light-emitting device can be improved.

[0322] Furthermore, a film containing a material that has light-shielding properties against ultraviolet rays can be used as a material for the inorganic insulating film 125f described later to achieve the same effect.

[0323] Furthermore, various inorganic insulating films can be used as the sacrificial film 158Rf and the mask film 159Rf, respectively. In particular, oxide insulating films are preferred because they have higher adhesion to the organic compound film 103Rf compared to nitride insulating films. For example, inorganic insulating materials such as aluminum oxide, hafnium oxide, and silicon oxide can be used as the sacrificial film 158Rf and the mask film 159Rf, respectively. For example, aluminum oxide films can be formed as the sacrificial film 158Rf and the mask film 159Rf using the ALD method. Using the ALD method is preferable because it reduces damage to the substrate (especially the organic compound layer).

[0324] For example, an inorganic insulating film (e.g., an aluminum oxide film) formed using the ALD method can be used as the sacrificial film 158Rf, and an inorganic film (e.g., an In-Ga-Zn oxide film, an aluminum film, or a tungsten film) formed using the sputtering method can be used as the mask film 159Rf.

[0325] Furthermore, the same inorganic insulating film can be used for both the sacrificial film 158Rf and the inorganic insulating layer 125 that is formed later. For example, an aluminum oxide film formed using the ALD method can be used for both the sacrificial film 158Rf and the inorganic insulating layer 125. Here, the same film formation conditions may be applied to the sacrificial film 158Rf and the inorganic insulating layer 125, or different film formation conditions may be applied to each. For example, by forming the sacrificial film 158Rf under the same conditions as the inorganic insulating layer 125, the sacrificial film 158Rf can be made into an insulating layer with high barrier properties against at least one of water and oxygen. On the other hand, since the sacrificial film 158Rf is a layer that will be mostly or completely removed in a later process, it is preferable that it be easy to process. For this reason, it is preferable to form the sacrificial film 158Rf under conditions where the substrate temperature during film formation is lower than that of the inorganic insulating layer 125.

[0326] Organic materials may be used for one or both of the sacrificial film 158Rf and the mask film 159Rf. For example, as the organic material, a material that is soluble in a solvent that is chemically stable to the film located at least on top of the organic compound film 103Rf may be used. Materials that are soluble in water or alcohol are particularly suitable. When forming such a film, it is preferable to apply the material by a wet film formation method while it is dissolved in a solvent such as water or alcohol, and then perform a heat treatment to evaporate the solvent. At this time, performing the heat treatment under a reduced pressure atmosphere is preferable because it allows the solvent to be removed at a low temperature and in a short time, thereby reducing thermal damage to the organic compound film 103Rf.

[0327] The sacrificial film 158Rf and the mask film 159Rf may be made of polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, alcohol-soluble polyamide resin, or organic resins such as perfluoropolymers.

[0328] For example, an organic film (e.g., a PVA film) formed using either a vapor deposition method or the wet film formation method described above can be used as the sacrificial film 158Rf, and an inorganic film (e.g., a silicon nitride film) formed using a sputtering method can be used as the mask film 159Rf.

[0329] Next, as shown in Figure 7A, a resist mask 190R is formed on the mask film 159Rf. The resist mask 190R can be formed by applying a photosensitive material (photoresist), followed by exposure and development.

[0330] The resist mask 190R may be made using either a positive-type resist material or a negative-type resist material.

[0331] The resist mask 190R is provided in a position that overlaps with the conductive layer 152R. Preferably, the resist mask 190R is also provided in a position that overlaps with the conductive layer 152C. This helps to suppress damage to the conductive layer 152C during the manufacturing process of the display device. It is not necessary to provide the resist mask 190R on the conductive layer 152C. Furthermore, it is preferable that the resist mask 190R be provided so as to cover from the edge of the organic compound film 103Rf to the edge of the conductive layer 152C (the edge on the organic compound film 103Rf side), as shown in the cross-sectional view between B1 and B2 in Figure 7A.

[0332] Next, as shown in Figure 7B, a portion 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. After that, the resist mask 190R is removed. Subsequently, the mask layer 159R is used as a mask (also called a hard mask) to remove a portion of the sacrificial film 158Rf to form a sacrificial layer 158R.

[0333] The sacrificial film 158Rf and the mask film 159Rf can be processed by wet etching or dry etching, respectively. It is preferable to process the sacrificial film 158Rf and the mask film 159Rf by isotropic etching.

[0334] By using the wet etching method, the damage to the organic compound film 103Rf during processing of the sacrificial film 158Rf and the mask film 159Rf can be reduced compared to using the dry etching method. When using the wet etching method, it is preferable to use chemical solutions such as a developer, an aqueous solution of tetramethylammonium hydroxide (TMAH), dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or a mixture thereof.

[0335] In the processing of the mask film 159Rf, the organic compound film 103Rf is not exposed, thus offering a wider range of processing method options compared to the processing of the sacrificial film 158Rf. Specifically, when processing the mask film 159Rf, even when using an etching gas containing oxygen, the degradation of the organic compound film 103Rf can be further suppressed.

[0336] Furthermore, when using a dry etching method for processing the sacrificial film 158Rf, the degradation of the organic compound film 103Rf can be suppressed by not using an oxygen-containing gas as the etching gas. When using a dry etching method, for example, CF ４ , C ４ F ８ SF ６ CHF ３ , Cl ２ , H ２ O, BCl ３ It is preferable to use a gas containing a Group 18 element such as He as the etching gas.

[0337] For example, when using an aluminum oxide film formed using the ALD method as the sacrificial film 158Rf, CHF ３ and He, or CHF ３ and He and CH ４ Using this method, a portion of the sacrificial film 158Rf can be removed by dry etching. Furthermore, when an In-Ga-Zn oxide film formed by sputtering is used as the mask film 159Rf, a portion of the mask film 159Rf can be removed by wet etching using diluted phosphoric acid. Alternatively, CH ４ A portion of the mask film 159Rf may be removed by dry etching using Ar. Alternatively, a portion of the mask film 159Rf can be removed by wet etching using diluted phosphoric acid. Furthermore, when a tungsten film formed by sputtering is used as the mask film 159Rf, SF ６ CF ４ and O ２ , or CF ４ and Cl ２ and O ２ Using this method, a portion of the mask film 159Rf can be removed by dry etching.

[0338] The resist mask 190R can be removed in the same manner as the resist mask 191. For example, it can be removed by ashing using oxygen plasma. Alternatively, oxygen gas and CF ４ , C ４ F ８ SF ６ CHF ３ , Cl ２ , H２ O, BCl ３ Alternatively, a Group 18 element such as He may be used. Or, the resist mask 190R may be removed by wet etching. In this case, since the sacrificial film 158Rf is located on the outermost surface and the organic compound film 103Rf is not exposed, damage to the organic compound film 103Rf can be suppressed during the resist mask 190R removal process. In addition, the range of selectable methods for removing the resist mask 190R can be broadened.

[0339] Next, as shown in Figure 7B, 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 to remove a portion of the organic compound film 103Rf and form the organic compound layer 103R.

[0340] As a result, as shown in Figure 7B, the laminated structure of the organic compound layer 103R, the sacrificial layer 158R, and the mask layer 159R remains on the conductive layer 152R. The conductive layers 152G and 152B are exposed.

[0341] Figure 7B shows an example where the edge of the organic compound layer 103R is located inside the edge of the conductive layer 152R. This configuration allows for pixel miniaturization, enabling the fabrication of high-resolution displays. Although not shown in Figure 7B, the etching process may result in the formation of recesses in areas of the insulating layer 175 that do not overlap with the organic compound layer 103R.

[0342] As described above, it is preferable that the resist mask 190R be provided so as to cover the area between the dashed-dotted lines B1 and B2, from the end of the organic compound layer 103R to the end of the conductive layer 152C (the end on the organic compound layer 103R side). As a result, as shown in Figure 7B, the sacrificial layer 158R and the mask layer 159R are provided so as to cover the area between the dashed-dotted lines B1 and B2, from the end of the organic compound layer 103R to the end of the conductive layer 152C (the end on the organic compound layer 103R side). Therefore, for example, exposure of the insulating layer 175 between the dashed-dotted lines B1 and B2 can be suppressed. This prevents the insulating layer 175, insulating layer 174, and a part of the insulating layer 173 from being removed by etching or the like, and prevents the conductive layer 179 from being exposed. Therefore, it is possible to suppress the conductive layer 179 from being unintentionally electrically connected to other conductive layers. For example, it is possible to suppress a short circuit between the conductive layer 179 and the common electrode 155 formed in a later process.

[0343] The organic compound film 103Rf is preferably processed by anisotropic etching. In particular, anisotropic dry etching is preferred. Alternatively, wet etching may be used.

[0344] When using the dry etching method, the degradation of the organic compound film 103Rf can be suppressed by not using an oxygen-containing gas as the etching gas.

[0345] Furthermore, an etching gas containing oxygen may be used. Including oxygen in the etching gas can increase the etching rate. Therefore, etching can be performed under low power conditions while maintaining a sufficiently fast etching rate. This suppresses damage to the organic compound film 103Rf. Moreover, it suppresses problems such as the adhesion of reaction products generated during etching.

[0346] When using the dry etching method, for example, H ２ CF ４ , C ４ F ８ SF ６ CHF ３ , Cl ２ , H ２ O, BCl ３It is preferable to use a gas containing one or more of the Group 18 elements such as He, Ar, etc., as the etching gas. Alternatively, it is preferable to use a gas containing one or more of these and oxygen as the etching gas. Alternatively, oxygen gas may be used as the etching gas. Specifically, for example, H ２ and Ar-containing gas, or CF ４ A gas containing He can be used as an etching gas. Also, for example, CF ４ Gases containing , He, and oxygen can be used as etching gases. Also, for example, H ２ Gases containing Ar and gases containing oxygen can be used as etching gases.

