Light-emitting devices, display devices, light-emitting apparatus, electronic equipment and lighting apparatus

Abstract

To provide light-emitting devices with high luminous efficiency. [Solution] Between the first electrode and the second electrode, It has an EL layer located at, and the EL layer comprises at least an emissive layer, a first layer, and a second It has a layer and a third layer, and the first layer is positioned between the first electrode and the light-emitting layer. The third layer is positioned between the first layer and the light-emitting layer, and the second layer is , located between the first layer and the third layer, the first layer is a first organic compound The second layer contains a second organic compound, and the third layer contains a third organic compound. The second organic compound includes, and the parametric refractive index of the first organic compound is equal to the parametric refractive index of the first organic compound. This is a light-emitting device with a refractive index higher than that of the third organic compound mentioned above.

Description

[Technical Field]

[0001] One aspect of the present invention relates to an organic compound, a light-emitting element, a light-emitting device, a display module, and lighting. This relates to lighting modules, display devices, light-emitting devices, electronic equipment, lighting devices, and electronic devices. Furthermore, one aspect of the present invention is not limited to the above-mentioned technical field. One aspect of the technical field relates to a product, method, or method of manufacture. Or, the present invention. One aspect of this is a process, machine, manufacture, or composition. This relates to matter. Therefore, the invention disclosed more specifically in this specification One aspect of the technical field is semiconductor devices, display devices, liquid crystal display devices, light-emitting devices, and lighting devices. A device, an energy storage device, a memory device, an imaging device, a method for driving them, or a method for manufacturing them. This can be given as an example. [Background technology]

[0002] Electroluminescence (EL) using organic compounds The practical application of light-emitting devices (organic EL devices) that utilize these (ence) is progressing. The basic configuration of a light-emitting device is an organic compound layer (EL layer) containing light-emitting material between a pair of electrodes. It is sandwiched in between. A voltage is applied to this device to inject a carrier, and the carrier By utilizing the recombination energy, light emission can be obtained from light-emitting materials.

[0003] Since such light-emitting devices are self-emissive, when used as pixels in a display, they become liquid crystals. Compared to other displays, it has advantages such as higher visibility and the elimination of the need for a backlight, and flat panel displays. It is particularly suitable for displays. Furthermore, displays using such light-emitting devices are Another major advantage is that it can be manufactured to be thin and lightweight. Furthermore, it is characterized by its extremely fast response speed. It is one of them.

[0004] Furthermore, these light-emitting devices allow for the continuous formation of a light-emitting layer in two dimensions. This allows for the emission of light in a planar manner. This is a point light source, such as an incandescent light bulb or an LED. Alternatively, it is a characteristic that is difficult to obtain with linear light sources such as fluorescent lamps, and therefore can be applied to lighting and other applications. It also has high value as a source of nutrients.

[0005] Thus, displays or lighting devices using light-emitting devices are suitable for a variety of electronic devices. While suitable, research and development are underway to find light-emitting devices with even better characteristics.

[0006] One of the issues often raised when discussing OLED devices is light extraction. It suffers from low efficiency. To improve this, a layer made of a low refractive index material is formed inside the EL layer. A configuration that achieves this has been proposed (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] U.S. Patent Application Publication No. 2020 / 0176692 [Non-patent literature]

[0008] [Non-Patent Document 1] 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. [Overview of the project] [Problems that the invention aims to solve]

[0009] One aspect of the present invention aims to provide a light-emitting device with high luminescence efficiency. In one aspect of the present invention, a light-emitting device, light-emitting apparatus, electronic device, and display device with low power consumption are provided. The aim is to provide either an electronic device or an electronic device.

[0010] The present invention only needs to solve one of the above-mentioned problems. [Means for solving the problem]

[0011] One aspect of the present invention is a first electrode, a second electrode, the first electrode, the second electrode and , has an EL layer located between, and the EL layer comprises at least an emissive layer and a first layer, It has a second layer and a third layer, and the first layer comprises the first electrode and the light-emitting layer, The third layer is located between the first layer and the light-emitting layer, and the second layer is located between the first layer and the light-emitting layer. The layer is located between the first layer and the third layer, and the first layer is the first organic The second layer contains a compound, the second layer contains a second organic compound, and the third layer contains a third organic The compound comprises any wavelength of the second organic compound between 450 nm and 650 nm. The ordinary refractive index of the first organic compound in light is the ordinary refractive index of the first organic compound in light of the wavelength and and a light-emitting device having a refractive index higher than that of the third organic compound at the aforementioned wavelength of light. ru.

[0012] Alternatively, another aspect of the present invention is a first electrode, a second electrode, the first electrode, and the It has a second electrode and an EL layer located between them, and the EL layer comprises at least an emissive layer. It has a first layer, a second layer, and a third layer, and the first layer comprises the first electrode and the The third layer is located between the first layer and the light-emitting layer. The second layer is located between the first layer and the third layer, and the first layer is The first layer contains an organic compound, the second layer contains a second organic compound, and the third layer contains , comprising a third organic compound, the second organic compound having a wavelength of 455 nm to 465 nm The ordinary refractive index of the first organic compound at any of the wavelengths of light is The emission of light from the third organic compound at a wavelength higher than the ordinary refractive index of the third organic compound at the ordinary refractive index of the wavelength of light. It is a device.

[0013] Alternatively, another aspect of the present invention is a first electrode, a second electrode, the first electrode, and the It has a second electrode and an EL layer located between them, and the EL layer comprises at least an emissive layer. It has a first layer, a second layer, and a third layer, and the first layer comprises the first electrode and the The third layer is located between the first layer and the light-emitting layer. The second layer is located between the first layer and the third layer, and the first layer is The first layer contains an organic compound, the second layer contains a second organic compound, and the third layer contains , comprising a third organic compound, the ordinary refractive index of the second organic compound at a wavelength of 633 nm The first organic compound's ordinary refractive index at a wavelength of 633 nm and the third organic compound This is a light-emitting device with a refractive index higher than that of an object at a wavelength of 633 nm.

[0014] Alternatively, another aspect of the present invention is a first electrode, a second electrode, the first electrode, and the It has a second electrode and an EL layer located between them, and the EL layer comprises at least an emissive layer. It has a first layer, a second layer, and a third layer, and the first layer comprises the first electrode and the The third layer is located between the first layer and the light-emitting layer. The second layer is located between the first layer and the third layer, and the light-emitting layer is The first layer comprises a light-emitting material that exhibits emission with a peak wavelength of wavelength λnm, and the first layer is a first organic The compound comprises, the second layer comprises a second organic compound, and the third layer comprises a third organic compound The compound comprises the second organic compound, and the ordinary refractive index of the second organic compound at the wavelength λnm is the same as the first organic compound. The ordinary refractive index of the organic compound at the wavelength λnm and the wavelength λ of the third organic compound This is a light-emitting device with a refractive index higher than that of ordinary light at nm.

[0015] Alternatively, in another aspect of the present invention, in the above configuration, the HOMO of the first organic compound In a light-emitting device in which the difference between the position and the HOMO level of the third organic compound is 0.2 eV or less, be.

[0016] Alternatively, in another aspect of the present invention, the above configuration comprises the first organic compound and the third This is a light-emitting device made of the same organic compound.

[0017] Alternatively, in another aspect of the present invention, in the above configuration, the third layer described above does not contain fluorine. It is a light-emitting device.

[0018] Alternatively, in another aspect of the present invention, in the above configuration, the film of the first to third layers The light-emitting devices have a thickness of 25 nm to 70 nm.

[0019] Alternatively, in another aspect of the present invention, in the above configuration, the film thickness of the first layer and the third This is a light-emitting device in which the thickness of the second layer is greater than the thickness of the first layer.

[0020] Alternatively, in another aspect of the present invention, in the above configuration, the aforementioned second organic at a wavelength λnm The difference between the paraphotometric refractive index of the compound and the paraphotometric refractive index of the first organic compound, and the second organic compound The difference between the paraphotometric refractive index of the compound and the paraphotometric refractive index of the third organic compound is 0.2 or more and less than 0.5, respectively. It is a light-emitting device.

[0021] Alternatively, in another aspect of the present invention, the above configuration comprises the first organic compound and the third The difference in the ordinary refractive index of the organic compound at the wavelength λnm is 0.1 or less. It is S.

[0022] Alternatively, in another aspect of the present invention, in the above configuration, the thickness of the second layer and the second The product of the ordinary refractive indices of the organic compound at the wavelength λnm is 70, which is 1 / 4 of the wavelength λnm. This is a light-emitting device with a brightness of % or more and 130% or less.

[0023] Alternatively, in another aspect of the present invention, in the above configuration, λ is the emission of light by the light-emitting material. It is a light-emitting device that emits light at the peak wavelength.

[0024] Alternatively, in another aspect of the present invention, in the above configuration, the λ is 450 or more and 650 or less It is a light-emitting device that has one of the following values.

[0025] Alternatively, in another aspect of the present invention, in the above configuration, the λ is 455 or more and 465 or less It is a light-emitting device that has one of the following values.

[0026] Alternatively, another aspect of the present invention is a light-emitting device in the above configuration in which λ is 633. That is the case.

[0027] Alternatively, in another aspect of the present invention, in the above configuration, the first electrode includes a reflecting electrode. It is an optical device.

[0028] Alternatively, in another aspect of the present invention, in the above configuration, the GSP (mV / nm) of the third layer The value obtained by subtracting the GSP (mV / nm) of the second layer from ) is 10 (mV / nm) or less. It is a light-emitting device.

[0029] Alternatively, in another aspect of the present invention, in the above configuration, the GSP (mV / nm) of the second layer The value obtained by subtracting the GSP (mV / nm) of the first layer from ) is 10 (mV / nm) or less. It is a light-emitting device.

[0030] Alternatively, in another aspect of the present invention, in the above configuration, the GSP (mV / nm) of the third layer This is a light-emitting device in which the GSP (mV / nm) of the second layer is larger than that of the second layer.

[0031] Alternatively, in another aspect of the present invention, in the above configuration, the GSP (mV / nm) of the third layer This is a light-emitting device in which the GSP (mV / nm) of the first layer is greater than that of the first layer.

[0032] Alternatively, in another aspect of the present invention, in the above configuration, the GSP (mV / nm) of the second layer This is a light-emitting device in which the GSP (mV / nm) of the first layer is greater than that of the first layer.

[0033] Alternatively, in another aspect of the present invention, in the above configuration, the first organic compound and the third This is a light-emitting device in which different organic compounds are used.

[0034] Alternatively, another aspect of the present invention comprises a first light-emitting device and a second light-emitting device. The first light-emitting device has the configuration described in any of the above, and the second light-emitting device The device has an EL layer between the third electrode and the second electrode, and the second light-emitting device The EL layer comprises at least an emissive layer, a fourth layer, a fifth layer, and a sixth layer, and The fourth layer, the fifth layer, and the sixth layer are the first layer, the second layer, and the third layer. Having the same configuration, the peak emission of the light-emitting material contained in the light-emitting layer of the first light-emitting device The wavelength and the peak wavelength of emission of the light-emitting material contained in the light-emitting layer of the second light-emitting device are 30 These are containers that differ by more than nm.

[0035] Alternatively, another aspect of the present invention is a light-emitting device as described above, a sensor, and an operation It is a display device having buttons and a speaker or microphone.

[0036] Alternatively, another aspect of the present invention comprises the above-mentioned display device, a sensor, an operation button, and a speaker. Or it is an electronic device having a microphone.

[0037] Alternatively, another aspect of the present invention is a light-emitting device as described above, and a transistor, Alternatively, it is a light-emitting device having a substrate.

[0038] Alternatively, another aspect of the present invention comprises the light-emitting device described in any of the above descriptions and a housing. It is a lighting device.

[0039] In this specification, the term "light-emitting device" includes image display devices that use light-emitting devices. Also, connectors, such as anisotropic conductive film or TCP (Tape) may be attached to the light-emitting device. Module with Carrier Package attached, print to TCP A module equipped with a wiring board, or a light-emitting device, with COG (Chip On Glas Modules with ICs (integrated circuits) directly mounted using the s) method may also be included as light-emitting devices. Furthermore, lighting fixtures and the like may have light-emitting devices. [Effects of the Invention]

[0040] In one aspect of the present invention, a light-emitting device with high luminous efficiency can be provided. Alternatively, this In one aspect of the invention, a light-emitting device, light-emitting apparatus, electronic device, display device, and We can provide either an electronic device or an electronic device.

[0041] Furthermore, the description of these effects does not preclude the existence of other effects. The embodiment does not necessarily have to have all of these effects. Furthermore, other effects are... This will become clear from the description in the specification, drawings, claims, etc., and the specification, drawings Furthermore, it is possible to extract other effects from the descriptions in the claims and other documents. [Brief explanation of the drawing]

[0042] [Figure 1] Figures 1(A), 1(B), 1(C), and 1(D) are schematic diagrams of light-emitting devices. [Figure 2] Figures 2(A) and 2(B) are diagrams representing an active matrix type light-emitting device. [Figure 3] Figures 3(A) and 3(B) are diagrams representing an active matrix type light-emitting device. [Figure 4] Figure 4 is a diagram representing an active matrix type light-emitting device. [Figure 5] Figures 5(A) and 5(B) are diagrams representing passive matrix type light-emitting devices. [Figure 6] Figures 6(A) and 6(B) are diagrams representing lighting devices. [Figure 7] Figures 7(A), 7(B1), 7(B2), and 7(C) are diagrams representing electronic devices. [Figure 8] Figures 8(A), 8(B), and 8(C) are diagrams representing electronic devices. [Figure 9] Figure 9 is a diagram representing a lighting device. [Figure 10] Figure 10 is a diagram representing a lighting device. [Figure 11] Figure 11 is a diagram representing an in-vehicle display device and lighting system. [Figure 12] Figures 12(A) and 12(B) are diagrams representing electronic devices. [Figure 13] Figures 13(A), 13(B), and 13(C) are diagrams representing electronic devices. [Figure 14] Figures 14(A) to 14(D) show examples of the configuration of a display device. [Figure 15] Figures 15(A) to 15(F) show examples of methods for manufacturing a display device. [Figure 16] Figures 16(A) to 16(F) show examples of methods for manufacturing a display device. [Figure 17] Figure 17 shows the refractive indices of PCBDBtBB-02 and mmtBumTPoFBi-02. [Figure 18] Figure 18 shows the luminance-current density characteristics of light-emitting device 1, reference light-emitting device 1, and reference light-emitting device 2. [Figure 19] Figure 19 shows the luminance-voltage characteristics of light-emitting device 1, reference light-emitting device 1, and reference light-emitting device 2. [Figure 20] Figure 20 shows the current efficiency-luminance characteristics of light-emitting device 1, reference light-emitting device 1, and reference light-emitting device 2. [Figure 21] Figure 21 shows the current density-voltage characteristics of light-emitting device 1, reference light-emitting device 1, and reference light-emitting device 2. [Figure 22]Figure 22 shows the blue index-luminance characteristics of light-emitting device 1, reference light-emitting device 1, and reference light-emitting device 2. [Figure 23] Figure 23 shows the emission spectra of light-emitting device 1, reference light-emitting device 1, and reference light-emitting device 2. [Figure 24] Figure 24 shows the refractive indices of BBA(βN2)B-03 and mmtBuBioFBi. [Figure 25] Figure 25 shows the luminance-current density characteristics of the light-emitting device 10 and the comparison light-emitting device 10. [Figure 26] Figure 26 shows the luminance-voltage characteristics of the light-emitting device 10 and the comparison light-emitting device 10. [Figure 27] Figure 27 shows the current efficiency-luminance characteristics of the light-emitting device 10 and the comparative light-emitting device 10. [Figure 28] Figure 28 shows the current density-voltage characteristics of the light-emitting device 10 and the comparison light-emitting device 10. [Figure 29] Figure 29 shows the blue index-current density characteristics of the light-emitting device 10 and the comparison light-emitting device 10. [Figure 30] Figure 30 shows the emission spectra of the light-emitting device 10 and the reference light-emitting device 10. [Figure 31] Figure 31 shows the viewing angle characteristics of the light-emitting device 10 and the comparison light-emitting device 10. [Figure 32] Figure 32 shows the relative luminance-time variation characteristics of the light-emitting device 10 and the comparison light-emitting device 10. [Figure 33] Figure 33 shows the luminance-current density characteristics of the light-emitting device 20. [Figure 34] Figure 34 shows the luminance-voltage characteristics of the light-emitting device 20. [Figure 35] Figure 35 shows the current efficiency-luminance characteristics of the light-emitting device 20. [Figure 36] Figure 36 shows the current density-voltage characteristics of the light-emitting device 20. [Figure 37]Figure 37 shows the blue index-luminance characteristics of the light-emitting device 20. [Figure 38] Figure 38 shows the emission spectrum of the light-emitting device 20. [Figure 39] Figure 39 shows the normalized luminance-time variation characteristics of the light-emitting device 20. [Figure 40] Figure 40 shows the luminance-current density characteristics of the light-emitting device 30. [Figure 41] Figure 41 shows the brightness-voltage characteristics of the light-emitting device 30. [Figure 42] Figure 42 shows the current efficiency-luminance characteristics of the light-emitting device 30. [Figure 43] Figure 43 shows the current density-voltage characteristics of the light-emitting device 30. [Figure 44] Figure 44 shows the blue index-current density characteristics of the light-emitting device 30. [Figure 45] Figure 45 shows the emission spectrum of the light-emitting device 30. [Figure 46] Figure 46 shows the relative luminance-time variation characteristics of the light-emitting device 30. [Figure 47] Figures 47(A) and 47(B) show the refractive indices of BBA(βN2)B-03, mmtBuBioFBi, and mmtBumTPoFBi-04. [Figure 48] Figure 48 shows the luminance-current density characteristics of light-emitting device 40, light-emitting device 41, and comparison light-emitting device 40. [Figure 49] Figure 49 shows the current efficiency-luminance characteristics of light-emitting device 40, light-emitting device 41, and comparison light-emitting device 40. [Figure 50] Figure 50 shows the luminance-voltage characteristics of light-emitting device 40, light-emitting device 41, and comparison light-emitting device 40. [Figure 51] Figure 51 shows the current density-voltage characteristics of light-emitting device 40, light-emitting device 41, and comparison light-emitting device 40. [Figure 52]Figure 52 shows the blue index-luminance characteristics of light-emitting device 40, light-emitting device 41, and comparison light-emitting device 40. [Figure 53] Figure 53 shows the power efficiency-luminance characteristics of light-emitting device 40, light-emitting device 41, and comparative light-emitting device 40. [Figure 54] Figure 54 shows the emission spectra of light-emitting device 40, light-emitting device 41, and comparison light-emitting device 40. [Figure 55] Figure 55 shows the normalized luminance-time variation characteristics of light-emitting device 40, light-emitting device 41, and comparative light-emitting device 40. [Figure 56] Figure 56 shows the comparison light-emitting device 50 and the brightness-current density characteristics of the light-emitting device 50. [Figure 57] Figure 57 shows the comparison light-emitting device 50 and the brightness-voltage characteristics of the light-emitting device 50. [Figure 58] Figure 58 shows the current efficiency-luminance characteristics of the comparative light-emitting device 50 and the light-emitting device 50. [Figure 59] Figure 59 shows the current density-voltage characteristics of the comparison light-emitting device 50 and the light-emitting device 50. [Figure 60] Figure 60 shows the power efficiency-luminance characteristics of the comparative light-emitting device 50 and the light-emitting device 50. [Figure 61] Figure 61 shows the comparison light-emitting device 50 and the emission spectrum of the light-emitting device 50. [Figure 62] Figures 62(A) and 62(B) show the refractive indices of mmtBumTPoFBi-04, PCBBiPDBt-02, and mmtBuBiFF. [Figure 63] Figure 63 shows the refractive indices of mmtBumBPTzn, Li-6mq, and BisBTc. [Figure 64] Figure 64 shows the refractive indices of mmtBumTPoFBi-04, DBfBB1TP, and mmtBuBioFBi. [Figure 65]Figure 65 shows the emission spectrum of DPhA-tBu4DABNA in a toluene solution. [Figure 66] Figure 66 shows the luminance-current density characteristics of the light-emitting device 60. [Figure 67] Figure 67 shows the current efficiency-luminance characteristics of the light-emitting device 60. [Figure 68] Figure 68 shows the luminance-voltage characteristics of the light-emitting device 60. [Figure 69] Figure 69 shows the current density-voltage characteristics of the light-emitting device 60. [Figure 70] Figure 70 shows the blue index-luminance characteristics of the light-emitting device 60. [Figure 71] Figure 71 shows the emission spectrum of the light-emitting device 60. [Modes for carrying out the invention]

[0043] The embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is as follows Not limited to the description, the form and details thereof may be described without departing from the spirit and scope of the present invention. Those skilled in the art will readily understand that the invention can be modified in various ways. Therefore, the present invention is as follows: This should not be interpreted as being limited to the contents described in the embodiments.

[0044] Furthermore, when light is incident on a material with optical anisotropy, light from a vibration plane parallel to the optical axis is called extraordinary light. (Line), light from a perpendicular plane of vibration is called ordinary light (line), but the refractive index of the material in relation to ordinary light and abnormality The refractive index for light may differ. In such cases, anisotropy analysis can be performed. The refractive index of ordinary light and the refractive index of extraordinary light can be separated and their respective refractive indices can be calculated. In the details, if the measured material has both an ordinary refractive index and an extraordinary refractive index, The refractive index shall be used as the indicator.

[0045] (Embodiment 1) Figure 1(A) shows a diagram representing a light-emitting device according to one embodiment of the present invention. The vice has a first electrode 101, a second electrode 102, and an EL layer 103, and the EL layer 1 03 is at least hole transport layer 112 (first hole transport layer 112-1, second hole transport layer It has 112-2 and a third hole transport layer 112-3), and a light-emitting layer 113. The light layer 113 is a layer having at least a light-emitting material, and the hole transport layer 112 is a layer with the light-emitting layer 113. It is located between the first electrodes 101. The EL layer 103 is a hole injection layer 1 as shown in the figure. 11. It may also have an electron transport layer 114 and an electron injection layer 115, and also a carrier In a configuration in which an ablock layer or exciton blocking layer, an intermediate layer, or other functional layer is formed That's fine.

[0046] In one aspect of the present invention, the first hole transport layer 112-1 to the third hole transport layer 112-3 are Each contains the first to third organic compounds, and the first to third organic compounds The organic compound is in the first hole transport layer 112-1 to the third hole transport layer 112-3. Each of these must be present in a quantity of 80% or more.

[0047] Furthermore, in a light-emitting device according to one aspect of the present invention, the second organic compound is the first organic compound and It has a higher paraphotonic refractive index than the third organic compound. That is, the second hole transport layer 11 2-2 is more orthophotometric than the first hole transport layer 112-1 and the third hole transport layer 112-3. This is a segment with a high conversion rate.

[0048] By having such a configuration, the light-emitting device of one aspect of the present invention emits light from the light-emitting material Since the light is reflected at the interface of each hole transport layer, only the reflective electrode is used to reflect it. This allows for the reflection of more light, improving the external quantum efficiency. Sometimes, the effect of surface plasmons at the reflective electrode can be reduced, thus energy This reduces light loss and allows for more efficient light extraction.

[0049] In one aspect of the present invention, the paraphotorefractive index of the second organic compound for light of a certain wavelength λnm The difference between the parametric refractive index of the first organic compound and the parametric refractive index of the second organic compound and the third organic compound. The difference in the refractive index of each compound is 0.1 or more and less than 0.5, preferably 0.2 or more and 0.5. The refractive index of these is less than, more preferably 0.3 or more and less than 0.5. The difference being within the above range means that other light-emitting materials, including light-emitting materials that emit light of different wavelengths, No problems arise when a hole transport layer 112 having the same configuration as this light-emitting device is applied to the vise. This process is less prone to failure and eliminates the need to create separate hole transport layers 112 for each emission color, making it cost-effective. This is the result.

[0050] Furthermore, the ordinary refractive index of the second hole transport layer 112-2 and the first hole transport layer for light of wavelength λnm are as follows: The difference in the paraphotometric refractive index of the transport layer 112-1, and the difference in the paraphotometric refractive index of the second hole transport layer 112-2 The difference in the ordinary refractive index of the hole transport layers 112-3 is between 0.2 and 0.5. More preferable. The wavelength λnm is any of the ranges between 450nm and 650nm or the entire range. When a light-emitting device emits light in the blue region, the wavelength λnm is between 455nm and 465nm. It is any or all of the m range. Also, the wavelength λnm is the emission peak wavelength of the light-emitting material. This is preferable. Note that the wavelength λnm, which is commonly used as an indicator of refractive index, is 633nm. These values ​​can be used as indicators for the wavelength λnm.

[0051] The paraphotometric refractive indices of the first and third organic compounds at a wavelength of λnm are 1. 40 to 1.75, more specifically in the blue emission region (455nm to 465nm) The normal refractive index is 1.40 or more and 1.75 or less, or 63, which is normally used for measuring refractive index. The ordinary refractive index at 3 nm is preferably 1.40 or higher and 1.70 or lower. The ordinary refractive indices of the first hole transport layer 112-1 and the third hole transport layer 112-3 are as described above. It is more preferable that the wavelengths of the first organic compound and the third organic compound are within the specified range. The difference in the refractive index at λnm is preferably 0.1 or less.

[0052] The second organic compound has a paraphotonic refractive index of 1.75 or greater at a wavelength of λnm, specifically, blue. The refractive index in the luminescent region (455 nm to 465 nm) is 1.75 to 2.4. The ordinary refractive index at 633 nm light, which is typically used for measuring refractive index, is 1.7 It is preferable that the value is between 5 and 2.30. It is more preferable that the folding rate is within the above range.

[0053] Furthermore, the difference in HOMO levels between the first organic compound and the third organic compound is less than 0.2 eV. Preferably, the voltage should be 0.1 eV or less, as this improves hole transportability. The difference in HOMO levels between the second organic compound and the first and third organic compounds is By setting each to 0.2 eV or less, preferably 0.1 eV or less, hole transportability is improved. Therefore, it is preferable.

[0054] Here, in a light-emitting device according to one aspect of the present invention, the first hole transport layer 112-1 to the third The thickness of the hole transport layer 112-3 is preferably 25 nm or more and 70 nm or less. Furthermore, in a light-emitting device according to one aspect of the present invention, the first hole transport layer 112-1 and The third hole transport layer 112-3 is located on the side that is not in contact with the second hole transport layer 112-2, and each of these is located on the side that is not in contact with the second hole transport layer 112-2. By installing a buffer layer such as an electron injection layer or an electron blocking layer, the characteristics of the light-emitting device are improved. Therefore, the film thickness of the second hole transport layer 112-2 is greater than the film thickness of the first hole transport layer 112-1. It is preferable that the thickness is greater than that of the second hole transport layer 112-3. The product of the ordinary refractive index of the transmission layer 112-2 at wavelength λnm and the film thickness is 70% or more of λ / 4. It is preferable to have a value of 130% or less because it strengthens the light interference. Therefore, the light reflected at the interface between the third hole transport layer 112-3 and the second hole transport layer 112-2 And the light reflected at the interface between the second hole transport layer 112-2 and the first hole transport layer 112-1 Since the signal can be amplified by interference, it provides a more efficient light-emitting device. You will be able to do that.

[0055] Furthermore, there is a high probability that the first organic compound and the third organic compound are the same organic compound. This is preferable because it ensures transportability and reduces the amount of material used in fabricating light-emitting devices. Furthermore, the third hole transport layer 112-3 contains fluorine to ensure reliability. It is preferable that this is not done. Also, common hall transport of a display device having the three primary colors red, green, and blue. For use as a layer, it is undesirable for the optical interference that enhances specific light to become too strong. Therefore, the first and third organic compounds contain fluorine, which has a low atomic refraction. It is preferable that there be none.

[0056] The first hole transport layer 112-1 and the third hole transport layer 112-3 are made of materials with a relatively small refractive index. While it is formed using quality, there is usually a trade-off between high carrier transportability and low refractive index. It is located there. This is because carrier transport in organic compounds originates from the presence of unsaturated bonds. Organic compounds with large pores and many unsaturated bonds tend to have a high refractive index. Even if the material has a low refractive index, if the carrier transport is poor, the drive voltage will increase, and carrier bus Problems such as reduced luminous efficiency or reliability due to lance collapse occur, resulting in poor performance. It becomes impossible to obtain a light-emitting device with the necessary properties. Also, sufficient carrier transport Even materials that possess properties and have a low refractive index may have an unstable structure, resulting in a glass transition temperature (T g) If there are durability issues, it becomes impossible to obtain a reliable light-emitting device. It ends up happening.

[0057] Therefore, it can be used in the first hole transport layer 112-1 and the third hole transport layer 112-3. As an example of an organic compound, it has a first aromatic group, a second aromatic group, and a third aromatic group, The first, second, and third aromatic groups are bonded to the same nitrogen atom. It is preferable to use a monoamine compound that is present in the following form.

[0058] The monoamine compound in question forms bonds using sp3 hybrid orbitals relative to the total number of carbon atoms in the molecule. The carbon content is preferably between 23% and 55%, and also, 1 H-NMR In the measurement of noamine compounds, the integral value of signals less than 4 ppm was 4p It is preferable that the compound exceeds the integrated value of signals above pm.

[0059] Furthermore, the monoamine compound has at least one fluorene skeleton and the first aroma One or more of the group group, the second aromatic group, and the third aromatic group are fluorescein. It is preferable that it has a fluoren skeleton. Furthermore, fluorenylamine has the effect of raising the HOMO level. Because of this effect, when three fluorenes are attached to the nitrogen of the monoamine compound, HOMO The energy level may rise significantly. In this case, the HOMO level of the surrounding material (for example, the second level) The difference with the HOMO level of organic compounds becomes large, affecting the drive voltage and reliability, etc. Therefore, the first aromatic group, the second aromatic group and the third It is even more preferable that one or two of the aromatic groups are fluorene skeletons.

[0060] Examples of organic compounds exhibiting hole transport properties as described above include those with the following general formula (G h1 1)~( G h1 Examples of organic compounds having a structure like that in 4) are given.

[0061] [ka]

[0062] The above general formula (G h1 1) In Ar 1 Ar 2 Each of them independently represents a benzene ring or This represents a substituent in which two or three benzene rings are bonded to each other. However, Ar 1 Ar 2 of One or both are carbon atoms with 1 to 12 carbon atoms, where the carbon atoms form bonds only in sp3 hybrid orbitals. Having one or more hydrogenated groups, Ar1 and Ar 2 to all of the hydrocarbon groups bonded to the total carbon contained is 8 or more, and Ar 1 and Ar 2 bonded to either one of the total carbon contained in all of the hydrocarbon groups thus bonded is 6 or more. Note that Ar 1 or Ar 2 when a plurality of linear alkyl groups having 1 or 2 carbon atoms are bonded thereto as the hydrocarbon group, the linear alkyl groups may be bonded to each other to form a ring.

[0063]

Chemical formula

[0064] In the above general formula (G h1 2), m and r each independently represent 1 or 2, and m + r is 2 or 3. Also, t represents an integer from 0 to 4, and is preferably 0. Also, R 5 represents either hydrogen or a hydrocarbon group having 1 to 3 carbon atoms. Note that when m is 2 the type, number of substituents, and position of the bonding hands of the two phenylene groups may be the same or different, and when r is 2, the type, number of substituents, and position of the bonding hands of the two phenyl groups may be the same or different. Also, when t is an integer from 2 to 4, the plurality of R 5 may each be the same or different, and R 5 is such that adjacent groups may be bonded to each other to form a ring.

[0065]

Chemical formula

[0066] The above general formula (G h1 2) and (G h1 3) In this case, n and p are each independently 1 or It represents 2, and n+p is either 2 or 3. s represents an integer from 0 to 4, and is preferably 0. It's nice. Also, R 4 n represents either hydrogen or a hydrocarbon group having 1 to 3 carbon atoms, and n If the value is 2, the types of substituents, the number of substituents, and the bond positions of the two phenylene groups. The positions may be the same or different, and when p is 2, the positions of the two phenyl groups The type of substitution group, the number of substituents, and the position of the bond may be the same or different. If s is an integer between 2 and 4, then multiple R 4 They can be the same or different. .

