Organometallic complex and light-emitting device

Abstract

To provide a novel organometallic complex excellent in utility or reliability, and a light-emitting device.SOLUTION: An organometallic complex represented by the general formula (G1) is provided. In the formula, R1, R2 and R4 to R22 each independently represent hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, where at least one of R2 and R4 represents an alkyl group having 1 to 10 carbon atoms, and where one or more of R18 to R22 each represent an alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.SELECTED DRAWING: None

Description

[Technical field]

[0001] An embodiment of the present invention relates to an organometallic complex, an organic compound, a light-emitting device, a light-receiving device, a light-receiving and light-emitting device, a light-emitting device, a light-receiving and light-emitting device, a display device, an electronic device, a lighting device, and an electronic device. Note that an embodiment of the present invention is not limited to the above technical field. A technical field of an embodiment of the invention disclosed in the present specification and the like relates to an object, a method, or a manufacturing method. Alternatively, an embodiment of the present invention relates to a process, a machine, a manufacture, or a composition of matter. Therefore, more specifically, examples of the technical field of an embodiment of the present invention disclosed in the present specification include a semiconductor device, a display device, a liquid crystal display device, a light-emitting device, a lighting device, a power storage device, a storage device, an imaging device, a driving method thereof, or a manufacturing method thereof. [Background technology]

[0002] 2. Description of the Related Art Organic EL devices (organic EL elements), which are typified by light-emitting devices, light-receiving devices, and light-receiving / light-emitting devices that utilize electroluminescence (EL) using organic compounds, are being put into practical use.

[0003] For example, the basic structure of a light-emitting device is a pair of electrodes sandwiching an organic compound layer (EL layer) containing a light-emitting material. By applying a voltage to this device, carriers are injected, and the recombination energy of the carriers is utilized to emit light from the light-emitting material.

[0004] The basic structure of a light-receiving device is a pair of electrodes sandwiching an organic compound layer (active layer) containing a photoelectric conversion material. This device absorbs light energy and generates carriers, which can obtain electrons from the photoelectric conversion material.

[0005] For example, a functional panel is known in which pixels provided in a display region include a light-emitting element (light-emitting device) and a photoelectric conversion element (light-receiving device) (Patent Document 1).

[0006] Thus, displays and lighting devices using organic EL devices are suitable for use in a variety of electronic devices, and research and development is ongoing to develop organic EL devices with better efficiency and life span.

[0007] Although the characteristics of organic EL devices have been improved remarkably, they are still insufficient to meet high demands for all characteristics, including efficiency and durability. In particular, to solve problems such as burn-in, which are unique to organic EL devices, it is better to minimize the decrease in efficiency due to degradation.

[0008] Degradation is largely dependent on the luminescent center substance and the materials around it, so there has been active development of organic compound materials, including organometallic complexes, that have good properties. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] WO2020 / 152556 Summary of the Invention [Problem to be solved by the invention]

[0010] An object of one embodiment of the present invention is to provide a novel organometallic complex. Another object of one embodiment of the present invention is to provide an organometallic complex whose excited state is stable. Another object of one embodiment of the present invention is to provide an organometallic complex that can be used as a light-emitting material. Another object of one embodiment of the present invention is to provide an organometallic complex that is easy to synthesize. Another object of one embodiment of the present invention is to provide a light-emitting device having a long operating lifetime. Another object of one embodiment of the present invention is to provide a light-emitting device with a small voltage change during operation. Another object of one embodiment of the present invention is to provide a novel light-emitting device. Another object of one embodiment of the present invention is to reduce the manufacturing cost of the light-emitting device. Another object of one embodiment of the present invention is to provide a light-emitting device, electronic device, or lighting device with low power consumption.

[0011] Another object of one embodiment of the present invention is to provide an organometallic complex having a selectively deuterated partial structure, to perform molecular design that can reduce the complexity of a synthetic route, the need for high temperature and high pressure in the synthesis, and to synthesize an organometallic complex molecularly designed in such a manner.

[0012] Note that the description of these problems does not preclude the existence of other problems. Note that one embodiment of the present invention does not necessarily solve all of these problems. Note that problems other than these will become apparent from the description of the specification, drawings, claims, etc., and it is possible to extract problems other than these from the description of the specification, drawings, claims, etc. [Means for solving the problem]

[0013] One embodiment of the present invention is an organometallic complex represented by the following general formula (G1).

[0014] [ka]

[0015] In the above general formula (G1), R 1, R 2 , and R 4 ~R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents an alkyl group having 1 to 10 carbon atoms; 18 ~R 22 At least one of the above represents a substituted or unsubstituted alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0016] Or, in the above general formula (G1), R 1 , R 2 , and R 4 ~R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents a deuterium-containing alkyl group having 1 to 10 carbon atoms; 18 ~R 22 At least one of the above represents an alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0017] Or, in the above general formula (G1), R 1 , R 2 , and R 4 ~R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 represents an alkyl group having 1 to 10 carbon atoms; R 18 ~R 22 At least one of the above represents an alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0018] Or, in the above general formula (G1), R 1 , R 2 , and R4 ~R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 represents an alkyl group having 1 to 10 carbon atoms and a deuterium atom; R 18 ~R 22 At least one of the above represents an alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0019] Or, in the above general formula (G1), R 1 , R 2 , R 4 ~R 18 , R 20 , and R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents an alkyl group having 1 to 10 carbon atoms; 19 and R 21 each independently represents an alkyl group having 3 to 10 carbon atoms.

[0020] Or, in the above general formula (G1), R 1 , R 2 , and R 4 ~R 18 , R 20 , and R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents a deuterium-containing alkyl group having 1 to 10 carbon atoms; 19 and R 21 each independently represents an alkyl group having 3 to 10 carbon atoms.

[0021] Or, in the above general formula (G1), R 1 , R 2 , and R 4 ~R22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents an alkyl group having 1 to 10 carbon atoms; 18 ~R 22 At least one of the above represents the following general formula (R-1).

[0022] [ka]

[0023] In the above general formula (R-1), R 31 ~R 35 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0024] Or, in the above general formula (G1), R 1 , R 2 , R 4 ~R 17 and R 19 ~R 21 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents an alkyl group having 1 to 10 carbon atoms; 18 and R 22 Any one of the above represents the general formula (R-1). In the general formula (R-1), R 31 ~R 35 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0025] Or, in the above general formula (G1), R 1 , R 2 , R 4 ~R 11 , R 13~R 17 and R 19 ~R 21 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents an alkyl group having 1 to 10 carbon atoms; 12 represents an alkyl group having 1 to 10 carbon atoms; R 18 and R 22 Any one of the above represents the general formula (R-1). In the general formula (R-1), R 31 ~R 35 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0026] One embodiment of the present invention is an organometallic complex represented by the following structural formula (100), structural formula (115), structural formula (119), structural formula (120), or structural formula (121).

[0027] [ka]

[0028] One embodiment of the present invention is a light-emitting device using any of the above-described organometallic complexes.Also, a light-emitting device including a light-emitting device using any of the above-described organometallic complexes and a light-receiving device.

[0029] Another embodiment of the present invention is a light-emitting device including the light-emitting device having any of the above structures and a transistor or a substrate.

[0030] Another embodiment of the present invention is an electronic device including a light-emitting device having any of the above structures and a detection unit, an input unit, or a communication unit.

[0031] Another embodiment of the present invention is a lighting device including a light-emitting device having any of the above structures and a housing. Effect of the Invention

[0032] According to one embodiment of the present invention, a novel organometallic complex can be provided. According to one embodiment of the present invention, an organometallic complex having a stable excited state can be provided. According to one embodiment of the present invention, an organometallic complex that can be used as a light-emitting material can be provided. According to one embodiment of the present invention, an organometallic complex that can be easily synthesized can be provided. According to one embodiment of the present invention, a novel light-emitting device can be provided. According to one embodiment of the present invention, a light-emitting device having a long operating lifetime can be provided. According to one embodiment of the present invention, a light-emitting device having a small voltage change during operation can be provided. According to one embodiment of the present invention, the manufacturing cost of the light-emitting device can be reduced. According to one embodiment of the present invention, a light-emitting device, electronic device, or lighting device having low power consumption can be provided.

[0033] Note that the description of these effects does not preclude the existence of other effects. Note that one embodiment of the present invention does not necessarily have all of these effects. Note that effects other than these will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract effects other than these from the description in the specification, drawings, claims, etc. [Brief description of the drawings]

[0034] [Figure 1] 1(A) and 1(B) are diagrams illustrating the configuration of a light-emitting device according to an embodiment. [Diagram 2] 2A to 2E are diagrams illustrating a configuration of a light-emitting device according to an embodiment. [Diagram 3] 3(A) and 3(B) are a top view and a cross-sectional view of the light emitting device. [Figure 4] 4(A) to 4(D) are diagrams showing a light emitting device. [Diagram 5] 5A to 5E are cross-sectional views showing an example of a method for manufacturing a light-emitting device. [Figure 6]6A to 6E are cross-sectional views showing an example of a method for manufacturing a light-emitting device. [Figure 7] 7A to 7C are cross-sectional views showing an example of a method for manufacturing a light-emitting device. [Figure 8] 8A to 8C are cross-sectional views showing an example of a method for manufacturing a light-emitting device. [Figure 9] 9A to 9C are cross-sectional views showing an example of a method for manufacturing a light-emitting device. [Figure 10] 10A to 10C are cross-sectional views showing an example of a method for manufacturing a light-emitting device. [Figure 11] 11A to 11C are cross-sectional views showing an example of a method for manufacturing a light-emitting device. [Figure 12] 12A to 12G are top views showing configuration examples of pixels. [Figure 13] 13A to 13I are top views showing configuration examples of pixels. [Figure 14] 14(A) and 14(B) are perspective views showing configuration examples of a display module. [Figure 15] 15(A) and 15(B) are cross-sectional views showing configuration examples of a light emitting device. [Figure 16] FIG. 16 is a perspective view showing a configuration example of a light emitting device. [Figure 17] Fig. 17A is a cross-sectional view showing a configuration example of a light-emitting device, Fig. 17B and Fig. 17C are cross-sectional views showing configuration examples of a transistor. [Figure 18] FIG. 18 is a cross-sectional view showing an example of the configuration of a light emitting device. [Figure 19] 19A to 19D are cross-sectional views showing configuration examples of a light emitting device. [Figure 20] 20A to 20D are diagrams illustrating examples of electronic devices. [Figure 21] 21A to 21F are diagrams illustrating examples of electronic devices. [Figure 22]22A to 22G are diagrams showing examples of electronic devices. [Figure 23] FIG. 23 shows the 1H NMR spectrum of the organometallic complex prepared in the example. [Figure 24] FIG. 24 is a diagram illustrating the absorption spectrum and emission spectrum of the organometallic complex prepared in the example. [Diagram 25] FIG. 25 is a diagram illustrating the thermogravimetry-differential thermal analysis of the organometallic complexes prepared in the examples. [Figure 26] FIG. 26 is a diagram illustrating the configuration of a device according to an embodiment. [Figure 27] FIG. 27 is a diagram illustrating the luminance-current density characteristics of a device according to an embodiment. [Figure 28] FIG. 28 is a diagram illustrating the luminance-voltage characteristics of the device according to the embodiment. [Figure 29] FIG. 29 is a diagram illustrating the current efficiency-current density characteristics of the device according to the embodiment. [Diagram 30] FIG. 30 is a diagram illustrating the current density-voltage characteristics of the device according to the example. [Diagram 31] FIG. 31 is a diagram illustrating the power efficiency-current density characteristics of the device according to the embodiment. [Diagram 32] FIG. 32 is a diagram illustrating the external quantum efficiency-current density characteristics of the device according to the embodiment. [Diagram 33] FIG. 33 is a diagram illustrating the emission spectrum of the device according to the example. [Diagram 34] FIG. 34 is a diagram showing the change in luminance with respect to the driving time of the sample according to the example. [Diagram 35] FIG. 35 shows the 1H NMR spectrum of the organometallic complex prepared in the example. [Diagram 36] FIG. 36 is a diagram illustrating the absorption spectrum and emission spectrum of the organometallic complex prepared in the example. [Figure 37] FIG. 37 is a diagram illustrating the absorption spectrum and emission spectrum of the organometallic complex prepared in the example. [Figure 38]FIG. 38 is a diagram illustrating the luminance-current density characteristics of a device according to an example. [Figure 39] FIG. 39 is a diagram illustrating the luminance-voltage characteristics of a device according to an embodiment. [Diagram 40] FIG. 40 is a diagram illustrating the current efficiency-current density characteristics of the device according to the embodiment. [Diagram 41] FIG. 41 is a diagram illustrating the current density-voltage characteristics of the device according to the example. [Diagram 42] FIG. 42 is a diagram illustrating the BI-current density characteristics of the device according to the embodiment. [Diagram 43] FIG. 43 is a diagram illustrating the external quantum efficiency-current density characteristics of the device according to the embodiment. [Diagram 44] FIG. 44 is a diagram illustrating the emission spectrum of the device according to the embodiment. [Diagram 45] FIG. 45 is a diagram illustrating the luminance-current density characteristics of a device according to an embodiment. [Figure 46] FIG. 46 is a diagram illustrating the luminance-voltage characteristics of a device according to an embodiment. [Figure 47] FIG. 47 is a diagram illustrating the current efficiency-luminance characteristics of a device according to an embodiment. [Figure 48] FIG. 48 is a diagram illustrating the current density-voltage characteristics of the device according to the example. [Figure 49] FIG. 49 is a diagram illustrating the BI-current density characteristics of the device according to the embodiment. [Figure 50] FIG. 50 is a diagram illustrating the emission spectrum of the device according to the embodiment. [Figure 51] FIG. 51 is a diagram for explaining the configuration of a device according to an embodiment. [Figure 52] FIG. 52 is a diagram illustrating the luminance-current density characteristics of a device according to an embodiment. [Diagram 53] FIG. 53 is a diagram illustrating the luminance-voltage characteristics of a device according to an embodiment. [Figure 54] FIG. 54 is a diagram illustrating the current efficiency-current density characteristics of the device according to the embodiment. [Figure 55] FIG. 55 is a diagram illustrating the current density-voltage characteristics of the device according to the example. [Figure 56] FIG. 56 is a diagram illustrating the BI-current density characteristics of the device according to the embodiment. [Figure 57] FIG. 57 is a diagram illustrating the emission spectrum of the device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] (Embodiment 1) In this embodiment, an organometallic complex which is one embodiment of the present invention and a light-emitting device using the organometallic complex will be described.