[0347] As described above, in one aspect of the present invention, a resist mask 190R is formed on a mask film 159Rf, and a mask layer 159R is formed by removing a portion of the mask film 159Rf using the resist mask 190R. Subsequently, an organic compound layer 103R is formed by removing a portion of the organic compound film 103Rf using the mask layer 159R as a hard mask. Thus, it can be said that an organic compound layer 103R is formed by processing the organic compound film 103Rf using a lithography method. Note that a portion of the organic compound film 103Rf may be removed using the resist mask 190R. Subsequently, the resist mask 190R may be removed.

[0348] Next, it is preferable to perform a hydrophobic treatment on the conductive layer 152G, for example. During processing of the organic compound film 103Rf, the surface state of the conductive layer 152G may change to hydrophilic. For example, by performing a hydrophobic treatment on the conductive layer 152G, the adhesion between the conductive layer 152G and the layer formed in a later process (in this case, the organic compound layer 103G) can be improved, and film peeling can be suppressed. However, the hydrophobic treatment is not required.

[0349] Next, as shown in Figure 8A, an organic compound film 103Gf, which will later become the organic compound layer 103G, is formed on the conductive layer 152G, the conductive layer 152B, the insulating layer 156R, the insulating layer 156G, the insulating layer 156B, the mask layer 159R, and the insulating layer 175.

[0350] The organic compound film 103Gf can be formed by the same method as that used to form the organic compound film 103Rf. Furthermore, the organic compound film 103Gf can have the same structure as the organic compound film 103Rf.

[0351] Next, as shown in Figure 8A, a sacrificial film 158Gf, which will later become a sacrificial layer 158G, and a mask film 159Gf, which will later become a mask layer 159G, are formed in order on the organic compound film 103Gf and the mask layer 159R, respectively. After that, a resist mask 190G is formed. The materials and formation methods for 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 for the resist mask 190G are the same as the conditions applicable to the resist mask 190R.

[0352] The resist mask 190G is placed in a position that overlaps with the conductive layer 152G.

[0353] Next, as shown in Figure 8B, a portion of the mask film 159Gf is removed using the resist mask 190G to form the mask layer 159G. The mask layer 159G remains on the conductive layer 152G. After that, the resist mask 190G is removed. Next, the mask layer 159G is used as a mask to remove a portion of the sacrificial film 158Gf to form the sacrificial layer 158G. Next, the organic compound film 103Gf is processed to form the organic compound layer 103G. For example, the mask layer 159G and the sacrificial layer 158G are used as a hard mask to remove a portion of the organic compound film 103Gf to form the organic compound layer 103G.

[0354] As a result, as shown in Figure 8B, the laminated structure of the organic compound layer 103G, the sacrificial layer 158G, and the mask layer 159G remains on the conductive layer 152G. The mask layer 159R and the conductive layer 152B are exposed.

[0355] Next, it is preferable to perform a hydrophobic treatment on the conductive layer 152B, for example. During processing of the organic compound film 103Gf, the surface state of the conductive layer 152B may change to hydrophilic. For example, by performing a hydrophobic treatment on the conductive layer 152B, the adhesion between the conductive layer 152B and the layer formed in a later process (in this case, the organic compound layer 103B) can be improved, and film peeling can be suppressed. However, the hydrophobic treatment is not required.

[0356] Next, as shown in Figure 8C, an organic compound film 103Bf, which will later become the organic compound layer 103B, is formed on the conductive layer 152B, the mask layer 159R, the insulating layer 156R, the insulating layer 156G, the insulating layer 156B, the mask layer 159G, and the insulating layer 175.

[0357] The organic compound film 103Bf can be formed by the same method as that used to form the organic compound film 103Rf. Furthermore, the organic compound film 103Bf can have the same configuration as the organic compound film 103Rf.

[0358] Next, as shown in Figure 8C, a sacrificial film 158Bf, which will later become a sacrificial layer 158B, and a mask film 159Bf, which will later become a mask layer 159B, are formed in order on the organic compound film 103Bf and the mask layer 159R, respectively. After that, a resist mask 190B is formed. The materials and formation methods for 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 for the resist mask 190B are the same as the conditions applicable to the resist mask 190R.

[0359] The resist mask 190B is placed in a position that overlaps with the conductive layer 152B.

[0360] Next, as shown in Figure 8D, a portion of the mask film 159Bf is removed using the resist mask 190B to form the mask layer 159B. The mask layer 159B remains on the conductive layer 152B. After that, the resist mask 190B is removed. Next, the mask layer 159B is used as a mask to remove a portion of the sacrificial film 158Bf to form the sacrificial layer 158B. Next, the organic compound film 103Bf is processed to form the organic compound layer 103B. For example, the mask layer 159B and the sacrificial layer 158B are used as a hard mask to remove a portion of the organic compound film 103Bf to form the organic compound layer 103B.

[0361] As a result, as shown in Figure 8D, the laminated 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 layers 159R and 159G are exposed.

[0362] Furthermore, it is preferable that the sides of the organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B are perpendicular or approximately perpendicular to the surface to be formed. For example, it is preferable that the angle between the surface to be formed and these sides be 60 degrees or more and 90 degrees or less.

[0363] As described above, the distance between two adjacent organic compound layers 103R, 103G, and 103B formed using lithography can be narrowed to 8 μm or less, 5 μm or less, 3 μm or less, 2 μm or less, or 1 μm or less. Here, this distance can be defined, for example, by the distance between two adjacent opposing ends of organic compound layers 103R, 103G, and 103B. By narrowing the distance between the island-shaped organic compound layers in this way, a display device with high resolution and a large aperture ratio can be provided. Furthermore, the distance between the first electrodes between adjacent light-emitting devices can also be narrowed, for example, to 10 μm or less, 8 μm or less, 5 μm or less, 3 μm or less, or 2 μm or less. It is preferable that the distance between the first electrodes between adjacent light-emitting devices is 2 μm or more and 5 μm or less.

[0364] Next, as shown in Figure 9A, it is preferable to remove the mask layer 159R, mask layer 159G, and mask layer 159B. Depending on subsequent processes, sacrificial layers 158R, 158G, 158B, mask layer 159R, mask layer 159G, and mask layer 159B may remain in the display device. By removing the mask layer 159R, mask layer 159G, and mask layer 159B at this stage, it is possible to suppress the remaining presence of the mask layer 159R, mask layer 159G, and mask layer 159B in the display device. For example, when conductive materials are used for the mask layer 159R, mask layer 159G, and mask layer 159B, removing the mask layer 159R, mask layer 159G, and mask layer 159B in advance can suppress the generation of leakage current and the formation of capacitance due to the remaining mask layer 159R, mask layer 159G, and mask layer 159B.

[0365] In this embodiment, the case in which mask layers 159R, 159G, and 159B are removed will be described as an example, but it is not necessary to remove mask layers 159R, 159G, and 159B. For example, if mask layers 159R, 159G, and 159B contain the aforementioned material that has light-shielding properties against ultraviolet rays, it is preferable to proceed to the next step without removing them, as this protects the organic compound layer from ultraviolet rays.

[0366] The same method as the mask film processing method can be used for the mask layer removal process. In particular, by using a wet etching method, the damage inflicted on the organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B when removing the mask layer can be reduced compared to when using a dry etching method.

[0367] Alternatively, the mask layer may be removed by dissolving it in a solvent such as water or alcohol. Examples of alcohols include ethyl alcohol, methyl alcohol, isopropyl alcohol (IPA), or glycerin.

[0368] After removing the mask layer, a drying treatment may be performed to remove water contained in the organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B, as well as water adsorbed on the surfaces of organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B. For example, a heat treatment can 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 to 200°C, preferably 60°C to 150°C, and more preferably 70°C to 120°C. A reduced-pressure atmosphere is preferable because it allows drying at a lower temperature.

[0369] Next, as shown in Figure 9B, an inorganic insulating film 125f, which will later become the inorganic insulating layer 125, is formed to cover the organic compound layer 103R, organic compound layer 103G, organic compound layer 103B, sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B.

[0370] As described later, an insulating film is formed in contact with the upper surface of the inorganic insulating film 125f, which will later become the insulating layer 127. For this reason, it is preferable that the upper surface of the inorganic insulating film 125f has a high affinity for the material used for the insulating film (for example, a photosensitive resin composition containing acrylic resin). To improve this affinity, it is preferable to hydrophobize (or increase the hydrophobicity of) the upper surface of the inorganic insulating film 125f by performing a surface treatment. For example, it is preferable to perform the treatment using a silylation agent such as hexamethyldisilazane (HMDS). By hydrophobizing the upper surface of the inorganic insulating film 125f in this way, the insulating film 127f can be formed with good adhesion. The aforementioned hydrophobic treatment may also be performed as the surface treatment.

[0371] Next, as shown in Figure 9C, an insulating film 127f, which will later become an insulating layer 127, is formed on the inorganic insulating film 125f.

[0372] The inorganic insulating film 125f and the insulating film 127f are preferably formed using a method that causes minimal damage to the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B. In particular, since the inorganic insulating film 125f is formed in contact with the side surfaces of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B, it is preferable that the inorganic insulating film 125f is formed using a method that causes less damage to the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B than the insulating film 127f.

[0373] Furthermore, the inorganic insulating film 125f and the insulating film 127f are formed at a temperature lower than the heat resistance temperature of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B, respectively. In addition, by increasing the substrate temperature during film formation of the inorganic insulating film 125f, it is possible to create a film with a low impurity concentration and high barrier properties against at least one of water and oxygen, even with a thin film thickness.

[0374] The substrate temperature when forming the inorganic insulating film 125f and the insulating film 127f is 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, respectively.

[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 using, for example, the ALD method. The ALD method is preferable because it can reduce film formation damage and allow for the formation of a film with high coverage. As the inorganic insulating film 125f, for example, it is preferable to form an aluminum oxide film using the ALD method.

[0377] In addition, the inorganic insulating film 125f may be formed using a sputtering method, CVD method, or PECVD method, which have a faster deposition rate than the ALD method. This allows for the production of highly reliable display devices with high productivity.