[0067] [ka]

[0068] The above general formula (G h1 2)~(G h1 In 4), R 10 ~R 14 and R 20 ~ R 24 Each of these independently represents the number of carbon atoms that form bonds using only sp3 hybrid orbitals, either hydrogen or carbon. Represents 1 to 12 hydrocarbon groups. Note that R 10 ~R 14 At least three of the following, and R 2 0 ~R 24 Preferably, at least three of them are hydrogen. Carbon is only in sp3 hybrid orbitals. The hydrocarbon groups with 1 to 12 carbon atoms that form the bond include the tert-butyl group and Cyclohexyl groups are preferred. However, R 10 ~R 14 and R20 ~R 24 Included The total number of carbon atoms is 8 or more, and R 10 ~R 14 or R 20 ~R 24 throat The total number of carbon atoms contained in one of the elements is 6 or more. 4 , R 10 ~R 14 Oh biR 20 ~R 24 In this case, adjacent groups may be bonded to each other to form a ring.

[0069] Also, the above general formula (G h1 1)~(G h1 4) In this case, u is an integer from 0 to 4, each independently. It represents a number, preferably 0. If u is an integer between 2 and 4, multiple R 3 Each is the same They can be the same or different. Also, R 1 , R 2 and R 3 Each of them independently has 1 carbon atom. Represents alkyl groups up to 4, R 1 and R 2 They may be joined to each other to form a ring.

[0070] Furthermore, it can be used in the first hole transport layer 112-1 and the third hole transport layer 112-3. One material having capable hole transport is one having at least one aromatic group, and the aromatic group The fragrance group has a first to third benzene ring and at least three alkyl groups. Arylamine compounds that are also preferred. The benzene rings are bonded in this order, with the first benzene ring directly bonded to the nitrogen of the amine. Let's assume that.

[0071] Furthermore, the first benzene ring may have a substituted or unsubstituted phenyl group. It is preferable to have a substituted phenyl group. Also, the second benzene ring or the The third benzene ring may have a phenyl group substituted with an alkyl group.

[0072] Furthermore, of the first to third benzene rings, two or more benzene rings, Preferably, hydrogen is not directly bonded to the carbon atoms at positions 1 and 3 of all benzene rings. The first to third benzene rings mentioned above, and the alkyl group substituted with the phenyl group mentioned above. The group is bonded to at least three of the alkyl groups mentioned above, and to the nitrogen of the amine mentioned above. It is assumed that this is the case.

[0073] Furthermore, it is preferable that the above arylamine compound further has a second aromatic group. The aromatic group of 2 is an unsubstituted monocycle, or a fused ring of three or fewer rings, substituted or unsubstituted. It is preferable that the group is a substituted or unsubstituted fused ring of three or fewer rings. The fused ring is a group having a fused ring with 6 to 13 carbon atoms forming the ring. Preferably, the group has a fluorene ring. A dimethylfluorenyl group is preferred as the component.

[0074] Furthermore, it is preferable that the above arylamine compound further has a third aromatic group. Aromatic groups 3 are groups that have one to three substituted or unsubstituted benzene rings.

[0075] The above-mentioned at least three alkyl groups, and alkyl groups substituted on the phenyl group, have 2 or more carbon atoms. It is preferable that the alkyl group is a chain-type alkyl group having 5 carbon atoms. In particular, the alkyl group has a number of carbon atoms A chain alkyl group having 3 to 5 carbon atoms in the branch is preferred, and a t-butyl group is more preferred. Yes.

[0076] Examples of the material having the hole transporting property as described above include organic compounds having structures such as the following general formula (G h2 1) to (G h2 3).

[0077]

Chemical formula

[0078] In the above general formula (G h2 1), Ar 101 represents a substituted or unsubstituted benzene ring, or a substituent in which two or three substituted or unsubstituted benzene rings are bonded to each other. .

[0079]

Chemical formula

[0080] In the above general formula (G h2 2), x and y each independently represent 1 or 2, and x +y is 2 or 3. Also, R 109 represents an alkyl group having 1 to 4 carbon atoms, and w represents an integer of 0 to 4. Also, R 141 to R 145 each independently represent any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a cycloalkyl group having 5 to 12 carbon atoms. When w is an integer of 2 or more, the plurality of R may be the same or different from each other. 109 When x is 2, the types, numbers of substituents, and positions of bonds of the two phenylene groups may be the same or different. Also, when y is 2, the two R ​ 141 ~R 145 The types and number of substituents on the phenyl group having the same It may be different, or it may be different.

[0081] [ka]

[0082] Note that the above general formula (G h2 3) In R 101 ~R 105 Each of them independently produces hydrogen and carbon Alkyl alkyl groups with 1 to 6 carbon atoms, cycloalkyl groups with 6 to 12 carbon atoms, and Represents either a substituted or unsubstituted phenyl group.

[0083] Also, the above general formula (G h2 1)~(G h2 3) In R 106 , R 107 and R 108 Each of the characters independently represents an alkyl group having 1 to 4 carbon atoms, and v represents an integer from 0 to 4. Oh, if v is 2 or more, multiple R 108 These can be the same or different. Also, R 111 ~R 115 One of them is a substituent represented by the above general formula (g1), and the rest Each of these independently comprises hydrogen, an alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted atom. It represents any one of the henyl groups. Also, in the above general formula (g1), R 121 ~R 12 5 One of them is a substituent represented by the general formula (g2) above, and the remaining ones are independently hydrogen and carbon Alkyl groups having 1 to 6 carbon atoms, and alkyl groups substituted with 1 to 6 carbon atoms represents any one of phenyl groups. In the above general formula (g2), R 131 to R 1 35 each independently represents any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a phenyl group substituted with an alkyl group having 1 to 6 carbon atoms. Among R to R 111 to R 1 15 R 121 to R 125 and R 131 to R 135 at least three or more of them are alkyl groups having 1 to 6 carbon atoms, and the substituted or unsubstituted phenyl groups in R 111 to R 115 are 1 or less, and the phenyl groups substituted with alkyl groups having 1 to 6 carbon atoms in R to R 121 to R 125 and R 131 to R 135 are 1 or less. Also, among the three combinations of R R and R 112 and R 114 R 122 and R 124 and among the three combinations of R 132 and R 134 in at least two of the three combinations, at least one R is other than hydrogen.

[0084] The organic compound having hole transporting properties as described above has a normal light refractive index in the blue light emission region (455 nm or more and 465 nm or less) of 1.40 or more and 1.75 or less, or a normal light refractive index in the 633 nm light usually used for measuring the refractive index of 1.40 or more and 1.70 or less, and is an organic compound with good hole transporting properties. Also, at the same time, it has a high Tg and good reliability of the organic compound. ​It is also possible to obtain a compound. Such an organic compound also has sufficient hole transportability and is thus preferably used as the material for the first hole transport layer 112-1 and the third hole transport layer 112-3.

[0085] In addition, 1,1-bis[4-[N,N-di(p-tolyl)amino]phenyl]cyclo hexane (abbreviation: TAPC), etc. can also be used.

[0086] Further, the second hole transport layer 112-2 is formed using an organic compound having a relatively large refractive index. As such an organic compound, compounds having a condensed aromatic hydrocarbon ring or a condensed heteroaromatic ring are preferred. As the condensed aromatic hydrocarbon ring, those containing a naphthalene structure, such as a naphthalene ring, an anthracene ring, a phenanthrene ring, or a triphenylene ring, are preferred. As the condensed heteroaromatic ring, those containing the structure of a carbazole ring, a dibenzofuran ring, or a dibenzothiophene ring are preferred. ring are preferred. Further, for example, benzo[b]naphtho[1,2-d]fura n is preferred because it contains the structure of a dibenzofuran ring.

[0087] In addition, organic compounds containing one or more elements after the third period, organic compounds having a terphenyl skeleton, or organic compounds containing both can be preferably used. For example, a biphenyl group substituted with a naphthyl group or a phenyl group substituted with a dibenzofuranyl group can be said to contain a terphenyl skeleton. Specifically, N,N-bis[4-(6-phenylbenzo[b] naphtho[1,2-d]furan-8-yl)phenyl]-4-amino-p-terphenyl( abbreviation: BnfBB1TP), 4,4'-bis[4-(2-naphthyl)phenyl]-4'' ​​​- Phenyltriphenylamine (abbreviation: βNBiB1BP), N,N-bis[4-(dibe [4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB) 1TP), 4-[4'-(carbazol-9-yl)biphenyl-4-yl]-4'-( 2-Naphthyl)-4''-Phenyltriphenylamine (abbreviation: YGTBiβNB), 5 ,5'-diphenyl-2,2'-di-5H-[1]benzothieno[3,2-c]carbazo Materials such as BB (abbreviated as BisBTc) can be suitably used.

[0088] The first electrode 101 reflects 40% or more, preferably 70% or more, of visible light. It is preferable that an electrode is included. Also, the second electrode 102 has a visible light reflectance of 20%. It is preferable that the electrode is semi-transparent and semi-reflective with a transparency of up to 80%, preferably 40% to 70%. Having such a configuration, the light-emitting device of one aspect of the present invention has a second electrode 1 It becomes a top-emission type light-emitting device that emits light from the 02 side, and the EL layer thickness By adjusting this, it is possible to create a light-emitting device with a microcavity structure. ru.

[0089] In this case, the interface on the EL layer 103 side of the reflective electrode and the reflective electrode of the first hole transport layer 112-1 The optical distance to the interface on the pole side is preferably λ / 8 to 3λ / 8. Also, the light-emitting layer 1 The optical distance between the 13 main light-emitting regions and the interface of the first hole transport layer 112-1 on the reflective electrode side. It is preferable that the value is 3λ / 8 to 5λ / 8. Also, the boundary on the EL layer 103 side of the reflective electrode The optical distance between the surface and the interface on the reflecting electrode side of the third hole transport layer 112-3 is 3λ / 8 to 5 It is preferable that λ / 8. Also, the main light-emitting region of the light-emitting layer 113 and the third hole transport The optical distance between layer 112-3 and the interface on the light-emitting layer side is preferably λ / 8 to 3λ / 8. i. With this configuration, the light reflected at the interface of each layer and the reflective electrode is amplified. As a result, it becomes possible to create a light-emitting device that is efficient and has good color purity. If it is difficult to accurately determine the main light-emitting region of the light-emitting layer, the transportability of the light-emitting layer should be considered. You can then set the estimated position as the basis.

[0090] By the way, in one aspect of the present invention, by stacking multiple hole transport layers with different refractive indices, light is obtained While improving emission efficiency, it also involves more layers than typical light-emitting devices. As it becomes a light-emitting device, the number of layer interfaces increases, making it easier for interface-derived resistance to occur during operation. There were instances where the voltage would rise.

[0091] Typically, in the hole transport region of organic semiconductor devices, considering the exchange of holes with the electrodes, active Holes are sequentially placed in a layer consisting of an organic compound having different HOMO levels from the layer or the luminescent layer. Next, injection is necessary. Naturally, if the difference in HOMO levels between each layer is too large, the drive will fail. Because the voltage becomes high, the HOMO levels between the electrode and the active layer (luminescent layer) By arranging a layer consisting of organic compounds having HOMO levels located in between, HOM This mitigates the difference in O levels. However, this is not the case for layers where the difference in HOMO levels is not very large. However, depending on the combination of organic compounds used, the driving voltage may increase significantly. Yes, it did. Until now, there were no guidelines to avoid it, and it was simply dismissed as a matter of compatibility between materials. They're here.

[0092] On the other hand, organic compounds include polar molecules and nonpolar molecules. Polar molecules are permanent dipole moments. Although it has a polarity, if polar molecules are deposited, and the deposited film is randomly oriented, these polarities The bias in polarity cancels out, and no polarization originating from molecular polarity occurs within the film. However, the deposition process is as described above. When a film has molecular orientation, a giant surface potential (Giant Surf) arises from the polarization bias. Ace Potential may appear.

[0093] Giant surface potential is a phenomenon in which the surface potential of a deposited film increases in proportion to its film thickness, and is particularly relevant for organic compounds. This phenomenon of spontaneous orientation polarization occurs when the permanent dipole moment is slightly biased in the direction of film thickness. This can be explained. In order to treat its size as a value independent of film thickness, the surface potential of the deposited film is The value obtained by dividing by the film thickness, that is, the potential gradient (slope) of the surface potential of the deposited film, should be used. In this document, the potential gradient of the surface potential of this deposited film will be referred to as GSP (mV / nm).

[0094] By taking this GSP value into consideration, the compatibility of conventional materials as described above is not considered to be mismatched. This eliminates the problem and makes it possible to easily obtain organic semiconductor devices with good characteristics.

[0095] In one aspect of the present invention, the GSP of the first hole transport layer 112-1 is transported to the third hole transport layer 112 The value obtained by subtracting GSP of -3 (ΔGSP) 1-3 It is preferable that the value is 10 (mV / nm) or less. Furthermore, it is more preferable that it be 0 (mV / nm) or less. Also, the second hole transport layer 112 The value obtained by subtracting the GSP of the third hole transport layer 112-3 from the GSP of -2 (ΔGSP) 2-3 )but It is preferable that the value be 10 (mV / nm) or less, and more preferable that it be 0 (mV / nm) or less. Preferred. Also, ΔGSP1-3 and ΔGSP 2-3 Both are 10 (mV / nm) or less. It is more preferable that the value is 0 (mV / nm) or less.

[0096] Furthermore, the GSP from the first hole transport layer 112-1 to the GSP of the second hole transport layer 112-2 Subtracted value (ΔGSP 1-2 It is preferable that )) is 10 (mV / nm) or less, and 0 (m It is even more preferable that the value be less than or equal to V / nm.

[0097] This configuration allows for a low drive voltage, low power consumption, or high power consumption. This will make it possible to easily obtain light-emitting devices with high efficiency and excellent characteristics.

[0098] Furthermore, the GSP of the third hole transport layer 112-3 is greater than the GSP of the first hole transport layer 112-1. It is also preferable that the GSP of the third hole transport layer 112-3 is higher than that of the second hole transport layer It is preferable that it is higher than the GSP of 112-2. Note that the G of the third hole transport layer 112-3 SP is from the first hole transport layer 112-1, the second hole transport layer 112-2, and both GSPs It is more preferable that the power consumption is also high. Having this configuration results in a lower drive voltage and a lower power consumption. To obtain a light-emitting device with good characteristics such as low power consumption or high power efficiency. can.

[0099] Furthermore, the GSP of the second hole transport layer 112-2 is the same as that of the first hole transport layer 112-1. It is preferable that it is higher than GSP. By having this configuration, the drive voltage is small, To obtain a light-emitting device with good characteristics such as low power consumption or high power efficiency. This becomes easier.

[0100] The GSP of each layer is measured by the GSP of the vapor-deposited film of the material (organic compound) that constitutes each layer. This can be determined by doing so.

[0101] This section explains how to determine the GSP (Global Spread Spectrum) of organic compounds.

[0102] Generally, when the surface potential of a deposited film measured by a Kelvin probe is plotted in the direction of film thickness, The slope is discussed as the magnitude of the giant surface potential, i.e., GSP (mV / nm). However, when two different layers are stacked, the polarization charge density (mC / m) accumulated at the interface 2 The GSP can be estimated by utilizing the fact that ) changes in relation to the GSP.

[0103] Non-patent document 1 describes organic thin films with different spontaneous polarizations (thin film 1 and thin film 2; however, thin film 1) When the film 1 is positioned as the anode and the thin film 2 as the cathode, and current is passed through them, the following equation holds true. It is indicated that it should stand.

[0104]

number

[0105]

number

[0106] In equation (1), σ if V is the polarization charge density. i V is the hole injection voltage. bi d is the threshold voltage, 2 is the thickness of the thin film 2, and ε2 is the dielectric constant of the thin film 2. i , V bi The device's capacitance-voltage It can be estimated from its properties. Furthermore, the dielectric constant is the refractive index n. o (633nm) squared It can be used. In this way, V estimated from the capacitance-voltage characteristics i , V bi And refraction From the dielectric constant ε2 of thin film 2 and the film thickness d2 of thin film 2 calculated from the ratio, the division is performed using equation (1). polar charge density σ if It is possible to find this.

[0107] Next, in equation (2), σ if P is the polarization charge density. n This is the GSP of thin film n, ε n is a thin film This is the dielectric constant of n. Here, from equation (1) above, the polarization charge density σ if It is possible to find out Therefore, by using a material with a known GSP as thin film 2, the GSP of thin film 1 can be estimated. It is possible.

[0108] As described above, the vapor-deposited film of the organic compound for which we want to determine the GSP is set to thin film 1 and the GSP is determined by the above method. We can find P.

[0109] In this specification, thin film 2 is known to be Al with a GSP of 48 (mV / nm). Using q3, the GSP of each thin film was determined.

[0110] Furthermore, it is known that the orientation of the deposited film depends on the substrate temperature during deposition, and the GSP value is also related to this. The results may depend on the substrate temperature during deposition. The measurements in this specification depend on the substrate temperature during deposition. The temperature of the film deposited at room temperature is used.

[0111] Next, examples of other structures and materials for a light-emitting device according to one aspect of the present invention will be described. A light-emitting device according to one aspect of the invention, as described above, has a first electrode 101 and a second electrode 102 The pair of electrodes has an EL layer 103 consisting of multiple layers, and the EL layer 103 consists of at least Both the light-emitting layer 113 and the hole transport layer 112 (first hole transport layer 112-1) are made of light-emitting material. It has a second hole transport layer 112-2 and a third hole transport layer 112-3.

[0112] The first electrode 101 is made of a metal, alloy, or conductive material with a large work function (specifically, 4.0 eV or more). It is preferable to form them using chemical compounds and mixtures thereof. Specifically, for example, For example, indium tin oxide (ITO), silica Indium oxide-tin oxide and indium oxide-zinc oxide containing silicon dioxide or silicon dioxide. Examples include indium oxide (IWZO) containing tungsten oxide and zinc oxide. These conductive metal oxide films are usually deposited by sputtering, but sol-ge It is also acceptable to use methods such as the 2000-2000 method for fabrication. Zinc is used in a target where 1-20 wt% zinc oxide is added to indium oxide. Methods include forming by the puttering method. Additionally, tungsten oxide and zinc oxide are used. The contained indium oxide (IWZO) has a ratio of 0.5% to tungsten oxide relative to indium oxide. Sputtering is performed using a target containing 5-5 wt% zinc oxide and 0.1-1 wt% zinc oxide. It can also be formed by law. In addition, the material used for the first electrode 101 is, for example, Gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr) ), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (P d) or nitrides of metallic materials (e.g., titanium nitride), etc. Or, the first electric Graphene can also be used as a material for pole 101. The composite material is in contact with the first electrode 101 in the EL layer 103 (typically the hole injection layer 11) By using method 1), it becomes possible to select electrode materials regardless of the work function. .

[0113] Furthermore, the first electrode 101 was formed of a material that is transparent to the light emitted by the light-emitting device. In this case, the light-emitting device will emit light from the first electrode 101 side, as shown in Figure 1(C). This is possible. In addition, the first electrode 101 has reflectivity to the light emitted by the light-emitting device. It includes an electrode, and the second electrode 102 is transparent to the light emitted by the light-emitting device. When formed from a material, light is emitted from the second electrode 102 side as shown in Figure 1(D). It can be used as an optical device. The hole transport layer 112 is connected to the light-emitting layer 113 and the first electrode 101 Since it is provided between them, the first electrode 101 is in response to the light emitted by the light-emitting device. It is preferable that the electrode contains a reflective electrode.

[0114] The EL layer 103 preferably has a laminated structure, but the laminated structure is as described above. Aside from the light-emitting layer 113 and the hole transport layer 112, there are no particular limitations, such as the hole injection layer, electron transport layer, and electron Injection layer, carrier block layer (hole block layer, electron block layer), exciton block layer, Various functional layers can be used, such as intermediate layers and charge generation layers. It does not have to be kicked. In this embodiment, as shown in Figure 1(A), the light-emitting layer 113, In addition to the hole transport layer 112, there is also the hole injection layer 111, the electron transport layer 114, and the electron injection layer 1 A configuration having 15, and as shown in Figure 1(B), instead of the electron injection layer 115 described above, Two types of configurations having a charge generation layer 116 will be described.

[0115] The hole injection layer 111 is provided in contact with the first electrode 101 and injects holes into the EL layer 103. It has the function of making it easier. The hole injection layer 111 is made of phthalocyanine (abbreviated as H2Pc) and copper. Phthalocyanine-based complex compounds such as phthalocyanine (abbreviated as CuPc), 4,4'-bis [N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: D PAB), 4,4'-bis(N-{4-[N'-(3-methylphenyl)-N'-phenyl Aromas such as [N-phenylamino]biphenyl (abbreviated as DNTPD) Group amine compounds, or poly(3,4-ethylenedioxythiophene) / poly(styrene) It can be formed by polymers such as sulfonic acid (PEDOT / PSS).

[0116] Furthermore, the hole injection layer 111 may be formed from a material having acceptor properties. Substances exhibiting this property include organic compounds containing electron-withdrawing groups (halogen groups, cyano groups, etc.). It can be used, and 7,7,8,8-tetracyano-2,3,5,6-tetrafluoro Kinodimethane (abbreviation: F4-TCNQ), chloranil, 2,3,6,7,10,11-H Xacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-C) N), 1,3,4,5,7,8-Hexafluorotetracyano-naphthoquinodimethane (abbreviated) Name: F6-TCNNQ), 2-(7-dicyanomethylene-1,3,4,5,6,8,9, Examples include 10-octafluoro-7H-pyrene-2-ylidene)malononitrile. Yes, it is possible. In particular, electron-withdrawing groups can be attached to condensed aromatic rings that have multiple complex atoms, such as HAT-CN. The compound being combined is preferably thermally stable. Also, electron-withdrawing groups (especially fluoro groups) Radialene derivatives having halogen groups, cyano groups, etc. [3] have electron-accepting properties It is always preferable because it is high, specifically α,α',α''-1,2,3-cyclopropanetri Iridentris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile] ],α,α',α''-1,2,3-cyclopropanetriylidentris[2,6-dicy [LOLO-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], α ,α',α''-1,2,3-cyclopropanetriylidentris[2,3,4,5,6 Examples include pentafluorobenzeneacetonitrile. In terms of quality, in addition to the organic compounds mentioned above, there are also molybdenum oxide, vanadium oxide, and Thenium oxide, tungsten oxide, manganese oxide, etc. can be used. A material with ptogenic properties allows electricity to flow from the adjacent hole transport layer (or hole transport material) between the electrodes. Electrons can be extracted by applying pressure.

[0117] Furthermore, the hole injection layer 111 comprises a material having acceptor properties and a material having hole transport properties. It may also be formed from a composite material containing the following. For example, aromatic amine compounds, heteroaromatic compounds, aromatic hydrocarbons, polymer compounds (oligo Various organic compounds can be used, such as mers, dendrimers, polymers, etc. As for hole transport materials used in composite materials, 1 × 10 -6 cm 2 / Vs or higher It is preferable that the material has hole mobility. The material is a compound having a condensed aromatic hydrocarbon ring or a π-electron-rich heteroaromatic ring. It is preferable that the condensed aromatic hydrocarbon ring is an anthracene ring, a naphthalene ring, etc. Preferred. Also, as π-electron-rich heteroaromatic rings, the pyrrole skeleton, the furan skeleton, and thiof are preferred. A condensed aromatic ring containing at least one of the ene skeletons in the ring is preferred, specifically a carbazole ring, A dibenzothiophene ring or a ring formed by the condensation of a dibenzothiophene ring or a heteroaromatic ring is preferred. It seems so.

[0118] Materials with such hole transport properties include carbazole skeletons, dibenzofuran skeletons, It is more preferable to have either a dibenzothiophene skeleton or an anthracene skeleton. In particular, aromatic compounds having substituents containing a dibenzofuran ring or a dibenzothiophene ring. Amines, aromatic monoamines having a naphthalene ring, or 9-fluorenyl groups containing allile It may also be an aromatic monoamine that is bonded to the nitrogen of the amine via a nucleotide group. The material having pore transport properties is a substance having an N,N-bis(4-biphenyl)amino group. This is preferable because it allows for the creation of light-emitting devices with a good lifespan. Examples of transportable materials include N-(4-biphenyl)-6,N-diphenyl Rubenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), N, N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan 8-amine (abbreviation: BBABnf), 4,4'-bis(6-phenylbenzo[b]naphtho [1,2-d]furan-8-yl)-4''-phenyltriphenylamine (abbreviation: Bn fBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]f Ran-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)bene Zo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf(8)), N, N-bis(4-biphenyl)benzo[b]naphtho[2,3-d]furan-4amine (abbreviated) Name: 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 (abbreviated) Name: ThBA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenyl Amine (abbreviation: BBAβNB), 4-[4-(2-naphthyl)phenyl]-4',4'' -Diphenyltriphenylamine (abbreviation: BBAβNBi), 4,4'-diphenyl-4 ''-(6;1'-binaphthyl-2-yl)triphenylamine (abbreviation: BBAαNβN) B) 4,4'-diphenyl-4''-(7;1'-binaphthyl-2-yl)triphenyl Luamine (abbreviation: BBAαNβNB-03), 4,4'-diphenyl-4''-(7-F Phenyl)naphthyl-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4, 4'-Diphenyl-4''-(6;2'-Binaphthyl-2-yl)triphenylamine ( Abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-(7;2'-binaphthyl -2-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diph Phenyl-4''-(4;2'-binaphthyl-1-yl)triphenylamine (abbreviation: BB) AβNαNB), 4,4'-diphenyl-4''-(5;2'-binaphthyl-1-yl) Triphenylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenylyl)-4 '-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB) ), 4-(3-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-f Phenyltriphenylamine (abbreviation: mTPBiAβNBi), 4-(4-biphenylyl) -4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviated) Name: TPBiAβNBi), 4-phenyl-4'-(1-naphthyl)triphenylamine (Abbreviation: αNBA1BP), 4,4'-bis(1-naphthyl)triphenylamine (abbreviation :αNBB1BP), 4,4'-diphenyl-4''-[4'-(carbazole-9-I [YGTBi1BP]biphenyl-4-yltriphenylamine (abbreviation: YGTBi1BP), 4'-[ 4-(3-phenyl-9H-carbazole-9-yl)phenyl]tris(1,1'-bi Phenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carbamine) Zole-9-yl)biphenyl-4-yl]-4'-(2-naphthyl)-4''-pheni Triphenylamine (abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H- [Carbazole-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9 '-Spirobi[9H-fluorene]-2-amine (abbreviation: PCBNBSF), N,N-bi Su([1,1'-biphenyl]-4-yl)-9,9'-spirobi[9H-fluorene] -2-amine (abbreviation: BBASF), N,N-bis([1,1'-biphenyl]-4-amine) (Lu)-9,9'-spirobio[9H-fluorene]-4-amine (abbreviation: BBASF(4)) ), N-(1,1'-biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluor) Len-2-yl)-9,9'-spirobio[9H-fluorene]-4-amine (abbreviation: oF) BiSF), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluorene-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-phenyl Luolen-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3' -(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP) , 4-phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]trif Phenylamine (abbreviation: BPAFLBi), 4-phenyl-4'-(9-phenyl-9H- Carbazole-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-di Phenyl-4''-(9-phenyl-9H-carbazole-3-yl)triphenylamine n (abbreviation: PCBBi1BP), 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)triphenyl Luamine (abbreviation: PCBNBB), N-phenyl-N-[4-(9-phenyl-9H- Luvazole-3-yl)phenyl]-9,9'-spirobio[9H-fluorene]-2-a Min (abbreviation: PCBASF), N-(1,1'-biphenyl-4-yl)-N-[4-( 9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H- Fluoren-2-amine (abbreviation: PCBBiF), N,N-bis(9,9-dimethyl-9) H-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, N,N-bis(9, 9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren Examples include -1-amines.

[0119] Furthermore, as materials that possess hole transport properties, other aromatic amine compounds include N,N'- Di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPP) A) 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino] Biphenyl (abbreviation: DPAB), 4,4'-bis(N-{4-[N'-(3-methylphenyl [Nyl)-N'-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNTPD), 1,3,5-Tris[N-(4-diphenylaminophenyl)-N-Fe [Nylaminobenzene] (abbreviated as DPA3B), etc., can also be used. Furthermore, the first hole The organic compounds used in the transport layer 112-1 and the third hole transport layer 112-3 are preferably used. It is possible.

[0120] Furthermore, hole-transporting materials used in composite materials have a HOMO level of -5.7eV. It is even more preferable that the substance has a relatively deep HOMO level of -5.4 eV or lower. The hole-transporting material used in composite materials has a relatively deep HOMO level. This facilitates the injection of holes into the hole transport layer 112, and also improves the lifespan of the luminescent data. It becomes easier to obtain a vise. Also, hole transport materials used in composite materials Because it is a material with a relatively deep HOMO level, hole induction is moderately suppressed. Furthermore, it can be used to create light-emitting devices with a longer lifespan.

[0121] Furthermore, alkali metal or alkaline earth metal fluorides are preferably mixed into the above composite material. Alternatively, by increasing the atomic ratio of fluorine atoms in the layer to 20% or more, the refraction of the layer The ratio can be reduced. This also allows a layer with a lower refractive index to form inside the EL layer 103. This can be achieved, and the external quantum efficiency of light-emitting devices can be improved.

[0122] By forming the hole injection layer 111, the hole injection performance is improved, and the driving voltage is reduced. A light-emitting device can be obtained.

[0123] Furthermore, among substances with acceptor properties, organic compounds with acceptor properties are easily vapor-deposited. Because it is easy to form thin films on it, it is a readily usable material.

[0124] The hole transport layer 112 is formed by including a material that has hole transport properties. The materials are 1 x 10 -6 cm 2 It is preferable to have a hole mobility of / Vs or higher. The hole transport layer 112 of a light-emitting device according to one aspect of the present invention has the above-described configuration. This allows for the creation of a light-emitting device with good characteristics. For example, external quantum efficiency, current Efficiency, blue index, or one or more of these can make a light-emitting device a good one. If the above configuration is not applied, the hole transport layer 112 will consist of one or more layers. Materials that can transport holes can be used in the composite material of the hole injection layer. The materials listed as having good hole transport properties can be used.

[0125] An electron blocking layer may be provided between the hole transport layer 112 and the light-emitting layer 113. The electron blocking layer has hole transport properties and its LUMO level is 0.25 higher than that of the light-emitting layer 113. It is preferable to use a substance with an eV of 1 or more.

[0126] The light-emitting layer 113 preferably has a light-emitting substance and a host material. It may also contain other materials at the same time. Furthermore, it may be a laminate of two layers with different compositions. That's fine.

[0127] Whether the luminescent material is a fluorescent material or a phosphorescent material, it exhibits thermally activated delayed fluorescence (T The substance may be any other luminescent substance, even if it exhibits ADF (Active Deposition Factor). One embodiment is a layer that exhibits fluorescence emission, particularly a layer that exhibits blue fluorescence emission. It can be suitably applied depending on the circumstances.

[0128] In the light-emitting layer 113, possible materials that can be used as fluorescent light-emitting materials include, for example, Examples include those listed below. Other fluorescent materials can also be used.