[0036] <Example of light-emitting device configuration> First, a structure of a light-emitting device of one embodiment of the present invention will be described below with reference to FIGS.

[0037] FIG. 1(A) is a schematic cross-sectional view of a light-emitting device 10 according to one embodiment of the present invention.

[0038] The light-emitting device 10 has a pair of electrodes (a first electrode 101 and a second electrode 102) and an organic compound layer 103 provided between the pair of electrodes. The organic compound layer 103 has at least a light-emitting layer 113.

[0039] In addition to the light-emitting layer 113, the organic compound layer 103 shown in FIG. 1A has functional layers such as a hole-injection layer 111, a hole-transporting layer 112, an electron-transporting layer 114, and an electron-injection layer 115.

[0040] In the present embodiment, the first electrode 101 of the pair of electrodes is described as an anode and the second electrode 102 as a cathode, but the configuration of the light-emitting device 10 is not limited to this. That is, the first electrode 101 may be a cathode and the second electrode 102 may be an anode, and the layers between the electrodes may be stacked in the reverse order. That is, the order of stacking from the anode side may be the hole injection layer 111, the hole transport layer 112, the light-emitting layer 113, the electron transport layer 114, and the electron injection layer 115.

[0041] 1A, the organic compound layer 103 may have at least one selected from a hole-injection layer 111, a hole-transport layer 112, an electron-transport layer 114, and an electron-injection layer 115. Alternatively, the organic compound layer 103 may have a functional layer having a function of reducing a hole or electron injection barrier, improving the transportability of holes or electrons, inhibiting the transportability of holes or electrons, suppressing a quenching phenomenon caused by an electrode, or the like. Each functional layer may be a single layer or a stack of multiple layers.

[0042] Fig. 1(B) is a schematic cross-sectional view showing an example of the light-emitting layer 113 shown in Fig. 1(A). The light-emitting layer 113 shown in Fig. 1(B) has a host material 118 (organic compounds 118_1 and 118_2) and a guest material 119.

[0043] In addition, a light-emitting organometallic complex may be used as the guest material 119, and the light-emitting organometallic complex is preferably a substance that can emit phosphorescence (hereinafter, also referred to as a phosphorescent compound). In the following description, a structure in which an organometallic complex is used as the guest material 119 will be described.

[0044] In the present invention, an organometallic complex having platinum (Pt) as a central metal is used as the guest material 119. The organometallic complex used in the present invention has a pyridine ring, and the pyridine ring has an alkyl group. In addition, the pyridine ring has a phenyl group at the 4-position.

[0045] In an organometallic complex having a pyridine ring, an alkyl group is introduced to a carbon atom having a high spin density in a triplet excited state, and the stability of the compound in the excited state can be improved. In addition, the alkyl group is preferably deuterated. A deuterated alkyl group is introduced to a carbon atom where the LUMO distribution is concentrated, and the stability of the compound in a state where an electron is received by the LUMO, i.e., in a reduced state, can be improved.

[0046] In addition, the introduction of a phenyl group to the carbon atom adjacent to the carbon atom where the LUMO distribution is concentrated can broaden the LUMO distribution, and also stabilize the LUMO, improving the stability of the compound in a reduced state.

[0047] Furthermore, the alkyl group can exert a steric hindrance effect on the phenyl group. In particular, when the alkyl group is deuterated, the stability can be improved. Furthermore, the rotation of the phenyl group can be suppressed, and the thermal properties of the compound, such as sublimability, can be improved. Furthermore, the vibration of the compound can be suppressed, and thermal deactivation from the excited state can be suppressed. Furthermore, high luminous efficiency can be achieved. Furthermore, the shape of the emission spectrum can be adjusted by selecting the ligand or the ligand's substituent. Furthermore, the thermal properties of the compound, such as sublimability, can be improved. As a result, a novel organometallic complex with excellent usefulness or reliability can be provided.

[0048] In addition, the pyridine ring of the organometallic complex has an alkyl group. This allows the bond dissociation energy of the compound to be greater than the bond dissociation energy of the carbon-hydrogen bond by utilizing the carbon-deuterium bond. In addition, the molecular structure can be stabilized. In addition, bond dissociation within the compound structure in an excited state can be suppressed. In addition, deterioration or alteration of the compound due to dissociation of the carbon-deuterium bond can be suppressed. Note that when the hydrogen of the alkyl group is deuterated, the above-mentioned effects can be further enhanced.

[0049] Therefore, for example, the organometallic complex of the present invention can be suitably used in the light-emitting layer of a light-emitting device. Also, for example, the organometallic complex of the present invention can be suitably used in a layer in contact with the light-emitting layer of a light-emitting device. By using the organometallic complex in a light-emitting device, the reliability can be improved.

[0050] <Examples of organometallic complexes> One embodiment of the present invention is an organometallic complex having platinum (Pt) as a central metal, which is represented by the following general formula: An organometallic complex having platinum (Pt) is a substance that can be very suitably used as a material for a light-emitting device.

[0051] One embodiment of the present invention is an organometallic complex represented by General Formula (G1).

[0052] [ka]

[0053] In the above general formula (G1), R 1 , R 2 , and R 4 ~R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents an alkyl group having 1 to 10 carbon atoms; 18 ~R 22 At least one of the above represents an alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0054] In addition, R 2 or R 4 In the alkyl group having 1 to 10 carbon atoms that substitutes for the phenyl group, some or all of the hydrogen atoms in the alkyl group may be deuterium. By introducing an alkyl group having deuterium into the carbon atom adjacent to the phenyl group, the LUMO distribution can be broadened.

[0055] In particular, in the above general formula (G1), R 2 R preferably represents an alkyl group having 1 to 10 carbon atoms and a deuterium atom. 2 The presence of deuterium makes it difficult for the carbon-deuterium bond to dissociate. A deuterated alkyl group is introduced to the carbon atom where the LUMO distribution is concentrated, improving the stability of the compound in the state where an electron is accepted by the LUMO, i.e., in the reduced state.

[0056] In addition, in the above general formula (G1), R 19 and R 21 preferably represents an alkyl group having 3 to 10 carbon atoms. This suppresses the rotation of the phenyl group, and improves the thermal properties of the compound, such as sublimability. In addition, it suppresses thermal deactivation of the molecules and makes it difficult for intermolecular interactions to occur, thereby improving the quantum yield and the luminous efficiency of the element.

[0057] Also, R 18 ~R 22 Any one or more of the above may represent the following general formula (R-1).

[0058] [ka]

[0059] In the above general formula (R-1), R 31 ~R 35 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0060] In addition, R 18 ~R 22 In particular, any one of R 18 and R 22 is preferably represented by the above general formula (R-1). 12 preferably represents an alkyl group having 1 to 10 carbon atoms.

[0061] In the above general formula (G1), R 1 , R 2 , R 4 ~R 22 , and R 31 ~R 35 Examples of the alkyl group represented by the formula (I) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a neopentyl group, a hexyl group, an isohexyl group, a 3-methylpentyl group, a 2-methylpentyl group, a 2-ethylbutyl group, a 1,2-dimethylbutyl group, and a 2,3-dimethylbutyl group.

[0062] Also, R 1 , R 2 , R 4 ~R 22 , and R 31 ~R 35 Examples of the aryl group represented by the formula (I) include a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthryl group, a tetracenyl group, a benzanthracenyl group, a triphenylenyl group, a pyrenyl group, and a spirobi[9H-fluorenyl]-yl group.

[0063] Also, R 1 , R 2 , R 4 ~R 22 , and R 31 ~R 35 When any of the groups has a substituent, the substituent is an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an aryl group having 6 to 13 carbon atoms.

[0064] <Example> Next, specific examples of the organometallic complex which has the structure represented by General Formula (G1) and is one embodiment of the present invention will be shown below.

[0065] [ka]

[0066] [ka]

[0067] [ka]

[0068] The organometallic complexes represented by the above structural formulas (100) to (121) are examples of the organometallic complexes represented by the above general formula (G1); however, the organometallic complexes of one embodiment of the present invention are not limited thereto.

[0069] <Method of synthesizing organometallic complexes> The following describes a method for synthesizing the organometallic complex represented by the general formula (G1). Various reactions can be applied to synthesize the organometallic complex. For example, the organometallic complex represented by the general formula (G1) can be synthesized by the following simple synthesis scheme.

[0070] <<Synthesis method 1>> First, the pyridylcarbazole derivative represented by (A1), which is the starting material for the organometallic complex represented by general formula (G1), can be synthesized by the following synthesis scheme (s1-1). The pyridylcarbazole derivative (A'1) in which phenylbenzimidazole is ether-bridged can be reacted with a hypervalent iodine reagent (A'2) to obtain the pyridylcarbazole derivative (A1).

[0071] [ka]

[0072] In the above synthesis scheme (s1-1), R 1 , R 2 , and R 4 ~R 22each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents a deuterium-containing alkyl group having 1 to 10 carbon atoms; 18 ~R 22 At least one of the above represents a substituted or unsubstituted alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0073] Next, the organometallic complex represented by the general formula (G1) can be obtained by reacting the pyridylcarbazole derivative (A1) obtained in the above synthetic scheme (s1-1) with a platinum compound containing a halogen (dichloro(1,5-cyclooctadiene)platinum(II), etc.), as shown in the synthetic scheme (s1-2).

[0074] [ka]

[0075] In the above synthesis scheme (s1-2), R 1 , R 2 , and R 4 ~R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents a deuterium-containing alkyl group having 1 to 10 carbon atoms; 18 ~R 22 At least one of the above represents an alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0076] <<Synthesis method 2>> In addition, for example, the organometallic complex represented by the general formula (G1) can be synthesized by the following simple synthesis scheme.

[0077] First, the pyridylcarbazole derivative represented by (B1), which is the starting material for the organometallic complex represented by general formula (G1), can be synthesized by the following synthesis scheme (s2-1). The pyridylcarbazole derivative (B'1) in which a diamine compound is ether-bridged is reacted with triethyl orthoformate to cyclize it to obtain the compound represented by (B'2), and then the pyridylcarbazole derivative (B1) can be obtained by ion exchange with ammonium hexafluorophosphate.

[0078] [ka]

[0079] In the above synthesis scheme (s2-1), R 1 , R 2 , and R 4 ~R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents a deuterium-containing alkyl group having 1 to 10 carbon atoms; 18 ~R 22 At least one of the above represents an alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0080] Next, the organometallic complex represented by the general formula (G1) can be obtained by reacting the pyridylcarbazole derivative (B1) obtained in the above synthetic scheme (s2-1) with a platinum compound containing a halogen (dichloro(1,5-cyclooctadiene)platinum(II), etc.), as shown in the synthetic scheme (s2-2).

[0081] [ka]

[0082] In the above synthesis scheme (s2-2), R 1 , R 2, and R 4 ~R 22 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R 2 or R 4 At least one of R represents a deuterium-containing alkyl group having 1 to 10 carbon atoms; 18 ~R 22 At least one of the following represents an alkyl group having 3 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.

[0083] Since various types of the compounds (A'1), (A'2), (B'1), and (B'2) can be synthesized, many types of organometallic complexes represented by General Formula (G1) can be synthesized. Thus, the organometallic complex of one embodiment of the present invention has a feature of being rich in variation.

[0084] Although an example of a method for synthesizing an organometallic complex that is a compound of one embodiment of the present invention has been described above, the present invention is not limited to this method, and any other synthesis method may be used for synthesis.

[0085] Note that the compound described in this embodiment can be used in appropriate combination with any of the structures described in other embodiment modes.

[0086] (Embodiment 2) In this embodiment, a structure of a light-emitting device using the organometallic complex described in Embodiment 1 will be described with reference to FIGS.

[0087] <Basic structure of light-emitting device> The basic structure of a light-emitting device will be described. Figure 2(A) shows a light-emitting device having a structure (single structure) in which an organic compound layer including a light-emitting layer is disposed between a pair of electrodes. Specifically, the device has a structure in which an organic compound layer 103 is sandwiched between a first electrode 101 and a second electrode 102.

[0088] 2B shows a light-emitting device having a stacked structure (tandem structure) in which a plurality of organic compound layers (103a, 103b) (two layers in FIG. 2B) are provided between a pair of electrodes and a charge generation layer 106 is provided between the organic compound layers. A light-emitting device with a tandem structure can realize a highly efficient light-emitting device without changing the amount of current.

[0089] The charge generation layer 106 has a function of injecting electrons into one organic compound layer (103a or 103b) and injecting holes into the other organic compound layer (103b or 103a) when a potential difference is generated between the first electrode 101 and the second electrode 102. Therefore, in FIG. 2(B), when a voltage is applied to the first electrode 101 so that the potential is higher than that of the second electrode 102, electrons are injected from the charge generation layer 106 into the organic compound layer 103a and holes are injected into the organic compound layer 103b.