[0378] The insulating film 127f is preferably formed using the wet film formation method described above. The insulating film 127f is preferably formed using a photosensitive material, for example, by spin coating, and more specifically, it is preferably formed using a photosensitive resin composition containing an acrylic resin.

[0379] The insulating film 127f is preferably formed using a resin composition having, for example, a polymer, an acid generator, and a solvent. The polymer is formed using one or more monomers and has a structure in which one or more structural units (also called constituent units) are repeated regularly or irregularly. As the acid generator, one or both of the following can be used: a compound that generates acid upon irradiation with light, and a compound that generates acid upon heating. The resin composition may further contain one or more of the following: a photosensitive agent, a sensitizer, a catalyst, an adhesion aid, a surfactant, and an antioxidant.

[0380] Furthermore, it is preferable to perform a heat treatment (also called pre-baking) after the formation of the insulating film 127f. This heat treatment is performed at a temperature lower than the heat resistance temperature of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B. The substrate temperature during the heat treatment is preferably 50°C to 200°C, more preferably 60°C to 150°C, and even more preferably 70°C to 120°C. This allows for the removal of solvent contained in the insulating film 127f.

[0381] Next, exposure is performed to expose a portion of the insulating film 127f to visible light or ultraviolet light. Here, if a positive-type photosensitive resin composition containing acrylic resin is used for the insulating film 127f, visible light or ultraviolet light is irradiated to the area where the insulating layer 127 will not be formed in a later step. The insulating layer 127 is formed in the area sandwiched between any two of the conductive layers 152R, 152G, and 152B, and around the conductive layer 152C. Therefore, visible light or ultraviolet light is irradiated onto the conductive layer 152R, the conductive layer 152G, the conductive layer 152B, and the conductive layer 152C. If a negative-type photosensitive material is used for the insulating film 127f, visible light or ultraviolet light is irradiated to the area where the insulating layer 127 will be formed.

[0382] The width of the insulating layer 127 to be formed later can be controlled by the exposure area of ​​the insulating film 127f. In this embodiment, the insulating layer 127 is processed so that it has a portion that overlaps with the upper surface of the conductive layer 151.

[0383] The light used for exposure preferably includes the i-line (wavelength 365 nm). Furthermore, the light used for exposure may also include at least one of the g-line (wavelength 436 nm) and the h-line (wavelength 405 nm).

[0384] Here, by providing an oxygen barrier insulating layer (for example, an aluminum oxide film) as one or both of the sacrificial layer 158 (sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B) and the inorganic insulating film 125f, the diffusion of oxygen into the organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B can be reduced. When the organic compound layer is irradiated with light (visible light or ultraviolet light), the organic compounds contained in the organic compound layer may become excited, and their reaction with oxygen contained in the atmosphere may be promoted. More specifically, when light (visible light or ultraviolet light) is irradiated onto the organic compound layer in an oxygen-containing atmosphere, oxygen may bind to the organic compounds contained in the organic compound layer. By providing the sacrificial layer 158 and the inorganic insulating film 125f on an island-like organic compound layer, the binding of oxygen in the atmosphere to the organic compounds contained in the organic compound layer can be reduced.

[0385] Next, as shown in Figure 10A, development is performed to remove the exposed area of ​​the insulating film 127f and form an insulating layer 127a. The insulating layer 127a is formed in the region sandwiched between any two of the conductive layers 152R, 152G, and 152B, and in the region surrounding the conductive layer 152C. Here, when acrylic resin is used for the insulating film 127f, an alkaline solution can be used as the developer, for example, TMAH can be used.

[0386] Next, the residue (so-called scum) from the development process may be removed. For example, the residue can be removed by ashing using oxygen plasma.

[0387] Furthermore, etching may be performed to adjust the surface height of the insulating layer 127a. The insulating layer 127a may also be processed, for example, by ashing using oxygen plasma. In addition, even when a non-photosensitive material is used as the insulating film 127f, the surface height of the insulating film 127f can be adjusted, for example, by ashing.

[0388] Next, as shown in Figure 10B, etching is performed using the insulating layer 127a as a mask to remove a portion of the inorganic insulating film 125f. In this etching process, the film thickness of a portion of the sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B may be reduced. As a result, an inorganic insulating layer 125 is formed beneath the insulating layer 127a. In addition, a portion of the surface of the sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B is exposed. In the following, the etching process using the insulating layer 127a as a mask may be referred to as the first etching process.

[0389] The first etching process can be carried out by dry etching or wet etching. It is preferable that the inorganic insulating film 125f is deposited using the same material as the sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B, as this allows the first etching process to be performed in a single step.

[0390] By using the insulating layer 127a, which has a tapered side surface, as a mask for etching, the sides of the inorganic insulating layer 125, and the upper ends of the sides of the sacrificial layers 158R, 158G, and 158B can be made tapered relatively easily.

[0391] When performing dry etching, it is preferable to use a chlorine-based gas. Examples of chlorine-based gases include Cl ２ , BCl ３ SiCl ４ , and CCl ４ These can be used individually or in combination of two or more gases. In addition, oxygen gas, hydrogen gas, helium gas, and argon gas, etc., can be added to the chlorine-based gas as appropriate, individually or in combination of two or more gases. By using dry etching, the exposed areas of the sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B can be formed with good in-plane uniformity.

[0392] As the dry etching apparatus, a dry etching apparatus having a high-density plasma source can be used. A dry etching apparatus having a high-density plasma source can be, for example, an inductively coupled plasma (ICP) etching apparatus. Alternatively, a capacitively coupled plasma (CCP) etching apparatus having parallel plate electrodes can be used. The capacitively coupled plasma etching apparatus having parallel plate electrodes may be configured to apply a high-frequency voltage to one electrode of the parallel plate electrodes. Alternatively, it may be configured to apply multiple different high-frequency voltages to one electrode of the parallel plate electrodes. Alternatively, it may be configured to apply a high-frequency voltage of the same frequency to each of the parallel plate electrodes. Alternatively, it may be configured to apply high-frequency voltages of different frequencies to each of the parallel plate electrodes.

[0393] Furthermore, when dry etching is performed, by-products generated during dry etching may accumulate on the upper and side surfaces of the insulating layer 127a. As a result, components contained in the etching gas, components contained in the inorganic insulating film 125f, and components contained in the sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B may be present in the insulating layer 127 after the display device is completed.

[0394] Furthermore, it is preferable to perform the first etching process by wet etching. By using the wet etching method, damage to the organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B can be reduced compared to when the dry etching method is used. For example, wet etching can be performed using an alkaline solution. For example, TMAH, which is an alkaline solution, can be used for wet etching of an aluminum oxide film. In this case, wet etching can be performed using a paddle method. It is preferable that the inorganic insulating film 125f is formed using the same material as the sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B, as the above etching process can be performed in one step.

[0395] Furthermore, if the sacrificial layers 158R, 158G, and 158B are not completely removed in the first etching process, and the film thickness is reduced, the corresponding sacrificial layers 158R, 158G, and 158B will remain on the organic compound layers 103R, 103G, and 103B. Therefore, the processing time for subsequent steps can be shortened, and damage to the organic compound layers 103R, 103G, and 103B can be prevented.

[0396] Next, it is preferable to expose the entire substrate to visible light or ultraviolet light and irradiate the insulating layer 127a. The energy density of this exposure is 0 mJ / cm². ２ Even larger, 800 mJ / cm ２ The following is preferable: 0 mJ / cm ２ Larger, 500 mJ / cm ２ The following is more preferable: Performing such exposure after development may improve the transparency of the insulating layer 127a. In addition, it may be possible to lower the substrate temperature required for the heat treatment in a later process to deform the insulating layer 127a into a tapered shape.

[0397] Here, the presence of oxygen barrier insulating layers (e.g., an aluminum oxide film) as sacrificial layers 158R, 158G, and 158B reduces the diffusion of oxygen into organic compound layers 103R, 103G, and 103B. When an organic compound layer is irradiated with light (visible light or ultraviolet light), the organic compounds contained in the organic compound layer may become excited, and their reaction with oxygen in the atmosphere may be promoted. More specifically, when an organic compound layer is irradiated with light (visible light or ultraviolet light) in an oxygen-containing atmosphere, oxygen may bind to the organic compounds in the organic compound layer. By providing sacrificial layers 158R, 158G, and 158B on an island-like organic compound layer, the binding of oxygen in the atmosphere to the organic compounds contained in the organic compound layer can be reduced.

[0398] Next, a heat treatment (also called post-bake) is performed. By performing the heat treatment, the insulating layer 127a can be deformed into an insulating layer 127 having a tapered shape on its side surface (Figure 10C). This heat treatment is performed at a temperature lower than the heat resistance temperature of the organic compound layer. The heat treatment can be performed at a substrate temperature of 50°C to 200°C, preferably 60°C to 150°C, and more preferably 70°C to 130°C. The heating atmosphere may be an atmospheric atmosphere or an inert gas atmosphere. The heating atmosphere may also be an atmospheric pressure atmosphere or a reduced pressure atmosphere. It is preferable to use a higher substrate temperature for the heat treatment in this step than for the heat treatment after the formation of the insulating film 127f (pre-bake). This improves the adhesion between the insulating layer 127 and the inorganic insulating layer 125, and also improves the corrosion resistance of the insulating layer 127.

[0399] Furthermore, depending on the material of the insulating layer 127, as well as the post-bake temperature, time, and atmosphere, a concave curved shape may be formed on the side surface of the insulating layer 127. For example, the higher the temperature or the longer the post-bake time, the more likely the shape of the insulating layer 127 is to change, and a concave curved shape may be formed.

[0400] Next, as shown in Figure 11A, etching is performed using the insulating layer 127 as a mask to remove a portion of the sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B. In some cases, a portion of the inorganic insulating layer 125 may also be removed. As a result, openings are formed in the sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B, exposing the upper surfaces of the organic compound layer 103R, organic compound layer 103G, organic compound layer 103B, and conductive layer 152C. In the following, the etching process using the insulating layer 127 as a mask may be referred to as the second etching process.