[0129] 5,6-Bis[4-(10-phenyl-9-antryl)phenyl]-2,2'-bipyri Zin (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-antri [Lu)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N, N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl] )phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bi (3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluorene- 9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn) ), N,N'-bis[4-(9H-carbazole-9-yl)phenyl]-N,N'-di Phenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazo (Abbreviated) 4'-(10-phenyl-9-anthryl)triphenylamine ( Name: YGAPA), 4-(9H-carbazole-9-yl)-4'-(9,10-dife Nyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl Nyl-N-[4-(10-phenyl-9-antryl)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: PCBAP) A) 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'-to Riphenyl-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-(9,1 0-Diphenyl-2-anthryl)-N,9-Diphenyl-9H-carbazole-3-A Min (abbreviation: 2PCAPA), N-[9,10-bis(1,1'-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(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-tri Phenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis( 1,1'-biphenyl-2-yl)-N-[4-(9H-carbazole-9-yl) [Nyl]-N-phenylanthracene-2-amine (abbreviation: 2YGABPhA), N,N, 9-Triphenylanthracene-9-amine (abbreviation: DPhAPhA), Coumarin 545 T,N,N'-diphenylquinacridone (abbreviation: DPQd), rubren, 5,12-bis (1,1'-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT) ), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4 H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl -6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolidine] [-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: D CM2), N,N,N',N'-Tetrakis(4-methylphenyl)tetracene-5,1 1-Diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'- Tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluorantene-3,10 -Diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1 ,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij] [Quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (Abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7 Tramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolidine 9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DC JTB), 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-teto Lahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyra N-4-ylidene propanedinitrile (abbreviation: BisDCJ™), N,N'-diphosphate Nyl-N,N'-(1,6-pyrene-diyl)bis[(6-phenylbenzo[b]naphthate [1,2-d]furan)-8-amine](abbreviation: 1,6BnfAPrn-03), 3,1 0-Bis[N-(9-phenyl-9H-carbazol-2-yl)-N-phenylamino ]Naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10PCA2Nb f(IV)-02), 3,10-bis[N-(dibenzofuran-3-yl)-N-phenyl Luamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10Fr Examples include A2Nbf(IV)-02). In particular, 1,6FLPAPrn, 1,6m Pyridine compounds such as MemFLPAPrn and 1,6BnfAPrn-03 can be substituted. The condensed aromatic diamine compounds shown exhibit high hole-trapping properties and luminescence efficiency or reliability. It is preferable because it is superior in that respect.

[0130] In the light-emitting layer 113, if a phosphorescent material is used as the light-emitting material, it is possible to use it. Examples of suitable materials include the following:

[0131] 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-diphen) Iridium(III) (abbreviation: [Ir(Mpt) z)3]), Tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H -1,2,4-Triazolat] Iridium(III) (Abbreviation: [Ir(iPrptz-3 b)3)Organometallic iridium complexes having a 4H-triazole skeleton, or RIS[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4- Ryasolato Iridium (III) (abbreviation: [Ir(Mptz1-mp)3]), Tris (1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato)iridi 1H-triazole like um(III) (abbreviation: [Ir(Prptz1-Me)3]) iridium organometallic complexes having a rib skeleton, or fac-tris[(1-2,6-diiso [Propylphenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation) :[Ir(iPrpmi)3]), Tris[3-(2,6-dimethylphenyl)-7-methylphenyl] Chiruimidazo[1,2-f]phenantriginato]iridium(III)(abbreviation:[Ir Organometallic iridium with an imidazole skeleton, such as (dmpimpt-Me)3]). The complex or bis[2-(4',6'-difluorophenyl)pyridinate-N,C 2’ ] Iridium(III) tetrakis(1-pyrazolyl) borate (abbreviation: Fir6), bis [2-(4',6'-difluorophenyl)pyridinate-N,C 2’ Iridium (II) I) Picolinate (abbreviation: Firpic), Bis{2-[3',5'-Bis(trifluoro [methyl)phenyl]pyridinate-N,C 2’ Iridium(III) picolinate (abbreviated) Name: [Ir(CF3ppy)2(pic)]), bis[2-(4',6'-difluoroph Enyl)pyridinate-N,C 2’ Iridium(III) acetylacetonate (abbreviation: A phenylpyridine derivative having an electron-withdrawing group, such as FIr(acac), is used as a ligand. Examples include organometallic iridium complexes. These are compounds that exhibit blue phosphorescence. It is a compound that exhibits emission peaks in the wavelength range from 440 nm to 520 nm.

[0132] Also, tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)3]), Tris(4-t-butyl-6-phenylpyrimidinato)yli Dium(III) (abbreviation: [Ir(tBuppm)3]), (acetylacetonato)bis (6-methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mp) pm)2(acac)]), (acetylacetonato)bis(6-tert-butyl-4- Phenylpyrimidina) Iridium(III) (Abbreviation: [Ir(tBuppm)2(ac (ac)), (acetylacetonate)bis[6-(2-norbornyl)-4-phenylp Limiginato Iridium(III) (abbreviation: [Ir(nbppm)2(acac)]), (Acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenyl [Pyrimidinato] Iridium(III) (Abbreviation: [Ir(mpmppm)2(acac)] ), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(II) I) (abbreviation: [Ir(dppm)2(acac)]) has a pyrimidine skeleton iridium metal complex or (acetylacetonato)bis(3,5-dimethyl-2-filament Iridium(III) (Abbreviation: [Ir(mppr-Me)2(aca c)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenyl Pyrazinate) Iridium(III) (Abbreviation: [Ir(mppr-iPr)2(acac) ]) an organometallic iridium complex having a pyrazine skeleton, or tris(2-phenyl Lupiridina-N,C 2’ Iridium(III) (abbreviation: [Ir(ppy)3]), S(2-phenylpyridinato-N,C) 2’ Iridium(III) acetylacetonate (Abbreviation: [Ir(ppy)2(acac)]), Bis(benzo[h]quinolinato)iridi Um(III)acetylacetonate (abbreviation: [Ir(bzq)2(acac)]), 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) Cetylacetonate (abbreviation: [Ir(pq)2(acac)]), [2-d3-methyl- 8-(2-pyridinyl-κN)benzofloxacin [2,3-b]pyridinyl-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]benzofloxacin[2 ,3-b]pyridine-7-yl-κC]bis[5-(methyl-d3)-2-[5-(methyl [Lu-d3)-2-pyridinyl-κN]phenyl-κC]iridium(III) (abbreviation: I r(5mtpy-d6)2(mbfpypy-iPr-d4)),[2-d3-methyl- (2-pyridinyl-κN)benzofloxacin[2,3-b]pyridin-κC]bis[2-(2- Pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy)2( mbfpypy-d3)),[2-(4-methyl-5-phenyl-2-pyridinyl-κN )phenyl-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium( Organic compounds with a pyridine skeleton, such as III) (abbreviation: Ir(ppy)2(mdppy)) In addition to metallic iridium complexes, tris(acetylacetonate)(monophenanthroline) ter Rare earth metal complexes such as bium(III) (abbreviation: [Tb(acac)3(Phen)]) These are examples of compounds that primarily exhibit green phosphorescence, ranging from 500 nm to 6 It exhibits emission peaks in the wavelength range up to 00 nm. Furthermore, it possesses a pyrimidine skeleton. iridium metal complexes are particularly preferred because they also exhibit outstanding reliability and luminescence efficiency. .

[0133] Also, (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimid Sodium iridium(III) (abbreviation: [Ir(5mdppm)2(dibm)]), bis [4,6-Bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridi Um(III) (abbreviation: [Ir(5mdppm)2(dpm)]), bis[4,6-di( Naphthalene-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) Organometallic gold with a pyrimidine skeleton, such as (abbreviation: [Ir(d1npm)2(dpm)]) Iridium complexes of the genus, or (acetylacetonato)bis(2,3,5-triphenylpyra Dinato) Iridium(III) (abbreviation: [Ir(tppr)2(acac)]), Bis( 2,3,5-Triphenylpyrazinate)(dipivaloylmethanato) Iridium(III) (Abbreviation: [Ir(tppr)2(dpm)]), (acetylacetonato)bis[2,3- Bis(4-fluorophenyl)quinoxalinato] Iridium(III) (abbreviation: [Ir( Organometallic iridium complexes having a pyrazine skeleton such as Fdpq)2(acac)]) or is Tris(1-phenylisoquinolinato-N,C 2’ Iridium (III) (abbreviation) :[Ir(piq)3]), bis(1-phenylisoquinolinato-N,C 2’ ) Iridiu It is like (III) acetylacetonate (abbreviation: [Ir(piq)2(acac)]) In addition to organometallic iridium complexes having a pyridine skeleton, 2, 3, 7, 8, 12, 13, 1 7,18-Octaethyl-21H,23H-Porphyrin Platinum(II) (Abbreviation: PtOE) Platinum complexes such as P) or tris(1,3-diphenyl-1,3-propanediona) (Monophenanthroline) Europium (III) (Abbreviation: [Eu(DBM)3(Ph en)]), Tris[1-(2-tenoyl)-3,3,3-trifluoroacetonate]( Monophenanthroline) Europium(III) (Abbreviation: [Eu(TTA)3(Phen Examples include rare earth metal complexes such as ). These are compounds that exhibit red phosphorescence. It exhibits emission peaks in the wavelength range from 600 nm to 700 nm. Organometallic iridium complexes with a pyrazine skeleton produce a red emission with good chromaticity.

[0134] In addition to the phosphorescent compounds described above, other known phosphorescent compounds may be selected and used. .

[0135] TADF materials include fullerenes and their derivatives, acridines and their derivatives, and eosin. Derivatives can be used. Also, magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (P Examples of metal-containing porphyrins include those described in d). For example, the protoporphyrin-tin fluoride complex (SnF2(Pro to IX), mesoporphyrin-tin fluoride complex (SnF2(Meso IX)), Hematoporphyrin-tin fluoride complex (SnF2(Hemato IX)), copropol Filinetetramethyl ester-tin fluoride complex (SnF2(Copro III-4M) e) Octaethylporphyrin-tin fluoride complex (SnF2(OEP)), ethio Rufirin-tin fluoride complex (SnF2(Etio I)), octaethylporphyrin - Examples include platinum chloride complexes (PtCl2OEP), etc.

[0136] [ka]

[0137] Furthermore, the following structural formula shows 2-(biphenyl-4-yl)-4,6-bis(12-) Enylindoro[2,3-a]carbazole-11-yl)-1,3,5-triazine( Abbreviation: PIC-TRZ) or 9-(4,6-diphenyl-1,3,5-triazine- 2-yl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCC) zTzn), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H [carbazole-9-yl]phenyl]-4,6-diphenyl-1,3,5-triazine (Abbreviation: PCCzPTzn), 2-[4-(10H-phenoxazine-10-yl)phen [Nyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3- [4-(5-phenyl-5,10-dihydrophenazine-10-yl)phenyl]-4, 5-Diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9 -dimethyl-9H-acridine-10-yl)-9H-xanthene-9-one (abbreviation: A CRXTN), bis[4-(9,9-dimethyl-9,10-dihydroacrylidine)phen [L]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiron [Acridine-9,9'-anthracene]-10'-one (abbreviation: ACRSA), etc. Heterocyclic compounds having one or both of an electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring. These can also be used. The heterocyclic compound is a π-electron-rich heteroaromatic ring and a π-electron-deficient heterocyclic ring. Because it has an aromatic ring, it has high electron transport and hole transport properties, which is desirable. In particular, π-electron Among skeletons having a deficient heteroaromatic ring, pyridine skeleton, diazine skeleton (pyrimidine skeleton) The pyrazine skeleton, pyridazine skeleton, and triazine skeleton are stable and reliable. It is preferable. In particular, the benzoflopyrimidine skeleton, the benzothienopyrimidine skeleton, and the benzoflopyrimidine skeleton are preferable. The lopyrazine and benzothienopyrazine skeletons have high acceptability and good reliability. Preferred. Also, among skeletons having a π-electron-rich heteroaromatic ring, the acridine skeleton and ferrous rings are preferred. Noxazine skeleton, phenothiazine skeleton, furan skeleton, thiophene skeleton, and pyrrole skeleton It is preferable that the structure has at least one of the components of the said framework, as it is stable and reliable. As for the furan skeleton, it is the dibenzofuran skeleton, and as for the thiophene skeleton, it is the dibenzothiophene The following skeletons are preferred. In addition, as for the pyrrole skeleton, the indole skeleton and carbazo are preferred. 3-(9-phenyl-9H) The -carbazole-3-yl)-9H-carbazole skeleton is particularly preferred. A substance in which a superfluous heteroaromatic ring and a π-electron-deficient heteroaromatic ring are directly bonded is a π-electron-rich heteroaromatic ring. The electron-donating properties of the aromatic ring and the electron-accepting properties of the π-electron-deficient heteroatomous ring are both strengthened, and the S1 level and T Because the energy difference between levels becomes smaller, thermally activated delayed fluorescence can be obtained efficiently. Particularly preferred. Note that instead of a π-electron-deficient heteroaromatic ring, an electron-withdrawing group such as a cyano group may be used. Aromatic rings bonded to them may also be used. In addition, as a π-electron-rich skeleton, an aromatic amine skeleton may be used. Phenazine skeletons and the like can be used. Also, xanthene skeletons can be used as π-electron-deficient skeletons. Tioxanthene dioxide skeleton, oxadiazole skeleton, triazole skeleton, imi Dazole skeleton, anthraquinone skeleton, phenylborane or volanthrene, and other boron-containing skeletons Aromatic rings having a nitrile group or cyano group, such as benzonitrile or cyanobenzene. Or heteroaromatic rings, carbonyl skeletons such as benzophenone, phosphine oxide skeletons, sulfonates A phono skeleton and the like can be used. In this way, a π-electron-deficient heteroaromatic ring and a π-electron-deficient heteroaromatic ring and Replace at least one of the extra-conjugated heteroaromatic rings with a π-electron-deficient skeleton and a π-electron-excess skeleton It can be used.

[0138] [ka]

[0139] Furthermore, as a TADF material, TA is a material in which the singlet excited state and the triplet excited state are in thermal equilibrium. DF materials may also be used. However, such TADF materials have a shorter luminescence lifetime (excitation lifetime). Therefore, the decrease in efficiency in the high-brightness region of the light-emitting element can be suppressed. Specifically, Examples of materials with molecular structures like those shown below include:

[0140] [ka]

[0141] TADF materials are characterized by a small difference between the S1 and T1 levels, and triple intersystem crossing occurs due to reverse intersystem crossing. A function that can convert energy from singlet excitation energy to singlet excitation energy. It is a material that possesses this property. Therefore, the triplet excitation energy is obtained by a small amount of thermal energy. Upconversion to the multiplet excitation energy (reverse intersystem crossing) is possible, and the singlet excited state can be efficiently converted. It can be generated easily. Furthermore, the triplet excitation energy can be converted into luminescence. .

[0142] Furthermore, an excited complex (exciplex) is formed by two different substances forming an excited state. Exciplex (also called 'x' or 'exciplex') is a state where the difference between the S1 level and the T1 level is extremely small. As a TADF material capable of converting triplet excitation energy to singlet excitation energy, It has the function of being functional.

[0143] Furthermore, phosphorescence observed at low temperatures (e.g., 77K to 10K) can be used as an indicator of the T1 level. A vector can be used. For TADF materials, the short-wavelength tail of its fluorescence spectrum is Draw a tangent line, and set the energy at the wavelength of the extrapolation line as the S1 level, and the phosphorescence spectrum When a tangent is drawn at the tail on the short wavelength side, and the energy at the wavelength of the extrapolation is taken as the T1 level, Preferably, the difference between S1 and T1 is 0.3 eV or less, and preferably 0.2 eV or less. And is even more preferable.

[0144] Furthermore, when using TADF material as a light-emitting material, the S1 level of the host material is the TADF material. It is preferable that the T1 level of the host material is higher than the S1 level of the TADF material. A higher rank is preferable.

[0145] The host material for the light-emitting layer is a material that has electron transport properties or a material that has hole transport properties. Various carrier transport materials, such as the TADF materials mentioned above, can be used.

[0146] Materials with hole transport properties include those with amine skeletons and π-electron-rich heteroaromatic ring skeletons. Organic compounds are preferred. For example, 4,4'-bis[N-(1-naphthyl)-N-phen [Nuamino]biphenyl (abbreviation: NPB), N,N'-bis(3-methylphenyl)-N, N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenyl Mino-biphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluorene -9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9- Phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-F Phenyl-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine ( Abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-cal Bazole-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthol (Tyl)-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-dimethylamine Tyl-N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl [Nyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9- Phenyl-9H-carbazole-3-yl)phenyl]-9,9'-spirobio[9H- Compounds having an aromatic amine skeleton, such as ruolene]-2-amine (abbreviated as PCBASF) Alternatively, 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-di( N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenyl) Phenyl)-9-phenylcarbazole (abbreviation: CzTP), 3,3'-bis(9-phenyl Compounds having a carbazole skeleton, such as 9H-carbazole (abbreviated as PCCP) The formula is 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene (Abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9) H-Fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-II) I) 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyl Compounds containing a thiophene skeleton, such as nyldibenzothiophene (abbreviation: DBTFLP-IV) Compound or 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzoph (Abbreviation: DBF3P-II), 4-{3-[3-(9-phenyl-9H-fluore) [Phenyl-9-yl]phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II) Examples include compounds having a furan skeleton such as ). Among the above, compounds having an aromatic amine skeleton Compounds containing or having a carbazole skeleton are reliable and correct. It is preferable because it has high pore transport properties and contributes to reducing the driving voltage. Also, in the hole transport layer 112 Organic compounds, as mentioned as examples of materials with hole transport properties, can also be used.

[0147] Examples of materials with electron transport properties include bis(10-hydroxybenzo[h]quinoli Sodium beryllium(II) (abbreviation: BeBq2), bis(2-methyl-8-quinolinolate) )(4-phenylphenolate)aluminum(III) (abbreviation: BAlq), bis(8- Quinolinolate) Zinc(II) (abbreviation: Znq), Bis[2-(2-benzoxazolyl) [Phenolate]zinc(II) (abbreviation: ZnPBO), bis[2-(2-benzothiazolyl) Metal complexes such as phenolate zinc(II) (abbreviation: ZnBTZ) or π-electron-deficient complexes Organic compounds having an aromatic ring are preferred. Organic compounds having a π-electron-deficient heteroaromatic ring and For example, 2-(4-biphenylyl)-5-(4-tert-butylphenyl)- 1,3,4-Oxadiazole (abbreviation: PBD), 3-(4-biphenylyl)-4-Fe Nyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TA) Z), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadia Zole-2-yl]benzene (abbreviation: 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), 2-[3-(dibenzothiophene-4-i Phenyl-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-I) I) 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (abbreviation: Organic compounds having an azole skeleton such as BzOs, 3,5-bis[3-(9H-carba Zole-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri [3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB), bathophenantho Phosphorus (abbreviation: Bphen), vasocuproine (abbreviation: BCP), 2,9-di(2-naph (Tyl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBphen), 2 ,2-(1,3-phenylene)bis[9-phenyl-1,10-phenanthroline](abbreviated) Organic compounds containing a heteroaromatic ring with a pyridine skeleton, such as (mPPhen2P), 2- [3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline ( Abbreviation: 2mDBTPDBq-II), 2-[3'-(dibenzothiophen-4-yl)bi Phenyl-3-yl dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq- II) 2-[3'-(9H-carbazol-9-yl)biphenyl-3-yl]diben Zo[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: 2 CzPDBq-III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibe Nzo[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(di [Benzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6m DBTPDBq-II), 9-[3'-(dibenzothiophen-4-yl)biphenyl- 3-yl]naphtho[1',2':4,5]fl[2,3-b]pyrazine (abbreviation: 9mDB) tBPNfpr), 9-[(3'-dibenzothiophen-4-yl)biphenyl-4-yl [Lu]naphtho[1',2':4,5]fl[2,3-b]pyrazine (abbreviation: 9pmDBtB) PNfpr), 4,6-bis[3-(phenanthren-9-yl)phenyl]pyrimidine (Abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phen [Lu]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-(1,1'-biphenyl- 4-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzo 3,2-d]pyrimidine (abbreviation: 8BP-4mDBtPBfpm), 3,8-bis[ 3-(dibenzothiophen-4-yl)phenyl]benzofl[2,3-b]pyrazine( Abbreviation: 3,8mDBtP2Bfpr), 4,8-bis[3-(dibenzothiophene-4- [Iyl)phenyl]-[1]benzofloflo[3,2-d]pyrimidine (abbreviation: 4,8mDBt P2Bfpm), 8-[3'-(dibenzothiophen-4-yl)(1,1'-biphenyl) (Lu-3-yl)Naphtho[1',2':4,5]Flo[3,2-d]pyrimidine (abbreviation: 8mDBtBPNfpm), 8-[(2,2'-binaphthalene)-6-yl]-4-[3 -(dibenzothiophen-4-yl)phenyl]-[1]benzofl[3,2-d]pyri Midine (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- (1,1'-biphenyl-3-yl)-4-[3,5-bis(9H-carbazole-9- Iyl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), 2, 6-Bis(4-naphthalene-1-ylphenyl)-4-[4-(3-pyridyl)phenyl ]pyrimidine (abbreviation: 2,4NP-6PyPPm), 4-[3,5-bis(9H-carba Zole-9-yl)phenyl]-2-phenyl-6-(1,1'-biphenyl-4-yl) ) Pyrimidine (abbreviation: 6BP-4Cz2PPm), 7-[4-(9-phenyl-9H- Luvazolin-2-yl)quinazolin-2-yl]-7H-dibenzo[c,g]carbazol Organic compounds having a diazine skeleton such as (abbreviation: PC-cgDBCzQz), 2-[( 1,1'-biphenyl)-4-yl]-4-phenyl-6-[9,9'-spirobio(9H -Fluorene)-2-yl]-1,3,5-triazine (abbreviation: BP-SFTzn), 2 -{3-[3-(benzo[b]naphtho[1,2-d]furan-8-yl)phenyl]phenyl Nyl-4,6-diphenyl-1,3,5-triazine (abbreviation: mBnfBPTzn), 2-{3-[3-(benzo[b]naphtho[1,2-d]furan-6-yl)phenyl]f phenyl-4,6-diphenyl-1,3,5-triazine (abbreviation: mBnfBPTzn- 02), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-3-yl) Luvazole-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviated) Name: PCCzPTzn), 9-[3-(4,6-diphenyl-1,3,5-triazine- 2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: m PCCzPTzn-02), 2-[3'-(9,9-dimethyl-9H-fluorene-2- [Iyl)-1,1'-biphenyl-3-yl]-4,6-diphenyl-1,3,5-triyl Zin (abbreviation: mFBPTzn), 5-[3-(4,6-diphenyl-1,3,5-tri [Zin-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]ca Luvasol (abbreviation: mINc(II)PTzn), 2-{3-[3-(dibenzothiophene (-4-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine ( Abbreviation: mDBtBPTzn), 2,4,6-tris(3'-(pyridine-3-yl)bif Enyl-3-yl)-1,3,5-triazine (abbreviation: TmPPPyTz), 2-[3- (2,6-dimethyl-3-pyridinyl)-5-(9-phenantrenyl)phenyl]-4 ,6-diphenyl-1,3,5-triazine (abbreviation: mPn-mDMePyPTzn), 11-(4-[1,1'-diphenyl]-4-yl-6-phenyl-1,3,5-tri Zin-2-yl)-11,12-dihydro-12-phenyl-indoro[2,3-a]ca Luvasol (abbreviation: BP-Icz(II)Tzn), 2-[3'-(triphenylene-2 -yl)-1,1'-biphenyl-3-yl]-4,6-diphenyl-1,3,5-tri Azine (abbreviation: mTpBPTzn), 9-[4-(4,6-diphenyl-1,3,5-to Liazin-2-yl)-2-dibenzothiophenyl]-2-phenyl-9H-carbazol (abbreviation: PCDBfTzn), 2-[1,1'-biphenyl]-3-yl-4-phenyl Ru-6-(8-[1,1':4',1''-terphenyl]-4-yl-1-dibenzoph Triazines such as lanyl-1,3,5-triazine (abbreviation: mBP-TPDBfTzn) Examples include organic compounds containing heteroaromatic rings with a diazine skeleton. Among those mentioned above, diazine skeleton Organic compounds containing heteroaromatic rings having a pyridine skeleton or containing heteroaromatic rings having a pyridine skeleton Organic compounds containing heteroaromatic rings with a triazine skeleton are highly reliable. Preferred. In particular, containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton. Organic compounds, including organic compounds containing heteroaromatic rings with a triazine skeleton, have high electron transport properties. This also contributes to reducing the drive voltage.

[0148] As for TADF materials that can be used as host materials, the previously mentioned TADF materials are... The same material can be used. When TADF material is used as the host material, TA The triplet excitation energy generated in the DF material is converted to a singlet excitation energy through reverse intersystem crossing. It is converted into a substance, and then energy is transferred to the light-emitting material, thereby increasing the luminescence efficiency of the light-emitting device. This can be achieved. At this time, the TADF material functions as an energy donor, and the luminescent substance It functions as an energy acceptor.

[0149] This is very effective when the above-mentioned light-emitting material is a fluorescent material. In order to obtain high luminescence efficiency, the S1 level of the TADF material is higher than the S1 level of the fluorescent material. It is preferable that the T1 level of the TADF material is higher than the S1 level of the fluorescent material. A high level is preferable. Therefore, the T1 level of the TADF material is the same as the T1 level of the fluorescent material. A higher value is preferable.

[0150] Furthermore, it exhibits emission at wavelengths that overlap with the wavelength of the lowest-energy absorption band of the fluorescent material. It is preferable to use a TADF material that exhibits fluorescence emission. This is preferable because the transfer of excitation energy to the material becomes smoother, and luminescence is obtained efficiently. stomach.

[0151] Furthermore, singlet excitation energy is efficiently generated from triplet excitation energy through reverse intersystem crossing. For this to occur, it is preferable that carrier recombination occurs in the TADF material. The triplet excitation energy generated by the DF material is transferred to the triplet excitation energy of the fluorescent material. It is preferable not to do so. To that end, the fluorescent material has a luminescent phosphodiolus ( It is preferable to have a protecting group around the skeleton that causes light emission. The protecting group is a π bond. Substituents that do not have a substituent are preferred, saturated hydrocarbons are preferred, specifically those having 3 to 10 carbon atoms. The alkyl group below, substituted or unsubstituted cycloalkyl groups with 3 to 10 carbon atoms, carbon Examples include trialkylsilyl groups with a number between 3 and 10, and it is even preferable if there are multiple protecting groups. Substituents that do not have a π bond have poor carrier transport function, therefore carrier transport And with little effect on carrier recombination, the luminescent phosphodiphorus of the TADF material and the fluorescent material The distance can be increased. Here, the luminescent group is the cause of light emission in a fluorescent substance. This refers to an atomic group (skeleton) that has such a structure. The luminescent group preferably has a skeleton with π bonds and contains an aromatic ring. It is preferable that it has a condensed aromatic ring or a condensed heteroaromatic ring. As condensed heteroaromatic rings, they include the phenanthrene skeleton, stilbene skeleton, acridone skeleton, and f Examples include the enoxazine skeleton and the phenothiazine skeleton. In particular, the naphthalene skeleton and anthracite. Cene skeleton, fluorene skeleton, chrysene skeleton, triphenylene skeleton, tetracene skeleton, pyrene n skeleton, perylene skeleton, coumarin skeleton, quinacridone skeleton, naphthobisbenzofuran skeleton Fluorescent materials having this property are preferred because they have a high fluorescence quantum yield.

[0152] When using a fluorescent material as the light-emitting material, the host material should have an anthracene skeleton. Materials that are suitable for this purpose are used as host materials for fluorescent materials. When used in this way, it is possible to realize a light-emitting layer with good luminescence efficiency and durability. Host material Substances having an anthracene skeleton that can be used as a material include diphenylanthracene skeletons, In particular, substances having a 9,10-diphenylanthracene skeleton are preferred because they are chemically stable. Furthermore, if the host material has a carbazole skeleton, hole injection and transport properties are enhanced. Therefore, it is preferable, but a benzocarbazole skeleton in which a benzene ring is further condensed on carbazole is preferable. When included, the HOMO becomes about 0.1 eV shallower than that of carbazole, making it easier for holes to enter. Therefore, it is preferable. In particular, when the host material contains a dibenzocarbazole skeleton, The HOMO becomes about 0.1 eV shallower than in zole, making it easier for holes to enter, and also for hole transport. It is also excellent in terms of properties and has high heat resistance, making it suitable. Therefore, it is even more suitable as a host material. What is interesting is the 9,10-diphenylanthracene skeleton and the carbazole skeleton (or It is a substance that simultaneously possesses a benzocarbazole skeleton or a dibenzocarbazole skeleton. Furthermore, from the viewpoint of hole injection and transport as described above, the carbazole skeleton has been replaced with benzofluorescein. A dibenzofluorene skeleton or a dibenzofluorene skeleton may also be used. Examples of such substances include 9 -phenyl-3-[4-(10-phenyl-9-antryl)phenyl]-9H-carb Zole (abbreviation: PCzPA), 3-[4-(1-naphthyl)-phenyl]-9-phenyl -9H-carbazole (abbreviation: PCPN), 9-[4-(10-phenyl-9-anthracol [Cenyl)phenyl]-9H-carbazole (abbreviation: CzPA), 7-[4-(10-phenyl] [nyl-9-anthryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: c gDBCzPA), 6-[3-(9,10-diphenyl-2-anthryl)phenyl]- Benzo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl- 10-{4-(9-phenyl-9H-fluoren-9-yl)biphenyl-4'-yl} Anthracene (abbreviation: FLPPA), 9-(1-naphthyl)-10-[4-(2-naphthyl [Phenyl]anthracene (abbreviation: αN-βNPAnth), 9-(1-naphthyl)- 10-(2-naphthyl)anthracene (abbreviation: α,βADN), 2-(10-phenyl (Anthracen-9-yl)dibenzofuran, 2-(10-phenyl-9-anthracenyl) -Benzo[b]naphtho[2,3-d]furan (abbreviation: Bnf(II)PhA), 9-(2 -Naphthyl)-10-[3-(2-naphthyl)phenyl]anthracene (abbreviation: βN-m βNPAnth), 1-[4-(10-[1,1'-biphenyl]-4-yl-9-an [Tracenyl)phenyl]-2-ethyl-1H-benzimidazole (abbreviation: EtBImP) Examples include BPhA, etc. In particular, CzPA, cgDBCzPA, 2mBnfPPA, PCzPA exhibits very good characteristics, making it a preferred choice.

[0153] Furthermore, the host material may be a mixture of multiple substances, and the mixed host material When used, a mixture of electron-transporting material and hole-transporting material is used. Preferably, by mixing an electron-transporting material with a hole-transporting material. Furthermore, the transport properties of the light-emitting layer 113 can be easily adjusted, and the recombination region can be easily controlled. This is possible. The weight ratio of the content of hole-transporting material to electron-transporting material is positive. The ratio of materials with pore transport properties to materials with electron transport properties should be 1:19 to 19:1.

[0154] Furthermore, phosphorescent materials can be used as part of the above-mentioned mixed materials. When using a fluorescent material as a light-emitting material, excitation energy is supplied to the fluorescent material. It can be used as an energy donor.

[0155] Furthermore, these mixed materials may form excited complexes. These excited complexes are luminescent substances. It forms an excited complex that emits light that overlaps with the wavelength of the lowest energy absorption band. By selecting the right combination, energy transfer becomes smoother, and luminescence is obtained more efficiently. This is preferable because it allows for a reduction in the drive voltage.

[0156] Furthermore, at least one of the materials forming the excitation complex may be a phosphorescent material. By doing so, the triplet excitation energy is efficiently converted to the singlet excitation energy through reverse intersystem crossing. It can be converted to -.

[0157] As a combination of materials that efficiently form excited complexes, HO is a material with hole transport properties. It is preferable that the MO level is above the HOMO level of the electron-transporting material. If the LUMO level of a material with electron-transporting properties is higher than or equal to the LUMO level of a material with electron-transporting properties Preferred. Note that the LUMO and HOMO levels of the material are controlled by cyclic voltammetry. From the electrochemical properties (reduction potential and oxidation potential) of the material measured by CV (coefficient of variation) It can be derived.