[0090] From the viewpoint of light extraction efficiency, the charge generation layer 106 is preferably transparent to visible light (specifically, the visible light transmittance of the charge generation layer 106 is 40% or more). The charge generation layer 106 functions even if it has a lower conductivity than the first electrode 101 and the second electrode 102.

[0091] FIG. 2C shows a stacked structure of an organic compound layer 103 of a light-emitting device according to one embodiment of the present invention. In this case, the first electrode 101 functions as an anode, and the second electrode 102 functions as a cathode. The organic compound layer 103 has a structure in which a hole injection layer 111, a hole transport layer 112, a light-emitting layer 113, an electron transport layer 114, and an electron injection layer 115 are stacked in this order over the first electrode 101. Note that the light-emitting layer 113 may have a structure in which a plurality of light-emitting layers having different light emission colors are stacked. For example, a light-emitting layer containing a red light-emitting substance, a light-emitting layer containing a green light-emitting substance, and a light-emitting layer containing a blue light-emitting substance are stacked, or a layer having a carrier transport material is interposed between the light-emitting layers. Alternatively, a light-emitting layer containing a yellow light-emitting substance and a light-emitting layer containing a blue light-emitting substance may be combined. However, the stacked structure of the light-emitting layer 113 is not limited to the above. For example, the light-emitting layer 113 may have a structure in which a plurality of light-emitting layers having the same light-emitting color are stacked. For example, a first light-emitting layer containing a blue light-emitting material and a second light-emitting layer containing a blue light-emitting material are stacked, or a layer having a carrier transporting material is interposed between the first light-emitting layer and the second light-emitting layer. In the case of a structure in which a plurality of light-emitting layers having the same light-emitting color are stacked, reliability may be improved more than that of a single layer structure. In addition, even in the case of a tandem structure having a plurality of organic compound layers as shown in FIG. 2B, each organic compound layer is stacked in order from the anode side as described above. In addition, when the first electrode 101 is a cathode and the second electrode 102 is an anode, the stacking order of the organic compound layers 103 is reversed. Specifically, the structure is such that 111 on the first electrode 101, which is a cathode, is an electron injection layer, 112 is an electron transport layer, 113 is a light-emitting layer, 114 is a hole transport layer, and 115 is a hole injection layer.

[0092] The light-emitting layer 113 included in the organic compound layers (103, 103a, 103b) each contains a light-emitting substance and a combination of multiple substances, and can be configured to emit fluorescent or phosphorescent light of a desired emission color. The light-emitting layer 113 may have a stacked structure with different emission colors. In this case, different materials may be used for the light-emitting substance and other substances used in each stacked light-emitting layer. A structure in which different emission colors are emitted from the multiple organic compound layers (103a, 103b) shown in Figure 2(B) may also be used. In this case, different materials may be used for the light-emitting substance and other substances used in each light-emitting layer.

[0093] In addition, in a light-emitting device according to one embodiment of the present invention, for example, the first electrode 101 shown in FIG. 2C is a reflective electrode, the second electrode 102 is a semi-transmissive and semi-reflective electrode, and a micro-optical resonator (microcavity) structure is formed, whereby light emitted from the light-emitting layer 113 included in the organic compound layer 103 is resonated between the two electrodes, and the light emitted from the second electrode 102 can be strengthened. Therefore, it is easy to realize high definition. In addition, the light emission intensity of a specific wavelength in the front direction can be strengthened, and therefore low power consumption can be achieved.

[0094] In addition, when the first electrode 101 of the light-emitting device is a reflective electrode having a laminated structure of a conductive material having reflectivity and a conductive material having light transmission (transparent conductive film), optical adjustment can be performed by controlling the film thickness of the transparent conductive film. Specifically, it is preferable to adjust the optical distance (product of film thickness and refractive index) between the first electrode 101 and the second electrode 102 to mλ / 2 (where m is an integer of 1 or more) or its vicinity, for the wavelength λ of light obtained from the light-emitting layer 113.

[0095] In order to amplify the desired light (wavelength: λ) obtained from the light-emitting layer 113, it is preferable to adjust the optical distance from the first electrode 101 to the region (light-emitting region) in the light-emitting layer 113 where the desired light is obtained and the optical distance from the second electrode 102 to the region (light-emitting region) in the light-emitting layer 113 where the desired light is obtained to (2m'+1)λ / 4 (where m' is an integer of 1 or more) or close thereto. Note that the light-emitting region referred to here refers to a recombination region of holes and electrons in the light-emitting layer 113.

[0096] By carrying out such optical adjustment, it is possible to narrow the spectrum of the specific monochromatic light obtained from the light-emitting layer 113, and to obtain light emission with excellent color purity.

[0097] However, in the above case, the optical distance between the first electrode 101 and the second electrode 102 can be strictly said to be the total thickness from the reflection area in the first electrode 101 to the reflection area in the second electrode 102. However, since it is difficult to strictly determine the reflection area in the first electrode 101 and the second electrode 102, it is assumed that the above-mentioned effect can be sufficiently obtained by assuming any position of the first electrode 101 and the second electrode 102 as the reflection area. Furthermore, the optical distance between the first electrode 101 and the light-emitting layer from which the desired light is obtained can be strictly said to be the optical distance between the reflection area in the first electrode 101 and the light-emitting area in the light-emitting layer from which the desired light is obtained. However, since it is difficult to strictly determine the reflection area in the first electrode 101 and the light-emitting area in the light-emitting layer from which the desired light is obtained, it is assumed that the above-mentioned effect can be sufficiently obtained by assuming any position of the first electrode 101 as the reflection area and any position of the light-emitting layer from which the desired light is obtained as the light-emitting area.

[0098] The light-emitting device shown in Figure 2(D) has a tandem structure. The tandem structure can be used to produce a light-emitting device capable of emitting high-luminance light. In addition, the tandem structure can reduce the current required to obtain the same luminance compared to a single structure, and therefore can improve reliability. In addition, power consumption can be reduced.

[0099] The light-emitting device shown in FIG. 2(E) is an example of the light-emitting device with the tandem structure shown in FIG. 2(B), and has a structure in which three organic compound layers (103a, 103b, 103c) are stacked with charge generating layers (106a, 106b) sandwiched therebetween, as shown in the figure. The three organic compound layers (103a, 103b, 103c) each have a light-emitting layer (113a, 113b, 113c), and the light-emitting colors of the light-emitting layers can be freely combined. For example, the light-emitting layer 113a can be blue, the light-emitting layer 113b can be red, green, or yellow, and the light-emitting layer 113c can be blue, but it is also possible to make the light-emitting layer 113a red, the light-emitting layer 113b blue, green, or yellow, and the light-emitting layer 113c red.

[0100] In the light-emitting device according to one embodiment of the present invention described above, at least one of the first electrode 101 and the second electrode 102 is an electrode having translucency (such as a transparent electrode or a semi-transparent / semi-reflective electrode). When the electrode having translucency is a transparent electrode, the visible light transmittance of the transparent electrode is 40% or more. When the electrode is a semi-transparent / semi-reflective electrode, the visible light reflectance of the semi-transparent / semi-reflective electrode is 20% or more and 80% or less, preferably 40% or more and 70% or less. Furthermore, these electrodes have a resistivity of 1×10 -2 It is preferable to set it to Ωcm or less.

[0101] In the above-described light-emitting device according to one embodiment of the present invention, when one of the first electrode 101 and the second electrode 102 is a reflective electrode (reflective electrode), the electrode has a visible light reflectance of 40% to 100%, preferably 70% to 100%. -2 It is preferable to set it to Ωcm or less.

[0102] <Specific structure of light-emitting device> Next, a specific structure of the light-emitting device according to one embodiment of the present invention will be described. In addition, a tandem structure will be described here with reference to FIG. 2(D). The single-structure light-emitting devices shown in FIG. 2(A) and FIG. 2(C) also have the same organic compound layer structure. When the light-emitting device shown in FIG. 2(D) has a microcavity structure, the first electrode 101 is formed as a reflective electrode, and the second electrode 102 is formed as a semi-transmissive and semi-reflective electrode. Therefore, a single or multiple desired electrode materials can be used to form a single layer or a stacked layer. The second electrode 102 is formed by selecting an appropriate material after forming the organic compound layer 103b.

[0103] <Light-emitting device materials> <Light-emitting layer> The light-emitting layers (113, 113a, 113b) are layers containing a light-emitting substance. As the light-emitting substance that can be used for the light-emitting layers (113, 113a, 113b), a substance that emits light of a color such as blue, purple, blue-purple, green, yellow-green, yellow, orange, or red can be appropriately used. When the light-emitting layer has multiple light-emitting layers, a structure that emits different light colors (for example, white light emission obtained by combining light-emitting colors that are complementary to each other) can be obtained by using different light-emitting substances for each light-emitting layer. Furthermore, a stacked structure in which one light-emitting layer contains different light-emitting substances may be used.

[0104] Furthermore, the light-emitting layers (113, 113a, 113b) may contain one or more types of organic compounds (host materials, etc.) in addition to the light-emitting substance (guest material).

[0105] Specifically, the structure described with reference to FIG. 1B in Embodiment 1 can be used as the light-emitting layer 113. In the light-emitting layer 113, the host material 118 is present in the largest amount by weight, and the guest material 119 (phosphorescent compound) is dispersed in the host material 118. The T1 level of the host material 118 (organic compound 118_1 and organic compound 118_2) of the light-emitting layer 113 is preferably higher than the T1 level of the guest material of the light-emitting layer 113 (guest material 119).

[0106] As the organic compound 118_1, a material having a higher electron transporting property than a hole transporting property of 1×10 -6 cm 2 It is preferable that the material has an electron mobility of 1000 nm or more / Vs. As a material that easily receives electrons (a material having electron transport properties), a compound having a π-electron-deficient heteroaromatic ring skeleton such as a nitrogen-containing heteroaromatic compound, and a zinc or aluminum-based metal complex can be used. Examples of compounds having a π-electron-deficient heteroaromatic ring skeleton include oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, phenanthroline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and triazine derivatives. Examples of zinc or aluminum-based metal complexes include metal complexes having a quinoline ligand, a benzoquinoline ligand, an oxazole ligand, or a thiazole ligand.

[0107] Specific examples include metal complexes having a quinoline skeleton or a benzoquinoline skeleton, such as tris(8-quinolinolato)aluminum(III) (abbreviation: Alq), tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviation: Almq3), bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq2), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), and bis(8-quinolinolato)zinc(II) (abbreviation: Znq). In addition, metal complexes having oxazole or thiazole ligands, such as bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO) and bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ), can also be used. In addition to metal complexes, 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 9-[4-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)phenyl] -9H-carbazole (abbreviation: CzTAZ1), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), bathophenanthroline (abbreviation: BPhen), bathocuproine (abbreviation: BCP), and other heterocyclic compounds, 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mCzBPDBq), 2-[4-(3,6-diphenyl-9H-carbazol-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(dibenzothiophene-4-yl)phenyl]dibenzo[f,h]quinoxaline 6-[3-(dibenzothiophene-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 2-[3-(3,9'-bi-9H-carbazol-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mCzCzPDBq), 4,6-bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6- Heterocyclic compounds with a diazine skeleton, such as bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II) and 4,6-bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm), and 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCC Heterocyclic compounds having a triazine skeleton such as 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy) and 1,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB) and other heterocyclic compounds having a pyridine skeleton such as 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (abbreviation: BzOs) can also be used. Among the above-mentioned heterocyclic compounds, heterocyclic compounds having a triazine skeleton, a diazine (pyrimidine, pyrazine, pyridazine) skeleton, or a pyridine skeleton are preferred because they are stable and reliable. In addition, heterocyclic compounds having such skeletons have high electron transport properties and contribute to reducing the driving voltage. In addition, poly(2,5-pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,Polymer compounds such as poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviation: PF-Py) and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviation: PF-BPy) can also be used. The substances mentioned here are mainly 1×10, -6 cm 2 A substance having an electron mobility of 1 / Vs or more. Note that any substance other than the above may be used as long as it has a higher electron transporting property than a hole transporting property.

[0108] The organic compound 118_2 is preferably a combination capable of forming an exciplex with the organic compound 118_1. Specifically, it is preferable that the organic compound 118_2 has a highly donor skeleton such as a π-electron-rich heteroaromatic ring skeleton or an aromatic amine skeleton. Examples of compounds having a π-electron-rich heteroaromatic ring skeleton include heteroaromatic compounds such as dibenzothiophene derivatives, dibenzofuran derivatives, and carbazole derivatives. In this case, it is preferable to select the organic compound 118_1, the organic compound 118_2, and the guest material 119 (phosphorescent compound) so that the emission peak of the exciplex formed by the organic compound 118_1 and the organic compound 118_2 overlaps with the absorption band of the triplet MLCT (Metal to Ligand Charge Transfer) transition of the guest material 119 (phosphorescent compound), more specifically, with the absorption band located at the longest wavelength. This makes it possible to obtain a light-emitting device with dramatically improved luminous efficiency. However, when a thermally activated delayed fluorescent material is used instead of the phosphorescent compound, it is preferable that the absorption band located at the longest wavelength is a singlet absorption band.

[0109] As the organic compound 118_2, the following hole transporting materials can be used.

[0110] As the hole transporting material, a material having a higher hole transporting property than that of electrons can be used. -6 cm 2It is preferable that the hole transport material is a material having a hole mobility of 1 / Vs or more. Specifically, aromatic amines, carbazole derivatives, aromatic hydrocarbons, stilbene derivatives, etc. can be used. The hole transport material may be a polymer compound.

[0111] Specific examples of these materials with high hole transport properties include aromatic amine compounds such as N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis[4-bis(3-methylphenyl)aminophenyl]-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviation: DNTPD), and 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B).