[0401] The edges of the inorganic insulating layer 125 are covered with the insulating layer 127. Figure 11A also shows an example where the insulating layer 127 covers a portion of the edge of the sacrificial layer 158G (specifically, the tapered portion formed by the first etching process), while the tapered portion formed by the second etching process is exposed.

[0402] If the first etching process is omitted and the inorganic insulating layer 125 and sacrificial layer are etched together after post-bake, side etching may cause the inorganic insulating layer 125 and sacrificial layer beneath the edges of the insulating layer 127 to disappear, forming a cavity. This cavity can cause unevenness on the surface forming the common electrode 155, making it easier for the common electrode 155 to break down. Even if the inorganic insulating layer 125 and mask layer are side-etched and a cavity is formed in the first etching process, the insulating layer 127 can fill the cavity by performing post-bake afterward. Subsequently, in the second etching process, the mask layer is etched, resulting in less side etching and making it less likely for a cavity to form, or if a cavity does form, it can be made extremely small. As a result, the surface forming the common electrode 155 can be made flatter.

[0403] Furthermore, the insulating layer 127 may cover the entire edge of the sacrificial layer 158G. For example, the edge of the insulating layer 127 may droop and cover the edge of the sacrificial layer 158G. Also, for example, the edge of the insulating layer 127 may be in contact with at least one upper surface of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B. As mentioned above, if the insulating layer 127a is not exposed after development, the shape of the insulating layer 127 may change easily.

[0404] The second etching process is performed by wet etching. By using the wet etching method, damage to the organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B can be reduced compared to when using the dry etching method. Wet etching can be performed using an alkaline solution such as TMAH.

[0405] On the other hand, when performing a second etching process using a wet etching method, if there are gaps between the organic compound layer 103 and the sacrificial layer 158, between the organic compound layer 103 and the inorganic insulating layer 125, and at the interface between the organic compound layer 103 and the insulating layer 175 due to adhesion problems between the organic compound layer 103 and other layers, the chemical solution used in the second etching process may penetrate these gaps and come into contact with the pixel electrodes. If the chemical solution comes into contact with both the conductive layer 151 and the conductive layer 152, the conductive layer with the lower natural potential may be corroded by galvanic corrosion. For example, if aluminum is used as the conductive layer 151 and indium tin oxide is used as the conductive layer 152, the conductive layer 152 may be corroded. As a result, the yield of the display device may decrease. Furthermore, the reliability of the display device may decrease.

[0406] As described above, by forming the insulating layer 156 so as to cover the sides of the conductive layer 151 and the conductive layer 152, it is possible to prevent the inorganic insulating layer 125 from breaking off, and for example, in the second etching process, it is possible to prevent the chemical solution from coming into contact with the underlying structure such as the conductive layer 151. This prevents corrosion of the pixel electrodes.

[0407] As described above, by providing the insulating layer 127, the inorganic insulating layer 125, the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B, it is possible to suppress connection failures in the common electrode 155 between each light-emitting device due to the divided portion, and an increase in electrical resistance due to locally thin film thickness. As a result, the display device according to one embodiment of the present invention can improve the display quality.

[0408] Furthermore, after exposing a portion of the organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B, a further heat treatment is performed. This heat treatment can remove water contained in each organic compound layer, water adsorbed on the surface of each organic compound layer, etc. In addition, this heat treatment may change the shape of the insulating layer 127. Specifically, the insulating layer 127 may spread to cover at least one of the following: the edge of the inorganic insulating layer 125, the edge of the sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B, and the upper surface of the organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B.

[0409] If the temperature of the heat treatment is too low, it will not be possible to sufficiently remove water contained in each organic compound layer, water adsorbed on the surface of each organic compound layer, etc. Also, if the temperature of the heat treatment is too high, deterioration of the organic compound layer 103 and excessive changes in the shape of the insulating layer 127 may occur. Therefore, the heat treatment is preferably performed at a temperature higher than the temperature at which water desorbs from the organic compound layer 103, lower than the glass transition temperature of the organic compounds contained in the organic compound layer 103, and lower than the glass transition temperature of the organic compounds contained on the upper surface of the organic compound layer 103. Specifically, it is preferable to perform the treatment at a substrate temperature of 80°C to 130°C, preferably 90°C to 120°C, more preferably 100°C to 120°C, and even more preferably 100°C to 110°C. The heating atmosphere may be an atmospheric atmosphere or an inert gas atmosphere. The heating atmosphere may also be an atmospheric pressure atmosphere or a reduced pressure atmosphere, but a reduced pressure atmosphere is preferable in order to prevent the water desorbed from the organic compound layer 103 from being re-adsorbed.

[0410] This heat treatment effectively removes water contained in each organic compound layer, water adsorbed on the surface of each organic compound layer, without causing deterioration of the organic compound layer 103R, organic compound layer 103G, and organic compound layer 103B, or excessive changes in the shape of the insulating layer 127. This prevents a decrease in the characteristics of the light-emitting device.

[0411] Next, as shown in Figure 11B, a common layer 104 and a common electrode 155 are 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 layer 104 and the common electrode 155 can be formed by sputtering or vacuum deposition. The common layer 104 may be formed by deposition and the common electrode 155 by sputtering.

[0412] Next, as shown in Figure 11C, a protective layer 131 is formed on the common electrode 155. The protective layer 131 can be formed by methods such as vacuum deposition, sputtering, CVD, or ALD.

[0413] Next, the display device can be manufactured by bonding the substrate 120 onto the protective layer 131 using the resin layer 122. As described above, in one embodiment of the present invention, an insulating layer 156 is provided on the sides of the conductive layer 151 and the conductive layer 152. This increases the yield of the display device and suppresses the occurrence of defects.

[0414] As described above, in the method for manufacturing a display device according to one aspect of the present invention, the island-shaped organic compound layer 103R, the island-shaped organic compound layer 103G, and the organic compound layer 103B are formed not using a fine metal mask, but by processing after the film is deposited on one surface, so that the island-shaped layers can be formed with a uniform thickness. This makes it possible to realize a high-resolution display device or a display device with a high aperture ratio. Furthermore, even if the resolution or aperture ratio is high and the distance between subpixels is extremely short, it is possible to suppress contact between the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B in adjacent subpixels. Therefore, it is possible to suppress the generation of leakage current between subpixels. This makes it possible to prevent crosstalk and realize a display device with extremely high contrast. Moreover, even a display device having a tandem type light-emitting device manufactured using a lithography method can be provided with good characteristics.

[0415] The configuration of this embodiment can be used in appropriate combination with the configurations of other embodiments.

[0416] (Embodiment 4) In this embodiment, a light-emitting device according to one aspect of the present invention will be described with reference to Figures 12A to 12G and Figures 13A to 13I.

[0417] [Pixel Layout] In this embodiment, a pixel layout different from that shown in Figure 5A will be described. There are no particular limitations on the arrangement of subpixels, and various methods can be applied. Examples of subpixel arrangements include stripe arrangements, S-stripe arrangements, matrix arrangements, delta arrangements, Bayer arrangements, and pentile arrangements.

[0418] In this embodiment, the upper surface shape of the sub-pixel shown in the figure corresponds to the upper surface shape of the light-emitting region.

[0419] Examples of the top surface shape of a sub-pixel include polygons such as triangles, quadrilaterals (including rectangles and squares), pentagons, polygons with rounded corners, ellipses, or circles.

[0420] Furthermore, the circuit layout constituting the sub-pixel is not limited to the sub-pixel range shown in the figure, but may be arranged outside of it.

[0421] The pixel 178 shown in Figure 12A has an S-stripe array applied to it. The pixel 178 shown in Figure 12A is composed of three subpixels: subpixel 110R, subpixel 110G, and subpixel 110B.

[0422] The pixel 178 shown in Figure 12B includes a sub-pixel 110R having a roughly trapezoidal or triangular shape with rounded corners, a sub-pixel 110G having a roughly trapezoidal or triangular shape with rounded corners, and a sub-pixel 110B having a roughly square or hexagonal top surface shape with rounded corners. Furthermore, sub-pixel 110R has a larger light-emitting area than sub-pixel 110G. In this way, the shape and size of each sub-pixel can be determined independently. For example, the size of a sub-pixel can be reduced to a size that has a more reliable light-emitting device.

[0423] A pentile array is applied to pixels 124a and 124b shown in Figure 12C. Figure 12C shows an example in which pixels 124a having sub-pixels 110R and 110G and pixels 124b having sub-pixels 110G and 110B are arranged alternately.

[0424] Pixels 124a and 124b shown in Figures 12D to 12F utilize a delta array. Pixel 124a has two subpixels (subpixels 110R and 110G) in the top row (1st row) and one subpixel (subpixel 110B) in the bottom row (2nd row). Pixel 124b has one subpixel (subpixel 110B) in the top row (1st row) and two subpixels (subpixels 110R and 110G) in the bottom row (2nd row).

[0425] Figure 12D shows an example where each subpixel has a roughly square top shape with rounded corners, Figure 12E shows an example where each subpixel has a circular top shape, and Figure 12F shows an example where each subpixel has a roughly hexagonal top shape with rounded corners.

[0426] In Figure 12F, each subpixel is located inside a densely arranged hexagonal region. When focusing on one subpixel, it is arranged so that it is surrounded by six other subpixels. Furthermore, subpixels that emit light of the same color are not adjacent to each other. For example, when focusing on subpixel 110R, three subpixels 110G and three subpixels 110B are arranged alternately around it.

[0427] Figure 12G shows an example where the subpixels of each color are arranged in a zigzag pattern. Specifically, in a top view, the upper edges of two subpixels aligned in the row direction (for example, subpixel 110R and subpixel 110G, or subpixel 110G and subpixel 110B) are offset.

[0428] In each pixel shown in Figures 12A to 12G, it is preferable, for example, that sub-pixel 110R emits red light, sub-pixel 110G emits green light, and sub-pixel 110B emits blue light. However, the configuration of the sub-pixels is not limited to this, and the colors emitted by the sub-pixels and their order can be determined as appropriate. For example, sub-pixel 110G may emit red light, and sub-pixel 110R may emit green light.