[0158] Furthermore, the formation of excited complexes is related to, for example, the emission spectrum of hole-transporting materials and electron-transporting properties. The emission spectrum of a material having the above properties, and the emission spectrum of a mixed film obtained by mixing these materials. In comparison, the emission spectrum of the mixed film is shifted to longer wavelengths than the emission spectra of each individual material. Alternatively, this can be confirmed by observing a phenomenon (which has a new peak on the longer wavelength side). Alternatively, transient photoluminescence (PL) and electron transport of materials with hole transport properties. The transient PL of materials possessing certain properties and the transient PL of a mixed film obtained by mixing these materials are compared, and the mixing The transient PL lifetime of the film has a longer lifetime component than the transient PL lifetime of each material, or a delayed lifetime component. This can be confirmed by observing differences in transient responses, such as an increase in the proportion of the time. Furthermore, the transient PL mentioned above can be interpreted as transient electroluminescence (EL). No. That is, transient EL for hole-transporting materials, transient E for electron-transporting materials. By comparing the transient EL of L and mixed films and observing the differences in transient response, Excitation complex formation can be confirmed.

[0159] The electron transport layer 114 is a layer containing a material that has electron transport properties. For example, the electron mobility at which the square root of the electric field strength [V / cm] is 600 is 1 × 10⁻⁶-6 cm 2 A material having an electron mobility of / Vs or higher is preferred. Note that electron transport is more important than hole transport. Other substances can be used if they have high efficacy. Organic compounds having a π-electron-deficient heteroaromatic ring are preferred. Examples of organic compounds having this feature include organic compounds containing a heteroaromatic ring having a polyazole skeleton. Compounds, organic compounds containing heteroaromatic rings with a pyridine skeleton, heteroaromatic rings with a diazine skeleton Organic compounds containing aromatic rings and organic compounds containing heteroaromatic rings having a triazine skeleton It is preferable to have one or more of these.

[0160] Specifically, the electron-transporting materials that can be used in the above electron transport layer are: -(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxa Diazole (abbreviation: PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-t ert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis [5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl] Benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazo [Il-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 2,2',2' -(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzoimidazo (Abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1 -phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), 4,4'-bi (5-methylbenzoxazole-2-yl)stilbene (abbreviation: BzOs), etc. Organic compounds having a zole skeleton, 3,5-bis[3-(9H-carbazole-9-yl) Phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[3-(3-pyridyl Phenylbenzene (abbreviation: TmPyPB), phenylbenzene (abbreviation: Bph) en), vasocuproine (abbreviation: BCP), 2,9-di(2-naphthyl)-4,7-di Phenyl-1,10-phenanthroline (abbreviation: NBphen), 2,2-(1,3-phen Phenylene)bis[9-phenyl-1,10-phenanthroline] (abbreviation: mPPhen2) Organic compounds containing a heteroaromatic ring having a pyridine skeleton such as P), 2-[3-(dibenzothi Offen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTP) DBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl ]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3' -(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoki Sarin (abbreviation: 2mCzBPDBq), 2-[4'-(9-phenyl-9H-carbazol) [Lu-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-II) I) 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quino Xaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(dibenzothiophene- 4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-I I) 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-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mP) nP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviated) Name: 4,6mDBTP2Pm-II), 4,6-bis[3-(9H-carbazole-9- [Iyl(phenyl)]pyrimidine (abbreviation: 4,6mCzP2Pm), 9,9'-[pyrimidine] -4,6-diylbis(biphenyl-3,3'-diyl)]bis(9H-carbazole) (Abbreviation: 4,6mCzBP2Pm), 8-(1,1'-biphenyl-4-yl)-4-[ 3-(dibenzothiophen-4-yl)phenyl]-[1]benzofl[3,2-d]p Limidine (abbreviation: 8BP-4mDBtPBfpm), 3,8-bis[3-(dibenzothio) Fen-4-yl)phenyl]benzofl[2,3-b]pyrazine (abbreviation: 3,8mDB) tP2Bfpr), 4,8-bis[3-(dibenzothiophen-4-yl)phenyl]- [1] Benzofloe[3,2-d]pyrimidine (abbreviation: 4,8mDBtP2Bfpm), 8 -[3'-(dibenzothiophen-4-yl)(1,1'-biphenyl-3-yl)] Futo[1',2':4,5]fl[3,2-d]pyrimidine (abbreviation: 8mDBtBPNf pm), 8-[(2,2'-binaphthalene)-6-yl]-4-[3-(dibenzothiophone) [phenyl-4-yl)phenyl]-[1]benzoflof[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-f Phenylpyrimidine (abbreviation: 2,6(NP-PPm)2Py), 6-(1,1'-biphenylpyrimidine) Nyl-3-yl)-4-[3,5-bis(9H-carbazole-9-yl)phenyl]- 2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), 2,6-bis(4-naph Talene-1-ylphenyl)-4-[4-(3-pyridyl)phenyl]pyrimidine (abbreviation) :2,4NP-6PyPPm),4-[3,5-bis(9H-carbazole-9-yl) Phenyl]-2-phenyl-6-(1,1'-biphenyl-4-yl)pyrimidine (abbreviation) :6BP-4Cz2PPm), 7-[4-(9-phenyl-9H-carbazole-2-I [Quinazolin-2-yl]-7H-dibenzo[c,g]carbazole (abbreviation: PC-c Organic compounds having a diazine skeleton such as gDBCzQz, 2-[(1,1'-biphenate [9,9'-Spirobi(9H-Fluorene)-2]-4-phenyl-6-[9,9'-Spirobi(9H-Fluorene)-2 -Il]-1,3,5-triazine (abbreviation: BP-SFTzn), 2-{3-[3-(Be Nzo[b]naphtho[1,2-d]furan-8-yl)phenyl]phenyl}-4,6-di Phenyl-1,3,5-triazine (abbreviation: mBnfBPTzn), 2-{3-[3-( Benzo[b]naphtho[1,2-d]furan-6-yl)phenyl]phenyl}-4,6- Diphenyl-1,3,5-triazine (abbreviation: mBnfBPTzn-02), 2-{4- [3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl] [Phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTz) n), 9-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl ]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTzn- 02), 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)-1,1'- Biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFB) PTzn), 5-[3-(4,6-diphenyl-1,3,5-triazine-2yl) [nyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]carbazole (abbreviation: mINc(II)PTzn), 2-{3-[3-(dibenzothiophen-4-yl)fer [nyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mDBtBP) Tzn), 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-phenantrenyl)phenyl]-4,6-diphenyl- 1,3,5-triazine (abbreviation: mPn-mDMePyPTzn), 11-(4-[1, 1'-Diphenyl]-4-yl-6-phenyl-1,3,5-triazine-2-yl)- 11,12-dihydro-12-phenyl-indro[2,3-a]carbazole (abbreviation: BP-Icz(II)Tzn), 2-[3'-(triphenylene-2-yl)-1,1' -Biphenyl-3-yl]-4,6-diphenyl'1,3,5-triazine (abbreviation: mT pBPTzn), 9-[4-(4,6-diphenyl-1,3,5-triazine-2-yl) )-2-dibenzothiophenyl]-2-phenyl-9H-carbazole (abbreviation: PCDB) fTzn), 2-[1,1'-biphenyl]-3-yl-4-phenyl-6-(8-[1 ,1':4',1''-terphenyl]-4-yl-1-dibenzofuranyl)-1,3, Organic compounds containing a triazine skeleton, such as 5-triazine (abbreviation: mBP-TPDBfTzn) Examples of compounds include organic compounds containing a heteroaromatic ring having a diazine skeleton. Organic compounds containing a heteroaromatic ring having a pyridine skeleton or a compound having a triazine skeleton Organic compounds containing aromatic rings are reliable and preferred. In particular, diazines (pyrimidium) Organic compounds containing a heteroaromatic ring having a triazine or pyrazine skeleton, or having a triazine skeleton Organic compounds containing heteroaromatic rings exhibit high electron transport properties and contribute to reducing drive voltage.

[0161] Furthermore, by using a material with low refractive index and electron transport properties in the electron transport layer 114, Furthermore, it becomes possible to obtain light-emitting devices with even better characteristics.

[0162] As for organic compounds with low refractive index and electron transport properties that can be used in electron transport layers, 1 A carbon having at least one six-membered heteroaromatic ring containing 3 to 1 nitrogen atoms, forming a ring. It has multiple aromatic hydrocarbon rings with prime numbers between 6 and 14, and of the multiple aromatic hydrocarbon rings, At least two are benzene rings, and the hydrocarbon groups that form bonds with sp3 hybrid orbitals are compound Organic compounds containing multiple components are preferred.

[0163] Furthermore, such organic compounds have sp3 hybridization relative to the total number of carbon atoms in the molecule. It is preferable that the proportion of the total number of carbon atoms forming bonds in the orbitals is between 10% and 60%. It is more preferable that the concentration is between 10% and 50%. Alternatively, such an organic compound may be 1 The integral of the signal less than 4 ppm obtained by measuring the organic compound in question using H-NMR. It is preferable that the value is at least half the integral value of a signal of 4 ppm or higher.

[0164] Furthermore, the molecular weight of the above-mentioned organic compound having electron transport properties is between 500 and 2000. Preferred. Furthermore, bonds are formed in all sp3 hybrid orbitals of the organic compound. The hydrocarbon group is bonded to the aromatic hydrocarbon ring having 6 to 14 carbon atoms that forms the above ring, It is preferable that the LUMO of the organic compound is not distributed on the aromatic hydrocarbon ring.

[0165] The following general formula (G e1 1) or (G e1 1 Organic compounds represented by -1) are preferred.

[0166] [ka]

[0167] In the formula, A represents a six-membered heteroaromatic ring containing 1 to 3 nitrogen atoms, such as a pyridine ring or a pyrimidine ring. A pyrazine ring, a pyridazine ring, or a triazine ring is preferred.

[0168] Also, R 200 These are hydrogen, alkyl groups having 1 to 6 carbon atoms, and alicyclic groups having 3 to 10 carbon atoms. It represents either a substituent represented by formula (G1-1) or a substituent represented by formula (G1-1).

[0169] R 201 ~R 215 At least one of them is a substituted phenyl group, and the others are each a phenyl group. In addition, hydrogen, C1 to C6 alkyl groups, C3 to C10 alicyclic groups, substitution or no substitution. Aromatic hydrocarbon groups with 6 to 14 carbon atoms forming a substituted ring, substituted or unsubstituted pyridyl It represents either the R group or the R group. 201 , R 203 , R 205 , R 206 , R 208 , R 210 , R 211 , R 213 and R 215 The substituent is preferably hydrogen. A phenyl group having one or two substituents, each substituent independently having a carbon number Forms 1 to 6 alkyl groups, 3 to 10 alicyclic groups, and substituted or unsubstituted rings. It is one of the aromatic hydrocarbon groups having 6 to 14 carbon atoms.

[0170] Note that the above general formula (G e1 1) The organic compound represented by the above is an alkyl group having 1 to 6 carbon atoms. It has multiple hydrocarbon groups selected from alicyclic groups having 3 to 10 carbon atoms, and the total number of carbon atoms in the molecule The proportion of the total number of carbon atoms forming bonds with sp3 hybrid orbitals is between 10% and 60%. That is the case.

[0171] Furthermore, the following general formula (G e1 2) Organic compounds are preferred.

[0172] [ka]

[0173] In the formula, Q 1 ~Q 3 Of these, 2 or 3 represent N, and Q 1 ~Q 3 Two of them are N In that case, the remaining 1 represents CH.

[0174] Also R 201 ~R 215 At least one of them is a substituted phenyl group, and the others are each Each independently includes hydrogen, C1 to C6 alkyl groups, C3 to C10 alicyclic groups, and substitutions. This refers to an unsubstituted ring-forming aromatic hydrocarbon group having 6 to 14 carbon atoms, or a substituted or unsubstituted pyramidal group. It represents either a lysyl group or one of the following. Note that R 201 , R 203 , R 205 , R 206 , R 20 8 , R 210 , R 211 , R 213 and R 215 It is preferably hydrogen. A phenyl group having a substitution group has one or two substituents, each substituent independently of carbon Forms alkyl groups with 1 to 6 prime numbers, alicyclic groups with 3 to 10 carbon atoms, and substituted or unsubstituted rings. It is one of the aromatic hydrocarbon groups having 6 to 14 carbon atoms.

[0175] Note that the above general formula (G e1 2) The organic compound represented is an alkyl group having 1 to 6 carbon atoms. It has multiple hydrocarbon groups selected from alicyclic groups having 3 to 10 carbon atoms, and the total number of carbon atoms in the molecule The proportion of the total number of carbon atoms forming bonds with sp3 hybrid orbitals is between 10% and 60%. It is preferable that this be the case.

[0176] Also, the above general formula (G e1 1) or (G e1 In the organic compound represented in 2), substitution A phenyl group having a group is given by the following formula (G e1 It is preferable that the group is represented by 1-2).

[0177] [ka]

[0178] In the formula, α represents a substituted or unsubstituted phenylene group, and is a meta-substituted phenylene group. This is preferable. Also, if the meta-substituted phenylene group has one substituent, the substituent It is preferable that the substituent is also substituted at the meta position. The substituent may be a C1 to C6 atom. It is preferably a lucyl group or an alicyclic group having 3 to 10 carbon atoms, and preferably a group having 1 to 6 carbon atoms. It is more preferably an alkyl group, and even more preferably a t-butyl group.

[0179] R 220 These are alkyl groups having 1 to 6 carbon atoms, alicyclic groups having 3 to 10 carbon atoms, or substituted groups. Alternatively, it represents an aromatic hydrocarbon group with 6 to 14 carbon atoms that forms an unsubstituted ring.

[0180] Furthermore, j and n represent 1 or 2. Note that if j is 2, multiple α are the same but different. It may be so. Also, if k is 2, multiple R 220 Whether they are the same or different Good. Also, R 220 It is preferably a phenyl group, and one of the two meta positions or Pheny having an alkyl group with 1 to 6 carbon atoms or an alicyclic group with 3 to 10 carbon atoms on both sides It is preferable that the phenyl group is at one or both of the two meta positions. The substituent is more preferably an alkyl group having 1 to 6 carbon atoms, and is a t-butyl group. It would be even better if it were the case that...

[0181] Organic compounds with electron transport properties as described above are found in the blue light emission region (455 nm to 465 nm). The normal refractive index at (below nm) is 1.50 or greater and 1.75 or less, or the refractive index is normally measured. The ordinary refractive index at 633 nm light used is 1.45 or more and 1.70 or less, and It is an organic compound with good electron transport properties.

[0182] Furthermore, when the above-mentioned organic compound having electron transport properties is used in the electron transport layer 114, the electron transport layer 114 preferably further contains a metal complex of an alkali metal or alkaline earth metal. It is a heterocyclic compound having a diazine skeleton, a heterocyclic compound having a triazine skeleton, Heterocyclic compounds with a lysine skeleton formed excited complexes with alkali metal organometallic complexes. Because the energy at the time is easily stabilized (the emission wavelength of the excited complex is easily lengthened), This is preferable in terms of lifespan. In particular, heterocyclic compounds having a diazine skeleton or triazine skeletons The heterocyclic compounds possessing these compounds have deep LUMO levels, making them suitable for energy stabilization of excited complexes. be.

[0183] Furthermore, the above alkali metal organometallic complexes are metal complexes of sodium or lithium. Preferably, the above alkali metal organometallic complex has a quinolinol skeleton. It is preferable to have a ligand. Furthermore, it is preferable to have an organometallic complex of the alkali metal. The body is preferably a lithium complex or a derivative thereof containing an 8-quinolinolate structure. Derivatives of lithium complexes containing an 8-quinolinolate structure include those having an alkyl group. Lithium complexes containing a quinolinolate structure are preferred, and those having a methyl group are particularly preferred. .

[0184] 8-Quinolinolatolithium, which has an alkyl group, is used as a metal complex with a low refractive index. This is possible. Specifically, wavelengths in the range of 455 nm to 465 nm in the thin film state. The ordinary refractive index for light is 1.45 to 1.70, and the ordinary refractive index for light with a wavelength of 633 nm. The refractive index can be between 1.40 and 1.65.

[0185] Specifically, examples of the above-mentioned metal complexes include, for instance, 8-hydroxyquinolinatolithium. Examples include (abbreviation: Liq), 8-hydroxyquinolinato-sodium (abbreviation: Naq), etc. This is possible. In particular, monovalent metal ion complexes, especially lithium complexes, are preferred. iq is more preferable. Furthermore, if the 8-hydroxyquinolinate structure is present, its methyl substitution is preferred. Use a modified form (e.g., 2-methyl substituted, 5-methyl substituted, or 6-methyl substituted). It is also preferable that the alkali has an 8-quinolinolate structure with an alkyl group at the 6-position. Using metal complexes has the effect of lowering the driving voltage of light-emitting devices.

[0186] Furthermore, the electron transport layer 114 has an electron mobility at which the square root of the electric field strength [V / cm] is 600. 1 x 10 -7 cm 2 / Vs or more 5×10 -5 cm 2 It is preferable that it is less than or equal to / Vs. The amount of electrons injected into the light-emitting layer is controlled by reducing the electron transportability in the electron transport layer 114. This allows the light-emitting layer to avoid an electron-excess state. This configuration allows for In particular, a hole injection layer is formed as a composite material, and the composite material has hole transport properties. The HOMO level is relatively deep, between -5.7eV and -5.4eV. It is particularly preferable when it is a material because it has a good lifespan. In this case, it has electron transport properties. The material used is preferably one whose HOMO level is -6.0 eV or higher.

[0187] Between the electron transport layer 114 and the second electrode 102, an electron injection layer 115 is provided, which is lithium fluoride. LiF (LiF), Cesium Fluoride (CsF), Calcium Fluoride (CaF2), 8-Hydrogen Alkali metals or alkaline earth metals such as xikinolinatolithium (abbreviation: Liq) A layer containing the genus or its compounds or complexes may be provided. The electron injection layer 115 is an electron Alkali metals or alkaline earth metals or their compounds in a layer made of transportable material A substance containing another substance or an electride may be used. Examples of electrides include: For example, this could be a substance obtained by adding a high concentration of electrons to a mixed oxide of calcium and aluminum. It can be done.

[0188] Furthermore, the electron injection layer 115 is made of a substance having electron transport properties (preferably a bipyridine skeleton). (An organic compound containing) the above alkali metal or alkaline earth metal fluoride in a microcrystalline state It is also possible to use a layer containing a concentration of 50 wt% or more. This layer is refraction Because it is a low-efficiency layer, it is possible to provide a light-emitting device with better external quantum efficiency. It becomes Noh.

[0189] Alternatively, a charge generation layer 116 may be provided instead of the electron injection layer 115 in Figure 1(A) (Figure 1 (B)) The charge generating layer 116 generates a charge on the layer in contact with the cathode side of the layer when an electric potential is applied to it. This refers to a layer that can inject electrons into the layer adjacent to the anode. (Charge generation layer 1) 16 includes at least a P-type layer 117. The P-type layer 117 is the hole injection layer 11 described above. It is preferable to form it using the composite materials listed as materials that can constitute 1. Furthermore, the P-type layer 117 is a film containing the acceptor material described above as a material constituting the composite material. It may also be constructed by laminating a film containing a hole transport material. By applying a potential to the P-type layer 117... Therefore, electrons are injected into the electron transport layer 114 and holes are injected into the second electrode 102, which is the cathode, and The optical device is working.

[0190] In addition to the P-type layer 117, the charge generation layer 116 also includes an electron relay layer 118 and an electron injection buffer. It is preferable that one or both of the layers 119 are provided.

[0191] The electron relay layer 118 contains at least an electron-transporting material, and the electron injection buffer layer 1 It has the function of preventing interaction between 19 and the P-type layer 117, thereby enabling smooth electron transfer. The LUMO level of the electron-transporting material contained in the relay layer 118 is in the P-type layer 117. The LUMO level of the acceptor material and the charge generation layer 116 in the electron transport layer 114 It is preferable that the LUMO level is between the LUMO level of the material contained in the contacting layer. Electron relay layer 11 Specific energy levels of the LUMO level in electron-transporting materials used in 8 The voltage should be -5.0 eV or higher, preferably -5.0 eV to -3.0 eV. As for electron-transporting materials used in the electron relay layer 118, phthalocyanine-based materials are used. It is preferable to use a material or a metal complex having a metal-oxygen bond and an aromatic ligand.

[0192] The electron injection buffer layer 119 contains alkali metals, alkaline earth metals, rare earth metals, and These compounds (alkali metal compounds (oxides such as lithium oxide, halides, and carbonates) (including carbonates such as thium or cesium carbonate), alkaline earth metal compounds (oxides, halos) Compounds of rare earth metals (including oxides, halides, and carbonates) or rare earth metal compounds (oxides, halides, and carbonates) It is possible to use materials with high electron injection capabilities, such as (including)).

[0193] Furthermore, the electron injection buffer layer 119 contains an electron transporting substance and a donor substance, and If performed, alkali metals, alkaline earth metals, and rare earth metals will be used as donor substances. , and these compounds (alkali metal compounds (oxides and halides such as lithium oxide) , including carbonates such as lithium carbonate or cesium carbonate), alkaline earth metal compounds (oxidation (including substances, halides, and carbonates), or compounds of rare earth metals (oxides, halides) In addition to carbonates, tetrathianaphthalene (abbreviation: TTN), nickelosene, and decane are also included. Organic compounds such as methyl nickerosene can also be used.

[0194] The materials that possess electron transport properties include the materials that make up the electron transport layer 114 as described above. It can be formed using a similar material. This material is an organic compound with a low refractive index. Therefore, by using it in the electron injection buffer layer 119, luminescence with good external quantum efficiency is achieved. You can obtain a device.

[0195] The material forming the second electrode 102 has a small work function (specifically, 3.8 eV or less). (Below) Metals, alloys, electrically conductive compounds, and mixtures thereof can be used. Specific examples of such cathode materials include lithium (Li) or cesium (Cs). Lucali metals, as well as magnesium (Mg), calcium (Ca), and strontium (Sr Elements belonging to Group 1 or Group 2 of the periodic table, such as (MgA) and alloys containing these elements. Rare earth metals such as (g, AlLi), europium (Eu), ytterbium (Yb), and Examples include alloys containing these. However, between the second electrode 102 and the electron transport layer By providing an electron injection layer, regardless of the magnitude of the work function, Al, Ag, ITO, Various conductive materials such as indium oxide-tin oxide containing silicon or silicon oxide are used. It can be used as electrode 102 of the second electrode.

[0196] Furthermore, if the second electrode 102 is formed from a material that is transparent to visible light, Figure 1(D) As shown, this light-emitting device can emit light from the cathode side. When the first electrode 101 is fabricated on the substrate side, a so-called top-emission type light-emitting device is produced. It can be used as a vice.

[0197] These conductive materials can be manufactured using dry methods such as vacuum deposition or sputtering, or by inkjet printing. It is possible to deposit films using methods such as spin coating. Furthermore, the sol-gel method can be used. It may be formed by a wet process, or it may be formed by a wet process using a paste of a metal material.

[0198] Furthermore, various methods can be used to form the EL layer 103, regardless of whether they are dry or wet methods. This can be done using methods such as vacuum deposition, gravure printing, offset printing, and screen printing. You may use methods such as printing, inkjet printing, or spin coating.

[0199] Furthermore, each electrode or layer described above may be formed using different film deposition methods.

[0200] The configuration of the layer provided between the first electrode 101 and the second electrode 102 is as described above. It is not limited to the above. However, the metal used in the light-emitting region and the electrode or carrier injection layer To suppress quenching caused by proximity, the first electrode 101 and the second electrode A configuration is preferred in which a light-emitting region is provided at a location away from pole 102 where holes and electrons recombine.

[0201] Furthermore, a hole transport layer or electron transport layer in contact with the light-emitting layer 113, particularly in the light-emitting layer 113, The carrier transport layer near the binding region suppresses energy transfer from excitons generated in the light-emitting layer. Therefore, the band gap is contained in the light-emitting material that makes up the light-emitting layer or in the light-emitting layer. The material is composed of a substance with a band gap larger than the band gap of the luminescent material. It is preferable.

[0202] Next, we have a light-emitting device (multilayer element, tandem element) with a configuration in which multiple light-emitting units are stacked. The form of the (also called the child) will be explained. This light-emitting device has multiple between the anode and the cathode. This is a light-emitting device having a light-emitting unit. One light-emitting unit is shown in Figure 1(A). It has a configuration almost identical to that of the EL layer 103. In other words, the tandem element has multiple light-emitting units A light-emitting device having a , the light-emitting device shown in Figure 1(A) or Figure 1(B) is 1 It can be described as a light-emitting device having two light-emitting units.

[0203] In a tandem element, a first light-emitting unit and a second light-emitting unit are placed between the anode and the cathode. The components are stacked, and a charge generation layer is placed between the first light-emitting unit and the second light-emitting unit. A is provided. The anode and cathode are the first electrode 101 and the second electrode in Figure 1(A), respectively. This corresponds to electrode 102, and the same method described in the explanation of Figure 1(A) can be applied. Furthermore, even if the first and second light-emitting units have the same configuration, they may have different configurations. It may be possible.

[0204] In a tandem element, the charge generation layer generates light when a voltage is applied to the anode and cathode. It has the function of injecting electrons into one unit and holes into the other light-emitting unit. When a voltage is applied such that the potential of the anode is higher than the potential of the cathode, the charge generation layer Whether it involves injecting electrons into the first light-emitting unit and injecting holes into the second light-emitting unit Yes.

[0205] The charge generation layer can be formed with the same configuration as the charge generation layer 116 described in Figure 1(B). Preferred. Composite materials of organic compounds and metal oxides have excellent carrier implantation and carrier transport properties. Because of this, low voltage and low current operation can be achieved. If the anode side is in contact with the charge generation layer, the charge generation layer is the hole injection layer of the light-emitting unit. Since it can also perform other functions, the light-emitting unit does not need to have a hole injection layer.

[0206] Furthermore, when an electron injection buffer layer 119 is provided in the charge generation layer of a tandem element, the electron The injection buffer layer 119 plays the role of an electron injection layer in the anode-side light-emitting unit, It is not always necessary to form an electron injection layer in the light-emitting unit on the pole side.

[0207] The above describes a tandem element having two light-emitting units, but what about three or more light-emitting units? The same method can be applied to tandem elements, which consist of stacked units. By arranging multiple light-emitting units between the electrodes separated by a charge generation layer, the current density can be reduced. It enables high-brightness light emission while maintaining the same performance, and also realizes a longer-lasting element. This makes it possible to create a light-emitting device that is mobile and consumes little power.

[0208] Furthermore, by making the light-emitting color of each light-emitting unit different, the entire light-emitting device... This allows you to obtain light emission of the desired color. For example, a light emission device having two light emission units In the vise, the first light-emitting unit emits red and green light, and the second light-emitting unit emits blue light. By obtaining color, it is also possible to obtain a light-emitting device that emits white light as a whole. be.

[0209] Furthermore, the EL layer 103 or the first light-emitting unit, the second light-emitting unit and charge generation described above Each layer or electrode, such as a layer, can be created using methods such as vapor deposition (including vacuum deposition) or droplet ejection (ink). It can be formed using methods such as the jet method, coating method, and gravure printing method. Furthermore, they include low molecular weight materials, medium molecular weight materials (including oligomers and dendrimers), or It may contain polymer materials.

[0210] Furthermore, this embodiment can be freely combined with other embodiments.

[0211] (Embodiment 2) This embodiment describes a light-emitting device using the light-emitting device described in Embodiment 1. ru.

[0212] In this embodiment, an active machine fabricated using the light-emitting device described in Embodiment 1 is used. The Trix-type light-emitting device will be explained using Figures 2(A) and 2(B). (A) is a top view showing the light-emitting device, and Figure 2(B) is a dashed line AB shown in Figure 2(A) and This is a cross-sectional view taken along the dashed line CD. This light-emitting device controls the light emission of the light-emitting device. These include the drive circuit section (source line drive circuit) 601, indicated by the dotted line, and the pixel section 602. It includes a drive circuit section (gate line drive circuit) 603. Also, 604 is a sealing substrate, 605 This is a sealing material, and the area inside the sealing material 605 is a space 607.

[0213] The routing wire 608 is input to the source line drive circuit 601 and the gate line drive circuit 603. FPC (Flexible Printed Circuit) is a wiring system for transmitting signals and serves as an external input terminal. (Input circuit) 609 receives video signals, clock signals, start signals, reset signals, etc. Receive. Note that only the FPC is shown in the diagram here, but this FPC has a print distribution A wire substrate (PWB) may be attached. The light-emitting device in this specification is a light-emitting device This includes not only the main unit but also the state in which the FPC or PWB is attached to it. ru.

[0214] Next, the cross-sectional structure will be explained using Figure 2(B). The drive circuit section is located on the element substrate 610. And a pixel section is formed, but here, the source line drive circuit 601 which is the drive circuit section and One pixel in the pixel section 602 is shown.

[0215] The element substrate 610 is a substrate made of glass, quartz, organic resin, metal, alloy, semiconductor, etc. FRP (Fiber Reinforced Plastics), PVF (Polyvinyl Fiber) Made using a plastic substrate made of fluoride, polyester, or acrylic resin. Just make it.

[0216] The structure of the transistor used in the pixel or driving circuit is not particularly limited. For example, reverse It may be a hoop-type transistor or a stagger-type transistor. Either a top-gate or bottom-gate transistor is acceptable. The semiconductor material used is not particularly limited; for example, silicon, germanium, silicon carbide, Gallium nitride and the like can be used. Alternatively, In-Ga-Zn metal oxides, etc. An oxide semiconductor containing at least one of indium, gallium, and zinc may also be used.

[0217] The crystallinity of semiconductor materials used in transistors is not particularly limited; amorphous semiconductors, Semiconductors with crystalline properties (microcrystalline semiconductors, polycrystalline semiconductors, single-crystal semiconductors, or those with a crystalline region in part) Any semiconductor having the properties of [the semiconductor] may be used. If a semiconductor having crystalline properties is used, transients may occur. This is preferable because it suppresses the deterioration of the stanic characteristics.

[0218] Here, in addition to the transistors provided in the above-mentioned pixels or driving circuits, there are also touch sensors, which will be described later. For semiconductor devices such as transistors used in applications like these, oxide semiconductors are preferred. It is preferable to use oxide semiconductors, which have a wider band gap than silicon. By using oxide semiconductors with a wider bandgap than silicon, transistors can be made The current in the "F" state can be reduced.

[0219] The above oxide semiconductor preferably contains at least indium (In) or zinc (Zn). It is also In-M-Zn oxides (where M is Al, Ti, Ga, Ge, Y, Zr, Sn, It is an oxide semiconductor containing an oxide (such as a metal like La, Ce, or Hf). It is preferable.

[0220] In particular, the semiconductor layer has multiple crystalline portions, and the c-axis of the crystalline portion is the surface on which the semiconductor layer is formed. Alternatively, an acid oriented perpendicular to the upper surface of the semiconductor layer and having no grain boundaries between adjacent crystalline regions. It is preferable to use a crystalline semiconductor film.

[0221] By using such materials as semiconductor layers, fluctuations in electrical properties are suppressed, resulting in high reliability. This makes it possible to create a transistor.

[0222] Furthermore, due to its low off-current, the transistor having the aforementioned semiconductor layer can be used to... This makes it possible to retain the charge stored in the capacity over a long period of time. By applying a generator to each pixel, the gradation of the image displayed in each display area is maintained while driving It also becomes possible to shut down the circuit. As a result, it is possible to realize electronic devices with extremely reduced power consumption. It can be expressed.

[0223] It is preferable to provide an undercoat to stabilize the characteristics of the transistor. The undercoat may be: Inorganic silicon oxide films, silicon nitride films, silicon oxide-nitride films, silicon nitride-oxide films, etc. It can be fabricated using an insulating film, either as a single layer or in a multilayer configuration. The underlayer is fabricated by sputtering. CVD (Chemical Vapor Deposition) method (Plasma CVD method) , thermal CVD method, MOCVD (Metal Organic CVD) method, ALD ( Formed using methods such as Atomic Layer Deposition, coating, and printing. Yes, it is possible. However, a base coat does not need to be applied unless necessary.