[0112] Specific examples of the carbazole derivative include 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA2), and 3,6-bis[N-(4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTP N2), 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), and the like can be mentioned.

[0113] Other examples of carbazole derivatives that can be used include 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), and 1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene.

[0114] Examples of aromatic hydrocarbons include 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA), 2-tert -butyl-9,10-bis[2-(1-naphthyl)phenyl]anthracene, 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene, 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene, 9,9'-bianthryl, 10,10'-diphenyl-9,9'-bianthryl, 10,10'-bis(2-phenylphenyl)-9,9'-bianthryl, 10,10'-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9'-bianthryl, anthracene, tetracene, rubrene, perylene, 2,5,8,11-tetra(tert-butyl)perylene, etc. In addition, pentacene, coronene, etc. can also be used. In this way, 1 × 10 -6 cm 2 It is more preferable to use an aromatic hydrocarbon having a hole mobility of 1 / Vs or more and a carbon number of 14 or more and 42 or less.

[0115] The aromatic hydrocarbon may have a vinyl skeleton. Examples of aromatic hydrocarbons having a vinyl skeleton include 4,4'-bis(2,2-diphenylvinyl)biphenyl (abbreviation: DPVBi) and 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviation: DPVPA).

[0116] In addition, polymer compounds such as poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviation: PTPDMA), or poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviation: Poly-TPD) can also be used.

[0117] Furthermore, examples of materials with high hole transport properties include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB or α-NPD), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviation: TPD), 4,4',4''-tris(carbazol-9-yl)triphenylamine (abbreviation: TCTA), 4,4',4''-tris[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviation: 1'-TNATA), 4,4',4''-Tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA), 4,4',4''-Tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: m-MTDATA), N,N'-bis(9,9'-spirobi[9H-fluoren]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl mBPAFLP), N-(9,9-dimethyl-9H-fluoren-2-yl)-N-{9,9-dimethyl-2-[N'-phenyl-N'-(9,9-dimethyl-9H-fluoren-2-yl)amino]-9H-fluoren-7-yl}phenylamine (DFLADFL), N-(9,9-dimethyl-2-diphenylamino-9H-fluoren-7-yl)diphenylamine (DPNF), N-(9,9-spirobi[9 H-fluorenyl]-2-yl)-N,N'N'-triphenyl-1,4-phenylenediamine (abbreviation: DPASF), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-Di(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), 4-phenyldiphenyl-(9-phenyl-9H-carbazol-3-yl)amine (abbreviation: PCA1BP), N,N'-bis(9-phenylcarbazol-3-yl)-N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N,N',N''-triphenyl-N,N',N''-tris(9-phenylcarbazol-3-yl)benzene-1,3,5-triamine amine (abbreviation: PCA3B), N-(9,9-diphenyl-9H-fluoren-2-yl)-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: PCAFLP(2)), N-(9,9-diphenyl-9H-fluoren-2-yl)-N,9-diphenyl-9H-carbazol-2-amine (abbreviation: PCAFLP(2)-02), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-carbazol-3-amine (abbreviation: PCBiF), N-(biphenyl- 4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9′-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF), N-(9,9-spirobi[9H-fluorene]-2-amine N,N'-diphenyl-N,N'-bis(4-diphenylaminophenyl)spirobi[9H-fluorene]-2,7-diamine (abbreviation: DPA2SF), N-[4-(9H-carbazol-9-yl)phenyl]-N-(4-phenyl)phenylaniline (abbreviation: YGA1BP), N,N'-bis[4-(carbazol-9-yl)phenyl]-N,N'-diphenyl-9,9-dimethylfluorene-2,Aromatic amine compounds such as 7-diamine (abbreviation: YGA2F) can be used. In addition, 3-[4-(1-naphthyl)phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 9-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]phenanthrene (abbreviation: PCPPn), 3,3'-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP), 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 3,6-bis(3,5-diphenylfuran) and the like can be used. phenyl)-9-phenylcarbazole (abbreviation: CzTP), 3,6-di(9H-carbazol-9-yl)-9-phenyl-9H-carbazole (abbreviation: PhCzGI), 2,8-di(9H-carbazol-9-yl)dibenzothiophene (abbreviation: Cz2DBT), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-I I), 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II), 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV), 4-[3-(triphenylen-2-yl)phenyl]dibenzothiophene (abbreviation: mDBTPTp-II) and other amine compounds, carbazole compounds, thiophene compounds, furan compounds, fluorene compounds, triphenylene compounds, phenanthrene compounds, and the like can be used. Among the above-mentioned compounds, compounds having a pyrrole skeleton, a furan skeleton, a thiophene skeleton, or an aromatic amine skeleton are preferred because they are stable and reliable. In addition, compounds having such skeletons have high hole transport properties and contribute to reducing the driving voltage.

[0118] Furthermore, a substance that exhibits fluorescent emission (fluorescent substance) can be further used in the light-emitting layer. In this case, the excitation energy of the phosphorescent substance in the light-emitting layer is transferred to the fluorescent substance, resulting in light emission. The fluorescent substance allows transition from the singlet excited state to the singlet ground state, so its excitation lifetime (light-emitting lifetime) is shorter than that of the phosphorescent substance. Therefore, by further using a fluorescent substance in the light-emitting layer, a stable and reliable light-emitting device can be manufactured.

[0119] Examples of fluorescent substances include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, naphthalene derivatives, etc. Fluorescent substances whose singlet excitation energy levels and triplet excitation energy levels are lower than the triplet excitation energy levels of the phosphorescent substance can be used.

[0120] Specific examples include 5,6-bis[4-(10-phenyl-9-anthryl)phenyl]-2,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-anthryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9 H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA) , N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra-tert-butylperylene (abbreviation: TBP), 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1-phenylene)bis(N,N',N'-triphenyl-1,4-phenyl diamine) (abbreviation: DPABPA), N,N,N',N',N'',N'',N''',N'''-Octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), Coumarin 30, N,N'-Diphenyl-N,N'-(1,6-pyrene-diyl)bis[(6-phenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03), 3,10-Bis[N-(9-phenyl-9H-carbazol-2-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10PCA2Nbf(IV)-02), 3,10-bis[N-(dibenzofuran-3-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10FrA2Nbf(IV)-02), etc.;

[0121] In addition, 5,9-diphenyl-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracene (abbreviation: DABNA1), 9-[(1,1'-diphenyl)-3-yl]-N,N,5,11-tetraphenyl-5,9-dihydro-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracene-3-amine (abbreviation: DABNA2), 2,12-di(tert-butyl)-5,9-di(4-tert-butylphenyl) -N,N-diphenyl-5H,9H-[1,4]benzazaborino[2,3,4-kl]phenazaborin-7-amine (abbreviation: DPhA-tBu4DABNA), 2,12-di(tert-butyl)-N,N,5,9-tetra(4-tert-butylphenyl)-5H,9H-[1,4]benzazaborino[2,3,4-kl]phenazaborin-7-amine (abbreviation: tBuDPhA-tBu4DABNA), 2,12-di(tert-butyl) N7,N7,N13,N13,5,9,11,15-octaphenyl-5H,9H,11H,15H-[1,4]benzazaborino[2,3,4-kl][1,4]benzazaborino[4',3',2':4,5][1,4]benzazaborino[ Condensed heteroaromatic compounds containing nitrogen and boron, such as 3,2-b]phenazaborine-7,13-diamine (abbreviation: ν-DABNA) and 2-(4-tert-butylphenyl)benz[5,6]indolo[3,2,1-jk]benzo[b]carbazole (abbreviation: tBuPBibc), in particular compounds having a diaza-boranaphtho-anthracene skeleton, are suitable for use because they have a narrow emission spectrum and can emit blue light with good color purity.

[0122] In addition to these, 9,10,11-tris[3,6-bis(1,1-dimethylethyl)-9H-carbazol-9-yl]-2,5,15,18-tetrakis(1,1-dimethylethyl)indolo[3,2,1-de]indolo[3',2',1':8,1][1,4]benzazaborino[2,3,4-kl]phenazaborine (abbreviation: BBCz-G), 9,11-bis[3,6-bis(1,1-dimethylethyl)-9H-carbazol-9-yl]-2,5,15,18-tetrakis(1,1-dimethylethyl)indolo[3,2,1-de]indolo[3',2',1':8,1][1,4]benzazaborino[2,3,4-kl]phenazaborine (abbreviation: BBCz-Y) and the like can be preferably used.

[0123] In addition, a thermally activated delayed fluorescence (TADF) material can be used as the light-emitting material contained in the light-emitting layer. As the thermally activated delayed fluorescence material, a heterocyclic compound having a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring can be used. Specific examples include 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 2-[4-(10H-phenoxazin-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4 -(5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthen-9-one (abbreviation: ACRXTN), bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridin-9,9'-anthracene]-10'-one (abbreviation: ACRSA), etc. The heterocyclic compound has a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring, and therefore has high electron transport properties and hole transport properties, making it preferable. Among the skeletons having a π-electron-deficient heteroaromatic ring, a diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton) or a triazine skeleton is preferred because it is stable and reliable. In addition, among the skeletons having a π-electron-rich heteroaromatic ring, an acridine skeleton, a phenoxazine skeleton, a thiophene skeleton, a furan skeleton, and a pyrrole skeleton are stable and reliable, so it is preferred to have one or more selected from these skeletons. Note that, as the pyrrole skeleton, an indole skeleton, a carbazole skeleton, and a 3-(9-phenyl-9H-carbazol-3-yl)-9H-carbazole skeleton are particularly preferred.In addition, a substance in which a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring are directly bonded is particularly preferable because the donor property of the π-electron rich heteroaromatic ring and the acceptor property of the π-electron deficient heteroaromatic ring are both strong, and the difference between the singlet excitation energy level and the triplet excitation energy level is small. In addition, the compound having the above-mentioned diaza-boranaphtho-anthracene skeleton is also suitable because it functions as a thermally activated delayed fluorescent material and can emit blue light with good color purity.

[0124] Alternatively, a thermally activated delayed fluorescent material may be used instead of the phosphorescent material. The thermally activated delayed fluorescent material is a material that has a small difference between the triplet excitation energy level and the singlet excitation energy level, and has a function of converting energy from the triplet excited state to the singlet excited state by reverse intersystem crossing. Therefore, the triplet excited state can be upconverted to the singlet excited state by a small amount of thermal energy (reverse intersystem crossing), and light emission (fluorescence) from the singlet excited state can be efficiently exhibited. In addition, as a condition for efficiently obtaining thermally activated delayed fluorescence, the energy difference between the triplet excitation energy level and the singlet excitation energy level is preferably more than 0 eV and 0.2 eV or less, more preferably more than 0 eV and 0.1 eV or less.

[0125] The guest material 119 (phosphorescent compound) may be an iridium, rhodium, or platinum-based organometallic complex or metal complex, and among these, a platinum complex is preferred as the metal complex. Other examples include a platinum complex having a nitrogen-containing heterocyclic carbene. Organic iridium complexes, such as iridium orthometal complexes, may also be used. Examples of the ligand to be orthometalated include 4H-triazole ligands, 1H-triazole ligands, imidazole ligands, pyridine ligands, pyrimidine ligands, pyrazine ligands, and isoquinoline ligands.

[0126] In addition, it is preferable to select the organic compound 118_1, the organic compound 118_2, and the guest material 119 (phosphorescent compound) so that the guest material 119 (phosphorescent compound) has a LUMO level higher than the LUMO level of the organic compound 118_1 and a HOMO level lower than the HOMO level of the organic compound 118_2. This makes it possible to provide a light-emitting device with high luminous efficiency that can be driven at a low voltage.

[0127] In addition, it is preferable to select the organic compound 118_1, the organic compound 118_2, and the guest material 119 (phosphorescent compound) so that the guest material 119 (phosphorescent compound) has a LUMO level higher than the LUMO level of the organic compound 118_1 and a HOMO level higher than the HOMO level of the organic compound 118_2. This makes it possible to provide a light-emitting device with high luminous efficiency that can be driven at a low voltage.

[0128] In addition, it is preferable to select the organic compound 118_1 and the guest material 119 (phosphorescent compound) so that the energy difference between the LUMO level of the organic compound 118_1 and the HOMO level of the guest material 119 (phosphorescent compound) is equal to or greater than the energy calculated from the absorption edge located at the longest wavelength among the absorption edges in the absorption spectrum of the guest material 119 (phosphorescent compound). This makes it possible to obtain a light-emitting device with high luminous efficiency that can be driven at a low voltage.

[0129] The absorption edge located at the longest wavelength in the absorption spectrum can be obtained by measuring the absorption spectrum of the target substance in a thin film state or in a thin film obtained by doping the target substance into a matrix material, and then obtaining the absorption edge from a Tauc plot assuming direct transition. Alternatively, the absorption spectrum of a solution can be measured, a tangent line can be drawn at the half-value on the longest wavelength side of the peak or shoulder peak observed at the longest wavelength of the absorption spectrum, and the absorption edge can be calculated from the intersection of the tangent line with the horizontal axis (wavelength) or the baseline. There are no particular limitations on the solvent for the solution, but solvents with relatively low polarity, such as toluene and chloroform, are preferred.

[0130] The values ​​of the HOMO level and the LUMO level used in this specification can be determined by electrochemical measurements. Representative examples of electrochemical measurements include cyclic voltammetry (CV) measurements and differential pulse voltammetry (DPV) measurements.

[0131] In cyclic voltammetry (CV) measurements, the HOMO and LUMO levels (E) are determined by measuring the oxidation peak potential (E pa ), and reduction peak potential (E pc In the measurement, the HOMO level is obtained from potential scanning in the positive direction, and the LUMO level is obtained from potential scanning in the negative direction. The scan speed in the measurement is 0.1 V / s.