[0429] In photolithography, the finer the pattern being processed, the more significant the effects of light diffraction become. This compromises the fidelity of transferring the photomask pattern through exposure, making it difficult to process the resist mask into the desired shape. Therefore, even if the photomask pattern is rectangular, patterns with rounded corners are likely to form. Consequently, the top surface shape of subpixels may be a polygon with rounded corners, an ellipse, or a circle.

[0430] Furthermore, in a method for manufacturing a light-emitting device according to one embodiment of the present invention, an organic compound layer is processed into an island shape using a resist mask. The resist film formed on the organic compound layer needs to be cured at a temperature lower than the heat resistance temperature of the organic compound layer. Therefore, depending on the heat resistance temperature of the organic compound layer material and the curing temperature of the resist material, the curing of the resist film may be insufficient. A resist film that is not sufficiently cured may take a shape that deviates from the desired shape during processing. As a result, the top surface shape of the organic compound layer may become a polygon with rounded corners, an ellipse, or a circle. For example, if an attempt is made to form a resist mask with a square top surface, a resist mask with a circular top surface may be formed, resulting in a circular top surface shape for the organic compound layer.

[0431] Furthermore, in order to achieve the desired shape of the upper surface of the organic compound layer, a technique (OPC (Optical Proximity Correction) technique) may be used to pre-correct the mask pattern so that the design pattern and the transferred pattern match. Specifically, in the OPC technique, for example, a correction pattern is added to the corners of the shape on the mask pattern.

[0432] As shown in Figures 13A to 13I, a pixel can be configured to have four types of subpixels.

[0433] The pixels 178 shown in Figures 13A to 13C are arranged in a stripe pattern.

[0434] Figure 13A shows an example where each subpixel has a rectangular top surface shape, Figure 13B shows an example where each subpixel has a top surface shape formed by connecting two semicircles and a rectangle, and Figure 13C shows an example where each subpixel has an elliptical top surface shape.

[0435] The pixels 178 shown in Figures 13D to 13F are subjected to a matrix arrangement.

[0436] Figure 13D shows an example where each subpixel has a square top surface shape, Figure 13E shows an example where each subpixel has a roughly square top surface shape with rounded corners, and Figure 13F shows an example where each subpixel has a circular top surface shape.

[0437] Figures 13G and 13H show an example in which one pixel 178 is composed of 2 rows and 3 columns.

[0438] Pixel 178, shown in Figure 13G, has three subpixels (subpixel 110R, subpixel 110G, and subpixel 110B) in the top row (1st row) and one subpixel (subpixel 110W) in the bottom row (2nd row). In other words, pixel 178 has subpixel 110R in the left column (1st column), subpixel 110G in the middle column (2nd column), subpixel 110B in the right column (3rd column), and subpixel 110W extending across these three columns.

[0439] The pixel 178 shown in Figure 13H has three subpixels (subpixel 110R, subpixel 110G, and subpixel 110B) in the top row (1st row) and three subpixels 110W in the bottom row (2nd row). In other words, the pixel 178 has subpixels 110R and 110W in the left column (1st column), subpixels 110G and 110W in the middle column (2nd column), and subpixels 110B and 110W in the right column (3rd column). As shown in Figure 13H, by aligning the arrangement of subpixels in the top row and the bottom row, it becomes possible to efficiently remove dust that may be generated during the manufacturing process, for example. Therefore, a light-emitting device with high display quality can be provided.

[0440] In the pixel 178 shown in Figures 13G and 13H, the layout of sub-pixels 110R, 110G, and 110B is in a stripe arrangement, which improves the display quality.

[0441] Figure 13I shows an example where one pixel 178 is composed of 3 rows and 2 columns.

[0442] Pixel 178, shown in Figure 13I, has a sub-pixel 110R in the top row (1st row), a sub-pixel 110G in the middle row (2nd row), a sub-pixel 110B spanning from the 1st to the 2nd row, and one sub-pixel (sub-pixel 110W) in the bottom row (3rd row). In other words, pixel 178 has sub-pixels 110R and 110G in the left column (1st column), a sub-pixel 110B in the right column (2nd column), and a sub-pixel 110W spanning these two columns.

[0443] In the pixel 178 shown in Figure 13I, the layout of sub-pixels 110R, 110G, and 110B is a so-called S-stripe arrangement, which improves the display quality.

[0444] The pixel 178 shown in Figures 13A to 13I is composed of four subpixels: subpixel 110R, subpixel 110G, subpixel 110B, and subpixel 110W. For example, subpixel 110R may be a subpixel that emits red light, subpixel 110G may be a subpixel that emits green light, subpixel 110B may be a subpixel that emits blue light, and subpixel 110W may be a subpixel that emits white light. At least one of subpixels 110R, 110G, 110B, and 110W may be a subpixel that emits cyan light, a subpixel that emits magenta light, a subpixel that emits yellow light, or a subpixel that emits near-infrared light.

[0445] As described above, the light-emitting device according to one aspect of the present invention can be configured to apply various layouts to pixels that consist of subpixels having light-emitting devices.

[0446] This embodiment can be appropriately combined with other embodiments or examples. Furthermore, if multiple configuration examples are shown within a single embodiment in this specification, these configuration examples can be appropriately combined.

[0447] (Embodiment 5) This embodiment describes a display device according to one aspect of the present invention.

[0448] The display device of this embodiment can be a high-definition display device. Therefore, the display device of this embodiment can be used, for example, as a display unit for information terminals (wearable devices) such as wristwatches and bracelets, as well as as a display unit for wearable devices that can be worn on the head, such as VR devices such as head-mounted displays (HMDs) and AR devices such as glasses.

[0449] Furthermore, the display device of this embodiment can be a high-resolution display device or a large-screen display device. Therefore, the display device of this embodiment can be used in electronic devices with relatively large screens, such as television equipment, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as in the display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game consoles, personal information terminals, and audio playback devices.

[0450] [Display Module] Figure 14A shows a perspective view of 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, but may be any of the display devices 100B to 100E described later.

[0451] The display module 280 has substrates 291 and 292. The display module 280 has a display unit 281. The display unit 281 is an area in the display module 280 that displays an image, and is an area in which light from each pixel provided in the pixel unit 284, which will be described later, can be seen.

[0452] Figure 14B shows a schematic perspective view illustrating the configuration of the substrate 291. On the substrate 291, a circuit section 282, a pixel circuit section 283 on the circuit section 282, and a pixel section 284 on the pixel circuit section 283 are stacked. In addition, a terminal section 285 for connecting to the FPC 290 is provided in the portion of the substrate 291 that does not overlap with the pixel section 284. The terminal section 285 and the circuit section 282 are electrically connected by a wiring section 286 composed of multiple wires.

[0453] The pixel section 284 has a plurality of pixels 284a arranged periodically. An enlarged view of one pixel 284a is shown on the right side of Figure 14B. Various configurations described in the previous embodiment can be applied to the pixels 284a.

[0454] The pixel circuit section 283 has a plurality of pixel circuits 283a arranged periodically.

[0455] One pixel circuit 283a is a circuit that controls the driving of multiple elements that a single pixel 284a has.

[0456] The circuit section 282 has circuits for driving each pixel circuit 283a of the pixel circuit section 283. For example, it is preferable to have one or both of a gate line drive circuit and a source line drive circuit. In addition, it may have at least one of the following: an arithmetic circuit, a memory circuit, and a power supply circuit.

[0457] The FPC 290 functions as wiring for supplying video signals or power potential, etc., to the circuit section 282 from an external source. An IC may also be mounted on the FPC 290.

[0458] Since the display module 280 can be configured such that one or both of the pixel circuit section 283 and the circuit section 282 are stacked on the lower side of the pixel section 284, the aperture ratio (effective display area ratio) of the display section 281 can be made extremely high.

[0459] Because such a display module 280 is extremely high-resolution, it can be suitably used in VR devices such as HMDs or AR devices in the form of glasses. For example, even in a configuration where the display part of the display module 280 is viewed through lenses, the display module 280 has an extremely high-resolution display part 281, so even when the display part is magnified with lenses, pixels are not visible, enabling a highly immersive display. Furthermore, the display module 280 is not limited to this and can be suitably used in electronic devices having relatively small display parts.

[0460] [Display device 100A] The display device 100A shown in Figure 15A 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.

[0461] The substrate 301 corresponds to the substrate 291 in Figures 14A and 14B. The transistor 310 is a transistor having a channel formation region in the substrate 301. As the substrate 301, a semiconductor substrate such as a single-crystal silicon substrate can be used. The transistor 310 has 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 functions as a gate electrode. The insulating layer 313 is located between the substrate 301 and the conductive layer 311 and functions as a gate insulating layer. The low-resistance region 312 is a region of the substrate 301 doped with impurities and functions as a source or drain. The insulating layer 314 is provided covering the side surface of the conductive layer 311.

[0462] Furthermore, an element isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301.

[0463] Furthermore, an insulating layer 261 is provided to cover the transistor 310, and a capacitance 240 is provided on the insulating layer 261.

[0464] The capacitor 240 has a conductive layer 241, a conductive layer 245, and an insulating layer 243 located between them. The conductive layer 241 functions as one electrode of the capacitor 240, the conductive layer 245 functions as the other electrode of the capacitor 240, and the insulating layer 243 functions as the dielectric of the capacitor 240.

[0465] The conductive layer 241 is provided on the insulating layer 261 and embedded in the insulating layer 254. The conductive layer 241 is electrically connected to either the source or drain of the transistor 310 by a plug 271 embedded in the insulating layer 261. The insulating layer 243 is provided covering the conductive layer 241. The conductive layer 245 is provided in the region that overlaps with the conductive layer 241 via the insulating layer 243.

[0466] An insulating layer 255 is provided covering the capacitance 240, an insulating layer 174 is provided on the insulating layer 255, and an insulating layer 175 is provided on the insulating layer 174. Light-emitting devices 130R, 130G, and 130B are provided on the insulating layer 175. An insulator is provided in the region between adjacent light-emitting devices.