[0224] Note that FET623 is one of the transistors formed in the drive circuit section 601. Furthermore, the drive circuit is formed using various CMOS, PMOS, or NMOS circuits. This is sufficient. Furthermore, this embodiment shows a driver-integrated type in which the drive circuit is formed on the substrate. However, this is not always necessary, and the drive circuit can be formed externally rather than on the circuit board. .

[0225] Furthermore, the pixel section 602 includes a switching FET 611 and a current control FET 612 and its drive It is formed by a plurality of pixels, each including a first electrode 613 electrically connected to the rain. However, it is not limited to this, and can also be used as a pixel section combining three or more FETs and a capacitive element. good.

[0226] Furthermore, an insulator 614 is formed covering the end of the first electrode 613. Here, positive It can be formed by using a photosensitive acrylic resin film of a mold.

[0227] Furthermore, in order to ensure good coverage of the EL layer and other layers formed later, the upper end of the insulator 614 is Alternatively, a curved surface with curvature is formed at the lower end. For example, the material of the insulator 614 and When a positive-type photosensitive acrylic resin is used, the radius of curvature is only at the upper end of the insulator 614. It is preferable to have a curved surface having a thickness of 0.2 μm to 3 μm. Also, the insulating material 614 is used. Therefore, either a negative-type or positive-type photosensitive resin can be used.

[0228] An EL layer 616 and a second electrode 617 are formed on the first electrode 613, respectively. Here, the first electrode 613 functions as an anode. Materials that can be used as an anode As for the material, it is desirable to use a material with a high work function. For example, ITO film, or Silicon-containing indium tin oxide film, indium oxide containing 2-20 wt% zinc oxide In addition to single-layer films such as chromium film, titanium nitride film, chromium film, tungsten film, Zn film, and Pt film, silver Lamination with a film mainly composed of nitride, lamination with a titanium nitride film and a film mainly composed of aluminum, nitride Using a three-layer structure consisting of a titanium oxide film, a film mainly composed of aluminum, and a titanium nitride film. This is possible. Furthermore, a laminated structure results in low resistance as wiring and good ohmic contours. It can be removed and further used as an anode.

[0229] Furthermore, the EL layer 616 was coated using a vapor deposition method with a vapor deposition mask, an inkjet method, and a spin coating method. It is formed by various methods such as those described in Embodiment 1. The EL layer 616 is formed by the structure described in Embodiment 1. It contains [something].

[0230] Furthermore, the material used for the second electrode 617, which is formed on the EL layer 616, has a work function. Small materials (Al, Mg, Li, Ca, or alloys or compounds thereof (MgAg, It is preferable to use MgIn, AlLi, etc. When the second electrode 617 is penetrated, the second electrode 617 is made of a thin metal film. Alternatively, a thin film of alloy and a transparent conductive film (ITO, indioxin oxide containing 2-20 wt% zinc oxide) Lamination with silicon-containing indium tin oxide, zinc oxide (ZnO), etc. is used. It is preferable.

[0231] Furthermore, the first electrode 613, the EL layer 616, and the second electrode 617 form the shape of the light-emitting device. This has been accomplished. The light-emitting device is the light-emitting device described in Embodiment 1. The element is made up of multiple light-emitting devices, but in the light-emitting device of this embodiment This includes both the light-emitting device described in Embodiment 1 and light-emitting devices having other configurations. It is acceptable for them to be mixed together. In this case, in one embodiment of the present invention, the light-emitting device emits light of different wavelengths. Since a common hole transport layer can be used between light-emitting devices, the manufacturing process is simple. This allows for a cost-effective light-emitting device.

[0232] Furthermore, by bonding the sealing substrate 604 to the element substrate 610 with the sealing material 605, A light-emitting device is placed in the space 607 surrounded by the sub-substrate 610, the sealing substrate 604, and the sealing material 605. The structure is equipped with chair 618. Furthermore, the space 607 is filled with filler material. In addition to cases where an inert gas (such as nitrogen or argon) is filled, it is also filled with a sealing material. In some cases, a recess is formed in the sealing substrate and a desiccant is placed there to reduce the effects of moisture. This configuration is preferable because it can suppress deterioration.

[0233] Furthermore, it is preferable to use epoxy resin or glass frit for the sealing material 605. Furthermore, it is desirable that these materials be as impermeable to moisture and oxygen as possible. Furthermore, in addition to glass substrates or quartz substrates, FRP (F) can also be used as the material for the sealing substrate 604. Polyvinyl Fluoride (PVF), Reinforced Plastics ), a plastic substrate made of polyester or acrylic resin can be used. .

[0234] Although not shown in Figures 2(A) and 2(B), a protective film may be provided on the cathode. The film may be formed from an organic resin film or an inorganic insulating film. Also, the exposed part of the sealing material 605 A protective film may be formed to cover the surface of the pair of substrates. It can be installed to cover exposed sides, sealing layers, insulating layers, etc.

[0235] The protective film can be made of a material that is impermeable to impurities such as water. This effectively suppresses the diffusion of impurities such as these from the outside to the inside.

[0236] Materials that make up the protective film include oxides, nitrides, fluorides, sulfides, ternary compounds, and metals. Alternatively, polymers can be used, for example, aluminum oxide, hafnium oxide, etc. Phenium silicate, lanthanum oxide, silicon oxide, strontium titanate, tantalum oxide Titanium dioxide, zinc oxide, niobium oxide, zirconium oxide, tin oxide, yttrium oxide cerium oxide, scandium oxide, erbium oxide, vanadium oxide, or indi oxide Materials containing um, etc., or aluminum nitride, hafnium nitride, silicon nitride, tantalum nitride Titanium nitride, niobium nitride, molybdenum nitride, zirconium nitride, or gallium nitride, etc. Materials containing titanium and aluminum nitrides, acids containing titanium and aluminum oxides containing aluminum and zinc, sulfides containing manganese and zinc, cerium Sulfides containing erbium and strontium, oxides containing erbium and aluminum, Materials containing oxides including ttrium and zirconium can be used.

[0237] The protective film can be formed using a film deposition method that provides good step coverage. This is preferable. One such method is atomic layer deposition (ALD). There is a deposition method. Protecting materials that can be formed using the ALD method. It is preferable to use it in membranes. By using the ALD method, dense cracks or pinholes can be detected. It is possible to form a protective film with reduced defects or uniform thickness. Furthermore, it is possible to reduce the damage inflicted on the processed member when forming the protective film.

[0238] For example, by forming a protective film using the ALD method, a surface with a complex uneven shape or, A uniform and low-defect protective film can be formed on the top, sides, and back of the touch panel. Cut.

[0239] As described above, a light-emitting device fabricated using the light-emitting device described in Embodiment 1 is obtained. It is possible.

[0240] The light-emitting device in this embodiment uses the light-emitting device described in Embodiment 1. This makes it possible to obtain a light-emitting device with good characteristics. Specifically, the embodiment described in Embodiment 1. Because light-emitting devices have good luminous efficiency, it is possible to create light-emitting devices with low power consumption. ru.

[0241] Figures 3(A) and 3(B) show how color purity can be achieved by adding a colored layer (color filter), etc. An example of a light-emitting device with improved performance is shown. Figure 3(A) shows the substrate 1001 and the underlying insulating film 1002 , gate insulating film 1003, gate electrodes 1006, 1007, 1008, first interlayer insulating film 1020, second interlayer insulating film 1021, peripheral portion 1042, pixel portion 1040, drive circuit portion 1 041, Anodes 1024R, 1024G, 1024B of the light-emitting device, Partition 1025, EL Layer 1028, second electrode 1029 of the light-emitting device, sealing substrate 1031, sealing material 1032 These are illustrated in the diagrams.

[0242] Furthermore, Figure 3(A) shows the colored layers (red colored layer 1034R, green colored layer 1034G, blue The colored layer 1034B is provided on a transparent substrate 1033. Also, the black matrix 1 A 035 layer may be further provided. Transparent substrate 1 provided with a colored layer and a black matrix. 033 is aligned and fixed to substrate 1001. Note that the colored layer and black matrix Kus 1035 is covered with an overcoat layer 1036.

[0243] Figure 3(B) shows the colored layers (red colored layer 1034R, green colored layer 1034G, blue colored layer Example of forming layer 1034B) between the gate insulating film 1003 and the first interlayer insulating film 1020. This was shown. Thus, the colored layer is provided between the substrate 1001 and the sealing substrate 1031. That's good too.

[0244] Furthermore, in the light-emitting device described above, light is taken to the substrate 1001 side on which the FET is formed. Although a light-emitting device with a bottom-emission structure was used, the light emission was taken from the sealing substrate 1031 side. It can also be used as a light-emitting device with a projection structure (top emission type). A cross-sectional view of the light-emitting device is shown in Figure 4. In this case, the substrate 1001 is a substrate that does not transmit light. This can be done. Until the connecting electrode that connects the FET and the anode of the light-emitting device is fabricated, the bottle It is formed in the same way as a muemission-type light-emitting device. Then, the third interlayer insulating film 1037 is electrically... It is formed covering pole 1022. This insulating film may also play a planarization role. Third layer The interlayer insulating film 1037 may be made of the same material as the second interlayer insulating film 1021, as well as other known materials. It can be formed by [doing something].

[0245] The anodes 1024R, 1024G, and 1024B of the light-emitting device may also be cathodes. Furthermore, in the case of a top-emission type light-emitting device as shown in Figure 4, the anode is used as the reflective electrode. Preferably, the structure of the EL layer 1028 is described as the EL layer 103 in Embodiment 1. The structure will be as described above.

[0246] In the top emission structure shown in Figure 4, the colored layer (red colored layer 1034R, green colored layer) The sealing is performed using a sealing substrate 1031 having a color layer 1034G and a blue colored layer 1034B. This can be done. The encapsulation substrate 1031 has a black matrix positioned between the pixels. 1035 may be provided. Colored layer (red colored layer 1034R, green colored layer 1034G, The blue colored layer 1034B) or the black matrix 1035 is the overcoat layer 10 It may be covered by 36. Note that the sealing substrate 1031 is a light-transmitting substrate. Let's do it this way.

[0247] In top-emission type light-emitting devices, a microcavity structure can be suitably applied. A light-emitting device having a microcavity structure has one electrode including a reflective electrode, and the other This is obtained by using a semi-transparent / semi-reflective electrode for one of the electrodes. There is at least an EL layer between the pole and the surface, and there is at least an emissive layer that forms an emissive region. ru.

[0248] The reflective electrode has a visible light reflectance of 40% to 100%, preferably 70% to 100%. It is %, and its resistivity is 1 × 10⁻⁶. -2 Assume the membrane is less than Ωcm in diameter. Also, semipermeable... The semi-reflective electrode has a visible light reflectance of 20% to 80%, preferably 40% to 70%. , and its resistivity is 1 × 10 -2 Assume the membrane is less than Ωcm in diameter.

[0249] The light emitted from the light-emitting layer contained in the EL layer is reflected by the reflective electrode and the semi-transmitting / semi-reflective electrode. It is reflected and resonates.

[0250] The light-emitting device has a thickness of a transparent conductive film or the aforementioned composite material, carrier transport material, etc. By changing this, the optical distance between the reflective electrode and the semitransmissive / semi-reflective electrode can be altered. This enhances the light of resonant wavelengths between the reflective electrode and the semitransmissive / semi-reflective electrode, and It can attenuate light of wavelengths that do not vibrate.

[0251] Furthermore, the light reflected back by the reflective electrode (the first reflected light) is semi-transmitted from the light-emitting layer. • Because it causes significant interference with the light (first incident light) that directly enters the semi-reflecting electrode, the reflective electrode and The optical distance of the light-emitting layer is (2n-1)λ / 4 (where n is a natural number greater than or equal to 1, and λ is amplified). It is preferable to adjust the wavelength of the emitted light. By adjusting the optical distance, the first By aligning the phase of the reflected light and the first incident light, the light emitted from the light-emitting layer can be further amplified. ru.

[0252] Furthermore, even if the EL layer in the above configuration has a structure with multiple light-emitting layers, it may still be a single light-emitting layer The structure may also have the following characteristics, for example, in combination with the configuration of the tandem light-emitting device described above. Furthermore, multiple EL layers are provided in a single light-emitting device with a charge generation layer in between, and each EL layer This may also be applied to a configuration in which one or more light-emitting layers are formed.

[0253] Having a microcavity structure enhances the emission intensity in the front direction at specific wavelengths. This makes it possible to reduce power consumption. Furthermore, the four sub-colors red, yellow, green, and blue are used. In the case of a light-emitting device that displays images as is, in addition to the brightness enhancement effect of yellow light emission, all sub-pixels By applying a microcavity structure tailored to the wavelength of each color, a light-emitting device with excellent characteristics can be produced. It can be placed there.

[0254] The light-emitting device in this embodiment uses the light-emitting device described in Embodiment 1. This makes it possible to obtain a light-emitting device with good characteristics. Specifically, the embodiment described in Embodiment 1. Because light-emitting devices have good luminous efficiency, it is possible to create light-emitting devices with low power consumption. ru.

[0255] Up to this point, we have explained active-matrix light-emitting devices, but from here on we will discuss passive devices. A matrix-type light-emitting device will be described. Figures 5(A) and 5(B) illustrate the present invention. The passive matrix type light-emitting device fabricated using this method is shown. Figure 5(A) shows the light-emitting device. Figure 5(B) is a perspective view showing the position, and is a cross-sectional view obtained by cutting Figure 5(A) along the dashed line XY. In 5, an EL layer 955 is provided on the substrate 951 between the electrode 952 and the electrode 956. The end of electrode 952 is covered with an insulating layer 953. A partition layer 954 is provided there. The side walls of the partition layer 954 become closer to the substrate surface. It has a slope such that the distance between one side wall and the other side wall becomes narrower. In other words, a partition wall The cross-section of layer 954 in the short-side direction is trapezoidal, with the base (similar in direction to the plane direction of insulating layer 953) The side facing the insulating layer 953 (the side in contact with the insulating layer 953) faces the upper side (the same direction as the plane direction of the insulating layer 953). It is shorter than the side that does not come into contact with the insulating layer 953. In this way, by providing the partition layer 954 This prevents malfunctions of light-emitting devices caused by static electricity, etc. Furthermore, passive matrix Even in the S-type light-emitting device, the light-emitting device described in Embodiment 1 is used, and reliability This allows for a high-performance light-emitting device or a light-emitting device with low power consumption.

[0256] The light-emitting device described above consists of numerous tiny light-emitting devices arranged in a matrix. Because these can be controlled, it can be suitably used as a display device for representing images. It is a light-emitting device.

[0257] Furthermore, this embodiment can be freely combined with other embodiments.

[0258] (Embodiment 3) [Light-emitting device] The following describes another example of a light-emitting device according to one embodiment of the present invention using the above-mentioned light-emitting device, and how to manufacture it. I will explain the law.

[0259] Figure 14(A) shows a schematic top view of a light-emitting device 450 according to one embodiment of the present invention. Light-emitting device 45 0 represents the light-emitting device 110R that emits red light, the light-emitting device 110G that emits green light, and blue light. Each has multiple light-emitting devices 110B that exhibit color. In Figure 14(A), each light-emitting device To easily distinguish between the chairs, the labels R, G, and B are added to the light-emitting area of ​​each light-emitting device. Yes, they are.

[0260] Light-emitting devices 110R, 110G, and 110B are each They are arranged in a matrix. Figure 14(A) shows light-emitting devices of the same color arranged in one direction. This shows a row, or so-called stripe arrangement. Note that the arrangement method of the light-emitting devices is as follows: It is not limited to this; you may also apply arrangement methods such as delta arrangements, zigzag arrangements, or pentile arrangements. Columns can also be used.

[0261] Light-emitting devices 110R, 110G, and 110B are in the X direction They are arranged in that direction. Also, in the Y direction which intersects with the X direction, light-emitting devices of the same color are arranged. Yes, they are.

[0262] Light-emitting devices 110R, 110G, and 110B have the above configuration. It is a light-emitting device that has [the following characteristics].

[0263] Figure 14(B) is a schematic cross-sectional view corresponding to the dashed line A1-A2 in Figure 14(A). Figure 14(C) is a schematic cross-sectional view corresponding to the dashed line B1-B2.

[0264] Figure 14(B) shows the light-emitting device 110R, the light-emitting device 110G, and the light-emitting device This shows a cross-section of 110B. The light-emitting device 110R consists of a first electrode 101R and an EL layer 1 The light-emitting device 110G has 20R, an EL layer 121, and a second electrode 102. Electrode 101G, EL layer 120G, EL layer (electron injection layer) 115, and second electrode 102 The light-emitting device 110B includes a first electrode 101B, an EL layer 120B, and an EL layer 12 It has an EL layer 121 and a second electrode 102. The EL layer 121 and the second electrode 102 are light-emitting devices This is provided in common to 110R, light-emitting device 110G, and light-emitting device 110B. EL Layer 121 can also be called a common layer.

[0265] The EL layer 120R of the light-emitting device 110R has intensity in at least the red wavelength range. It has a light-emitting organic compound that emits light. The EL layer 12 of the light-emitting device 110G 0G has a luminescent organic compound that emits light having intensity in at least the green wavelength range. The EL layer 120B of the light-emitting device 110B has intensity in at least the blue wavelength range. It has a light-emitting organic compound that emits light. Light-emitting device 110R, light-emitting device 11 0G and the light-emitting device 110B are at least one of which is a light-emitting device according to one aspect of the present invention Yes, and preferably the light-emitting device is light-emitting device 110B.

[0266] EL layer 120R, EL layer 120G, and EL layer 120B are the light-emitting layer and hole transport layer, respectively. It has at least one layer, and in addition, an electron injection layer, an electron transport layer, a hole injection layer, and a carrier block layer. It may have one or more of the following: a block layer, an exciton blocking layer, etc. The EL layer 121 is A configuration without an optical layer is possible. The EL layer 121 is preferably an electron injection layer. Furthermore, if the electron transport layer also serves as the electron injection layer, the EL layer 121 is not provided. That's fine.

[0267] The first electrode 101R, the first electrode 101G, and the first electrode 101B each emit light. It is provided for each device. In addition, the second electrode 102 and the EL layer 121 are provided for each light-emitting device. It is provided as a continuous layer common to all chairs. Also, EL layer 120R, EL layer 120G , and the hole transport layer in EL layer 120B is interrupted between light-emitting devices with different emission colors. However, it is preferable that they have the same configuration.

[0268] A conductive material that is transparent to visible light is connected to either the first electrode 101 or the second electrode 102. An electrical film is used on one side, and a reflective conductive film is used on the other. The first electrode 101 is translucent, and the second By making electrode 102 reflective, a bottom-emission type display device can be created. Conversely, the first electrode 101 can be made reflective and the second electrode 102 can be made translucent. Therefore, it can be made into a top-emission type display device. By making both electrode 101 and the second electrode 102 transparent, a double-sided injection type (dual emission) is created. It can also be a display device (of the type of cushion). The light-emitting device according to one aspect of the present invention is a top It is suitable for emission-type light-emitting devices.

[0269] The ends of the first electrode 101R, the first electrode 101G, and the first electrode 101B are covered, An insulating layer 124 is provided. The edges of the insulating layer 124 are preferably tapered. It is fine. Furthermore, the insulating layer 124 may be omitted if it is not needed.

[0270] EL layer 120R, EL layer 120G, and EL layer 120B are located on the upper surface of the pixel electrode, respectively. It has a contact region and a region in contact with the surface of the insulating layer 124. Also, the EL layer 120R, The edges of EL layer 120G and EL layer 120B are located on the insulating layer 124.

[0271] As shown in Figure 14(B), between two EL layers in light-emitting devices of different colors, A gap is provided. Thus, EL layer 120R, EL layer 120G, and EL layer 12 It is preferable that the 0Bs are arranged so that they do not touch each other. This ensures that adjacent 2 Current flows through the EL layer, effectively preventing unintended light emission. Therefore, it is possible to increase contrast and realize a display device with high display quality.

[0272] In Figure 14(C), the EL layer 120R is continuous in the Y direction. An example of 20R being formed in a strip shape is shown. By forming the EL layer 120R, etc., in a strip shape... This eliminates the need for space to separate these, and reduces the area of ​​the non-emitting region between light-emitting devices. Because it can be reduced in size, the aperture ratio can be increased. Figure 14(C) shows an example of light emission. The image shows a cross-section of device 110R, as well as light-emitting devices 110G and 110 The same shape can be applied to B. Note that the EL layer is light-emitting device in the Y direction. They may be separated into individual units.

[0273] On the second electrode 102 are light-emitting devices 110R, 110G, and A protective layer 131 is provided to cover the vice 110B. The protective layer 131 is provided from above each It has a function to prevent impurities such as water from diffusing into the light-emitting device.

[0274] The protective layer 131 may be, for example, a single-layer structure or a multi-layer structure including at least an inorganic insulating film. This can be done. Examples of inorganic insulating films include silicon oxide films and silicon oxide nitride films. Film, silicon nitride film, silicon nitride film, aluminum oxide film, aluminum oxide nitride Examples include films, oxide films such as hafnium oxide films, or nitride films. Alternatively, protective layer 13 1. Semiconductor materials such as indium gallium oxide and indium gallium zinc oxide You may use it.

[0275] Furthermore, a laminated film of an inorganic insulating film and an organic insulating film can also be used as the protective layer 131. For example, it is preferable to have a configuration in which an organic insulating film is sandwiched between a pair of inorganic insulating films. Furthermore, it is preferable that the organic insulating film functions as a planarizing film. This allows the organic insulating film to function on top of Because the surface can be made flat, the coverage of the inorganic insulating film on it is improved, and the barrier This can improve performance. Also, since the upper surface of the protective layer 131 becomes flat, the protective layer 131 Structures above (e.g., color filters, touch sensor electrodes, or lens arrays) When providing this feature, it is preferable because it can reduce the influence of uneven shapes caused by the structure below.

[0276] Figure 14(A) also shows the connecting electrode 101C that is electrically connected to the second electrode 102. The connecting electrode 101C supplies a potential (e.g., ANO) to the second electrode 102. A cathode potential (or cathode potential) is applied. The connecting electrode 101C is connected to the light-emitting device 110 It is located outside the display area where R and other elements are arranged. Also, Figure 14(A) shows the second electrode 102 This is indicated by a dashed line.

[0277] The connecting electrode 101C can be provided along the outer periphery of the display area. For example, the display area It may be provided along one side of the outer perimeter, or it may be provided across two or more sides of the outer perimeter of the display area. It may be kicked. That is, if the top shape of the display area is rectangular, the connecting electrodes The top surface shape of 101C may be strip-shaped, L-shaped, U-shaped (angle bracket-shaped), or rectangular. It is possible.

[0278] Figure 14(D) is a schematic cross-sectional view corresponding to the dashed line C1-C2 in Figure 14(A). Figure 14(D) shows the connection part 1 where the connecting electrode 101C and the second electrode 102 are electrically connected. It shows 30. At the connection part 130, the second electrode 102 is in contact with the connecting electrode 101C. A protective layer 131 is provided to cover the second electrode 102. An insulating layer 124 is provided covering the end of 01C.

[0279] [Example of manufacturing method] The following describes an example of a method for manufacturing a display device according to one aspect of the present invention, with reference to the drawings. Here, we will explain using the light-emitting device 450 shown in the above configuration example as an example. Figure 15(A Figures 15(F) to 15(F) show schematic cross-sectional views of each step in the manufacturing method of the display device illustrated below. This is a diagram. Also, in Figure 15(A), etc., the right side shows a schematic cross-section of the connection part 130 and its vicinity. The diagram is shown for illustrative purposes.

[0280] Furthermore, thin films (insulating films, semiconductor films, conductive films, etc.) that make up the display device are produced by sputtering. Chemical vapor deposition (CVD) method, Vacuum deposition, pulsed laser deposition (PLD) ion) method, Atomic Layer Deposition (ALD) It can be formed using methods such as CVD. CVD methods include plasma chemical vapor deposition (PEC). These methods include VD (Plasma Enhanced CVD) or thermal CVD. One of the thermal CVD methods is metal-organic chemical vapor deposition (MOCVD). There is a method called NIC CVD.

[0281] Furthermore, thin films (insulating films, semiconductor films, conductive films, etc.) that make up the display device can be spin-coated, defrosted, and defrosted. Tap, spray coating, inkjet, dispensing, screen printing, offset printing Printing, doctor knife, slit coat, roll coat, curtain coat, knife coat, etc. It can be formed by the following method.

[0282] Furthermore, when processing the thin films that make up the display device, photolithography and other methods are used. This can be done. In addition, nanoimprint lithography, sandblasting, lift-off lithography, etc. Further thin films may be processed. Alternatively, a film deposition method using a shielding mask such as a metal mask may be used. Alternatively, island-shaped thin films may be formed directly.

[0283] There are two main methods of photolithography. One is to process the image... A resist mask is formed on a thin film, and the thin film is processed by etching or the like, and the resist This is a method for removing the mask. Another method is to deposit a photosensitive thin film and then expose it to light. This method involves developing the film and then processing it into a desired shape.

[0284] In photolithography, the light used for exposure is, for example, the i-line (wavelength 365 nm). Using g-line (wavelength 436 nm), h-line (wavelength 405 nm), or a mixture thereof This can be done by using ultraviolet light, KrF laser light, or ArF laser light, etc. It is also possible to perform exposure using immersion lithography. Furthermore, the light used for exposure and Extreme ultraviolet (EUV) light, X-rays, etc. It may be used. Alternatively, an electron beam can be used instead of the light used for exposure. (Extreme) Using ultraviolet light, X-rays, or electron beams is preferable because it allows for extremely fine processing. Furthermore, when exposure is performed by scanning a beam such as an electron beam, photomass The "ku" is unnecessary.

[0285] Thin film etching methods include dry etching, wet etching, and sandblasting. Laws and other regulations can be used.

[0286] [Preparation of circuit board 100] The substrate 100 is a substrate that has at least enough heat resistance to withstand subsequent heat treatment. It is possible. When an insulating substrate is used as substrate 100, a glass substrate or quartz substrate can be used. Substrates, sapphire substrates, ceramic substrates, organic resin substrates, etc., can be used. Single-crystal semiconductor substrates, polycrystalline semiconductor substrates, silicon, silicon carbide, etc. It is possible to use semiconductor substrates such as compound semiconductor substrates like congermanium, or SOI substrates. Cut.

[0287] In particular, the substrate 100 is a semiconductor substrate or an insulating substrate on which transistors and other components are placed. It is preferable to use a substrate on which a semiconductor circuit including semiconductor elements is formed. Examples include pixel circuits, gate line drive circuits (gate drivers), and source line drive circuits (sources). It is preferable that the components include drivers, etc. In addition to the above, arithmetic circuits and memory circuits are also included. It may also consist of such things.

[0288] [Formation of the first electrodes 101R, 101G, 101B and the connecting electrode 101C] Next, the first electrode 101R, the first electrode 101G, and the first electrode 101 are placed on the substrate 100. B and connecting electrode 101C are formed. First, a conductive film that will become the anode (pixel electrode) is deposited, A resist mask is formed using photolithography, and unwanted parts of the conductive film are etched away. Further removal. Then, by removing the resist mask, the first electrode 101R, the first Electrode 101G and the first electrode 101B can be formed.

[0289] When a conductive film that reflects visible light is used as each pixel electrode, in the visible light wavelength range Apply materials with the highest possible reflectivity (e.g., silver or aluminum) throughout the entire area. This is preferable. This not only improves the light extraction efficiency of the light-emitting device, but also allows for color reproduction. The visibility can be improved. A conductive film that is reflective to visible light is used as each pixel electrode. In that case, it becomes a so-called top-emission light-emitting device that extracts light in the opposite direction to the substrate. This is possible. When a light-transmitting conductive film is used as each pixel electrode, light is emitted in the direction of the substrate. It can be used as a so-called bottom-emission light-emitting device to extract [the material].

[0290] [Formation of insulating layer 124] Next, the ends of the first electrode 101R, the first electrode 101G, and the first electrode 101B are This is used to cover and form an insulating layer 124 (Figure 15(A)). The insulating layer 124 is an organic insulating film. Alternatively, an inorganic insulating film can be used. The insulating layer 124 will cover the step of the EL film that will be formed later. To improve coverage, it is preferable to tapered the edges. In particular, for organic insulating films. When using this method, if a photosensitive material is used, the shape of the edges can be controlled by the exposure and development conditions. It is preferable because it is easy to manage. However, if the insulating layer 124 is not provided, the distance between the light-emitting devices This makes it possible to bring the objects even closer together, resulting in a higher-resolution light-emitting device.

[0291] [Formation of EL film 120Rb] Next, the first electrode 101R, the first electrode 101G, the first electrode 101B, and the insulating layer An EL film 120Rb, which will later become the EL layer 120R, is deposited on 124.

[0292] The EL film 120Rb has an emissive layer containing at least an emissive material and a hole transport layer. Other functions include film capsules that function as electron injection layers, electron transport layers, charge generation layers, or hole injection layers. The structure may consist of one or more layers stacked together. The EL film 120Rb can be, for example, deposited by evaporation, spalling, etc. It can be formed by the taring method, the inkjet method, etc. However, it is not limited to these methods. Furthermore, the above-described film formation method can be used as appropriate.

[0293] As an example, the EL film 120Rb consists of a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer. It is preferable that the layers be stacked in this order to form a laminated film. In this case, the EL layer to be formed later As an example, a film having an electron injection layer 115 can be used. In this configuration, an electron transport layer is provided to cover the light-emitting layer, which is then used in subsequent photolithography processes. This can further suppress damage to the light-emitting layer, resulting in a more reliable light-emitting device. It can be manufactured.

[0294] It is preferable that the EL film 120Rb is formed so as not to be present on the connecting electrode 101C. For example, when forming the EL film 120Rb by deposition (or sputtering), To prevent the EL film 120Rb from forming on the secondary electrode 101C, a shielding mask is used during formation. Alternatively, it is preferable to remove it in a later etching process.

[0295] [Formation of sacrificial film 144a] Next, the EL film 120Rb is covered to form a sacrificial film 144a. It is provided in contact with the upper surface of the connecting electrode 101C.

[0296] The sacrificial film 144a provides resistance to etching of each EL film, such as the EL film 120Rb. A high film, i.e., a film with a high etching selectivity ratio, can be used. Also, a sacrificial film 1 44a is a film that has a high selectivity ratio for etching with protective films such as the protective film 146a described later. It is possible. Furthermore, the sacrificial film 144a is wet, causing less damage to each EL film. A film that can be removed by etching can be used.

[0297] Examples of sacrificial films 144a include metal films, alloy films, metal oxide films, semiconductor films, and inorganic insulating films. Inorganic films such as edge films can be used. Sacrificial film 144a can be produced by sputtering or vapor deposition. These can be formed by various film deposition methods such as CVD and ALD.

[0298] Examples of sacrificial films 144a include gold, silver, platinum, magnesium, nickel, and tungsten. Chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, t Metallic materials such as thorium, zirconium, and tantalum, or alloy materials containing such metallic materials Materials can be used. In particular, low-melting-point materials such as aluminum or silver can be used. preferable.

[0299] Furthermore, as the sacrificial film 144a, indium gallium zinc oxide (In-Ga-Zn acid) Metal oxides such as IGZO (also written as IGZO) can be used. Furthermore, IGZO Indium, indium zinc oxide (In-Zn oxide), indium tin oxide (In- Sn oxide, indium titanium oxide (In-Ti oxide), indium tin zinc oxide Indium titanium zinc oxide (In-Sn-Zn oxide), indium titanium zinc oxide (In-Ti-Zn oxide) ), and indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide) are used. This is possible. Alternatively, indium tin oxide containing silicon can also be used.