[0132] The specific procedure for calculating the HOMO and LUMO levels is described below. The oxidation peak potential (E pa ), and reduction peak potential (E pc ) to obtain the standard redox potential (E o )(=(E pa +E pc ) / 2) and calculate the potential energy (E x ) to obtain the values ​​of the HOMO and LUMO levels (E) (=E x -E o ) can be calculated respectively.

[0133] The above shows the case where a reversible redox wave is obtained. However, when an irreversible redox wave is obtained, the oxidation peak potential (E pa The reduction peak potential (E pc ) and the standard redox potential (E o ) to one decimal place. In addition, the reduction peak potential (E pc ) plus a certain value (0.1 eV) is taken as the oxidation peak potential (E pa ) and the standard redox potential (Eo ) to one decimal place.

[0134] Examples of substances having an emission peak in the blue or green wavelength region include tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN2]phenyl-κC}iridium(III) (abbreviation: Ir(mpptz-dmp)3), tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazolato)iridium(III) (abbreviation: Ir(Mptz )3), tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: Ir(iPrptz-3b)3), tris[3-(5-biphenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: Ir(iPr5btz)3), and other organometallic iridium complexes having a 4H-triazole skeleton, such as tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: Ir(iPr5btz)3), Organometallic iridium complexes with 1H-triazole skeletons such as tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: Ir(Mptz1-mp)3) and tris(1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato)iridium(III) (abbreviation: Ir(Prptz1-Me)3), fac-tris[1-(2,6-diphenyl organometallic iridium complexes with an imidazole skeleton, such as tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: Ir(iPrpim)3), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: Ir(dmpimpt-Me)3), and bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ]iridium(III) tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ]iridium(III) picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinato-N,C2’}Iridium(III) picolinate (abbreviation: Ir(CF3ppy)2(pic)), bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ] Organometallic iridium complexes having a phenylpyridine derivative having an electron-withdrawing group as a ligand, such as iridium(III) acetylacetonate (abbreviation: FIr(acac)). Among the above, organometallic iridium complexes having a nitrogen-containing five-membered heterocyclic skeleton, such as a 4H-triazole skeleton, a 1H-triazole skeleton, and an imidazole skeleton, are particularly preferred because they have high triplet excitation energy and are excellent in reliability or luminous efficiency.

[0135] Examples of substances having an emission peak in the green or yellow wavelength region include tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: Ir(mppm)3), tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: Ir(tBuppm)3), (acetylacetonato)bis(6-methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: Ir(mppm)2(acac)). , (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium(III) (abbreviation: Ir(tBuppm)2(acac)), (acetylacetonato)bis[4-(2-norbornyl)-6-phenylpyrimidinato]iridium(III) (abbreviation: Ir(nbppm)2(acac)), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenylpyrimidinato]iridium(III ) (abbreviation: Ir(mpmppm)2(acac)), (acetylacetonato)bis{4,6-dimethyl-2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN3]phenyl-κC}iridium(III) (abbreviation: Ir(dmppm-dmp)2(acac)), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: Ir(dppm)2(acac)) organometallic iridium complexes, organometallic iridium complexes with a pyrazine skeleton such as (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazinate)iridium(III) (abbreviation: Ir(mppr-Me)2(acac)) and (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinate)iridium(III) (abbreviation: Ir(mppr-iPr)2(acac)); 2’ ) Iridium(III) (abbreviation: Ir(ppy)3), bis(2-phenylpyridinato-N,C 2’)iridium(III) acetylacetonate (abbreviation: Ir(ppy)2(acac)), bis(benzo[h]quinolinato)iridium(III) acetylacetonate (abbreviation: Ir(bzq)2(acac)), tris(benzo[h]quinolinato)iridium(III) (abbreviation: Ir(bzq)3), tris(2-phenylquinolinato-N,C 2’ ) Iridium(III) (abbreviation: Ir(pq)3), bis(2-phenylquinolinato-N,C 2’ Organometallic iridium complexes with pyridine skeletons such as iridium(III) acetylacetonate (abbreviation: Ir(pq)2(acac)), bis(2,4-diphenyl-1,3-oxazolato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: Ir(dpo)2(acac)), bis{2-[4'-(perfluorophenyl)phenyl]pyridinato-N,C 2’}Iridium(III) acetylacetonate (abbreviation: Ir(p-PF-ph)2(acac)), bis(2-phenylbenzothiazolato-N,C 2’ Examples include organometallic iridium complexes such as iridium(III) acetylacetonate (abbreviation: Ir(bt)2(acac)), and rare earth metal complexes such as tris(acetylacetonate)(monophenanthroline)terbium(III) (abbreviation: Tb(acac)3(Phen)). Among the above, organometallic iridium complexes having a pyrimidine skeleton are particularly preferred because of their outstanding reliability and luminous efficiency.

[0136] Examples of substances having an emission peak in the yellow or red wavelength region include pyrimidine skeletons such as (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(III) (abbreviation: Ir(5mdppm)2(dibm)), bis[4,6-bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: Ir(5mdppm)2(dpm)), and bis[4,6-di(naphthalen-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: Ir(d1npm)2(dpm)). organometallic iridium complexes with a pyrazine skeleton, such as (acetylacetonato)bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviation: Ir(tppr)2(acac)), bis(2,3,5-triphenylpyrazinato)(dipivaloylmethanato)iridium(III) (abbreviation: Ir(tppr)2(dpm)), and (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: Ir(Fdpq)2(acac)); 2’ ) Iridium(III) (abbreviation: Ir(piq)3), bis(1-phenylisoquinolinato-N,C 2’ In addition to organometallic iridium complexes having a pyridine skeleton such as iridium(III) acetylacetonate (abbreviation: Ir(piq)2(acac)), platinum complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: PtOEP), and rare earth metal complexes such as tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: Eu(DBM)3(Phen)) and tris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviation: Eu(TTA)3(Phen)). Among the above, organometallic iridium complexes having a pyrimidine skeleton are particularly preferred because they are remarkably excellent in reliability or luminous efficiency. Furthermore, an organometallic iridium complex having a pyrazine skeleton can emit red light with good chromaticity.

[0137] The light-emitting material contained in the light-emitting layer 113 may be any material capable of converting triplet excitation energy into light emission. In addition to phosphorescent compounds, materials capable of converting triplet excitation energy into light emission include thermally activated delayed fluorescence (TADF) materials. Therefore, the term "phosphorescent compound" may be read as "thermally activated delayed fluorescence material." Note that the thermally activated delayed fluorescence material is a material that has a small difference between the triplet excitation energy level and the singlet excitation energy level and has a function of converting energy from the triplet excited state to the singlet excited state by reverse intersystem crossing. Therefore, the triplet excited state can be upconverted (reverse intersystem crossing) to the singlet excited state by a small amount of thermal energy, and light emission (fluorescence) from the singlet excited state can be efficiently exhibited. In addition, the condition for efficiently obtaining thermally activated delayed fluorescence is that the energy difference between the triplet excitation energy level and the singlet excitation energy level is preferably greater than 0 eV and less than 0.2 eV, and more preferably greater than 0 eV and less than 0.1 eV.

[0138] When the thermally activated delayed fluorescent material is composed of one type of material, for example, the following material can be used.

[0139] First, there are derivatives of fullerene, acridine derivatives such as proflavine, eosin, etc. Also, there are metal-containing porphyrins including magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), palladium (Pd), etc. Examples of the metal-containing porphyrin include protoporphyrin-tin fluoride complex (SnF2(Proto IX)), mesoporphyrin-tin fluoride complex (SnF2(Meso IX)), hematoporphyrin-tin fluoride complex (SnF2(Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (SnF2(Copro III-4Me)), octaethylporphyrin-tin fluoride complex (SnF2(OEP)), etioporphyrin-tin fluoride complex (SnF2(Etio I)), and octaethylporphyrin-platinum chloride complex (PtCl2(OEP)).

[0140] In addition, as the thermally activated delayed fluorescent material composed of one kind of material, a heterocyclic compound having a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring can also be used. Specifically, 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 2-[4-(10H-phenoxazin-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4- (5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthen-9-one (abbreviation: ACRXTN), bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridin-9,9'-anthracene]-10'-one (abbreviation: ACRSA), etc. The heterocyclic compound has a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring, and therefore has high electron transport properties and hole transport properties, making it preferable. Among the skeletons having a π-electron-deficient heteroaromatic ring, a diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton) or a triazine skeleton is preferred because it is stable and reliable. In addition, among the skeletons having a π-electron-rich heteroaromatic ring, an acridine skeleton, a phenoxazine skeleton, a thiophene skeleton, a furan skeleton, and a pyrrole skeleton are stable and reliable, so it is preferred to have one or more selected from these skeletons. Note that, as the pyrrole skeleton, an indole skeleton, a carbazole skeleton, and a 3-(9-phenyl-9H-carbazol-3-yl)-9H-carbazole skeleton are particularly preferred.In addition, a substance in which a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring are directly bonded to each other is particularly preferable because the π-electron-rich heteroaromatic ring has a strong donor property and the π-electron-deficient heteroaromatic ring has a strong acceptor property, and the difference between the singlet excitation energy level and the triplet excitation energy level is small.

[0141] The light-emitting layer 113 may be formed of two or more layers. For example, when the first light-emitting layer and the second light-emitting layer are laminated in order from the hole-transporting layer side to form the light-emitting layer 113, a substance having a hole-transporting property may be used as a host material of the first light-emitting layer, and a substance having an electron-transporting property may be used as a host material of the second light-emitting layer. The light-emitting materials of the first light-emitting layer and the second light-emitting layer may be the same or different, and may be materials having a function of emitting light of the same color or materials having a function of emitting light of different colors. By using light-emitting materials having a function of emitting light of different colors for the two light-emitting layers, respectively, a plurality of lights can be simultaneously obtained. In particular, it is preferable to select a light-emitting material for each light-emitting layer so that the light emitted by the two light-emitting layers becomes white.

[0142] The light-emitting layer 113 may contain a material other than the host material 118 and the guest material 119 .

[0143] The light-emitting layer 113 can be formed by a deposition method (including a vacuum deposition method), an inkjet method, a coating method, a gravure printing method, etc. In addition to the above-mentioned materials, the light-emitting layer 113 may contain an inorganic compound such as a quantum dot or a polymer compound (oligomer, dendrimer, polymer, etc.).

[0144] <Hole injection layer> The hole injection layer (111, 111a, 111b) is a layer that injects holes from the first electrode 101, which is an anode, and the charge generation layer (106, 106a, 106b) to the organic compound layer (103, 103a, 103b), and is a layer that contains an organic acceptor material and a material with high hole injection properties.

[0145] The hole injection layer (111, 111a, 111b) has a function of promoting hole injection by reducing the hole injection barrier from one of the pair of electrodes (the first electrode 101 or the second electrode 102), and is formed of, for example, a transition metal oxide, a phthalocyanine derivative, or an aromatic amine. Examples of the transition metal oxide include molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, and manganese oxide. Examples of the phthalocyanine derivative include phthalocyanine and metal phthalocyanine. Examples of the aromatic amine include benzidine derivatives and phenylenediamine derivatives. Polymer compounds such as polythiophene and polyaniline can also be used, and a representative example is poly(ethylenedioxythiophene) / polystyrenesulfonic acid, which is a self-doped polythiophene.

[0146] The hole injection layer (111, 111a, 111b) may be a layer having a composite material of a hole transporting material and a material exhibiting electron accepting properties. Alternatively, a laminate of a layer containing a material exhibiting electron accepting properties and a layer containing a hole transporting material may be used. Charges can be transferred between these materials in a stationary state or in the presence of an electric field. Examples of materials exhibiting electron accepting properties include organic acceptors such as quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene derivatives. Specifically, the materials include compounds having an electron withdrawing group (halogen group or cyano group), such as 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, and 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN). In addition, transition metal oxides, for example, oxides of metals in Groups 4 to 8, can be used. Specific examples include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide. Among these, molybdenum oxide is preferred because it is stable in the air, has low hygroscopicity, and is easy to handle.

[0147] As the hole transporting material, a material having a higher hole transporting property than that of electrons can be used. -6 cm 2 It is preferable that the material has a hole mobility of 100 / Vs or more. Specifically, aromatic amines, carbazole derivatives, aromatic hydrocarbons, stilbene derivatives, and the like, which are listed as hole-transporting materials that can be used for the light-emitting layer 113, can be used. The hole-transporting material may be a polymer compound.

[0148] <Hole transport layer> The hole transport layer (112, 112a, 112b) is a layer containing a hole transport material, and the hole transport material exemplified as the material of the hole injection layer (111, 111a, 111b) can be used. Since the hole transport layer (112, 112a, 112b) has a function of transporting holes injected into the hole injection layer (111, 111a, 111b) to the light emitting layer (113, 113a, 113b), it is preferable that the hole transport layer (112, 112a, 112b) has a HOMO level that is the same as or close to the HOMO level of the hole injection layer (111, 111a, 111b).

[0149] The hole transport material is 1×10 -6 cm 2 It is preferable that the material has a hole mobility of 1 / Vs or more. However, other materials may be used as long as they have a higher hole transporting property than electron transporting property. Note that the layer containing the material having a high hole transporting property may be a single layer or a stack of two or more layers made of the above-mentioned materials.