[0467] An insulating layer 156R is provided so as to cover the side surface of the conductive layer 151R, an insulating layer 156G is provided so as to cover the side surface of the conductive layer 151G, and an insulating layer 156B is provided so as to cover the side surface of the conductive layer 151B. Furthermore, a conductive layer 152R is provided so as to cover the conductive layer 151R and the insulating layer 156R, a conductive layer 152G is provided so as to cover the conductive layer 151G and the insulating layer 156G, and a conductive layer 152B is provided 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.

[0468] The conductive layers 151R, 151G, and 151B are electrically connected to either the source or drain of the transistor 310 by the insulating layers 243, 255, 174, and plugs 256 embedded in the insulating layer 175, the conductive layer 241 embedded in the insulating layer 254, and plugs 271 embedded in the insulating layer 261. Various conductive materials can be used for the plugs.

[0469] Furthermore, a protective layer 131 is provided on the light-emitting devices 130R, 130G, and 130B. A substrate 120 is bonded to the protective layer 131 by a resin layer 122. Details of the components from the light-emitting devices 130 to the substrate 120 can be found in Embodiment 4. The substrate 120 corresponds to the substrate 292 in Figure 14A.

[0470] Figure 15B is a modified example of the display device 100A shown in Figure 15A. The display device shown in Figure 15B has a colored layer 132R, a colored layer 132G, and a colored layer 132B, and the light-emitting device 130 has a region that overlaps with one of the colored layers 132R, 132G, and 132B. In the display device shown in Figure 15B, the light-emitting device 130 can emit, for example, white light. Also, for example, the colored layer 132R can transmit red light, the colored layer 132G can transmit green light, and the colored layer 132B can transmit blue light.

[0471] [Display device 100B] Figure 16 shows a perspective view of the display device 100B, and Figure 17 shows a cross-sectional view of the display device 100C.

[0472] The display device 100B has a configuration in which substrate 352 and substrate 351 are bonded together. In Figure 16, substrate 352 is shown with a dashed line.

[0473] The display device 100B includes a pixel section 177, a connection section 140, a circuit 356, and wiring 355, etc. Figure 16 shows an example in which an IC 354 and an FPC 353 are mounted on the display device 100B. Therefore, the configuration shown in Figure 16 can also be called a display module having a display device 100B, an IC (integrated circuit), and an FPC. Here, a display module is a display device on which a connector such as an FPC is attached to the substrate, or on which an IC is mounted.

[0474] The connection portion 140 is provided on the outside of the pixel portion 177. There may be one or more connection portions 140. The connection portion 140 is electrically connected to the common electrode of the light-emitting device and the conductive layer, and can supply potential to the common electrode.

[0475] For example, a scan line drive circuit can be used as circuit 356.

[0476] The wiring 355 has the function of supplying signals and power to the pixel unit 177 and the circuit 356. These signals and power are input to the wiring 355 from an external source via the FPC 353 or from the IC 354.

[0477] Figure 16 shows an example in which IC 354 is provided on the substrate 351 using the COG (Chip On Glass) method or the COF (Chip On Film) method. IC 354 can be an IC having, for example, a scan line drive circuit or a signal line drive circuit. Note that the display device 100B and the display module may be configured without an IC. Alternatively, the IC may be mounted on the FPC, for example, using the COF method.

[0478] Figure 17 shows an example of a cross-section of the display device 100C, obtained by cutting off 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 Figure 16.

[0479] [Display device 100C] The display device 100C shown in Figure 17 has a transistor 201, a transistor 205, a light-emitting device 130R that emits red light, a light-emitting device 130G that emits green light, and a light-emitting device 130B that emits blue light, etc., between the substrate 351 and the substrate 352.

[0480] Details of the light-emitting devices 130R, 130G, and 130B can be found in Embodiment 4.

[0481] Light-emitting device 130R has a conductive layer 224R, a conductive layer 151R on the conductive layer 224R, and a conductive layer 152R on the conductive layer 151R. Light-emitting device 130G has a conductive layer 224G, a conductive layer 151G on the conductive layer 224G, and a conductive layer 152G on the conductive layer 151G. Light-emitting device 130B has a conductive layer 224B, a conductive layer 151B on the conductive layer 224B, and a conductive layer 152B on the conductive layer 151B.

[0482] The conductive layer 224R is connected to the conductive layer 222b of the transistor 205 through an opening provided in the insulating layer 214. The end of the conductive layer 151R is located outside the end of the conductive layer 224R. The insulating layer 156R is provided so as to have a region in contact with the 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.

[0483] The conductive layers 224G, 151G, 152G, and insulating layer 156G in the light-emitting device 130G, and the conductive layers 224B, 151B, 152B, and insulating layer 156B in the light-emitting device 130B are the same as the conductive layers 224R, 151R, 152R, and insulating layer 156R in the light-emitting device 130R, so a detailed explanation is omitted.

[0484] The conductive layer 224R, conductive layer 224G, and conductive layer 224B have recesses formed to cover the openings provided in the insulating layer 214. Layer 128 is embedded in these recesses.

[0485] Layer 128 has the function of filling and flattening the recesses of conductive layers 224R, 224G, and 224B. Conductive layers 151R, 151G, and 151B are provided on conductive layers 224R, 224G, and 224B and on layer 128, and are electrically connected to conductive layers 224R, 224G, and 224B. Therefore, regions overlapping with the recesses of conductive layers 224R, 224G, and 224B can also be used as light-emitting regions, thereby increasing the aperture ratio of the pixels.

[0486] Layer 128 may be an insulating layer or a conductive layer. Various inorganic insulating materials, organic insulating materials, and conductive materials can be used for layer 128 as appropriate. In particular, it is preferable that layer 128 be formed using an insulating material, and especially preferable that it be formed using an organic insulating material. For example, an organic insulating material that can be used for the insulating layer 127 described above can be applied to layer 128.

[0487] A protective layer 131 is provided on the light-emitting devices 130R, 130G, and 130B. The protective layer 131 and the substrate 352 are bonded via an adhesive layer 142. A light-shielding layer 157 is provided on the substrate 352. A solid sealing structure or a hollow sealing structure can be applied to seal the light-emitting devices 130. In Figure 17, the space between the substrate 352 and the substrate 351 is filled with the adhesive layer 142, indicating a solid sealing structure. Alternatively, the space may be filled with an inert gas (such as nitrogen or argon), indicating a hollow sealing structure. In this case, the adhesive layer 142 may be provided so as not to overlap with the light-emitting devices. Furthermore, the space may be filled with a resin different from the adhesive layer 142, which is provided in a frame shape.

[0488] Figure 17 shows an example in which the connection portion 140 has a conductive layer 224C obtained by processing the same conductive film as conductive layers 224R, 224G, and 224B; a conductive layer 151C obtained by processing the same conductive film as conductive layers 151R, 151G, and 151B; and a conductive layer 152C obtained by processing the same conductive film as conductive layers 152R, 152G, and 152B. Figure 17 also shows an example in which an insulating layer 156C is provided so as to cover the side surface of conductive layer 151C.

[0489] The display device 100C is a top-emission type. The light emitted by the light-emitting device is emitted towards the substrate 352. It is preferable to use a material with high transmittance to visible light for the substrate 352. The pixel electrodes contain a material that reflects visible light, and the counter electrodes (common electrodes 155) contain a material that transmits visible light.

[0490] On the substrate 351, insulating layers 211, 213, 215, and 214 are provided in this order. A portion of insulating layer 211 functions as a gate insulating layer for each transistor. A portion of insulating layer 213 functions as a gate insulating layer for each transistor. Insulating layer 215 is provided covering the transistors. Insulating layer 214 is provided covering the transistors and functions as a planarization layer. The number of gate insulating layers and insulating layers covering the transistors are not limited and may be a single layer or two or more layers, respectively.

[0491] It is preferable to use an inorganic insulating film as the insulating layer 211, insulating layer 213, and insulating layer 215.

[0492] An organic insulating layer is preferred for the insulating layer 214, which functions as a planarizing layer.

[0493] Transistors 201 and 205 have a conductive layer 221 that functions as a gate, an insulating layer 211 that functions as a gate insulating layer, conductive layers 222a and 222b that function as source and drain, a semiconductor layer 231, an insulating layer 213 that functions as a gate insulating layer, and a conductive layer 223 that functions as a gate.

[0494] A connection portion 204 is provided in the region of substrate 351 where substrate 352 does not overlap. At the connection portion 204, the source electrode or drain electrode of transistor 201 is electrically connected to FPC 353 via conductive layer 166 and connection layer 242. The conductive layer 166 is shown as an example of a laminated structure consisting of a conductive film obtained by processing the same conductive film as conductive layers 224R, 224G, and 224B, a conductive film obtained by processing the same conductive film as conductive layers 151R, 151G, and 151B, and a conductive film obtained by processing the same conductive film as conductive layers 152R, 152G, and 152B. On the upper surface of the connection portion 204, the conductive layer 166 is exposed. This allows the connection portion 204 and FPC 353 to be electrically connected via the connection layer 242.

[0495] It is preferable to provide a light-shielding layer 157 on the surface of the substrate 352 that faces the substrate 351. The light-shielding layer 157 can be provided between adjacent light-emitting devices, at connection points 140, and in circuits 356, etc. Various optical components can also be arranged on the outside of the substrate 352.

[0496] Materials suitable for use on substrate 120 can be applied to substrate 351 and substrate 352, respectively.

[0497] As the adhesive layer 142, a material that can be used for the resin layer 122 can be applied.

[0498] As the connecting layer 242, an anisotropic conductive film (ACF) or an anisotropic conductive paste (ACP) can be used.

[0499] [Display device 100D] The display device 100D shown in Figure 18 differs from the display device 100C shown in Figure 17 mainly in that it is a bottom-emission type display device.

[0500] The light emitted by the light-emitting device is emitted towards the substrate 351. It is preferable to use a material with high transmittance to visible light for the substrate 351. On the other hand, the light transmittance of the material used for the substrate 352 is not a requirement.