[0300] Note that the above gallium can be replaced with element M (where M is aluminum, silicon, boron, yt). Rium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium Umium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten This also applies when using one or more types of ions or magnesium selected from those sources. In particular, M is one or more selected from gallium, aluminum, or yttrium. It is preferable to use it as a seed.

[0301] Furthermore, the sacrificial film 144a can be aluminum oxide, hafnium oxide, silicon oxide, etc. Any inorganic insulating material can be used.

[0302] Furthermore, as a sacrificial film 144a, at least the film located on top of the EL film 120Rb Therefore, it is preferable to use a material that can be dissolved in a chemically stable solvent. In particular, water or Materials that dissolve in alcohol can be suitably used in the sacrificial film 144a. When forming film a, the material is dissolved in a solvent such as water or alcohol, and then wet-processed. It is preferable to perform a heat treatment to evaporate the solvent after coating using the film formation method. At that time, by performing heat treatment under a reduced pressure atmosphere, the solvent can be removed at a low temperature and in a short time. This is preferable because it can reduce thermal damage to the EL film 120Rb.

[0303] Wet film deposition methods that can be used to form the sacrificial film 144a include spin coating, Dip, spray coating, inkjet, dispensing, screen printing, offset Printing, Doctor Knife method, slit coating, roll coating, curtain coating, knife coating There are things like T, etc.

[0304] The sacrificial film 144a is polyvinyl alcohol (PVA), polyvinyl butyral, Polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble Organic materials such as cellulose or alcohol-soluble polyamide resin can be used. Cut.

[0305] [Formation of protective film 146a] Next, a protective film 146a is formed on the sacrificial film 144a (Figure 15(B)).

[0306] The protective film 146a is later used as a hard mask when etching the sacrificial film 144a. It is a film. Also, during the subsequent processing of the protective film 146a, the sacrificial film 144a is exposed. Therefore, the sacrificial film 144a and the protective film 146a are films that have a high etching selectivity ratio with respect to each other. Select a combination. Therefore, the etching conditions for the sacrificial film 144a and the protective film 146 Depending on the etching conditions of a, a film that can be used for the protective film 146a can be selected. can.

[0307] For example, a fluorine-containing gas (also called a fluorine-based gas) is used for etching the protective film 146a. When using dry etching with silicon, silicon nitride, silicon oxide, Contains tungsten, titanium, molybdenum, tantalum, tantalum nitride, molybdenum, and niobium. Using an alloy containing molybdenum and tungsten, or an alloy containing molybdenum and tungsten, for the protective film 146a. This can be done. Here, compared to dry etching using the above fluorine-based gas, etching As a film that allows for a high selectivity ratio (i.e., a slower etching rate), IGZ Examples include metal oxide films such as O and ITO, which can be used as the sacrificial film 144a. .

[0308] Furthermore, the protective film 146a is made from various materials, including the sacrificial film 144a. The etching conditions and the etching conditions of the protective film 146a can be selected accordingly. For example, it is also possible to select from among the films that can be used for the sacrificial film 144a described above.

[0309] Furthermore, for example, a nitride film can be used as the protective film 146a. Specifically, Silicon nitride, aluminum nitride, hafnium nitride, titanium nitride, tantalum nitride, titanium nitride Nitrides such as sten, gallium nitride, and germanium nitride can also be used.

[0310] Alternatively, an oxide film can be used as the protective film 146a. Typically, an oxide film can be used. Ricon, silicon oxide nitride, aluminum oxide, aluminum oxide nitride, hafnium oxide Alternatively, oxide films such as hafnium oxynitride or oxynitride films can be used.

[0311] Furthermore, as the protective film 146a, an organic film that can be used for EL film 120Rb, etc., is used. It is acceptable to use the same organic film used for EL film 120Rb and EL film 120Gb. It can be used for the protective film 146a. By using such an organic film, the EL film 120 This is preferable because it allows the same film deposition equipment to be used for Rb and other materials.

[0312] [Formation of resist mask 143a] Next, on the protective film 146a, a position overlapping with the first electrode 101R, and the connecting electrode A resist mask 143a is formed in the position overlapping with 101C (Figure 15(C)). .

[0313] The resist mask 143a is a positive-type resist material, or a negative-type resist material, etc. A resist material containing a photosensitive resin can be used.

[0314] Here, without a protective film 146a, a resist mask 143a is formed on the sacrificial film 144a. If this occurs, and if defects such as pinholes exist in the sacrificial film 144a, the solvent of the resist material will This may cause the EL film 120Rb to dissolve. Use protective film 146a. This prevents such problems from occurring.

[0315] Furthermore, if a film that is less prone to defects such as pinholes is used for the sacrificial film 144a, protection Even if the resist mask 143a is formed directly on the sacrificial film 144a without using film 146a, good.

[0316] [Etching of protective film 146a] Next, the portion of the protective film 146a that is not covered by the resist mask 143a is etched. Further removal is performed to form a strip-shaped protective layer 147a. At the same time, on the connecting electrode 101C A protective layer 147a is also formed.

[0317] When etching the protective film 146a, the sacrificial film 144a is not removed by the etching. Therefore, it is preferable to use etching conditions with a high selectivity. Ting can be done by wet etching or dry etching, but dry By using etching, the reduction in the pattern of the protective film 146a can be suppressed.

[0318] [Removal of resist mask 143a] Next, remove the resist mask 143a (Figure 15(D)).

[0319] The resist mask 143a is removed by wet etching or dry etching. This can be done. In particular, dry etching using oxygen gas as the etching gas (plasm It is preferable to remove the resist mask 143a by (also known as mashing).

[0320] At this time, the removal of the resist mask 143a occurs when the EL film 120Rb covers the sacrificial film 144a. Because the process is carried out in a broken state, the impact on the EL film 120Rb is suppressed. In particular, the EL film When 120Rb comes into contact with oxygen, it can adversely affect its electrical properties, so plasma up This is suitable for etching using oxygen gas, such as with SING.

[0321] [Etching of sacrificial film 144a] Next, the protective layer 147a is used as a mask to cover the protective layer 147a of the sacrificial film 144a. A portion that does not crack is removed by etching to form a strip-shaped sacrificial layer 145a (Figure 15(E At the same time, a sacrificial layer 145a is also formed on the connecting electrode 101C.

[0322] The sacrificial film 144a is etched by wet etching or dry etching. While it is possible to do so, using the dry etching method is preferable because it can suppress the reduction of the pattern. It seems so.

[0323] [Etching of EL film 120Rb and protective layer 147a] Next, the protective layer 147a is etched, and at the same time, the EL that is not covered by the sacrificial layer 145a is etched. A portion of the film 120Rb is removed by etching to form a strip-shaped EL layer 120R (Figure 1). 5(F)). At the same time, the protective layer 147a on the connecting electrode 101C is also removed.

[0324] By etching the EL film 120Rb and the protective layer 147a using the same process, This is preferable because it simplifies the process and reduces the manufacturing cost of the display device.

[0325] In particular, etching of the EL film 120Rb requires an etching gas that does not contain oxygen as its main component. It is preferable to use dry etching. This prevents alteration of the EL film 120Rb. This allows for suppression and the realization of highly reliable display devices. Etching gas that does not contain oxygen as its main component and For example, CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, H2 Alternatively, noble gases such as helium can be used. Furthermore, the above gas and an oxygen-free diluent gas can be used. A mixed gas can be used as an etching gas.

[0326] Furthermore, etching of the EL film 120Rb and etching of the protective layer 147a were performed separately. This is also possible. In this case, the EL film 120Rb may be etched first, or the protective layer 147a You can etch it first.

[0327] At this point, the EL layer 120R and the connecting electrode 101C are covered by the sacrificial layer 145a. This results in the following state.

[0328] [Formation of EL film 120Gb] Next, on the sacrificial layer 145a, insulating layer 124, first electrode 101G, and first electrode 101B Next, an EL film 120Gb, which will later become the EL layer 120G, is deposited. At this time, the above EL film 12 Similar to 0Rb, it is preferable not to provide the EL film 120Gb on the connecting electrode 101C.

[0329] The method for forming the EL film 120Gb can be described by referring to the description of the EL film 120Rb above.

[0330] [Formation of sacrificial film 144b] Next, a sacrificial film 144b is formed on the EL film 120Gb. It can be formed in the same manner as the sacrificial film 144a. In particular, the sacrificial film 144b is a sacrificial film It is preferable to use the same material as 144a.

[0331] At the same time, a sacrificial film 144 covers the sacrificial layer 145a on the connecting electrode 101C. a is formed.

[0332] [Formation of protective film 146b] Next, a protective film 146b is formed on the sacrificial film 144b. It can be formed in the same manner as protective film 146a. In particular, protective film 146b is the same protective film as above. It is preferable to use the same material as film 146a.

[0333] [Formation of resist mask 143b] Next, on the protective film 146b, the region overlapping with the first electrode 101G, and the connecting electrode A resist mask 143b is formed in the region overlapping with 101C (Figure 16(A)).

[0334] The resist mask 143b is formed in the same manner as the resist mask 143a. It is possible.

[0335] [Etching of protective film 146b] Next, the portion of the protective film 146b that is not covered by the resist mask 143b is etched. Further removal is performed to form a strip-shaped protective layer 147b (Figure 16(B)). At the same time, the connection A protective layer 147b is also formed on electrode 101C.

[0336] For etching of protective film 146b, refer to the description of protective film 146a above. can.

[0337] [Removal of resist mask 143b] Next, remove the resist mask 143b. The removal of resist mask 143b is as described above. The description in resist mask 143a can be used as a reference.

[0338] [Etching of sacrificial film 144b] Next, the protective layer 147b is used as a mask to cover the protective layer 147b of the sacrificial film 144b. A portion that does not crack is removed by etching to form a strip-shaped sacrificial layer 145b. Sometimes, a sacrificial layer 145b is also formed on the connecting electrode 101C. Sacrificial layer 145a and sacrificial layer 145b are stacked on top of each other.

[0339] The etching of the sacrificial film 144b can be performed by referring to the description of the sacrificial film 144a above.

[0340] [Etching of EL film 120Gb and protective layer 147b] Next, the protective layer 147b is etched, and at the same time, the EL that is not covered by the sacrificial layer 145b is etched. A portion of the 120Gb film is removed by etching to form a strip-shaped EL layer 120G (Figure 1). 6(C)). At the same time, the protective layer 147b on the connecting electrode 101C is also removed.

[0341] Etching of the EL film 120Gb and protective layer 147b is performed on the EL film 120Rb and protective layer 147b. The description in layer 147a can be used as a reference.

[0342] At this time, the EL layer 120R is protected by the sacrificial layer 145a, so the EL film 120G This prevents damage during the etching process of step b.

[0343] In this way, the strip-shaped EL layer 120R and the strip-shaped EL layer 120G are positioned with high positional accuracy. They can be made in different ways.

[0344] [Formation of EL layer 120B] By performing the above steps on the EL film 120Bb (not shown), an island-shaped EL layer 1 A layer 20B and an island-like sacrificial layer 145c can be formed (Figure 16(D)).

[0345] That is, after the formation of the EL layer 120G, the EL film 120Bb, sacrificial film 144c, and protective film 14 6c and the resist mask 143c (neither of which are shown in the figure) are formed in order. Subsequently, After etching the protective film 146c to form a protective layer 147c (not shown), a resist is applied. Remove the mask 143c. Next, etch the sacrificial film 144c to create the sacrificial layer 145c. Formed. Then, the protective layer 147c and the EL film 120Bb are etched to form a strip-shaped EL. Forms layer 120B.

[0346] Furthermore, after the formation of the EL layer 120B, a sacrificial layer 145c is also formed on the connecting electrode 101C at the same time. This is done. On the connecting electrode 101C, there are sacrificial layers 145a, 145b, and 14 5c is stacked.

[0347] [Removal of the sacrificial layer] Next, sacrificial layers 145a, 145b, and 145c are removed, and the EL layer 12 The upper surfaces of 0R, EL layer 120G, and EL layer 120B are exposed (Figure 16(E)). At the same time, the upper surface of the connecting electrode 101C is also exposed.

[0348] Sacrificial layers 145a, 145b, and 145c are wet-etched or It can be removed by dry etching. At this time, EL layer 120R, EL layer 12 It is preferable to use a method that causes as little damage as possible to the 0G and EL layer 120B. In particular, it is preferable to use a wet etching method. For example, tetramethyl hydroxide Aqueous solution of hummonium (TMAH), dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or this It is preferable to use wet etching with a mixture of these liquids.

[0349] Alternatively, sacrificial layers 145a, 145b, and 145c may be filled with water or alcohol. It is preferable to remove it by dissolving it in a solvent such as ru. Here, sacrificial layer 145a, sacrificial Ethyl alcohol is an alcohol that can dissolve the sacrificial layer 145b and the sacrificial layer 145c. Various types of alcohols, such as methyl alcohol, isopropyl alcohol (IPA), or glycerin. Alcohol can be used.

[0350] After removing sacrificial layers 145a, 145b, and 145c, the EL layer 120 Water contained within R, EL layer 120G, and EL layer 120B, and water adsorbed on the surface To remove it, a drying treatment is preferable. For example, in an inert gas atmosphere or a reduced pressure atmosphere. It is preferable to perform the heat treatment under ambient air conditions. The heat treatment should be performed at a substrate temperature of 50°C or higher. 200°C or lower, preferably 60°C to 150°C, more preferably 70°C to 120°C The process can be carried out at the following temperatures. Drying can be performed at even lower temperatures by using a reduced pressure atmosphere. Therefore, it is preferable.

[0351] In this way, EL layer 120R, EL layer 120G, and EL layer 120B are created separately. It is possible.

[0352] [Formation of electron injection layer 115] Next, electron injection layer 1 covers EL layer 120R, EL layer 120G, and EL layer 120B. Form film 15.

[0353] The electron injection layer 115 can be formed using the same method as the EL film 120Rb. When the electron injection layer 115 is deposited by the deposition method, the electron injection layer 115 is connected to the connecting electrode 101C It is preferable to use a shielding mask to form the film so that it does not form on top of the existing film.

[0354] [Formation of the second electrode 102] Next, the electron injection layer 115 and the connecting electrode 101C are covered to form the second electrode 102. (Figure 16(F)).

[0355] The second electrode 102 is formed by a film deposition method such as vapor deposition or sputtering. This can be done. Alternatively, a film formed by vapor deposition and a film formed by sputtering can be laminated together. This may also be done. In this case, the second electrode shall be placed so as to encompass the region in which the electron injection layer 115 is formed. It is preferable to form 102. That is, the end of the electron injection layer 115 is the second electrode 1 It can be configured to superimpose with 02. The second electrode 102 is formed using a shielding mask. It is preferable to do so.

[0356] The second electrode 102 is electrically connected to the connecting electrode 101C outside the display area.

[0357] [Formation of a protective layer] Next, a protective layer is formed on the second electrode 102. The inorganic insulating film used for the protective layer is then deposited. For this, it is preferable to use the sputtering method, PECVD method, or ALD method. The ALD method is preferable because it offers excellent step coverage and is less prone to defects such as pinholes. Furthermore, when using the inkjet method to deposit organic insulating films, a uniform film can be formed in the desired area. This is preferable because it can be achieved.

[0358] Based on the above, a light-emitting device according to one aspect of the present invention can be manufactured.

[0359] Furthermore, in the above, the second electrode 102 and the electron injection layer 115 are given different top surface shapes. The example shown illustrates the formation of sea urchins, but these can also be formed in the same region.

[0360] In this specification, etc., metal mask or FMM (Fine Metal Mask, High Devices fabricated using a fine metal mask are called MM (metal mask) structure devices. It may be referred to as "S". Also, in this specification, etc., metal mask or FMM is used. Devices manufactured without the need for a metal mask are called MML (Metal Maskless) devices. There are cases where this occurs.

[0361] (Embodiment 4) In this embodiment, an example of using the light-emitting device described in Embodiment 1 as an illumination device is shown in Figure I will explain this while referring to Figure 6. Figure 6(B) is a top view of the lighting device, and Figure 6(A) is a top view of Figure 6(B). This is a cross-sectional view along the line segment ef shown.

[0362] In this embodiment, the lighting device has an anode 4 on a translucent substrate 400 which is a support. 01 is formed. The anode 401 corresponds to the first electrode 101 in Embodiment 1. When light is extracted from the anode 401 side, the anode 401 is formed from a light-transmitting material. ru.

[0363] A pad 412 for supplying voltage to the cathode 404 is formed on the substrate 400.

[0364] An EL layer 403 is formed on the anode 401. The EL layer 403 is in Embodiment 1 This corresponds to the configuration of EL layer 103, etc. Please refer to the relevant description for details on these configurations. sea ​​bream.

[0365] The cathode 404 is formed by covering the EL layer 403. The cathode 404 is the second in Embodiment 1. This corresponds to electrode 102. When light is extracted from the anode 401 side, cathode 404 has high reflectivity. It is formed from a material. The cathode 404 is connected to the pad 412, and the voltage is It will be supplied.

[0366] The above describes the light-emitting device having an anode 401, an EL layer 403, and a cathode 404 in this embodiment. The lighting device shown is equipped with the light-emitting device. The light-emitting device is a light-emitting device with high luminous efficiency. Therefore, the lighting device in this embodiment can be a lighting device with low power consumption.

[0367] The substrate 400 on which the light-emitting device having the above configuration is formed and the sealing substrate 407 are sealed The lighting device is completed by fixing and sealing it using materials 405 and 406. Either 405 or 406 is acceptable. Also, the inner sealing material 406 (Figure 6 (B) (Not shown) A desiccant can also be mixed in, which allows it to absorb moisture. This leads to improved reliability.

[0368] Furthermore, the pad 412 and a portion of the anode 401 are extended outside the sealing materials 405 and 406. This allows it to be used as an external input terminal. Furthermore, a converter or similar device can be mounted on top of it. An IC chip 420 or similar may be provided.

[0369] As described above, the lighting device described in this embodiment has an EL element and the light-emitting device described in Embodiment 1. This technology allows for a lighting device with low power consumption.

[0370] Furthermore, this embodiment can be freely combined with other embodiments.

[0371] (Embodiment 5) In this embodiment, an example of an electronic device that includes the light-emitting device described in Embodiment 1 as a part thereof is provided. This will be explained. The light-emitting device described in Embodiment 1 has good luminous efficiency and low power consumption. It is a small light-emitting device. As a result, the electronic device described in this embodiment has low power consumption. It is possible to create an electronic device that has a small light-emitting part.

[0372] Examples of electronic devices to which the above-mentioned light-emitting device is applied include television equipment (televisions, and (Also called a television receiver), monitors for computers, digital cameras, digital cameras Digital video cameras, digital photo frames, mobile phones (both mobile phones and mobile phone devices) (Examples include) portable game consoles, personal digital assistants, audio playback devices, and large game machines such as pachinko machines. These are some examples. Specific examples of these electronic devices are shown below.

[0373] Figure 7(A) shows an example of a television system. The television system is housed in a 710 enclosure. The display unit 7103 is incorporated into part 1. Also, the housing is connected by the stand 7105. This shows the configuration supporting 7101. The display unit 7103 can display video. The display unit 7103 is capable of arranging the light-emitting devices described in Embodiment 1 in a matrix. It is composed of the following.

[0374] The television equipment is operated using the control switches on the housing 7101 or a separate remote control. This can be done using the control unit 7110. The remote control unit 7110 has an operation key 71 09 allows you to operate the channel or volume, and the information is displayed on the display unit 7103. The video can be controlled. Furthermore, the remote control unit 7110 can be controlled by the remote control unit. A display unit 7107 may be provided to display the information output from 7110. The display unit 7107 also has the light-emitting devices described in Embodiment 1 arranged in a matrix. It can be used.

[0375] The television system shall consist of a receiver or modem, etc. It can receive regular television broadcasts, and also via a modem, either wired or wireless. By connecting to a communication network, communication can be unidirectional (sender to receiver) or bidirectional (sender to receiver). It is also possible to communicate information between believers and recipients, or between recipients themselves.

[0376] Figure 7(B1) is a computer, consisting of the main unit 7201, the casing 7202, the display unit 7203, and a key - Includes board 7204, external connection port 7205, pointing device 7206, etc. Furthermore, this computer arranges the light-emitting devices described in Embodiment 1 in a matrix. It is manufactured by using it in the display unit 7203. The computer in Figure 7(B1) is It may also be in a form like 7(B2). The computer in Figure 7(B2) has a keyboard 7 204. A display unit 7210 is provided instead of the pointing device 7206. The display unit 7210 is a touch panel, and the input table displayed on the display unit 7210 Input can be performed by operating the display with a finger or a dedicated pen. The 7210 can display not only input but also other images. Part 7203 may also be a touch panel. The two screens are connected by a hinge. Therefore, it also prevents problems such as scratching or damaging the screen during storage or transport. It can be stopped.

[0377] Figure 7(C) shows an example of a mobile terminal. The mobile phone is incorporated into the housing 7401. In addition to the display unit 7402, there are operation buttons 7403, an external connection port 7404, and a speaker 740 5. It is equipped with a microphone 7406, etc. The mobile phone is the light-emitting device described in Embodiment 1. It has a display unit 7402 made by arranging devices in a matrix.

[0378] The mobile terminal shown in Figure 7(C) allows users to input information by touching the display unit 7402 with their fingers or other objects. It can also be configured to allow for making phone calls or composing emails. Operations such as this can be performed by touching the display unit 7402 with a finger or the like.

[0379] The display unit 7402 has three main modes. The first is a display that primarily displays images. The first mode is display mode, the second is input mode which is primarily for inputting information such as characters. The third is display mode. This is a display + input mode, which is a combination of two modes: display mode and input mode.

[0380] For example, when making a phone call or composing an email, the display unit 7402 is used for text input. In this case, the primary text input mode should be used, and you should perform the input operation for the characters displayed on the screen. It is preferable to display a keyboard or number buttons on most of the screen of the display unit 7402. It seems so.

[0381] Furthermore, the mobile device has sensors inside that detect tilt, such as a gyroscope and an accelerometer. By installing the device, the orientation of the mobile terminal (portrait or landscape) is determined, and the screen display of the display unit 7402 is displayed accordingly. The display can be set to switch automatically.

[0382] Furthermore, screen modes can be switched by touching the display unit 7402 or by operating the housing 7401. This is done by operating button 7403. Also, the type of image displayed on display unit 7402 Therefore, it is also possible to switch between them. For example, the image signal displayed on the display unit is a video signal. Switch to display mode if it's data, or to input mode if it's text data.

[0383] Furthermore, in input mode, the signal detected by the optical sensor of the display unit 7402 is detected and displayed If there is no touch input on unit 7402 for a certain period of time, the screen mode will be changed to input mode. You may also control the system to switch from this mode to display mode.

[0384] The display unit 7402 can also function as an image sensor. For example, the display unit 74 By touching device 02 with the palm or finger, the user can authenticate their identity by capturing images of their palm print, fingerprints, etc. Furthermore, the display unit may have a backlight that emits near-infrared light or a sensing device that emits near-infrared light. Using a suitable light source, it is also possible to image finger veins, palmar veins, and other veins.

[0385] The configuration shown in this embodiment is achieved by appropriately combining the configurations shown in Embodiments 1 to 4. They can be used together.

[0386] As described above, the light-emitting device equipped with the light-emitting device described in Embodiment 1 or Embodiment 2 is suitable for Its range of applications is extremely wide, and this light-emitting device can be applied to electronic equipment in all fields. By using the light-emitting device described in Embodiment 1 or Embodiment 2, power consumption You can obtain small electronic devices.

[0387] Figure 8(A) is a schematic diagram showing an example of a cleaning robot.

[0388] The cleaning robot 5100 has a display 5101 located on the top and multiple displays located on the sides. It has several cameras 5102, brushes 5103, and operation buttons 5104. However, the underside of the 5100 cleaning robot is equipped with wheels, a suction port, etc. The 5100 robot also includes an infrared sensor, ultrasonic sensor, acceleration sensor, and piezo sensor. It is equipped with various sensors such as optical sensors and gyro sensors. Also, the cleaning robot 5 Unit 100 is equipped with wireless communication means.

[0389] The cleaning robot 5100 moves autonomously, detects the dirt 5120, and uses the suction port located on its underside to... It can then vacuum up the dust.

[0390] Furthermore, the cleaning robot 5100 analyzes images captured by the camera 5102, and detects walls, furniture, or It can determine the presence or absence of obstacles such as steps. Furthermore, image analysis can detect wiring and other obstacles. If an object that may become entangled in brush 5103 is detected, the rotation of brush 5103 will be stopped. can.

[0391] The display 5101 shows the battery level or the amount of dust collected. This is possible. The path taken by the cleaning robot 5100 is displayed on the display 5101. Alternatively, the display 5101 may be a touch panel, and the operation buttons 5104 may be a touch panel. It may also be provided in the spray 5101.

[0392] The cleaning robot 5100 can communicate with portable electronic devices 5140 such as smartphones. Yes, it is possible. Images captured by camera 5102 can be displayed on the portable electronic device 5140. Therefore, the owner of the 5100 cleaning robot can know what's happening in the room even when they're away from home. It is possible to display the information on the display 5101 on portable electronic devices such as smartphones. You can also check it there.

[0393] A light-emitting device according to one aspect of the present invention can be used in a display 5101.

[0394] The robot 2100 shown in Figure 8(B) consists of a computing unit 2110, an illuminance sensor 2101, and a microphone. Lophone 2102, upper camera 2103, speaker 2104, display 2105, bottom It is equipped with a camera 2106, an obstacle sensor 2107, and a moving mechanism 2108.

[0395] Microphone 2102 has the function of detecting the user's voice and ambient sounds, etc. Speaker 2104 has the function of emitting sound. Robot 2100 has a microphone Using the 2102 and speaker 2104, communication with the user is possible. It is possible.

[0396] The display 2105 has the function of displaying various information. The robot 2100 is The user can display the desired information on the display 2105. The 2105 may have a touch panel. Also, the display 2105 is removable. It can be any information terminal capable of charging, and by installing it in a fixed position on the robot 2100, And it enables the transfer of data.

[0397] The upper camera 2103 and lower camera 2106 are used to image the area around the robot 2100. It has the ability to detect obstacles. Furthermore, the obstacle sensor 2107 uses the moving mechanism 2108 to detect robot 210 Robot 21 can detect the presence or absence of obstacles in the direction of travel as it moves forward. 00 uses the upper camera 2103, the lower camera 2106 and the obstacle sensor 2107 The light-emitting device according to one aspect of the present invention can recognize its surroundings and move safely. It can be used in display 2105.

[0398] Figure 8(C) shows an example of a goggle-type display. For example, a housing 5000, a first display unit 5001, a speaker 5003, an LED lamp 50 04 (including power switch or operation switch), connection terminal 5006, sensor 5007 ( 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 i, or including a function to measure infrared radiation), microphone 5008, second display unit 5 It includes parts 002, a support part 5012, an earphone 5013, etc.

[0399] A light-emitting device according to one aspect of the present invention is used for a first display unit 5001 and a second display unit 5002. It is possible.

[0400] Figure 9 shows an example in which the light-emitting device described in Embodiment 1 is used in a desk lamp, which is a lighting device. The desk lamp shown in Figure 9 has a housing 2001 and a light source 2002. As for the second example, the lighting device described in Embodiment 4 may be used.

[0401] Figure 10 shows the light-emitting device described in Embodiment 1 used as an indoor lighting device 3001. This is an example. The light-emitting device described in Embodiment 1 is a light-emitting device with high luminous efficiency. This allows for a lighting device with low power consumption. Also, the light-emitting device described in Embodiment 1 Because chairs can be made to cover a large area, they can be used as large-area lighting devices. The light-emitting device described in Embodiment 1 is thin and can therefore be used as a thinned lighting device. This becomes possible.

[0402] The light-emitting device described in Embodiment 1 is mounted on the windshield or dashboard of an automobile. It can also be installed. Figure 11 shows the light-emitting device described in Embodiment 1 in an automobile's refrigerant. One embodiment for use on a glass or dashboard is shown. Display area 5200 to display area 5 203 is a display area provided using the light-emitting device described in Embodiment 1.

[0403] Display area 5200 and display area 5201 are in an embodiment provided on the windshield of an automobile. A display device equipped with the light-emitting device described in 1. The light-emitting device described in Embodiment 1. This is achieved by fabricating the anode and cathode with translucent electrodes, allowing the other side to be seen through. It can be used as a display device in a so-called see-through state. Even when installed on a car's windshield, it should be installed without obstructing the driver's view. This is possible. Furthermore, if transistors or other components for driving are provided, organic semiconductor materials can be used. Translucent organic transistors or transistors using oxide semiconductors, etc. Using a Rangista would be a good idea.

[0404] The display area 5202 is equipped with the light-emitting device described in Embodiment 1, which is provided in the pillar portion. This is a display device. The display area 5202 displays images from an imaging device installed on the vehicle body. By extending it, the view obstructed by the pillar can be compensated for. Also, similarly, The display area 5203 provided on the shoeboard section allows the view obstructed by the vehicle body to be seen by the automobile. By displaying images from externally mounted imaging devices, blind spots are compensated for, and safety is enhanced. It can be done by projecting images that complement the parts that are not visible, making it more natural. Safety checks can be performed without any sense of unease.

[0405] Additionally, the display area 5203 shows navigation information, driving speed or engine RPM, and air conditioning. By displaying settings and other information, various types of information can be provided. The display can be customized to the user's preference. The displayed items or layout can be changed as needed to suit the user. Information can also be provided in display areas 5200 to 5202. Areas 5200 to 5203 can also be used as lighting devices.

[0406] Furthermore, Figures 12(A) and 12(B) show a foldable portable information terminal 5150. The foldable portable information terminal 5150 consists of a housing 5151, a display area 5152 and a foldable lid. It has a curved section 5153. Figure 12(A) shows the portable information terminal 5150 in its unfolded state. Figure 12(B) shows the portable information terminal in its folded state. The portable information terminal 5150 is large Despite having a large display area of ​​5152, it folds up compactly and is highly portable. .

[0407] The display area 5152 can be folded in half by the bending portion 5153. Bending portion 515 3 consists of an expandable member and multiple support members, and when folded, the expandable The member stretches, and the bent portion 5153 has a radius of curvature of 2 mm or more, preferably 3 mm or more. It folds up.

[0408] Note that the display area 5152 is a touch panel (input / output) equipped with a touch sensor (input device). It may also be a device. The light-emitting device according to one aspect of the present invention can be used in the display area 5152. Cut.

[0409] Figures 13(A) to 13(C) also show a foldable portable information terminal 9310. Figure 13(A) shows the portable information terminal 9310 in its unfolded state. Figure 13(B) shows the unfolded state. A portable information terminal 9310 in a state in between, either in a normal state or a folded state, and changing to the other state. Figure 13(C) shows the folded state of the personal digital assistant (PDA). The 9310 offers excellent portability when folded, and a seamless, wide design when unfolded. The display area provides excellent readability.

[0410] The display panel 9311 is supported by three housings 9315 connected by hinges 9313. The display panel 9311 is a touch panel equipped with a touch sensor (input device). It may also be an input / output device. In addition, the display panel 9311 is connected via the hinge 9313. By bending the two housings 9315, the mobile information terminal 9310 is unfolded. It can be reversibly transformed from a folded state. A light-emitting device according to one aspect of the present invention It can be used with the display panel 9311. [Examples]

[0411] In this embodiment, in a light-emitting device having at least three layers in the hole transport region, Light-emitting devices with varying combinations of high and low refractive indices in three layers (light-emitting device 1 to The light-emitting device 8) will be described below. The structural formulas of the organic compounds used in this example are shown below. .

[0412] [ka]

[0413] (Method for fabricating light-emitting device 1) First, silver (Ag) is sputtered onto a glass substrate as a reflective electrode. After forming a film with a thickness of nm, indium tin oxide (ITSO) containing silicon oxide is used as a transparent electrode. The first electrode 101 was formed by depositing a film with a thickness of 10 nm using the sputtering method. The electrode area is 4 mm². 2 The dimensions were set to (2mm x 2mm). The first electrode 101 was transparent. It is a light electrode and can be considered as the first electrode together with the reflective electrode mentioned above.