[0150] ≪Electron transport layer≫ The electron transport layer (114, 114a, 114b) has a function of transporting electrons injected from the other of the pair of electrodes (the first electrode 101 or the second electrode 102) through the electron injection layer (115, 115a, 115b) to the light-emitting layer 113. As the electron transport material, a material having a higher electron transporting property than a hole transporting property can be used, and the electron transporting property is preferably 1×10 -6 cm 2It is preferable that the material has an electron mobility of 1×10 / Vs or more. As a compound that easily receives electrons (a material having electron transport properties), a compound having a π-electron-deficient heteroaromatic ring skeleton such as a nitrogen-containing heteroaromatic compound, or a metal complex can be used. Specific examples of the electron transport material that can be used in the light-emitting layer 113 include metal complexes having a quinoline ligand, a benzoquinoline ligand, an oxazole ligand, or a thiazole ligand. Other examples include oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, phenanthroline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and triazine derivatives. The electron transport material has a molecular weight of 1×10 -6 cm 2 It is preferable that the electron transport layer is a material having an electron mobility of 1 / Vs or more. Note that any material other than the above may be used as the electron transport layer as long as it has a higher electron transporting property than a hole transporting property. The electron transport layer (114, 114a, 114b) may be a single layer or a stack of two or more layers made of the above materials.

[0151] In addition, a layer for controlling the movement of electron carriers may be provided between the electron transport layer (114, 114a, 114b) and the light-emitting layer (113, 113a, 113b). This layer is made by adding a small amount of a substance with high electron trapping properties to a material with high electron transport properties as described above, and it is possible to adjust the carrier balance by suppressing the movement of electron carriers. This type of configuration is very effective in suppressing problems (e.g., a decrease in device life) caused by electrons penetrating the light-emitting layer.

[0152] ≪Electron injection layer≫ The electron injection layer (115, 115a, 115b) has a function of promoting electron injection by reducing the barrier for electron injection from the second electrode 102, and may be made of, for example, a Group 1 metal, a Group 2 metal, or an oxide, halide, or carbonate thereof. A composite material of the above-mentioned electron transport material and a material that exhibits electron donating properties thereto may also be used. Examples of materials that exhibit electron donating properties include Group 1 metals, Group 2 metals, or oxides thereof. Specific examples include lithium fluoride (LiF), sodium fluoride (NaF), cesium fluoride (CsF), calcium fluoride (CaF2), lithium oxide (LiO x ) or an alkaline earth metal, or a compound thereof, can be used. Also, a rare earth metal compound, such as erbium fluoride (ErF3), can be used. Also, an electride can be used for the electron injection layer 115. For example, the electride can be a substance in which a high concentration of electrons is added to a mixed oxide of calcium and aluminum. Also, a substance that can be used for the electron transport layer (114, 114a, 114b) can be used for the electron injection layer (115, 115a, 115b).

[0153] In addition, a composite material obtained by mixing an organic compound and an electron donor (donor) may be used for the electron injection layer (115, 115a, 115b). Such a composite material has excellent electron injection and transport properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material that is excellent in transporting the generated electrons, and specifically, for example, the above-mentioned substance constituting the electron transport layer 114 (metal complex, heteroaromatic compound, etc.) can be used. The electron donor may be any substance that exhibits electron donating properties to the organic compound. Specifically, alkali metals, alkaline earth metals, or rare earth metals are preferred, and examples of the substance include lithium, sodium, cesium, magnesium, calcium, erbium, and ytterbium. In addition, alkali metal oxides or alkaline earth metal oxides are preferred, and examples of the substance include lithium oxide, calcium oxide, and barium oxide. In addition, a Lewis base such as magnesium oxide can also be used. In addition, an organic compound such as tetrathiafulvalene (abbreviation: TTF) can also be used.

[0154] The above-mentioned light-emitting layer, hole injection layer, hole transport layer, electron transport layer, and electron injection layer can be formed by a method such as a vapor deposition method (including a vacuum vapor deposition method), an inkjet method, a coating method, gravure printing, etc. In addition to the above-mentioned materials, the above-mentioned light-emitting layer, hole injection layer, hole transport layer, electron transport layer, and electron injection layer may be made of an inorganic compound such as a quantum dot or a polymer compound (oligomer, dendrimer, polymer, etc.).

[0155] As the quantum dots, colloidal quantum dots, alloy quantum dots, core-shell quantum dots, core quantum dots, etc. may be used. Quantum dots containing element groups of groups 2 and 16, 13 and 15, 13 and 17, 11 and 17, or 14 and 15 may be used. Quantum dots containing elements such as cadmium (Cd), selenium (Se), zinc (Zn), sulfur (S), phosphorus (P), indium (In), tellurium (Te), lead (Pb), gallium (Ga), arsenic (As), and aluminum (Al) may be used.

[0156] The first electrode 101 and the second electrode 102 function as an anode or a cathode of a light-emitting device. The first electrode 101 and the second electrode 102 can be formed using a metal, an alloy, a conductive compound, or a mixture or laminate thereof.

[0157] It is preferable that one of the first electrode 101 and the second electrode 102 is made of a conductive material having a function of reflecting light. Examples of the conductive material include aluminum (Al) and alloys containing Al. Examples of alloys containing Al include alloys containing Al and L (L represents one or more of titanium (Ti), neodymium (Nd), nickel (Ni), and lanthanum (La)), such as alloys containing Al and Ti, or alloys containing Al, Ni, and La. Aluminum has a low resistance value and a high light reflectance. In addition, aluminum is abundant in the earth's crust and is inexpensive, so that the manufacturing cost of the light-emitting device can be reduced by using aluminum. In addition, an alloy containing silver (Ag) or Ag and N (N represents one or more of yttrium (Y), Nd, magnesium (Mg), ytterbium (Yb), Al, Ti, gallium (Ga), zinc (Zn), indium (In), tungsten (W), manganese (Mn), tin (Sn), iron (Fe), Ni, copper (Cu), palladium (Pd), iridium (Ir), or gold (Au)) may be used. Examples of the alloy containing silver include an alloy containing silver, palladium, and copper, an alloy containing silver and copper, an alloy containing silver and magnesium, an alloy containing silver and nickel, an alloy containing silver and gold, and an alloy containing silver and ytterbium. In addition, transition metals such as tungsten, chromium (Cr), molybdenum (Mo), copper, and titanium can be used.

[0158] Furthermore, light emitted from the light-emitting layer is extracted through one or both of the first electrode 101 and the second electrode 102. Therefore, at least one of the first electrode 101 and the second electrode 102 is preferably formed from a conductive material having a light transmitting function. The conductive material has a visible light transmittance of 40% or more and 100% or less, preferably 60% or more and 100% or less, and a resistivity of 1×10 -2 Examples include conductive materials with a resistance of Ω·cm or less.

[0159] The first electrode 101 and the second electrode 102 may be formed of a conductive material having a function of transmitting and reflecting light. The conductive material has a visible light reflectance of 20% to 80%, preferably 40% to 70%, and a resistivity of 1×10 -2 Examples of the conductive material include a material having a resistivity of Ω·cm or less. For example, the conductive material can be formed by using one or more conductive metals, alloys, conductive compounds, etc. Specifically, for example, metal oxides such as indium tin oxide (hereinafter, ITO), indium tin oxide containing silicon or silicon oxide (abbreviated as ITSO), indium oxide-zinc oxide, indium oxide-tin oxide containing titanium, indium-titanium oxide, indium oxide containing tungsten oxide and zinc oxide, etc. can be used. In addition, a metal thin film having a thickness of about 1 nm or more and 30 nm or less that transmits light can be used. As the metal, for example, Ag, or an alloy such as Ag and Al, Ag and Mg, Ag and Au, Ag and Yb, etc. can be used.

[0160] In this specification and the like, the material having a function of transmitting light may be any material that has a function of transmitting visible light and has electrical conductivity, and includes, for example, oxide conductors such as ITO as described above, as well as oxide semiconductors and organic conductors containing organic substances. Examples of organic conductors containing organic substances include composite materials obtained by mixing an organic compound with an electron donor, and composite materials obtained by mixing an organic compound with an electron acceptor. Inorganic carbon-based materials such as graphene may also be used. The resistivity of the material is preferably 1×10 5 Ω cm or less, more preferably 1×10 4 Ω·cm or less.

[0161] Alternatively, one or both of the first electrode 101 and the second electrode 102 may be formed by stacking a plurality of the above materials.

[0162] In addition, in order to improve the light extraction efficiency, a material having a higher refractive index than an electrode having a function of transmitting light may be formed in contact with the electrode. Such a material may be a material having a function of transmitting visible light, and may be a material having or not having electrical conductivity. For example, in addition to the oxide conductor as described above, an oxide semiconductor and an organic material may be mentioned. As the organic material, for example, the materials exemplified in the light-emitting layer, the hole injection layer, the hole transport layer, the electron transport layer, or the electron injection layer may be mentioned. In addition, an inorganic carbon-based material or a metal thin film having a thickness of several nm to several tens of nm may be used, and a plurality of layers may be stacked.

[0163] When the first electrode 101 or the second electrode 102 functions as a cathode, it is preferable that the electrode has a material with a small work function (3.8 eV or less). For example, elements belonging to Group 1 or Group 2 of the periodic table (alkali metals such as lithium, sodium, and cesium, alkaline earth metals such as calcium and strontium, magnesium, etc.), alloys containing these elements (for example, Ag and Mg, Al and Li), rare earth metals such as europium (Eu) and Yb, alloys containing these rare earth metals, alloys containing aluminum and silver, etc. can be used.

[0164] When the first electrode 101 or the second electrode 102 is used as an anode, it is preferable to use a material having a large work function (4.0 eV or more).

[0165] The first electrode 101 and the second electrode 102 may be a laminate of a conductive material having a light reflecting function and a conductive material having a light transmitting function. In that case, the first electrode 101 and the second electrode 102 are preferable because they can have a function of adjusting the optical path so that light of a desired wavelength from each light emitting layer can be resonated and the light of the desired wavelength can be intensified.

[0166] The first electrode 101 and the second electrode 102 can be formed by any suitable method, such as sputtering, vapor deposition, printing, coating, MBE (Molecular Beam Epitaxy), CVD, pulsed laser deposition, or ALD (Atomic Layer Deposition).

[0167] <Charge generation layer> The charge generation layer 106 has a function of injecting electrons into the organic compound layer 103a and injecting holes into the organic compound layer 103b when a voltage is applied between the first electrode (anode) 101 and the second electrode (cathode) 102. The charge generation layer 106 may be a structure in which an electron acceptor is added to a hole transporting material (also called a P-type layer), or a structure in which an electron donor is added to an electron transporting material (also called an electron injection buffer layer). In addition, both of these structures may be stacked. Furthermore, an electron relay layer may be provided between the P-type layer and the electron injection buffer layer. By forming the charge generation layer 106 using the above-mentioned material, it is possible to suppress an increase in driving voltage when organic compound layers are stacked.

[0168] In the case where the charge generation layer 106 has a structure (P-type layer) in which an electron acceptor is added to a hole transporting material that is an organic compound, the material shown in this embodiment mode can be used as the hole transporting material. Examples of the electron acceptor include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ) and chloranil. Examples of the oxide of a metal that belongs to Groups 4 to 8 of the periodic table can also be used. Specific examples of the oxide include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide. Note that the above-mentioned acceptor material may also be used. In addition, a mixed film obtained by mixing materials constituting the P-type layer may be used, or single films containing each material may be stacked.

[0169] In the charge generation layer 106, when an electron donor is added to an electron transporting material (electron injection buffer layer), the material shown in this embodiment can be used as the electron transporting material. In addition, an alkali metal, an alkaline earth metal, a rare earth metal, or a metal belonging to Group 2 or Group 13 in the periodic table, and an oxide or carbonate thereof can be used as the electron donor. Specifically, it is preferable to use lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide (Li2O), cesium carbonate, or the like. In addition, an organic compound such as tetrathianaphthacene may be used as the electron donor.

[0170] In the case where an electron relay layer is provided between the P-type layer and the electron injection buffer layer in the charge generation layer 106, the electron relay layer contains at least a substance having electron transport properties, and has a function of preventing interaction between the electron injection buffer layer and the P-type layer and smoothly transferring electrons. The LUMO level of the substance having electron transport properties contained in the electron relay layer is preferably between the LUMO level of the acceptor substance in the P-type layer and the LUMO level of the substance having electron transport properties contained in the electron transport layer in contact with the charge generation layer 106. The specific energy level of the LUMO level of the substance having electron transport properties used in the electron relay layer is -5.0 eV or more, preferably -5.0 eV or more and -3.0 eV or less. Note that, as the substance having electron transport properties used in the electron relay layer, a phthalocyanine-based material or a metal complex having a metal-oxygen bond and an aromatic ligand is preferably used.

[0171] Although FIG. 2D shows a structure in which the organic compound layer 103 has two stacked layers, a stacked structure of three or more organic compound layers may be used by providing a charge generating layer between different organic compound layers.

[0172] <Cap layer> Although not shown in FIGS. 2A to 2E, a capping layer may be provided on the second electrode 102 of the light-emitting device. For example, a material with a high refractive index can be used for the capping layer. By providing the capping layer on the second electrode 102, the extraction efficiency of light emitted from the second electrode 102 can be improved.

[0173] Specific examples of materials that can be used for the cap layer include 5,5'-diphenyl-2,2'-di-5H-[1]benzothieno[3,2-c]carbazole (abbreviation: BisBTc), 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), and the like. In addition, the organic compounds described in the first embodiment can be used.

[0174] <Substrate> The light-emitting device according to one embodiment of the present invention may be fabricated over a substrate made of glass, plastic, etc. The order of fabrication on the substrate may be from the first electrode 101 side or from the second electrode 102 side.