[0501] It is preferable to form a light-shielding layer 317 between the substrate 351 and the transistor 201, and between the substrate 351 and the transistor 205. Figure 18 shows an example 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.

[0502] 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.

[0503] 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.

[0504] The conductive layers 112R, 112B, 126R, 126B, 129R, and 129B are made of materials with high transmittance to visible light. It is preferable to use a material that reflects visible light for the second electrode 102.

[0505] Although the light-emitting device 130G is not shown in Figure 18, it is also provided.

[0506] Furthermore, while Figure 18 and others show an example where the upper surface of layer 128 has a flat portion, the shape of layer 128 is not particularly limited.

[0507] [Display Device 100D2] The display device 100D2 shown in Figure 19A is an example of a bottom-emission type display device, different from the display device 100D shown in Figure 18. The display device 100D2 differs from the display device 100D in that it has an organic resin layer 180. Note that in the figure, the reference numerals for components that are the same as in Figure 18 may be omitted, and details can be found in the description in Figure 18.

[0508] Furthermore, Figure 19B shows the top view layout of a pixel 178 (pixels 178a and 178b) having sub-pixels 110 (sub-pixels 110R, 110G, 110B, and 110W), and Figure 19C shows the top view of the organic resin layer 180 in the region where sub-pixels 110R and 110W of pixel 178 are formed. The space between the light-shielding layers 317 is the width 110Rw of the light-emitting region of sub-pixel 110R.

[0509] As shown in Figure 19A, the organic resin layer 180 is provided on the insulating layer 214. As shown in the region enclosed by the dashed line in Figure 19A and in Figure 19C, the organic resin layer 180 has curved recesses 181 (recesses 181a and 181b) in at least the region where subpixels are formed. The recesses 181 may also be provided outside the light-emitting region, such as recess 181c. By providing recess 181c, the light emitted in the region overlapping with the light-shielding layer 317 or the light that has traveled to the region overlapping with the light-shielding layer 317 can be refracted and extracted from the light-emitting region, thereby improving the luminous efficiency.

[0510] Multiple recesses 181 may be formed in a matrix. Recesses 181a and 181b may be in contact with each other, or they may have a flat surface between them.

[0511] Furthermore, in Figure 19, the upper surface shape of the recess is shown as a hexagon (Figure 19C) and the cross-sectional shape as a semicircle (Figure 19A), but other shapes may be used as needed. For example, the upper surface shape of the recess may be a triangle, a quadrilateral (including rectangles and squares), a pentagon or other polygon, a polygon with rounded corners, an ellipse, or a circle.

[0512] As the organic resin layer 180, an insulating layer having an organic material can be used. For example, as the organic resin layer 180, acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimidoamide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins can be used. Alternatively, as the organic resin layer 180, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin may be used.

[0513] Furthermore, a photosensitive resin can be used as the organic resin layer 180. A photoresist may be used as the photosensitive resin. The photosensitive resin can be a positive-type material or a negative-type material.

[0514] The organic resin layer 180 may 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, a resin that can be used as a color filter that transmits red, blue, or green light and absorbs other light, or a resin that contains carbon black as a pigment and functions as a black matrix can be used.

[0515] Furthermore, the organic resin layer 180 has a first electrode 101 (first electrode 101R and first electrode 101W), and the first electrode 101 has an organic compound layer 103. The ends of the first electrode 101 and the organic compound layer 103 may be covered with an insulating layer 127.

[0516] Furthermore, the first electrode 101, formed on the organic resin layer 180, has recesses along with the recesses of the organic resin layer 180. Additionally, the organic compound layer 103, formed on the first electrode 101, has recesses along with the recesses of the first electrode 101. Furthermore, the common layer 104, formed on the organic compound layer 103, has recesses along with the recesses of the organic compound layer 103. Finally, the second electrode 102, formed on the common layer 104, has recesses along with the recesses 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 have a structure in which they overlap each other.

[0517] Furthermore, 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 the structure is bonded to the substrate 352 via an adhesive layer 142.

[0518] Although the light-emitting devices 130G and 130B are not shown in Figure 19, they are also provided.

[0519] [Display device 100E] The display device 100E shown in Figure 20 is a modified version of the display device 100C shown in Figure 17, and differs from the display device 100C mainly in that it has a colored layer 132R, a colored layer 132G, and a colored layer 132B.

[0520] In the display device 100E, the light-emitting device 130 has a region that overlaps with one of the colored layers 132R, 132G, and 132B. The colored layers 132R, 132G, and 132B can be provided on the substrate 351 side of the substrate 352. The edges of the colored layer 132R, the edges of the colored layer 132G, and the edges of the colored layer 132B can overlap with the light-shielding layer 157.

[0521] In the display device 100E, the light-emitting device 130 can emit, for example, white light. Also, for example, the colored layer 132R can transmit red light, the colored layer 132G can transmit green light, and the colored layer 132B can transmit blue light. The display device 100E may also be configured to have the colored layers 132R, 132G, and 132B placed between the protective layer 131 and the adhesive layer 142.

[0522] [Display device 100E2] The display device 100E2 shown in Figure 21A is a modified version of the display device 100E shown in Figure 20, and has a microlens 182 on the colored layer 132R, the colored layer 132G, and the colored layer 132B. Note that in the figure, the reference numerals for components that are the same as in Figure 20 may be omitted, and details can be found in the description in Figure 20.

[0523] Figure 21B shows the top view layout of a pixel 178 (pixels 178a and 178b) having sub-pixels 110 (sub-pixels 110R, 110G, and 110B), and Figure 21C shows the top view of the microlens 182 in the region where the sub-pixels 110R and 110G of pixel 178 are formed. The region where the common electrode 155 and the organic compound layer 103 are in contact is the width 110Gw of the light-emitting region of sub-pixel 110G.

[0524] The display device 100E2 shown in Figure 21A has a planarization film 143 on a protective layer 131, and a colored layer 132R, a colored layer 132G, and a colored layer 132B on the planarization film 143. A planarization film 144 is provided so as to cover the colored layers 132R, 132G, and 132B. A microlens 182 is provided on the planarization film 144.

[0525] Furthermore, as shown in Figure 21C, the microlenses 182 may be provided for each sub-pixel in the region where the sub-pixels are formed.

[0526] In Figure 21C, the top surface shape of the microlens 182 is shown as a hexagon, but other shapes may be used as needed. For example, the top surface shape of the recess may be a triangle, a quadrilateral (including rectangles and squares), a pentagon, or other polygons, a polygon with rounded corners, an ellipse, or a circle.

[0527] The microlens 182 can be formed using the same material as the organic resin layer 180.

[0528] This embodiment can be appropriately combined with other embodiments or examples. Furthermore, if multiple configuration examples are shown within a single embodiment in this specification, these configuration examples can be appropriately combined.

[0529] (Embodiment 6) This embodiment describes an electronic device according to one aspect of the present invention.

[0530] The electronic device of this embodiment has a light-emitting device according to one aspect of the present invention in its display unit. The light-emitting device according to one aspect of the present invention is highly reliable and can be easily made high-definition and high-resolution. Therefore, it can be used in the display units of various electronic devices.

[0531] Examples of electronic devices include television sets, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, and other electronic devices with relatively large screens, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game consoles, personal digital assistants, and audio playback devices.

[0532] In particular, since the light-emitting device according to one aspect of the present invention can increase resolution, it can be suitably used in electronic devices having a relatively small display area. Examples of such electronic devices include wristwatch-type and bracelet-type information terminals (wearable devices), as well as wearable devices that can be attached to the head, such as VR devices such as head-mounted displays, AR devices such as glasses, and MR (Mixed Reality) devices.

[0533] A light-emitting device according to one aspect of the present invention preferably has an extremely high resolution such as HD (1280 x 720 pixels), FHD (1920 x 1080 pixels), WQHD (2560 x 1440 pixels), WQXGA (2560 x 1600 pixels), 4K (3840 x 2160 pixels), or 8K (7680 x 4320 pixels). In particular, a resolution of 4K, 8K, or higher is preferred. Furthermore, the pixel density (resolution) of the light-emitting device according to one aspect of the present invention is preferably 100 ppi or more, preferably 300 ppi or more, more preferably 500 ppi or more, more preferably 1000 ppi or more, more preferably 2000 ppi or more, more preferably 3000 ppi or more, more preferably 5000 ppi or more, and even more preferably 7000 ppi or more. By using a light-emitting device having high resolution and / or high detail, it is possible to further enhance the sense of presence and depth. Furthermore, there are no particular limitations on the aspect ratio of the light-emitting device according to one embodiment of the present invention. For example, the light-emitting device can accommodate various aspect ratios such as 1:1 (square), 4:3, 16:9, and 16:10.

[0534] The electronic device of this embodiment may have sensors (including those with functions to measure force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation).

[0535] The electronic device of this embodiment can have a variety of functions. For example, it can have a function to display various information (still images, videos, text images, etc.) on the display unit, a touch panel function, a function to display a calendar, date or time, a function to execute various software (programs), a wireless communication function, a function to read programs or data recorded on a recording medium, and so on.

[0536] Figures 22A to 22D illustrate an example of a wearable device that can be worn on the head. These wearable devices have at least one of the following functions: a function to display AR content, a function to display VR content, a function to display SR (Substantial Reality) content, and a function to display MR content. By having an electronic device that has the function to display at least one of the following content types, such as AR, VR, SR, and MR, it is possible to enhance the user's sense of immersion.

[0537] The electronic device 700A shown in Figure 22A and the electronic device 700B shown in Figure 22B each include a pair of display panels 751, a pair of housings 721, a communication unit (not shown), a pair of mounting units 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.

[0538] A light-emitting device according to one embodiment of the present invention can be applied to the display panel 751. Therefore, a highly reliable electronic device can be made.

[0539] Electronic devices 700A and 700B can project an image displayed on the display panel 751 onto the display area 756 of the optical element 753. Because the optical element 753 is translucent, the user can see the image displayed on the display area superimposed on the transmitted image visible through the optical element 753. Therefore, electronic devices 700A and 700B are electronic devices capable of AR display.