[0414] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface is washed with water, and 2 After firing at 0°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0415] Then, 10 -4 A substrate is introduced into a vacuum deposition apparatus where the internal pressure is reduced to approximately Pa, and then vacuum deposition is performed. After vacuum firing at 170°C for 30 minutes in the heating chamber of the apparatus, the substrate is left for approximately 30 minutes. It was allowed to cool.

[0416] Next, the first electrode 101 is formed such that the surface on which the first electrode 101 is formed faces downwards. The prepared substrate is fixed to a substrate holder provided inside the vacuum deposition apparatus, and on the first electrode 101, 4,4'-bis(dibenzothiophen-4-i) represented by the above structural formula (i) obtained by vapor deposition. (Lu)-4''-(9-phenyl-9H-carbazole-2-yl)triphenylamine( Abbreviation: PCBDBtBB-02) and an electron acceptor material containing fluorine with a molecular weight of 672 (O CHD-003) and the weight ratio is 1:0.1 (=PCBDBtBB-02:OCHD-0 A hole injection layer 111 was formed by co-depositing 10 nm of material so that it would be as shown in 03).

[0417] On the hole injection layer 111, a first layer is formed, represented by the above structural formula (viii) N-(1,1 '-biphenyl-2-yl)-N-(3,3'',5',5''-tetra-t-butyl- 1,1':3',1''-terphenyl-5-yl)-9,9-dimethyl-9H-fluor Len-2-amine (abbreviation: mmtBumTPoFBi-02) is used as the second layer at a thickness of 35 nm. PCBDBtBB-02 is 40nm, and mmtBumTPoFBi-02 is used as the third layer. A 35nm layer was deposited to form a hole transport layer 112.

[0418] Next, PCBDBtBB-02 is deposited onto the hole transport layer 112 to a thickness of 10 nm. An electron block layer was formed.

[0419] Subsequently, the 2-(10-phenyl-9-anthracenyl)- represented by the above structural formula (ii) Benzo[b]naphtho[2,3-d]furan (abbreviation: Bnf(II)PhA) and the above structure 3,10-bis[N-(9-phenyl-9H-carbazole-2], represented by formula (iii) -yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (Abbreviation: 3,10PCA2Nbf(IV)-02) and by weight ratio 1:0.015 (=B nf(II)PhA:3,10PCA2Nbf(IV)-02) with 25nm A light-emitting layer 113 was formed by vapor deposition.

[0420] Subsequently, the structure represented by the above structural formula (iv) is 2-[3'-(9,9-dimethyl-9H-full [Olen-2-yl)-1,1'-biphenyl-3-yl]-4,6-diphenyl-1,3 ,5-triazine (abbreviated as mFBPTzn) is deposited to a thickness of 10 nm to form a hole block. After forming the layer, the 2-[3-(2,6-dimethyl-3-ply, represented by the above structural formula (v)) Lidinyl)-5-(9-phenantrenyl)phenyl]-4,6-diphenyl-1,3, 5-triazine (abbreviation: mPn-mDMePyPTzn) and the structure represented by the above structural formula (vi) 8-hydroxyquinolinatolithium (abbreviation: Liq) and are mixed in a weight ratio of 1:1 (=m A 20nm co-deposited electron transport layer 11 is formed using Pn-mDMePyPTzn:Liq. Formed 4.

[0421] After the electron transport layer 114 is formed, lithium fluoride (LiF) is deposited to a thickness of 1 nm. A sub-injection layer 115 is formed, and finally, silver (Ag) and magnesium (Mg) are mixed in a volume ratio of 1:0 1. A second electrode 102 is formed by co-depositing to a film thickness of 15 nm, and the light-emitting device Chair 1 was manufactured. It is a semi-transparent / semi-reflective material that possesses both the function of reflecting and transmitting light. The emission electrode is a top emitter that extracts light from the second electrode 102. It is a cushion-type element. Furthermore, the second electrode 102 is represented by the above structural formula (vii). 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (Abbreviation: DBT3P-II) is deposited at a 70nm layer to improve extraction efficiency.

[0422] (Method for fabricating comparative light-emitting device 1) Comparative light-emitting device 1 has a first layer and a third layer in the hole transport layer of light-emitting device 1 on a PCB. Except for changing to DBtBB-02 and setting the film thickness to 30nm for each, it is the same as light-emitting device 1. It was made in [year].

[0423] (Method for fabricating comparative light-emitting device 2) Comparative light-emitting device 2 has a second layer in the hole transport layer of light-emitting device 1, which is made of mmtBum. The fabrication process was the same as for light-emitting device 1, except that TPoFBi-02 was used and its film thickness was set to 60 nm. did.

[0424] The element structures of light-emitting device 1, comparative light-emitting device 1, and comparative light-emitting device 2 are shown in the table below. I've put it all together.

[0425] [Table 1]

[0426] [Table 2]

[0427] Furthermore, the paraphotonic refractive index of PCBDBtBB-02 and mmtBumTPoFBi-02 was measured. The results are shown in Figure 17. The measurement was performed using a spectroscopic ellipsometer (J.A. Woolam Japan). The measurement was performed using a (M-2000U) manufactured by [company name]. For the measurement sample, each layer of material was applied to a quartz substrate. A film with a thickness of approximately 50 nm was used, deposited by the air deposition method.

[0428] From the diagram, PCBDBtBB-02 and mmtBumTPoFBi-02 are from 450nm. Within the 650nm range, it was found that the difference between the two values ​​is between 0.2 and less than 0.5. Light.

[0429] Furthermore, PCBDBtBB- calculated from the results of cyclic voltammetry (CV) measurements The HOMO levels of 02 and mmtBumTPoFBi-02 are N,N-dimethylform The values ​​were -5.51 eV and -5.43 eV, respectively, when amide (DMF) was the solvent. Therefore, the HOMO of PCBDBtBB-02 and mmtBumTPoFBi-02 The difference in energy levels is less than 0.1 eV. The measurement device used for CV measurement is an electrochemical analyzer. Using Izer (manufactured by BAS Corporation, model number: ALS Model 600A or 600C) First, the solution obtained by dissolving the material to be measured in a solvent was measured.

[0430] The above-mentioned light-emitting device and comparative light-emitting device were placed in a glove box under a nitrogen atmosphere. The process of sealing the light-emitting device with a glass substrate to prevent it from being exposed to the atmosphere (UV curable Apply the sealing material around the element, and use UV light only on the sealing material, ensuring that the light-emitting device is not exposed to UV light. After irradiation and heat treatment (at atmospheric pressure at 80°C for 1 hour), these light-emitting devices Measurements were taken to determine the initial characteristics of the product.

[0431] The luminance-current density characteristics of light-emitting device 1, comparative light-emitting device 1, and comparative light-emitting device 2 are Figure 18 shows the luminance-voltage characteristics, Figure 19 shows the current efficiency-luminance characteristics, and Figure 20 shows the current density-voltage characteristics. The characteristics are shown in Figure 21, the blue index-luminance characteristics in Figure 22, and the emission spectrum in Figure 23. It is shown. Also, 1000 of light-emitting device 1, comparative light-emitting device 1 and comparative light-emitting device 2 cd / m 2Table 3 shows the main characteristics in the vicinity. Note that luminance, CIE chromaticity, and emission spectrum are not included. A spectroradiometer (Topcon SR-UL1R) was used to measure the ketol content, and the measurements were taken at room temperature. .

[0432] The Blue Index (BI) is calculated by dividing the current efficiency (cd / A) by the chromaticity y. The value (cd / A / y) is one of the indicators that represent the emission characteristics of blue light emission. Blue light emission is The smaller the chromaticity y, the higher the color purity of the emitted light tends to be. High color purity blue light is associated with high luminance. Even with small component sizes, it is possible to express a wide range of blue colors, resulting in high-purity blue emission. By using this technology, the required brightness for displaying blue is reduced, resulting in a reduction in power consumption. Therefore, BI, which takes into account chromaticity y, one of the indicators of blue purity, is effective for blue emission. It is preferably used as a means of representing a rate, and the higher the BI of a light-emitting device, the more likely it is to be used in a display. It can be said that it has good efficiency as a blue light-emitting device.

[0433] [Table 3]

[0434] From Figures 18 to 23 and Table 3, the light-emitting device 1, which is a light-emitting device according to one aspect of the present invention, is Compared to other light-emitting devices, it has good current efficiency and blue index (BI). It was identified as a chair. In particular, the BI was very high, over 200 (cd / A / y), and it emitted light. Device 1 can be said to be a particularly good light-emitting device for BI. Therefore, one of the present inventions The embodiment is particularly suitable for light-emitting devices used in displays. [Examples]

[0435] In this embodiment, a light-emitting device 10 is a light-emitting device according to one aspect of the present invention, and a comparative light-emitting device The comparative light-emitting device 10, which is a chair, will be described. The structure of the organic compound used in this embodiment. The formula is shown below.

[0436] [ka]

[0437] (Method for fabricating the light-emitting device 10) First, silver (Ag) is sputtered onto a glass substrate as a reflective electrode. After forming a film with a thickness of nm, indium tin oxide (ITSO) containing silicon oxide is used as a transparent electrode. The first electrode 101 was formed by depositing a film with a thickness of 10 nm using the sputtering method. The electrode area is 4 mm². 2 The dimensions were set to (2mm x 2mm). The first electrode 101 was transparent. It is a light electrode and can be considered as the first electrode together with the reflective electrode mentioned above.

[0438] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface is washed with water, and 2 After firing at 0°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0439] Then, 10 -4 A substrate is introduced into a vacuum deposition apparatus where the internal pressure is reduced to approximately Pa, and then vacuum deposition is performed. After vacuum firing at 170°C for 30 minutes in the heating chamber of the apparatus, the substrate is left for approximately 30 minutes. It was allowed to cool.

[0440] Next, the first electrode 101 is formed such that the surface on which the first electrode 101 is formed faces downwards. The prepared substrate is fixed to a substrate holder provided inside the vacuum deposition apparatus, and on the first electrode 101, N-3',5'-ditterybutyl-1, represented by the above structural formula (ix), obtained by vapor deposition. ,1'-biphenyl-4-yl-N-1,1'-biphenyl-2-yl-9,9-dimethyl Lu-9H-fluoren-2-amine (abbreviation: mmtBuBioFBi) has a molecular weight of 672. A fluorine-containing electron acceptor material (OCHD-003) and a fluorine-containing electron acceptor material in a weight ratio of 1:0.1 (=m A hole injection layer is formed by co-depositing 10 nm of material to create mtBuBioFBi:OCHD-003. 111 was formed.

[0441] On the hole injection layer 111, a 30 nm layer of mmtBuBioFBi is used as the first layer, and a second layer is used. The above structural formula (x) represents 4,4'-diphenyl-4''-(7;2'-binaphthin (Lu-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03) is 50 nm thick. A 40nm layer of mmtBuBioFBi was deposited as layer 3 to form a hole transport layer 112.

[0442] Next, on the hole transport layer 112, N,N-bis[4-(di] represented by the above structural formula (xi) is added. [Benzofran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfB) An electron blocking layer was formed by depositing B1TP to a thickness of 10 nm.

[0443] Subsequently, 9-(1-naphthyl)-10-[4-(2-naphthyl], represented by the above structural formula (xii), is formed. [Phthyl)phenyl]anthracene (abbreviation: αN-βNPAnth) and the above structural formula (ii i) 3,10-bis[N-(9-phenyl-9H-carbazole-2-yl) -N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3.10PCA2Nbf(IV)-02) and αN-βN in a weight ratio of 1:0.015 (=αN-βN Co-deposit 20 nm so that PAnth:3,10PCA2Nbf(IV)-02) A light-emitting layer 113 was formed.

[0444] Subsequently, the 6-(1,1'-biphenyl-3-yl)- represented by the above structural formula (xiv) 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrim Din (abbreviated as 6mBP-4Cz2PPm) is deposited to a thickness of 10 nm to block holes. After forming the layer, the 2-[3-(2,6-dimethyl-3-pyri) represented by the above structural formula (v) Dinyl)-5-(9-phenantrenyl)phenyl]-4,6-diphenyl-1,3,5 -Triaidine (abbreviation: mPn-mDMePyPTzn) and the structure represented by the above structural formula (vi) 8-hydroxyquinolinatolithium (abbreviation: Liq) and 8-hydroxyquinolinatolithium (mP) are mixed in a weight ratio of 1:1 (= mP A 20nm co-deposited electron transport layer 114 is formed using n-mDMePyPTzn:Liq. It formed.

[0445] After the electron transport layer 114 is formed, lithium fluoride (LiF) is deposited to a thickness of 1 nm. A sub-injection layer 115 is formed, and finally, silver (Ag) and magnesium (Mg) are mixed in a volume ratio of 1:0 1. A second electrode 102 is formed by co-depositing to a film thickness of 15 nm, and the light-emitting device Chair 10 was manufactured. It is a semi-transparent material that has both the function of reflecting light and the function of transmitting light. The reflective electrode, and the light-emitting device in this embodiment, extracts light from the second electrode 102. It is a mission-type element. Furthermore, the second electrode 102 is represented by the above structural formula (vii). 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) The extraction efficiency is improved by depositing (abbreviated as DBT3P-II) at a 70nm layer.

[0446] (Method for fabricating the comparative light-emitting device 10) The comparative light-emitting device 10 has a first layer thickness of 35 in the hole transport layer of the light-emitting device 10. The device is the same as light-emitting device 10, except that the second layer is formed with mmtBuBioFBi and the size is set to nm. It was made in [year].

[0447] The element structures of the light-emitting device 10 and the comparative light-emitting device 10 are summarized in the table below.

[0448] [Table 4]

[0449] Furthermore, the results of measuring the ordinary refractive index of BBA(βN2)B-03 and mmtBuBioFBi were obtained. This is shown in Figure 24. The measurement was performed using a spectroscopic ellipsometer (manufactured by J.A. Woolam Japan Co., Ltd.). The procedure was performed using the M-2000U. For the measurement sample, each layer of material was vacuum-deposited onto a quartz substrate. A film with a thickness of approximately 50 nm was used according to the method.

[0450] From the figure, BBA(βN2)B-03 and mmtBuBioFBi are 450nm to 650nm Within the nm range, it can be seen that the combinations have a difference of 0.2 or more and less than 0.5.

[0451] Furthermore, BBA(βN2)B was calculated from the results of cyclic voltammetry (CV) measurements. -03 and the HOMO levels of mmtBuBioFBi are N,N-dimethylformamide When (DMF) was the solvent, the values ​​were -5.47 eV and -5.42 eV, respectively. Therefore, the difference in HOMO levels between BBA(βN2)B-03 and mmtBuBioFBi is 0 It is less than 0.1 eV. The measurement device used for CV measurement is an electrochemical analyzer (B). Measurements will be taken using an ALS Model 600A or 600C (manufactured by A.S. Co., Ltd.). The solution, obtained by dissolving the material in a solvent, was measured.

[0452] The above-mentioned light-emitting device and comparative light-emitting device were placed in a glove box under a nitrogen atmosphere. The process of sealing the light-emitting device with a glass substrate to prevent it from being exposed to the atmosphere (UV curable Apply the sealing material around the element, and use UV light only on the sealing material, ensuring that the light-emitting device is not exposed to UV light. After irradiation and heat treatment (at atmospheric pressure at 80°C for 1 hour), these light-emitting devices Measurements were taken to determine the initial characteristics of the product.

[0453] Figure 25 shows the luminance-current density characteristics of the light-emitting device 10 and the comparative light-emitting device 10. Voltage characteristics are shown in Figure 26, current efficiency-luminance characteristics in Figure 27, and current density-voltage characteristics in Figure 28. The blue index-current density characteristics are shown in Figure 29, the emission spectrum in Figure 30, and the emission spectrum in Figure 31. The field-angle characteristics are shown. Also, the 1000 cd / m 2 Table 5 shows the main characteristics in the vicinity. Note that luminance, CIE chromaticity, and emission spectrum are also shown. A spectroradiometer (Topcon SR-UL1R) was used for the measurement, and the measurement was performed at room temperature. Field of view The angular characteristics are defined as the direction perpendicular to the light-emitting surface of the light-emitting device being 0°, and ranging from -80° to 80°. The emission spectrum was measured at 0° intervals to obtain the photon intensity ratio of the light-emitting element at each angle. A multi-channel spectrometer (Hamamatsu Photonics, PMA-12) was used for the measurements.

[0454] [Table 5]

[0455] As shown in Figures 25 to 31 and Table 5, the light-emitting device 10 according to one aspect of the present invention has current efficiency and blue It was found to be a good light-emitting device for the index (BI). In particular, BI is 200 (cd / A / y) is very high, and the light-emitting device 10 is a particularly good light-emitting device for BI. Therefore, one aspect of the present invention is a light-emitting device used in a display. It is particularly suitable for this purpose.

[0456] Furthermore, in the viewing angle characteristics shown in Figure 31, the light-emitting device 10 and the comparison light-emitting device 10 are almost identical. It can be seen that there is no difference. Therefore, according to one aspect of the present invention, the viewing angle characteristics can be changed. This can significantly improve the efficiency of light-emitting devices.

[0457] Furthermore, the current density is 50 mA / cm². 2 The graph shows the change in brightness with respect to operating time. As shown in 32, the light-emitting device 10 according to one aspect of the present invention is more reliable than the comparative light-emitting device 10. It was found to be a high-performance light-emitting device. [Examples]

[0458] This embodiment describes a light-emitting device 20, which is a light-emitting device according to one aspect of the present invention. The structural formulas of the organic compounds used in this example are shown below.

[0459] [ka]

[0460] (Method for fabricating the light-emitting device 20) First, silver (Ag) is sputtered onto a glass substrate as a reflective electrode. After forming a film with a thickness of nm, indium tin oxide (ITSO) containing silicon oxide is used as a transparent electrode. The first electrode 101 was formed by depositing a film with a thickness of 10 nm using the sputtering method. The electrode area is 4 mm².2 The dimensions were set to (2mm x 2mm). The first electrode 101 was transparent. It is a light electrode and can be considered as the first electrode together with the reflective electrode mentioned above.

[0461] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface is washed with water, and 2 After firing at 0°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0462] Then, 10 -4 A substrate is introduced into a vacuum deposition apparatus where the internal pressure is reduced to approximately Pa, and then vacuum deposition is performed. After vacuum firing at 170°C for 30 minutes in the heating chamber of the apparatus, the substrate is left for approximately 30 minutes. It was allowed to cool.

[0463] Next, the first electrode 101 is formed such that the surface on which the first electrode 101 is formed faces downwards. The prepared substrate is fixed to a substrate holder provided inside the vacuum deposition apparatus, and on the first electrode 101, N-3',5'-ditterybutyl-1, represented by the above structural formula (ix), obtained by vapor deposition. ,1'-biphenyl-4-yl-N-1,1'-biphenyl-2-yl-9,9-dimethyl Lu-9H-fluoren-2-amine (abbreviation: mmtBuBioFBi) has a molecular weight of 672. Fluorine-containing electron acceptor material (OCHD-003) and a weight ratio of 1:0.04 (= Hole injection by co-depositing 10 nm so that it becomes mmtBuBioFBi:OCHD-003) Layer 111 was formed.

[0464] On the hole injection layer 111, a 35nm layer of mmtBuBioFBi is used as the first layer, and a second layer is used. The above structural formula (x) represents 4,4'-diphenyl-4''-(7;2'-binaphthin (Lu-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03) is 50 nm thick. A 40nm layer of mmtBuBioFBi was deposited as layer 3 to form a hole transport layer 112.

[0465] Next, on the hole transport layer 112, N,N-bis[4-(di] represented by the above structural formula (xi) is added. [Benzofran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfB) An electron blocking layer was formed by depositing B1TP to a thickness of 10 nm.

[0466] Subsequently, 9-(1-naphthyl)-10-[4-(2-naphthyl], represented by the above structural formula (xii), is formed. [Phthyl)phenyl]anthracene (abbreviation: αN-βNPAnth) and the above structural formula (xi ii) 2,12-di(tert-butyl)-5,9-di(4-tert-butyl (ruphenyl)-N,N-diphenyl-5H,9H-[1,4]benzazabolino[2,3 ,4-kl]phenazavolin-7-amine (abbreviation: DPhA-tBu4DABNA) , by weight ratio 1:0.015 (=αN-βNPAnth:DPhA-tBu4DABNA) A light-emitting layer 113 was formed by co-depositing a 20nm layer in such a manner.

[0467] Subsequently, the 6-(1,1'-biphenyl-3-yl)- represented by the above structural formula (xiv) 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrim A din (abbreviated as 6mBP-4Cz2PPm) layer is deposited to a thickness of 5 nm to form a hole block layer. After forming the above structural formula (xv), 2,9-di(2-naphthyl)-4,7-di Phenyl-1,10-phenanthroline (abbreviation: NBPhen) is vapor-dried to a size of 5 nm. This formed an electron transport layer 114.

[0468] After the formation of the electron transport layer 114, bathophenanthroline represented by the above structural formula (xvi) (abbreviated) (Name: BPhen) and lithium fluoride (LiF) in a volume ratio of 1:3 (=BPhen:Li A 27nm co-deposited electron injection layer 115 was formed so that F), and finally, silver (Ag) and Co-deposit magnesium (Mg) with a volume ratio of 1:0.1 and a film thickness of 15 nm. A second electrode 102 was formed to create the light-emitting device 20. The light-emitting device in this embodiment is a semi-transmitting / semi-reflective electrode having the function of transmitting light, and the light-emitting device in this embodiment is second This is a top-emission type element that extracts light from electrode 102. Also, the second electrode 1 02 Above is the structure formula (vii) shown above, 4,4',4''-(benzene-1,3,5 - Triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II) is deposited at 70 nm. This improves the efficiency of retrieval.

[0469] The element structure of the light-emitting device 20 is summarized in the table below.

[0470] [Table 6]

[0471] Furthermore, the results of measuring the ordinary refractive index of BBA(βN2)B-03 and mmtBuBioFBi were obtained. This is shown in Figure 24. The measurement was performed using a spectroscopic ellipsometer (manufactured by J.A. Woolam Japan Co., Ltd.). The procedure was performed using the M-2000U. For the measurement sample, each layer of material was vacuum-deposited onto a quartz substrate. A film with a thickness of approximately 50 nm was used according to the method.

[0472] From the figure, BBA(βN2)B-03 and mmtBuBioFBi are 450nm to 650nm Within the nm range, it can be seen that the combinations have a difference of 0.2 or more and less than 0.5.

[0473] Furthermore, BBA(βN2)B was calculated from the results of cyclic voltammetry (CV) measurements. -03 and the HOMO levels of mmtBuBioFBi are N,N-dimethylformamide When (DMF) was the solvent, the values ​​were -5.47 eV and -5.42 eV, respectively. Therefore, the difference in HOMO levels between BBA(βN2)B-03 and mmtBuBioFBi is 0 It is less than 0.1 eV. The measurement device used for CV measurement is an electrochemical analyzer (B). Measurements will be taken using an ALS Model 600A or 600C (manufactured by A.S. Co., Ltd.). The solution, obtained by dissolving the material in a solvent, was measured.

[0474] The above light-emitting device is placed in a glove box under a nitrogen atmosphere, and the light-emitting device is exposed to the air. The process of sealing the element with a glass substrate to prevent exposure (applying UV-curable sealant around the element) The coating process involves irradiating only the sealing material with UV light, ensuring that the light-emitting device is not irradiated, and then applying atmospheric pressure. After heat treatment at 80°C for 1 hour (as shown below), the initial characteristics of these light-emitting devices were measured. They did that.

[0475] Figure 33 shows the brightness-current density characteristics of the light-emitting device 20, and Figure 34 shows the brightness-voltage characteristics. The rate-luminance characteristics are shown in Figure 35, the current density-voltage characteristics in Figure 36, and the blue index-luminance characteristics. The properties are shown in Figure 37, and the emission spectrum is shown in Figure 38. Also, 1000 cd / m² 2 in the vicinity The main characteristics are shown in Table 7. Note that luminance, CIE chromaticity, and emission spectrum measurements were performed using a spectrophotometer. Measurements were taken at room temperature using a radiometer (Topcon SR-UL1R).

[0476] [Table 7]

[0477] As shown in Figures 33 to 38 and Table 7, the light-emitting device 20 of one aspect of the present invention provides very good energy It was found to be a light-emitting device that exhibits flow efficiency and the Blue Index (BI). In particular, B I is very high at over 250 (cd / A / y), and the light-emitting device 20 exhibits particularly good BI emission. It can be called an optical device. Therefore, one aspect of the present invention is an optical device used in a display. It is particularly suitable for optical devices.

[0478] Furthermore, the current density is 50 mA / cm². 2 The graph shows the change in brightness with respect to operating time. As shown in 39, a light-emitting device 20 according to one aspect of the present invention is a reliable light-emitting device. I found out. [Examples]

[0479] This embodiment describes a light-emitting device 30, which is a light-emitting device according to one aspect of the present invention. The structural formulas of the organic compounds used in this example are shown below.

[0480] [ka]

[0481] (Method for fabricating the light-emitting device 30) First, silver (Ag) is sputtered onto a glass substrate as a reflective electrode. After forming a film with a thickness of nm, indium tin oxide (ITSO) containing silicon oxide is used as a transparent electrode. The first electrode 101 was formed by depositing a film with a thickness of 5 nm using the sputtering method. Oh, the electrode area is 4mm². 2 The dimensions were set to (2mm x 2mm). The first electrode 101 is transparent. It is an electrode and can be considered as the first electrode together with the reflective electrode mentioned above.

[0482] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface is washed with water, and 2 After firing at 0°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0483] Then, 10 -4 A substrate is introduced into a vacuum deposition apparatus where the internal pressure is reduced to approximately Pa, and then vacuum deposition is performed. After vacuum firing at 170°C for 30 minutes in the heating chamber of the apparatus, the substrate is left for approximately 30 minutes. It was allowed to cool.

[0484] Next, the first electrode 101 is formed such that the surface on which the first electrode 101 is formed faces downwards. The prepared substrate is fixed to a substrate holder provided inside the vacuum deposition apparatus, and on the first electrode 101, N-3',5'-ditterybutyl-1, represented by the above structural formula (ix), obtained by vapor deposition. ,1'-biphenyl-4-yl-N-1,1'-biphenyl-2-yl-9,9-dimethyl Lu-9H-fluoren-2-amine (abbreviation: mmtBuBioFBi) has a molecular weight of 672. A fluorine-containing electron acceptor material (OCHD-003) and a fluorine-containing electron acceptor material in a weight ratio of 1:0.1 (=m A hole injection layer is formed by co-depositing 10 nm of material to create mtBuBioFBi:OCHD-003. 111 was formed.

[0485] On the hole injection layer 111, a 42.5 nm layer of mmtBuBioFBi is used as the first layer, and a second layer is used. The layer is represented by the above structural formula (x) 4,4'-diphenyl-4''-(7;2'-bina Phthyl-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03) at 50 nm Then, a 40nm layer of mmtBuBioFBi is deposited as a third layer to form a hole transport layer 112. Ta.

[0486] Next, on the hole transport layer 112, N,N-bis[4-(di] represented by the above structural formula (xi) is added. [Benzofran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfB) An electron blocking layer was formed by depositing B1TP to a thickness of 10 nm.

[0487] Subsequently, 9-(1-naphthyl)-10-[4-(2-naphthyl], represented by the above structural formula (xii), is formed. [Phthyl)phenyl]anthracene (abbreviation: αN-βNPAnth) and the above structural formula (ii i) 3,10-bis[N-(9-phenyl-9H-carbazole-2-yl) -N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3.10PCA2Nbf(IV)-02) and αN-βN in a weight ratio of 1:0.015 (=αN-βN Co-deposit 20 nm so that PAnth:3,10PCA2Nbf(IV)-02) A light-emitting layer 113 was formed.

[0488] Subsequently, the 6-(1,1'-biphenyl-3-yl)- represented by the above structural formula (xiv) 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrim Din (abbreviated as 6mBP-4Cz2PPm) is deposited to a thickness of 10 nm to block holes. After forming the layer, the 2-[3-(2,6-dimethyl-3-pyri) represented by the above structural formula (v) Dinyl)-5-(9-phenantrenyl)phenyl]-4,6-diphenyl-1,3,5 -Triaidine (abbreviation: mPn-mDMePyPTzn) and the structure represented by the above structural formula (vi) 8-hydroxyquinolinatolithium (abbreviation: Liq) and 0.6 by weight ratio Co-depositing 20nm so that (=mPn-mDMePyPTzn:Liq) is performed for electron transport. Layer 114 was formed.

[0489] After the electron transport layer 114 is formed, lithium fluoride (LiF) is deposited to a thickness of 1 nm. A sub-injection layer 115 is formed, and finally, silver (Ag) and magnesium (Mg) are mixed in a volume ratio of 1:0 1. A second electrode 102 is formed by co-depositing to a film thickness of 15 nm, and the light-emitting device Chair 30 was manufactured. It also possesses both light-reflecting and light-transmitting properties. The reflective electrode, and the light-emitting device in this embodiment, extracts light from the second electrode 102. It is a mission-type element. Furthermore, an organic compound is used as a cap layer on the second electrode 102. The material is deposited at 65nm to improve extraction efficiency.

[0490] The element structure of the light-emitting device 30 is summarized in the table below.

[0491] [Table 8]

[0492] Furthermore, the results of measuring the ordinary refractive index of BBA(βN2)B-03 and mmtBuBioFBi were obtained. This is shown in Figure 24. The measurement was performed using a spectroscopic ellipsometer (manufactured by J.A. Woolam Japan Co., Ltd.). The procedure was performed using the M-2000U. For the measurement sample, each layer of material was vacuum-deposited onto a quartz substrate. A film with a thickness of approximately 50 nm was used according to the method.

[0493] From the figure, BBA(βN2)B-03 and mmtBuBioFBi are 450nm to 650nm Within the nm range, it can be seen that the combinations have a difference of 0.2 or more and less than 0.5.

[0494] Furthermore, BBA(βN2)B was calculated from the results of cyclic voltammetry (CV) measurements. -03 and the HOMO levels of mmtBuBioFBi are N,N-dimethylformamide When (DMF) was the solvent, the values ​​were -5.47 eV and -5.42 eV, respectively. Therefore, the difference in HOMO levels between BBA(βN2)B-03 and mmtBuBioFBi is 0 It is less than 0.1 eV. The measurement device used for CV measurement is an electrochemical analyzer (B). Measurements will be taken using an ALS Model 600A or 600C (manufactured by A.S. Co., Ltd.). The solution, obtained by dissolving the material in a solvent, was measured.

[0495] The above light-emitting device is placed in a glove box under a nitrogen atmosphere, and the light-emitting device is exposed to the air. The process of sealing the element with a glass substrate to prevent exposure (applying UV-curable sealant around the element) The coating process involves irradiating only the sealing material with UV light, ensuring that the light-emitting device is not irradiated, and then applying atmospheric pressure. After heat treatment at 80°C for 1 hour (as shown below), the initial characteristics of these light-emitting devices were measured. They did that.

[0496] Figure 40 shows the brightness-current density characteristics of the light-emitting device 30, and Figure 41 shows the brightness-voltage characteristics. The rate-luminance characteristics are shown in Figure 42, the current density-voltage characteristics in Figure 43, and the blue index-current density. The characteristics are shown in Figure 44, and the emission spectrum is shown in Figure 45. Furthermore, the 1000°C of the light-emitting device 30 is also shown. cd / m 2 Table 9 shows the main characteristics in the vicinity. Note that luminance, CIE chromaticity, and emission spectrum are also shown. A spectroradiometer (Topcon SR-UL1R) was used to measure the ketol content, and the measurements were taken at room temperature. .