[0175] As a substrate on which a light-emitting device according to one embodiment of the present invention can be formed, for example, glass, quartz, or plastic can be used. A flexible substrate can also be used. A flexible substrate is a substrate that can be bent (flexible), and examples of the flexible substrate include a plastic substrate made of polycarbonate or polyarylate. A film, an inorganic deposition film, or the like can also be used. Any other substrate may be used as long as it functions as a support in the manufacturing process of the light-emitting device and the optical element. Alternatively, any substrate having a function of protecting the light-emitting device and the optical element may be used.

[0176] For example, in the present specification, a light-emitting device can be formed using various substrates. The type of substrate is not particularly limited. Examples of the substrate include a semiconductor substrate (e.g., a single crystal substrate or a silicon substrate), an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a metal substrate, a stainless steel substrate, a substrate having a stainless steel foil, a tungsten substrate, a substrate having a tungsten foil, a flexible substrate, a laminated film, cellulose nanofiber (CNF) containing a fibrous material, paper, or a base film. Examples of glass substrates include barium borosilicate glass, aluminoborosilicate glass, or soda lime glass. Examples of flexible substrates, laminated films, base films, and the like include the following. For example, there are plastics represented by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), and polytetrafluoroethylene (PTFE). Alternatively, there is an acrylic resin, or the like. Alternatively, there are polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride, or the like. Alternatively, examples include resins such as polyamide resin, polyimide resin, aramid resin, and epoxy resin, inorganic vapor deposition films, and papers.

[0177] Alternatively, a flexible substrate may be used as the substrate, and the light-emitting device may be formed directly on the flexible substrate. Alternatively, a release layer may be provided between the substrate and the light-emitting device. The release layer can be used to separate the light-emitting device from the substrate after a part or all of the light-emitting device is completed thereon, and to transfer the device to another substrate. In this case, the light-emitting device can be transferred to a substrate having poor heat resistance or a flexible substrate. The release layer may be, for example, a laminated structure of inorganic films of a tungsten film and a silicon oxide film, or a structure in which a resin film such as polyimide is formed on a substrate.

[0178] That is, a light-emitting device may be formed using a certain substrate, and then the light-emitting device may be transferred to another substrate, and the light-emitting device may be disposed on the other substrate. In addition to the above-mentioned substrates, examples of the substrate onto which the light-emitting device may be transferred include a cellophane substrate, a stone substrate, a wood substrate, a cloth substrate (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester), or regenerated fibers (acetate, cupra, rayon, regenerated polyester), etc.), a leather substrate, or a rubber substrate. By using these substrates, a light-emitting device that is not easily broken, has high heat resistance, is lightweight, or is thin.

[0179] In addition, for example, a field effect transistor (FET) may be formed on the above-mentioned substrate, and a light-emitting device may be fabricated on an electrode electrically connected to the FET, thereby fabricating an active matrix display device in which the FET controls the driving of the light-emitting device.

[0180] Note that one embodiment of the present invention has been described in this embodiment. Alternatively, one embodiment of the present invention will be described in another embodiment. However, one embodiment of the present invention is not limited to these. That is, since various embodiments of the present invention are described in this embodiment and other embodiments, one embodiment of the present invention is not limited to a specific embodiment. For example, although an example of the application to a light-emitting device has been described as one embodiment of the present invention, one embodiment of the present invention is not limited to this. For example, depending on the circumstances or the situation, one embodiment of the present invention may not be applied to a light-emitting device. Alternatively, for example, one embodiment of the present invention has a first organic compound, a second organic compound, and a guest material having a function of converting triplet excitation energy into light emission, and the LUMO level of the first organic compound is lower than the LUMO level of the second organic compound, and the HOMO level of the first organic compound is lower than the HOMO level of the second organic compound, but one embodiment of the present invention is not limited to this. Depending on the circumstances or the situation, one embodiment of the present invention may not have a LUMO level of the first organic compound lower than the LUMO level of the second organic compound, for example. Alternatively, the HOMO level of the first organic compound may not be lower than the HOMO level of the second organic compound. Alternatively, for example, in one embodiment of the present invention, an example in which the first organic compound and the second organic compound form an exciplex has been shown, but one embodiment of the present invention is not limited thereto. Depending on the circumstances, or depending on the situation, in one embodiment of the present invention, for example, the first organic compound and the second organic compound may not form an exciplex. Alternatively, for example, in one embodiment of the present invention, an example in which the LUMO level of the guest material is higher than the LUMO level of the first organic compound and the HOMO level of the guest material is lower than the HOMO level of the second organic compound has been shown, but one embodiment of the present invention is not limited thereto. Depending on the circumstances, or depending on the situation, in one embodiment of the present invention, for example, the LUMO level of the guest material may not be higher than the LUMO level of the first organic compound. Alternatively, the HOMO level of the guest material may not be lower than the HOMO level of the second organic compound.

[0181] The structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiments.

[0182] (Embodiment 3) 3A and 3B, a light-emitting device is constituted by forming a plurality of the light-emitting devices described in the above embodiment over an insulating layer 175. In this embodiment, a light-emitting device according to one embodiment of the present invention will be described in detail.

[0183] The light emitting device 1000 has a pixel section 177 in which a plurality of pixels 178 are arranged in a matrix. The pixel 178 has a sub-pixel 110R, a sub-pixel 110G, and a sub-pixel 110B.

[0184] In this specification and the like, for example, matters common to the subpixels 110R, 110G, and 110B may be described as subpixel 110. Furthermore, for components distinguished by alphabets, matters common to the corresponding structures may be described using symbols without the alphabets.

[0185] The sub-pixel 110R emits red light, the sub-pixel 110G emits green light, and the sub-pixel 110B emits blue light. This allows an image to be displayed in the pixel section 177. In the present embodiment, sub-pixels of three colors, red (R), green (G), and blue (B), are described as an example, but the present invention is not limited to this configuration. That is, combinations of sub-pixels of other colors may be used. For example, the number of sub-pixels is not limited to three, and may be four or more. Examples of the four sub-pixels include sub-pixels of four colors, R, G, B, and white (W), sub-pixels of four colors, R, G, B, and yellow (Y), and sub-pixels of R, G, B, and infrared light (IR).

[0186] In this specification and the like, the row direction may be referred to as the X direction, and the column direction may be referred to as the Y direction. The X direction and the Y direction intersect, for example, perpendicularly.

[0187] 3A shows an example in which subpixels of different colors are arranged side by side in the X direction, and subpixels of the same color are arranged side by side in the Y direction. Note that subpixels of different colors may be arranged side by side in the Y direction, and subpixels of the same color may be arranged side by side in the X direction.

[0188] A connection portion 140 and a region 141 may be provided outside the pixel portion 177. For example, the region 141 may be provided between the pixel portion 177 and the connection portion 140. The region 141 is provided with an organic compound layer 103. In addition, the connection portion 140 is provided with a conductive layer 151C.

[0189] 3A shows an example in which the region 141 and the connection portion 140 are located on the right side of the pixel portion 177, but the positions of the region 141 and the connection portion 140 are not particularly limited. The region 141 and the connection portion 140 may be singular or plural.

[0190] Fig. 3(B) is an example of a cross-sectional view between dashed line A1-A2 in Fig. 3(A). As shown in Fig. 3(B), the light-emitting device 1000 has an insulating layer 171, a conductive layer 172 on the insulating layer 171, an insulating layer 173 on the insulating layer 171 and on the conductive layer 172, an insulating layer 174 on the insulating layer 173, and an insulating layer 175 on the insulating layer 174. The insulating layer 171 may be provided on a substrate (not shown). An opening reaching the conductive layer 172 is provided in the insulating layer 175, the insulating layer 174, and the insulating layer 173, and a plug 176 is provided to fill the opening.

[0191] In the pixel section 177, the light emitting device 130 is provided on the insulating layer 175 and the plug 176. A protective layer 131 is provided so as to cover the light emitting device 130. The substrate 120 is bonded onto the protective layer 131 by a resin layer 122. An inorganic insulating layer 125 and an insulating layer 127 on the inorganic insulating layer 125 may be provided between adjacent light emitting devices 130.

[0192] 3B shows multiple cross sections of the inorganic insulating layer 125 and the insulating layer 127, it is preferable that the inorganic insulating layer 125 and the insulating layer 127 are connected to one another when the light-emitting device 1000 is viewed from above. In other words, it is preferable that the inorganic insulating layer 125 and the insulating layer 127 are insulating layers having openings over the first electrodes.

[0193] In FIG. 3B, the light emitting device 130 includes a light emitting device 130R, a light emitting device 130G, and a light emitting device 130B. The light emitting device 130R, the light emitting device 130G, and the light emitting device 130B emit light of different colors. For example, the light emitting device 130R can emit red light, the light emitting device 130G can emit green light, and the light emitting device 130B can emit blue light. The light emitting device 130R, the light emitting device 130G, or the light emitting device 130B may emit other visible light or infrared light.

[0194] The organic compound layer 103 has at least a light-emitting layer, and may have other functional layers (such as a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer, an electron transport layer, and an electron injection layer). The organic compound layer 103 and the common layer 104 may be combined to form a functional layer (such as a hole injection layer, a hole transport layer, a hole blocking layer, a light-emitting layer, an electron blocking layer, an electron transport layer, and an electron injection layer) included in the light-emitting device.

[0195] The light-emitting device of one embodiment of the present invention can be, for example, a top-emission type that emits light in a direction opposite to a substrate on which the light-emitting device is formed. Note that the light-emitting device of one embodiment of the present invention may be a bottom-emission type.

[0196] The light-emitting device 130R has the configuration as shown in the embodiment 2. It has a first electrode (pixel electrode) composed of a conductive layer 151R and a conductive layer 152R, an organic compound layer 103R on the first electrode, a common layer 104 on the organic compound layer 103R, and a second electrode (common electrode) 102 on the common layer 104.

[0197] The common layer 104 is not necessarily required. By providing the common layer 104, damage to the organic compound layer 103R in a later process can be reduced. When the common layer 104 is provided, the common layer 104 may function as an electron injection layer. When the common layer 104 functions as an electron injection layer, the laminated structure of the organic compound layer 103R and the common layer 104 corresponds to the organic compound layer 103 in the first embodiment.

[0198] Here, the light-emitting device 130 has the structure shown in embodiment 2. It has a first electrode (pixel electrode) composed of a conductive layer 151 and a conductive layer 152, an organic compound layer 103 on the first electrode, a common layer 104 on the organic compound layer 103, and a second electrode (common electrode) 102 on the common layer 104.

[0199] One of the pixel electrode and the common electrode of the light-emitting device functions as an anode and the other functions as a cathode. In the following description, unless otherwise specified, the pixel electrode functions as an anode and the common electrode functions as a cathode.

[0200] The organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B are independent in an island shape, either for each light-emitting color or for each color of light emitted. By providing the organic compound layer 103 in an island shape for each light-emitting device 130, it is possible to suppress leakage current between adjacent light-emitting devices 130 even in a high-definition light-emitting device. This makes it possible to prevent crosstalk and realize a light-emitting device with extremely high contrast. In particular, it is possible to realize a light-emitting device with high current efficiency at low luminance.

[0201] The organic compound layer 103 may be provided so as to cover the upper surface and side surface of the first electrode (pixel electrode) of the light-emitting device 130. This makes it easier to increase the aperture ratio of the light-emitting device 1000 compared to a configuration in which the end of the organic compound layer 103 is located inside the end of the pixel electrode. In addition, by covering the side surface of the pixel electrode of the light-emitting device 130 with the organic compound layer 103, the pixel electrode and the second electrode 102 can be prevented from coming into contact with each other, so that a short circuit of the light-emitting device 130 can be prevented. In addition, the distance between the light-emitting region of the organic compound layer 103 (i.e., the region overlapping with the pixel electrode) and the end of the organic compound layer 103 can be increased. Furthermore, since the end of the organic compound layer 103 may be damaged by processing, the reliability of the light-emitting device 130 can be improved by using an area away from the end of the organic compound layer 103 as the light-emitting region.

[0202] In the light-emitting device of one embodiment of the present invention, the first electrode (pixel electrode) of the light-emitting device may have a stacked structure. For example, in the example shown in FIG. 3B, the first electrode of the light-emitting device 130 has a stacked structure of a conductive layer 151 and a conductive layer 152.

[0203] For example, when the light-emitting device 1000 is a top-emission type, it is preferable that the pixel electrode of the light-emitting device 130 has a conductive layer 151 having a high reflectance to visible light and a conductive layer 152 having a visible light transmittance and a large work function. The higher the reflectance of the pixel electrode to visible light, the higher the extraction efficiency of the light emitted by the organic compound layer 103 can be. In addition, when the pixel electrode functions as an anode, the higher the work function of the pixel electrode, the easier it is to inject holes into the organic compound layer 103. Therefore, by forming the pixel electrode of the light-emitting device 130 into a laminated structure of the conductive layer 151 having a high reflectance to visible light and the conductive layer 152 having a high work function, the light-emitting device 130 can be a light-emitting device with high light extraction efficiency and low driving voltage.

[0204] Specifically, the reflectance of the conductive layer 151 to visible light is preferably, for example, 40% to 100%, and more preferably, 70% to 100%. When the conductive layer 152 is an electrode having transparency to visible light, it is preferable that the transmittance of the conductive layer 152 to visible light is, for example, 40% or more.

[0205] In addition, when removing a film formed after forming a pixel electrode having a laminated structure by a wet etching method or the like, the structure may be impregnated with a chemical solution used for etching. If the impregnated chemical solution comes into contact with the pixel electrode, galvanic corrosion or the like may occur between the multiple layers constituting the pixel electrode, and the pixel electrode may be altered.