[0540] Electronic devices 700A and 700B may be equipped with cameras capable of capturing images of the area in front of them as imaging units. Furthermore, electronic devices 700A and 700B may each be equipped with acceleration sensors such as gyro sensors to detect the orientation of the user's head and display an image corresponding to that orientation in the display area 756.

[0541] The communications unit has a wireless communication device, which can supply, for example, a video signal. Alternatively, instead of the wireless communication device, or in addition to the wireless communication device, it may be equipped with a connector to which a cable for supplying video signals and power potential can be connected.

[0542] Furthermore, electronic devices 700A and 700B are equipped with batteries (not shown) that can be charged wirelessly, wired, or both.

[0543] The housing 721 may be equipped with a touch sensor module. The touch sensor module has the function of detecting when the outer surface of the housing 721 is touched. The touch sensor module can detect the user's tap or slide operations and perform various processes. For example, a tap operation can be used to pause or resume the video, and a slide operation can be used to fast forward or rewind. Furthermore, by providing a touch sensor module in each of the two housings 721, the range of operations can be expanded.

[0544] Various types of touch sensors can be used in the touch sensor module. For example, various methods such as capacitive, resistive, infrared, electromagnetic induction, surface acoustic wave, or optical sensors can be employed. In particular, it is preferable to apply capacitive or optical sensors to the touch sensor module.

[0545] When using an optical touch sensor, a photoelectric conversion device (also called a photoelectric conversion element) can be used as the light-receiving element. The active layer of the photoelectric conversion device can be made of either an inorganic semiconductor or an organic semiconductor, or both.

[0546] The electronic device 800A shown in Figure 22C and the electronic device 800B shown in Figure 22D each 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.

[0547] A light-emitting device according to one embodiment of the present invention can be applied to the display unit 820. Therefore, a highly reliable electronic device can be made.

[0548] The display unit 820 is located inside the housing 821 in a position visible through the lens 832. Furthermore, by displaying different images on a pair of display units 820, a three-dimensional display using parallax can be achieved.

[0549] Electronic devices 800A and 800B can each be described as electronic devices for VR. A user wearing electronic device 800A or electronic device 800B can view the image displayed on the display unit 820 through the lens 832.

[0550] It is preferable that electronic devices 800A and 800B each have a mechanism that allows adjustment of the left and right positions of the lens 832 and the display unit 820 so that they are in the optimal position according to the user's eye position. It is also preferable that they have a mechanism that adjusts the focus by changing the distance between the lens 832 and the display unit 820.

[0551] The attachment portion 823 allows the user to attach the electronic device 800A or 800B to their head. Note that, for example, in Figure 22C, it is illustrated as having a shape similar to the temples (or arms, etc.) of eyeglasses, but it is not limited to this. The attachment portion 823 only needs to be wearable by the user; for example, it may be helmet-shaped or band-shaped.

[0552] The imaging unit 825 has the 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. In addition, multiple cameras may be provided to accommodate multiple angles of view, such as telephoto and wide-angle.

[0553] Although an example with an imaging unit 825 is shown here, any distance measuring sensor (hereinafter also referred to as a detection unit) capable of measuring the distance to an object can be provided. In other words, the imaging unit 825 is one form of the detection unit. As the detection unit, for example, an image sensor or a distance image sensor such as LiDAR (Light Detection and Ranging) can be used. By using the image obtained by the camera and the image obtained by the distance image sensor, more information can be acquired, enabling more accurate gesture control.

[0554] The electronic device 800A may have a vibration mechanism that functions as a bone conduction earphone. For example, a configuration having such a vibration mechanism can be applied to one or more of the display unit 820, housing 821, and mounting unit 823. This eliminates the need for separate audio equipment such as headphones, earphones, or speakers, allowing users to enjoy video and audio simply by wearing the electronic device 800A.

[0555] Electronic devices 800A and 800B may each have input terminals. Cables can be connected to the input terminals to supply video signals from video output devices, etc., and power for charging batteries provided in the electronic devices.

[0556] An electronic device according to one aspect of the present invention may have a function for wireless communication with an earphone 750. The earphone 750 has a communication unit (not shown) and has a wireless communication function. The earphone 750 can receive information (e.g., voice data) from the electronic device through its wireless communication function. For example, the electronic device 700A shown in Figure 22A has a function for transmitting information to the earphone 750 through its wireless communication function. Also, for example, the electronic device 800A shown in Figure 22C has a function for transmitting information to the earphone 750 through its wireless communication function.

[0557] Furthermore, the electronic device may have an earphone section. The electronic device 700B shown in Figure 22B has an earphone section 727. For example, the earphone section 727 and the control unit can be connected to each other by a wire. Part of the wiring connecting the earphone section 727 and the control unit may be located inside the housing 721 or the mounting section 723.

[0558] Similarly, the electronic device 800B shown in Figure 22D has an earphone unit 827. For example, the earphone unit 827 and the control unit 824 can be connected to each other by a wire. Part of the wiring connecting the earphone unit 827 and the control unit 824 may be located inside the housing 821 or the mounting unit 823. Also, the earphone unit 827 and the mounting unit 823 may have magnets. This allows the earphone unit 827 to be fixed to the mounting unit 823 by magnetic force, making storage easier and preferable.

[0559] Furthermore, the electronic device may have an audio output terminal to which earphones or headphones can be connected. The electronic device may also have an audio input terminal and / or an audio input mechanism. For example, a microphone or other sound-collecting device can be used as the audio input mechanism. By having an audio input mechanism, the electronic device may be given the function of a so-called headset.

[0560] Thus, as one embodiment of the present invention, both eyeglass-type (electronic devices 700A and 700B, etc.) and goggle-type (electronic devices 800A and 800B, etc.) are preferred as electronic devices.

[0561] Furthermore, an electronic device according to one aspect of the present invention can transmit information to earphones via wired or wireless means.

[0562] The electronic device 6500 shown in Figure 23A is a portable information terminal that can be used as a smartphone.

[0563] 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, and a light source 6508, etc. The display unit 6502 has a touch panel function.

[0564] A light-emitting device according to one embodiment of the present invention can be applied to the display unit 6502. Therefore, a highly reliable electronic device can be made.

[0565] Figure 23B is a schematic cross-sectional view of the housing 6501 including the end on the microphone 6506 side.

[0566] A light-transmitting protective member 6510 is provided on the display side of the housing 6501, and the display panel 6511, optical member 6512, touch sensor panel 6513, printed circuit board 6517, and battery 6518 are arranged in the space enclosed by the housing 6501 and the protective member 6510.

[0567] The protective member 6510 is fixed to the display panel 6511, the optical member 6512, and the touch sensor panel 6513 by an adhesive layer (not shown).

[0568] In the area outside the display unit 6502, a portion of the display panel 6511 is folded back, and the FPC 6515 is connected to this folded portion. IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to terminals provided on the printed circuit board 6517.

[0569] A light-emitting device according to one embodiment of the present invention can be applied to the display panel 6511. This makes it possible to realize an extremely lightweight electronic device. Furthermore, because the display panel 6511 is extremely thin, it is possible to incorporate a large-capacity battery 6518 while keeping the thickness of the electronic device low. In addition, by folding back a part of the display panel 6511 and placing the connection part with the FPC 6515 on the back of the pixel section, an electronic device with a narrow bezel can be realized.

[0570] Figure 23C shows an example of a television system. The television system 7100 has a display unit 7000 incorporated into a housing 7171. Here, the housing 7171 is shown to be supported by a stand 7173.

[0571] A light-emitting device according to one embodiment of the present invention can be applied to the display unit 7000. Therefore, a highly reliable electronic device can be made.

[0572] The television device 7100 shown in Figure 23C can be operated using the operation switches on the housing 7171 and a separate remote control unit 7151. Alternatively, the display unit 7000 may be equipped with a touch sensor, and the television device 7100 can be operated by touching the display unit 7000 with a finger or the like. The remote control unit 7151 may ha...

Claims

An organic compound represented by the general formula (G1). (In the formula, A represents a substituted or unsubstituted spirobifluorenyl group, R １ ~R ５ (This represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, with at least one representing a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms.) An organic compound represented by the general formula (G2). (In the formula, R １ ~R ５ R represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one represents a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms. ６ ~R ８ (This represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, with at least one representing a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms.) An organic compound represented by the general formula (G1). (In the formula, A represents a substituted or unsubstituted spirobifluorenyl group, and R １ to R ５ each represents either hydrogen (including deuterium), a linear alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one represents a linear alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms. The organic compound represented by the general formula (G1) has a plurality of hydrocarbon groups selected from a linear alkyl group having 3 to 6 carbon atoms and a cyclic alkyl group having 3 to 10 carbon atoms, and the ratio of the total number of carbon atoms forming bonds with sp ３ hybrid orbitals to the total number of carbon atoms in the molecule is 10% or more and 50% or less.) An organic compound represented by the general formula (G2). (In the formula, R １ ~R ５ R represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, and at least one represents a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms. ６ ~R ８ The group represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, with at least one representing a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms. The organic compound represented by the above general formula (G2) has multiple hydrocarbon groups selected from chain alkyl groups having 3 to 6 carbon atoms and cyclic alkyl groups having 3 to 10 carbon atoms, and the sp relative to the total number of carbon atoms in the molecule ３ The proportion of total carbon atoms forming bonds in hybrid orbitals is between 10% and 50%. 　 An organic compound represented by structural formula (100) or structural formula (105). An organic compound represented by the general formula (g1). (In the formula, X represents a halogen, R １ ~R ５ (This represents hydrogen (including deuterium), a chain alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms, with at least one representing a chain alkyl group having 3 to 7 carbon atoms or a cyclic alkyl group having 3 to 10 carbon atoms.) An organic compound represented by the general formula (g2). (In the formula, X represents a halogen, R ２ and R ４ Each of these independently represents either a chain-type alkyl group having 3 to 7 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms. An organic compound represented by structural formula (200).

Images