[0497] [Table 9]

[0498] As shown in Figures 40 to 45 and Table 9, the light-emitting device 30 according to one aspect of the present invention has current efficiency and blue It was found to be a good light-emitting device for the index (BI). In particular, BI is 200 (cd / A / y) is very high, and the light-emitting device 30 is a particularly good light-emitting device for BI. Therefore, one aspect of the present invention is a light-emitting device used in a display. It is particularly suitable for this purpose.

[0499] Furthermore, the current density is 50 mA / cm². 2 The graph shows the change in brightness with respect to operating time. As shown in 46, the light-emitting device 30 according to one aspect of the present invention is a reliable light-emitting device. That's what I found out. [Examples]

[0500] In this embodiment, in the first hole transport layer, the second hole transport layer and the third hole transport layer, This section describes light-emitting devices 40 and 41, which have different GSP value sequences. The structural formulas of the organic compounds used in the examples are shown below.

[0501] [ka]

[0502] (Method for fabricating the light-emitting device 40) First, silver (Ag) is sputtered onto a glass substrate as a reflective electrode. After forming a film with a thickness of nm, indium tin oxide (ITSO) containing silicon oxide is used as a transparent electrode. The first electrode 101 was formed by depositing a film with a thickness of 5 nm using the sputtering method. Oh, the electrode area is 4mm². 2 The dimensions were set to (2mm x 2mm). The first electrode 101 is transparent. It is an electrode and can be considered as the first electrode together with the reflective electrode mentioned above.

[0503] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface is washed with water, and 2 After firing at 0°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0504] Then, 10 -4 A substrate is introduced into a vacuum deposition apparatus where the internal pressure is reduced to approximately Pa, and then vacuum deposition is performed. After vacuum firing at 170°C for 30 minutes in the heating chamber of the apparatus, the substrate is left for approximately 30 minutes. It was allowed to cool.

[0505] Next, the first electrode 101 is formed such that the surface on which the first electrode 101 is formed faces downwards. The prepared substrate is fixed to a substrate holder provided inside the vacuum deposition apparatus, and on the first electrode 101, N-3',5'-ditterybutyl-1, represented by the above structural formula (ix), obtained by vapor deposition. ,1'-biphenyl-4-yl-N-1,1'-biphenyl-2-yl-9,9-dimethyl Lu-9H-fluoren-2-amine (abbreviation: mmtBuBioFBi) has a molecular weight of 672. A fluorine-containing electron acceptor material (OCHD-003) and a fluorine-containing electron acceptor material in a weight ratio of 1:0.1 (=m A hole injection layer is formed by co-depositing 10 nm of material to create mtBuBioFBi:OCHD-003. 111 was formed.

[0506] On the hole injection layer 111, a 40 nm layer of mmtBuBioFBi is used as the first layer, and a second layer is used. The above structural formula (x) represents 4,4'-diphenyl-4''-(7;2'-binaphthin (Lu-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03) is 50 nm thick. A 40nm layer of mmtBuBioFBi was deposited as layer 3 to form a hole transport layer 112.

[0507] Next, on the hole transport layer 112, N,N-bis[4-(di] represented by the above structural formula (xi) is added. [Benzofran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfB) An electron blocking layer was formed by depositing B1TP to a thickness of 10 nm.

[0508] Subsequently, 9-(1-naphthyl)-10-[4-(2-naphthyl], represented by the above structural formula (xii), is formed. [Phthyl)phenyl]anthracene (abbreviation: αN-βNPAnth) and the above structural formula (ii i) 3,10-bis[N-(9-phenyl-9H-carbazole-2-yl) -N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3.10PCA2Nbf(IV)-02) and αN-βN in a weight ratio of 1:0.015 (=αN-βN Co-deposit 20 nm so that PAnth:3,10PCA2Nbf(IV)-02) A light-emitting layer 113 was formed.

[0509] Subsequently, the 6-(1,1'-biphenyl-3-yl)- represented by the above structural formula (xiv) 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrim Din (abbreviated as 6mBP-4Cz2PPm) is deposited to a thickness of 10 nm to block holes. After forming the layer, the structure represented by the above structural formula (xix) is 2-{(3',5'-di-tert- Butyl)-1,1'-biphenyl-3-yl}-4,6-diphenyl-1,3,5-tri Azine (abbreviation: mmtBumBPTzn) and 6-methyl- represented by the above structural formula (xx) 8-Quinolinolato-lithium (abbreviation: Li-6mq) and 8-Quinolinolato-lithium in a weight ratio of 1:1 (=mmtB The electron transport layer 114 is formed by co-depositing 20 nm of material such that it is umBPTzn:Li-6mq. I did it.

[0510] After the electron transport layer 114 is formed, lithium fluoride (LiF) is deposited to a thickness of 1 nm. A sub-injection layer 115 is formed, and finally, silver (Ag) and magnesium (Mg) are mixed in a volume ratio of 1:0 1. A second electrode 102 is formed by co-depositing to a film thickness of 15 nm, and the light-emitting device Chair 40 was fabricated. The second electrode has both the function of reflecting light and the function of transmitting light. The semi-transmissive / semi-reflective electrode in this embodiment takes light from the second electrode 102. It is a top-emission type element that emits emissions. Also, an organic compound is used on the second electrode 102. A 65nm capping layer is deposited to improve extraction efficiency.

[0511] (Method for fabricating the light-emitting device 41) The light-emitting device 41 has a first layer in the hole transport layer 112 of the light-emitting device 40 with the above structure The formula (xviii) represents N-(3'',5',5''-tri-tert-butyl-1 ,1':3',1''-terphenyl-4-yl)-N-(1,1'-biphenyl-2- (I)-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: mmtBumTPo The film was formed using FBi-04, and the thickness was reduced to 52.5 nm. Other than that, the light-emitting device... It was manufactured in the same way as Chair 40.

[0512] (Method for fabricating the comparative light-emitting device 40) The comparative light-emitting device 40 has a hole transport layer 112 and mmtBuBioFBi at 130 nm. The film was deposited in the desired manner, and the rest of the fabrication process was the same as for light-emitting device 40 or light-emitting device 41. did.

[0513] The element structures of light-emitting device 40, light-emitting device 41, and comparative light-emitting device 40 are shown in the following table. I summarized it here.

[0514] [Table 10]

[0515] [Table 11]

[0516] Also, mmtBuBioFBi, BBA(βN2)B-03 and mmtBumTPoF The results of measuring the ordinary refractive index of Bi-04 are shown in Figures 47(A) and (B). The measurement was performed using a spectroscopic ellipsoid. The measurement was performed using a Someter (M-2000U, manufactured by J.A. Woolam Japan). For the measurement sample, a film was used in which each layer of material was deposited on a quartz substrate by vacuum deposition, with a thickness of approximately 50 nm. I used it.

[0517] From the figure, BBA(βN2)B-03 and mmtBuBioFBi, BBA(βN2)B-0 3 and mmtBumTPoFBi-04 are in the range of 450nm to 650nm, respectively. This indicates that the combination has a refractive index difference of 0.2 or more and less than 0.5.

[0518] Furthermore, BBA(βN2)B was calculated from the results of cyclic voltammetry (CV) measurements. HOMO levels of -03, mmtBuBioFBi, and mmtBumTPoFBi-04 When N,N-dimethylformamide (DMF) is the solvent, the values ​​are -5.47 eV, respectively. The values ​​were -5.42 eV and -5.42 eV. From this, BBA(βN2)B-0 The difference in HOMO levels between 3 and mmtBuBioFBi and BBA(βN2)B-03 and mm The HOMO level differences for tBumTPoFBi-04 are each less than 0.1 eV. The measuring device used for CV measurement is an electrochemical analyzer (manufactured by BAS Corporation, model number) Using the ALS model 600A or 600C, the material to be measured is dissolved in a solvent to form a solution. We measured it.

[0519] Also, mmtBuBioFBi, BBA(βN2)B-03 and mmtBumTPoF The GSPs for Bi-04 are as shown in the table below. From the table below, the light-emitting device 40 is G In the device fabricated without considering SP, the light-emitting device 41 has the largest GSP in the third layer. The value is such that the difference between the GSP of the first layer and the GSP of the second layer is 10 (mV / nm) or less. As can be seen below, this is a light-emitting device fabricated with GSP in mind.

[0520] [Table 12]

[0521] The above light-emitting device is placed in a glove box under a nitrogen atmosphere, and the light-emitting device is exposed to the air. The process of sealing the element with a glass substrate to prevent exposure (applying UV-curable sealant around the element) The coating process involves irradiating only the sealing material with UV light, ensuring that the light-emitting device is not irradiated, and then applying atmospheric pressure. After heat treatment at 80°C for 1 hour (as shown below), the initial characteristics of these light-emitting devices were measured. They did that.

[0522] Brightness-current density characteristics of light-emitting device 40, light-emitting device 41, and comparative light-emitting device 40 Figure 48 shows the current efficiency-luminance characteristics, Figure 49 shows the luminance-voltage characteristics, and Figure 50 shows the current density-electrical Pressure characteristics are shown in Figure 51, blue index-luminance characteristics in Figure 52, and power efficiency-luminance characteristics in Figure 52. Figure 53 shows the emission spectrum, and Figure 54 shows the emission spectrum. Also, light-emitting device 40, light-emitting device 41 and the comparative light-emitting device 40 with a capacitance of 1000 cd / m² 2 Table 13 shows the main characteristics of the vicinity. Furthermore, a spectroradiometer (manufactured by Topcon Corporation) is used to measure luminance, CIE chromaticity, and emission spectrum. Measurements were taken at room temperature using an SR-UL1R. Power efficiency was calculated assuming a Lambertsian model. It is calculated using this method.

[0523] [Table 13]

[0524] Figures 48 to 54 and Table 13 show a light-emitting device 40 and light-emitting device 4 according to one embodiment of the present invention. Both device 1 and comparative light-emitting device 40 were found to be light-emitting devices with good characteristics. In particular, the light-emitting devices 40 and 41 having the configuration of the present invention are suitable for hole transport. A light-emitting device with good current efficiency and BI due to its structure consisting of a first to third layer. It can be seen that this is the case.

[0525] Now, comparing the light-emitting device 40 with the light-emitting device 4, we find that the light-emitting device 4 0 is the driving voltage due to the influence of interfacial resistance and other factors resulting from the three-layer structure of the hole transport layer 112. It can be seen that it is rising. However, because the current efficiency improvement effect of this structure is large, Even when the dynamic voltage is rising, the power efficiency of the light-emitting device 40 is higher than that of the comparative light-emitting device 40. It is.

[0526] On the other hand, the light-emitting device 41, in which the first to third layers are formed taking GSP into consideration, has hole transport Despite having a three-layer structure for layer 112, the driving voltage is low, and the hole transport layer is only one layer. It shows a lower value than the light device 40. As a result, the light-emitting device 41 is very good. It was found to be a light-emitting device that exhibits good power efficiency.

[0527] Furthermore, the current density is 50 mA / cm². 2 The graph shows the change in brightness with respect to operating time. As shown in 55. Light-emitting devices 40 and 41 according to one aspect of the present invention are comparative light-emitting devices It was found to be a more reliable light-emitting device compared to Vice 40. [Examples]

[0528] In this embodiment, in the first hole transport layer, the second hole transport layer and the third hole transport layer, This section describes light-emitting devices 50 and 51, which have different GSP value sequences. The structural formulas of the organic compounds used in the examples are shown below.

[0529] [ka]

[0530] (Method for fabricating the light-emitting device 50) First, silver (Ag) is sputtered onto a glass substrate as a reflective electrode. After forming a film with a thickness of nm, indium tin oxide (ITSO) containing silicon oxide is used as a transparent electrode. The first electrode 101 was formed by depositing a film with a thickness of 10 nm using the sputtering method. The electrode area is 4 mm². 2 The dimensions were set to (2mm x 2mm). The first electrode 101 was transparent. It is a light electrode and can be considered as the first electrode together with the reflective electrode mentioned above.

[0531] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface is washed with water, and 2 After firing at 0°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0532] Then, 10 -4 A substrate is introduced into a vacuum deposition apparatus where the internal pressure is reduced to approximately Pa, and then vacuum deposition is performed. After vacuum firing at 170°C for 30 minutes in the heating chamber of the apparatus, the substrate is left for approximately 30 minutes. It was allowed to cool.

[0533] Next, the first electrode 101 is formed such that the surface on which the first electrode 101 is formed faces downwards. The prepared substrate is fixed to a substrate holder provided inside the vacuum deposition apparatus, and on the first electrode 101, The above structural formula (xviii) is obtained by vapor deposition, resulting in N-(3'',5',5''-tri- tert-butyl-1,1':3',1''-terphenyl-4-yl)-N-(1,1 '-biphenyl-2-yl)-9,9-dimethyl-9H-fluoren-2-amine (abbreviation) :mmtBumTPoFBi-04) and an electron acceptor material containing fluorine with a molecular weight of 672. (OCHD-003) and (mmtBumTPoFBi-04) are in a weight ratio of 1:0.1. A hole injection layer 111 was formed by co-depositing 10 nm of material to create OCHD-003.

[0534] On the hole injection layer 111, mmtBumTPoFBi-04 is used as the first layer at a depth of 50 nm, Layer 2 is represented by the above structural formula (xxi) 3-(dibenzothiophen-4-yl)- 4'-phenyl-4''-(9-phenyl-9H-carbazole-2-yl)triphenyl Luamine (abbreviation: PCBBiPDBt-02) is used as the third layer at 50 nm, with the above structural formula ( N-(3',5'-di-tert-butyl-1,1'-biphenyl) represented as xxii -4-yl)-bis(9,9-dimethyl-9H-fluorene)-2,2'-amine (abbreviation) A hole transport layer 112 was formed by depositing 50 nm of (mmtBuBiFF).

[0535] Subsequently, the 11-(4-[1,1'-diphenyl]- represented by the above structural formula (xxiii) 4-yl-6-phenyl-1,3,5-triazine-2-yl)-11,12-dihydro -12-phenyl-indro[2,3-a]carbazole (abbreviation: BP-Icz(II)) Tzn) and 9-(2-naphthyl)-9'-phenyl represented by the above structural formula (xxiv) -9H,9'H-3,3'-bicarbazole (abbreviation: βNCCP) and the above structural formula (xx [2-d3-methyl-(2-pyridinyl-κN)benzofloxacin (v) is represented as [2-d3-methyl-(2-pyridinyl-κN)benzofloxacin (v) ]pyridine-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium ( III) (abbreviation: Ir(ppy)2(mbfpypy-d3)) and by weight ratio of 0.5: 0.5:0.1(=BP-Icz(II)Tzn:βNCCP:Ir(ppy)2(mb A light-emitting layer 113 was formed by co-depositing at a 40 nm depth so that it would be fpypy-d3).

[0536] Subsequently, the structure represented by the above structural formula (iv) is 2-[3'-(9,9-dimethyl-9H-full [Olen-2-yl)-1,1'-biphenyl-3-yl]-4,6-diphenyl-1,3 ,5-triazine (abbreviated as mFBPTzn) is deposited to a thickness of 10 nm to form a hole block. It forms a layer and is represented by the above structural formula (v) 2-[3-(2,6-dimethyl-3-pyridin [(nyl)-5-(9-phenantrenyl)phenyl]-4,6-diphenyl-1,3,5- Triazine (abbreviation: mPn-mDMePyPTzn) and the structure represented by the above structural formula (vi) 8-Hydroxyquinolinatolithium (abbreviation: Liq) and mPn in a weight ratio of 1:1 -mDMePyPTzn:Liq) is co-deposited at 25nm to create an electron transport layer 114. It was formed.

[0537] After the electron transport layer 114 is formed, lithium fluoride (LiF) is deposited to a thickness of 1 nm. A sub-injection layer 115 is formed, and finally, silver (Ag) and magnesium (Mg) are mixed in a volume ratio of 1:0 1. A second electrode 102 is formed by co-depositing to a film thickness of 15 nm, and the light-emitting device Chair 50 was manufactured. The second electrode has both the function of reflecting light and the function of transmitting light. The semi-transmissive / semi-reflective electrode in this embodiment takes light from the second electrode 102. It is a top-emission type element. Also, the above structural formula (v ii) 4,4',4''-(benzene-1,3,5-triyl)tri(dibenn Zothiophene (abbreviated as DBT3P-II) is deposited at a 70nm layer to improve extraction efficiency. It is.

[0538] (Method for fabricating the comparative light-emitting device 50) The comparison light-emitting device 50 is the mmtBumTPoFBi-04 and PCB of the light-emitting device 50. Aside from replacing the BiPDBt-02, the device was fabricated in the same manner as the light-emitting device 50.

[0539] The element structures of the light-emitting device 50 and the comparative light-emitting device 50 are summarized in the table below.

[0540] [Table 14]

[0541] Also, mmtBumTPoFBi-04, PCBBiPDBt-02 and mmtBuB The results of measuring the ordinary refractive index of iFF are shown in Figures 62(A) and (B). The measurement was performed using spectroscopic ellipsomometry. The measurement was performed using a router (M-2000U, manufactured by J.A. Woolam Japan Co., Ltd.). For the sample used, a film was prepared by depositing each layer of material onto a quartz substrate using a vacuum deposition method, with each layer having a thickness of approximately 50 nm. Ta.

[0542] From the figure, the hole transport layer of the light-emitting device 50 has a high refractive index in the second of three layers, and the first layer is approximately It can be seen that the third layer is a light-emitting device with a low refractive index. On the other hand, comparative light-emitting device 50 In this case, the first layer of the three hole transport layers has a high refractive index, while the second and third layers have low refractive indices. It is a light-emitting device.

[0543] Furthermore, mmtBumTPo calculated from the results of cyclic voltammetry (CV) measurements The HOMO levels of FBi-04, PCBBiPDBt-02, and mmtBuBiFF are: When N,N-dimethylformamide (DMF) is the solvent, the values ​​are -5.42 eV and -5, respectively. The values ​​were 0.48eV and -5.33eV. From this, mmtBumTPoFBi- The difference in HOMO levels between 04 and PCBBiPDBt-02, and PCBBiPDBt-02 and mm The difference in HOMO levels of tBuBiFF and mmtBumTPoFBi-04 and mmtBu The difference in HOMO levels between BiFFs is less than 0.2 eV each. Note that the measurement equipment used for CV measurement and Therefore, an electrochemical analyzer (manufactured by BAS Corporation, model number: ALS Model 600) Using A or 600C, the solution obtained by dissolving the material to be measured in the solvent was measured.

[0544] Also, mmtBumTPoFBi-04, PCBBiPDBt-02 and mmtBuB The GSPs of the iFF are as shown in the table below. From the table below, the light-emitting device 50 is the third Consider the GSP of the layer with the largest value and the GSP of the first layer with the smallest value. It is clear that this light-emitting device was fabricated with consideration. On the other hand, the comparative light-emitting device 50 is the third The GSP of the first layer is the largest, but the value obtained by subtracting the GSP of the second layer from the GSP of the first layer is 10( It is a light-emitting device with a light emission of mV / nm or higher.

[0545] [Table 15]

[0546] The above light-emitting device is placed in a glove box under a nitrogen atmosphere, and the light-emitting device is exposed to the air. The process of sealing the element with a glass substrate to prevent exposure (applying UV-curable sealant around the element) The coating process involves irradiating only the sealing material with UV light, ensuring that the light-emitting device is not irradiated, and then applying atmospheric pressure. After heat treatment at 80°C for 1 hour (as shown below), the initial characteristics of these light-emitting devices were measured. They did that.

[0547] Figure 56 shows the luminance-current density characteristics of the light-emitting device 50 and the comparative light-emitting device 50. Voltage characteristics are shown in Figure 57, current efficiency-luminance characteristics in Figure 58, and current density-voltage characteristics in Figure 59. The power efficiency-luminance characteristics are shown in Figure 60, and the emission spectrum is shown in Figure 61. Furthermore, the light-emitting device... 50 and 50 comparison light-emitting devices with 1000 cd / m² 2 Table 16 shows the main characteristics of the vicinity. This is shown. Note that a spectroradiometer (Topcon Corporation) is used to measure luminance, CIE chromaticity, and emission spectrum. The measurements were taken at room temperature using a (manufactured by SR-UL1R) device. Power efficiency was measured using the Lambertian method. This is calculated based on assumptions.

[0548] [Table 16]

[0549] Figures 56 to 61 and Table 16 show a light-emitting device 50 and a comparative light-emitting device according to one aspect of the present invention. The Vice 50 devices were found to be light-emitting devices with excellent characteristics. In particular, the present invention The light-emitting device 50 having the configuration is such that the hole transport layer is a first layer as shown in Embodiment 1. It has been found that the light-emitting device has good current efficiency because it is composed of three layers. Furthermore, the light-emitting device 50 has GSPs in the first to third layers such that the first layer < second layer <As it is the third layer, the drive voltage is low and the light emission device has very good power efficiency. It became a chair. [Examples]

[0550] This embodiment describes a light-emitting device 60, which is a light-emitting device according to one aspect of the present invention. The light-emitting device 60 is a tandem type light-emitting device having multiple light-emitting layers connected by a charge generation layer. This is a device. The structural formulas of the organic compounds used in this example are shown below.

[0551] [ka]

[0552] (Method for fabricating the light-emitting device 60) First, silver (Ag) is sputtered onto a glass substrate as a reflective electrode. After forming a film with a thickness of nm, indium tin oxide (ITSO) containing silicon oxide is used as a transparent electrode. The first electrode 101 was formed by depositing a film with a thickness of 5 nm using the sputtering method. Oh, the electrode area is 4mm². 2 The size was set to (2mm x 2mm). The transparent electrode was used as the anode. It can be considered as the first electrode 101 together with the above-mentioned reflective electrode.

[0553] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface is washed with water, and 2 After firing at 0°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0554] Then, 10 -4 A substrate is introduced into a vacuum deposition apparatus where the internal pressure is reduced to approximately Pa, and then vacuum deposition is performed. After vacuum firing at 170°C for 30 minutes in the heating chamber of the apparatus, the substrate is left for approximately 30 minutes. It was allowed to cool.

[0555] Next, the substrate is placed in the vacuum deposition apparatus so that the surface on which the first electrode 101 is formed faces downwards. The above structural formula (xvii) is fixed to the holder and deposited onto the first electrode 101 by vapor deposition. i) N-(3'',5',5''-tri-tert-butyl-1,1':3' represented by ,1''-terphenyl-4-yl)-N-(1,1'-biphenyl-2-yl)-9, 9-Dimethyl-9H-Fluorene-2-amine (abbreviation: mmtBumTPoFBi-04) ) and an electron acceptor material (OCHD-003) with a molecular weight of 672 and containing fluorine, in a weight ratio So that it becomes 1:0.1 (=mmtBumTPoFBi-04:OCHD-003) A hole injection layer was formed by co-depositing a 0 nm layer.

[0556] On the hole injection layer, a 35nm layer of mmtBumTPoFBi-04 is used as the first layer, and the second layer... As shown in the above structural formula (xi), N,N-bis[4-(dibenzofuran-4-yl) Phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB1TP) is 50 nm thick. Layer 3 is represented by the above structural formula (ix) N-3',5'-ditterybutyl-1 ,1'-biphenyl-4-yl-N-1,1'-biphenyl-2-yl-9,9-dimethyl Lu-9H-fluoren-2-amine (abbreviation: mmtBuBioFBi) is deposited at a 40 nm depth. , a hole transport layer A was formed.

[0557] Next, DBfBB1TP is deposited on hole transport layer A to a thickness of 10 nm to block electrons. Layer A was formed.

[0558] Subsequently, 9-(1-naphthyl)-10-[4-(2-naphthyl], represented by the above structural formula (xii), is formed. [Phthyl)phenyl]anthracene (abbreviation: αN-βNPAnth) and the above structural formula (xi ii) 2,12-di(tert-butyl)-5,9-di(4-tert-butyl (ruphenyl)-N,N-diphenyl-5H,9H-[1,4]benzazabolino[2,3 ,4-kl]phenazavolin-7-amine (abbreviation: DPhA-tBu4DABNA) , by weight ratio 1:0.015 (=αN-βNPAnth:DPhA-tBu4DABNA) A light-emitting layer A was formed by co-depositing a 20nm layer in such a manner.

[0559] Subsequently, the 6-(1,1'-biphenyl-3-yl)- represented by the above structural formula (xiv) 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrim Din (abbreviated as 6mBP-4Cz2PPm) is deposited to a thickness of 10 nm to block holes. After forming layer A, 2,9-di(2-naphthyl)-4,7 represented by the above structural formula (xv) -Diphenyl-1,10-phenanthroline (abbreviation: NBPhen) will be 20 nm long. An electron transport layer A was formed by depositing it onto sea urchin.

[0560] After forming electron transport layer A, lithium oxide (Li2O) is deposited at a thickness of 0.1 nm, and the above structure is further formed. The formula (xxvii) represents N-(1,1'-biphenyl-4-yl)-N-[4-(9 -phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H- Luolen-2-amine (abbreviation: PCBBiF) and OCHD-003 are mixed in a weight ratio of 1:0 A 10nm co-deposited layer is created to form a charge generation layer with a density of 0.1 (=PCBBiF:OCHD-003). It formed.

[0561] A 40 nm layer of PCBBiF was deposited on the charge generation layer to form a hole transport layer B.

[0562] Next, DBfBB1TP is deposited on hole transport layer B to a thickness of 10 nm to block electrons. Lay...

Claims

1. It comprises a first electrode, a second electrode, a light-emitting layer, an electron transport layer, a first layer, a second layer, and a third layer. The first layer is located between the first electrode and the second layer. The second layer is located between the first layer and the third layer. The third layer is located between the second layer and the light-emitting layer. The light-emitting layer is located between the third layer and the electron transport layer. The electron transport layer is located between the light-emitting layer and the second electrode. The first layer comprises a first organic compound, The second layer comprises a second organic compound, The aforementioned third layer contains a third organic compound, The electron transport layer comprises a heterocyclic compound having a triazine skeleton and an alkali metal complex. A light-emitting device in which the paraphotometric refractive index of the second organic compound at any wavelength between 450 nm and 650 nm is higher than the paraphotometric refractive index of the first organic compound at the said wavelength and the paraphotometric refractive index of the third organic compound at the said wavelength.

2. It comprises a first electrode, a second electrode, a light-emitting layer, an electron transport layer, a first layer, a second layer, and a third layer. The first layer is located between the first electrode and the second layer. The second layer is located between the first layer and the third layer. The third layer is located between the second layer and the light-emitting layer. The light-emitting layer is located between the third layer and the electron transport layer. The electron transport layer is located between the light-emitting layer and the second electrode. The first layer comprises a first organic compound, The second layer comprises a second organic compound, The aforementioned third layer contains a third organic compound, The electron transport layer comprises a heterocyclic compound having a triazine skeleton and an alkali metal complex. A light-emitting device in which the paraphotometric refractive index of the second organic compound at any wavelength between 455 nm and 465 nm is higher than the paraphotometric refractive index of the first organic compound at the same wavelength and the paraphotometric refractive index of the third organic compound at the same wavelength.

3. It comprises a first electrode, a second electrode, a light-emitting layer, an electron transport layer, a first layer, a second layer, and a third layer. The first layer is located between the first electrode and the second layer. The second layer is located between the first layer and the third layer. The third layer is located between the second layer and the light-emitting layer. The light-emitting layer is located between the third layer and the electron transport layer. The electron transport layer is located between the light-emitting layer and the second electrode. The first layer comprises a first organic compound, The second layer comprises a second organic compound, The aforementioned third layer contains a third organic compound, The electron transport layer comprises a heterocyclic compound having a triazine skeleton and an alkali metal complex. A light-emitting device in which the paraphotometric refractive index of the second organic compound at a wavelength of 633 nm is higher than that of the first organic compound at a wavelength of 633 nm and the paraphotometric refractive index of the third organic compound at a wavelength of 633 nm.

4. It comprises a first electrode, a second electrode, a light-emitting layer, an electron transport layer, a first layer, a second layer, and a third layer. The first layer is located between the first electrode and the second layer. The second layer is located between the first layer and the third layer. The third layer is located between the second layer and the light-emitting layer. The light-emitting layer is located between the third layer and the electron transport layer. The electron transport layer is located between the light-emitting layer and the second electrode. The light-emitting layer includes a light-emitting material that exhibits light emission with a peak wavelength of wavelength λnm, The first layer comprises a first organic compound, The second layer comprises a second organic compound, The aforementioned third layer contains a third organic compound, The electron transport layer comprises a heterocyclic compound having a triazine skeleton and an alkali metal complex. A light-emitting device in which the paraphotometric refractive index of the second organic compound at the wavelength λnm is higher than that of the first organic compound at the wavelength λnm and the paraphotometric refractive index of the third organic compound at the wavelength λnm.

5. In claim 4, A light-emitting device in which the difference between the paraphotometric refractive index of the second organic compound at the wavelength λnm and the paraphotometric refractive index of the first organic compound at the wavelength λnm, and the difference between the paraphotometric refractive index of the second organic compound at the wavelength λnm and the paraphotometric refractive index of the third organic compound at the wavelength λnm are each 0.2 or more and less than 0.

5.

6. In claim 5, A light-emitting device in which the difference in the ordinary refractive index of the first organic compound and the third organic compound at the wavelength λnm is 0.1 or less.

7. In claim 5 or claim 6, The product of the film thickness of the second layer and the ordinary refractive index of the second organic compound at the wavelength λnm is, A light-emitting device having a wavelength of 70% to 130% of 1 / 4 of the aforementioned wavelength λnm.

8. In any one of claims 1 to 7, A light-emitting device in which the difference between the HOMO level of the first organic compound and the HOMO level of the third organic compound is 0.2 eV or less.

9. In any one of claims 1 to 8, A light-emitting device in which the difference between the HOMO level of the first organic compound and the HOMO level of the second organic compound is 0.2 eV or less.

10. In any one of claims 1 to 9, The third layer of the light-emitting device does not contain fluorine.

11. In any one of claims 1 to 10, A light-emitting device in which the film thickness of each of the first to third layers is 25 nm or more and 70 nm or less.

12. In any one of claims 1 to 11, A light-emitting device in which the thickness of the second layer is greater than the thickness of the first layer and the thickness of the third layer.

13. In any one of claims 1 to 12, A light-emitting device in which the first layer and the second layer are in contact, and the second layer and the third layer are in contact.

14. In any one of claims 1 to 13, A light-emitting device in which the first electrode includes a reflective electrode.

15. In any one of claims 1 to 14, A light-emitting device in which the value obtained by subtracting the potential gradient (GSP) (mV / nm) of the surface potential of the third layer from the potential gradient (GSP) (mV / nm) of the surface potential of the second layer is 10 (mV / nm) or less.

16. In any one of claims 1 to 15, A light-emitting device in which the value obtained by subtracting the potential gradient (GSP) (mV / nm) of the surface potential of the third layer from the potential gradient (GSP) (mV / nm) of the surface potential of the first layer is 10 (mV / nm) or less.

17. In any one of claims 1 to 16, A light-emitting device in which the potential gradient (GSP) (mV / nm) of the surface potential of the third layer is greater than the potential gradient (GSP) (mV / nm) of the surface potential of the second layer.

18. In any one of claims 1 to 17, A light-emitting device in which the potential gradient (GSP) (mV / nm) of the surface potential of the third layer is greater than the potential gradient (GSP) (mV / nm) of the surface potential of the first layer.

19. In any one of claims 1 to 18, A light-emitting device in which the potential gradient (GSP) (mV / nm) of the surface potential of the second layer is greater than the potential gradient (GSP) (mV / nm) of the surface potential of the first layer.

20. A light-emitting device according to any one of claims 1 to 19, A display device having at least one of a sensor, an operating button, a speaker, and a microphone.

21. A light-emitting device according to any one of claims 1 to 19, An electronic device having at least one of a sensor, an operating button, a speaker, and a microphone.

22. A light-emitting device according to any one of claims 1 to 19, A light-emitting device having at least one of a transistor and a substrate.

23. A lighting device comprising a light-emitting device according to any one of claims 1 to 19 and a housing.

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