[0206] Therefore, it is preferable to form the conductive layer 152 so as to cover the upper surface and side surfaces of the conductive layer 151. By covering the conductive layer 151 with the conductive layer 152, the impregnated chemical solution does not come into contact with the conductive layer 151, and the occurrence of galvanic corrosion in the pixel electrode can be suppressed. Therefore, the light-emitting device 1000 can be manufactured by a method with a high yield rate, and therefore the light-emitting device can be made low-cost. Furthermore, the occurrence of defects in the light-emitting device 1000 can be suppressed, and therefore the light-emitting device 1000 can be made highly reliable.

[0207] For example, a metal material can be used as the conductive layer 151. Specifically, metals such as aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), neodymium (Nd), and alloys containing appropriate combinations of these metals can also be used.

[0208] The conductive layer 152 can be made of an oxide containing one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon. For example, it is preferable to use a conductive oxide containing one or more of indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, zinc oxide containing gallium, titanium oxide, indium zinc oxide containing gallium, indium zinc oxide containing aluminum, indium tin oxide containing silicon, and indium zinc oxide containing silicon. In particular, indium tin oxide containing silicon has a large work function, for example, a work function of 4.0 eV or more, and therefore can be suitably used for the conductive layer 152.

[0209] The conductive layer 151 and the conductive layer 152 may have a stacked structure of a plurality of layers having different materials. In this case, the conductive layer 151 may have a layer using a material that can be used for the conductive layer 152, such as a conductive oxide, or the conductive layer 152 may have a layer using a material that can be used for the conductive layer 151, such as a metal material. For example, when the conductive layer 151 has a stacked structure of two or more layers, a layer in contact with the conductive layer 152 can be a layer containing the same material as the material used for the layer of the conductive layer 152 in contact with the conductive layer 151.

[0210] Note that the conductive layer 151 preferably has a tapered end. Specifically, the conductive layer 151 preferably has a tapered end with a taper angle of less than 90°. In this case, the conductive layer 152 provided along the side surface of the conductive layer 151 also has a tapered end. By making the end of the conductive layer 152 tapered, the coverage of the organic compound layer 103 provided along the side surface of the conductive layer 152 can be improved.

[0211] In the case where the conductive layer 151 or the conductive layer 152 has a layered structure, at least one side surface of the conductive layer 151 or the conductive layer 152 preferably has a tapered shape. In the layered structure constituting each conductive layer, each layer may have a different tapered shape.

[0212] FIG. 4A shows a case where the conductive layer 151 has a stacked structure of multiple layers containing different materials. As shown in FIG. 4A, the conductive layer 151 has a structure including a conductive layer 151_1, a conductive layer 151_2 on the conductive layer 151_1, and a conductive layer 151_3 on the conductive layer 151_2. That is, the conductive layer 151 shown in FIG. 4A has a three-layer stacked structure. In this way, when the conductive layer 151 has a stacked structure of multiple layers, the reflectance of at least one of the layers constituting the conductive layer 151 to visible light may be made higher than the reflectance of the conductive layer 152 to visible light.

[0213] 4A, the conductive layer 151_2 is sandwiched between the conductive layer 151_1 and the conductive layer 151_3. The conductive layer 151_1 and the conductive layer 151_3 are preferably made of a material that is less likely to change in quality than the conductive layer 151_2. For example, the conductive layer 151_1 can be made of a material that is less likely to cause migration due to contact with the insulating layer 175 than the conductive layer 151_2. The conductive layer 151_3 can be made of a material that is less likely to oxidize than the conductive layer 151_2 and has an oxide with a lower electrical resistivity than the oxide of the material used for the conductive layer 151_2.

[0214] As described above, by sandwiching the conductive layer 151_2 between the conductive layer 151_1 and the conductive layer 151_3, the range of material selection for the conductive layer 151_2 can be expanded. As a result, for example, the conductive layer 151_2 can be a layer having a higher reflectance to visible light than at least one of the conductive layer 151_1 and the conductive layer 151_3. For example, aluminum can be used for the conductive layer 151_2. Note that an alloy containing aluminum may be used for the conductive layer 151_2. Furthermore, titanium, which is a material that has a lower reflectance to visible light than aluminum but is less likely to cause migration than aluminum even when in contact with the insulating layer 175, can be used for the conductive layer 151_1. Furthermore, titanium, which is a material that has a lower reflectance to visible light than aluminum but is less likely to oxidize than aluminum and has an oxide electrical resistivity lower than that of aluminum oxide, can be used for the conductive layer 151_3.

[0215] Alternatively, silver or an alloy containing silver may be used as the conductive layer 151_3. Silver has a characteristic that the reflectance of silver to visible light is higher than that of titanium. Furthermore, silver is less likely to oxidize than aluminum, and the electrical resistivity of silver oxide is lower than that of aluminum oxide. As described above, when silver or an alloy containing silver is used as the conductive layer 151_3, the reflectance of the conductive layer 151 to visible light can be suitably increased, while the increase in the electrical resistance of the pixel electrode due to the oxidation of the conductive layer 151_2 can be suppressed. Here, as the alloy containing silver, for example, an alloy of silver, palladium, and copper (Ag-Pd-Cu, also referred to as APC) can be applied. Note that when silver or an alloy containing silver is used as the conductive layer 151_3 and aluminum is used as the conductive layer 151_2, the reflectance of the conductive layer 151_3 to visible light can be made higher than the reflectance of the conductive layer 151_2 to visible light. Here, silver or an alloy containing silver may be used as the conductive layer 151_2. Alternatively, the conductive layer 151_1 may be made of silver or an alloy containing silver.

[0216] On the other hand, a film using titanium has better processability by etching than a film using silver. Therefore, by using titanium for the conductive layer 151_3, the conductive layer 151_3 can be easily formed. Note that a film using aluminum also has better processability by etching than a film using silver.

[0217] As described above, the characteristics of the light-emitting device can be improved by forming the conductive layer 151 with a stacked structure of a plurality of layers. For example, the light-emitting device 1000 can have high light extraction efficiency and high reliability.

[0218] Here, when a microcavity structure is applied to the light-emitting device 130, the light extraction efficiency of the light-emitting device 1000 can be suitably improved by using silver or an alloy containing silver, which is a material with high reflectivity for visible light, as the conductive layer 151_3.

[0219] 4A, depending on the material selection or processing method of the conductive layer 151, the side surface of the conductive layer 151_2 may be located inside the side surfaces of the conductive layer 151_1 and the conductive layer 151_3 to form a protruding portion. This may reduce the coverage of the conductive layer 152 with respect to the conductive layer 151, and may cause a step discontinuity in the conductive layer 152.

[0220] Therefore, it is preferable to provide an insulating layer 156 as shown in Fig. 4A. Fig. 4A shows an example in which the insulating layer 156 is provided over the conductive layer 151_1 so as to have a region overlapping with a side surface of the conductive layer 151_2. This can prevent the conductive layer 152 from being broken or thinned due to the protrusion, thereby suppressing poor connection or an increase in driving voltage.

[0221] 4A illustrates a structure in which the side surface of the conductive layer 151_2 is entirely covered with the insulating layer 156, but the side surface of the conductive layer 151_2 may not be partially covered with the insulating layer 156. Similarly, in pixel electrodes having structures to be described later, the side surface of the conductive layer 151_2 may not be partially covered with the insulating layer 156.

[0222] 4(A), the insulating layer 156 preferably has a curved surface. This can suppress the occurrence of step discontinuities in the conductive layer 152 covering the insulating layer 156, compared to when the side surface of the insulating layer 156 is vertical (parallel to the Z direction). Even when the insulating layer 156 has a tapered shape on the side surface, specifically a tapered shape with a taper angle of less than 90°, the occurrence of step discontinuities in the conductive layer 152 covering the insulating layer 156 can be suppressed, compared to when the side surface of the insulating layer 156 is vertical. As described above, the light emitting device 1000 can be manufactured by a method with a high yield rate. Furthermore, the occurrence of defects can be suppressed, and the light emitting device 1000 can be a highly reliable light emitting device.

[0223] Note that one embodiment of the present invention is not limited to this. For example, other structures of the first electrode 101 are shown in FIG.

[0224] FIG. 4B shows a configuration in which the insulating layer 156 covers not only the side surface of the conductive layer 151_2 but also the side surfaces of the conductive layers 151_1, 151_2, and 151_3 in the first electrode 101 of FIG. 4A.

[0225] FIG. 4C shows a structure in which the insulating layer 156 is not provided in the first electrode 101 of FIG. 4A.

[0226] FIG. 4D shows a structure in which the conductive layer 151 does not have a layered structure and the conductive layer 152 has a layered structure in the first electrode 101 in FIG. 4A.

[0227] The conductive layer 152_1 has higher adhesion to the conductive layer 152_2 than the insulating layer 175, for example. For the conductive layer 152_1, an oxide containing one or more of indium, tin, zinc, gallium, titanium, aluminum, and silicon can be used. For example, a conductive oxide containing one or more of indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, zinc oxide containing gallium, titanium oxide, indium titanium oxide, zinc titanate, aluminum zinc oxide, indium zinc oxide containing gallium, indium zinc oxide containing aluminum, indium tin oxide containing silicon, and indium zinc oxide containing silicon can be preferably used. As described above, peeling of the conductive layer 152_2 can be suppressed. In addition, the conductive layer 152_2 can be configured not to be in contact with the insulating layer 175.

[0228] The conductive layer 152_2 has a higher reflectance to visible light (for example, reflectance to light having a predetermined wavelength in the range of 400 nm to less than 750 nm) than the conductive layer 151, the conductive layer 152_1, and the conductive layer 152_3. The reflectance of the conductive layer 152_2 to visible light can be, for example, 70% to 100%, preferably 80% to 100%, and more preferably 90% to 100%. For example, silver or an alloy containing silver can be used as the conductive layer 152_2. For example, an alloy containing silver can be an alloy of silver, palladium, and copper (APC). As described above, the light-emitting device 1000 can be a light-emitting device with high light extraction efficiency. Note that a metal other than silver may be used as the conductive layer 152_2.

[0229] When the conductive layer 151 and the conductive layer 152 function as an anode, the conductive layer 152_3 is preferably a layer having a high work function. The conductive layer 152_3 is, for example, a layer having a higher work function than the conductive layer 152_2. The conductive layer 152_3 can be formed using, for example, a material similar to that which can be used for the conductive layer 152_1. For example, the conductive layer 152_1 and the conductive layer 152_3 can be formed using the same material.

[0230] Note that in the case where the conductive layer 151 and the conductive layer 152 function as cathodes, the conductive layer 152_3 preferably has a low work function, for example, a layer having a work function smaller than that of the conductive layer 152_2.

[0231] In addition, the conductive layer 152_3 is preferably a layer having a high transmittance for visible light (for example, transmittance for light having a predetermined wavelength in the range of 400 nm or more and less than 750 nm). For example, the transmittance for visible light of the conductive layer 152_3 is preferably higher than the transmittance for visible light of the conductive layer 151 and the conductive layer 152_2. For example, the transmittance for visible light of the conductive layer 152_3 can be 60% or more and 100% or less, preferably 70% or more and 100% or less, and more preferably 80% or more and 100% or less. As a result, the amount of light absorbed by the conductive layer 152_3 out of the light emitted by the organic compound layer 103 can be reduced. In addition, as described above, the conductive layer 152_2 under the conductive layer 152_3 can be a layer having a high reflectance for visible light. Therefore, the light-emitting device 1000 can be a light-emitting device having high light extraction efficiency.

[0232] Next, an example of a method for manufacturing the light emitting device 1000 having the structure shown in FIG. 3 will be described with reference to FIGS.

[0233] [Example of manufacturing method] The thin films (insulating film, semiconductor film, conductive film, etc.) constituting the light-emitting device can be formed by using a sputtering method, a chemical vapor deposition (CVD) method, a vacuum deposition method, a pulsed laser deposition (PLD) method, an ALD method, etc. CVD methods include a plasma enhanced chemical vapor deposition (PECVD) method and a thermal CVD method. Another thermal CVD method is a metal organic chemical vapor deposition (MOCVD) method.

[0234] Furthermore, the thin films (insulating films, semiconductor films, conductive films, etc.) constituting the light-emitting device can be formed by a wet film formation method such as spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, the doctor knife method, slit coating, roll coating, curtain coating, or knife coating.

[0235] In particular, for the production of light-emitting devices, vacuum processes such as deposition methods and solution processes such as spin coating and inkjet methods can be used. Examples of deposition methods include physical deposition methods (PVD methods) such as sputtering, ion plating, ion beam deposition, molecular beam deposition, and vacuum deposition, and chemical deposition methods (CVD methods). In particular, functional layers (hole injection layer, hole transport layer, hole blocking layer, light-emitting layer, electron blocking layer, electron transport layer, and electron injection layer, etc.) included in the organic compound layer can be formed by deposition methods (vacuum deposition methods, etc.), coating methods (dip coating, die coating, bar coating, spin coating, spray coating, etc.), printing methods (inkjet methods, screen (screen printing) methods, offset (lithographic printing) methods, flexo (letterpress printing) methods, gravure methods, microcontact methods, etc.), etc.

[0236] Furthermore, when processing the thin film constituting the light emitting device, it can be processed using, for example, a photolithography method. Alternatively, the thin film may be processed using a nanoimprint method, a sandblasting method, a lift-off method, etc. Furthermore, an island-shaped thin film may be directly formed by a film formation method using a shielding mask such as a metal mask.

[0237] There are two typical photolithography methods. One is a method in which a resist mask is formed on the thin film to be processed, the thin film is processed by, for example, etching, and the resist mask is then removed. The other is a method in which a photosensitive thin film is formed, and then exposed and developed to process the thin film into the desired shape.

[0238] The thin film can be etched by dry etching, wet etching, sandblasting, or the like.

[0239] 5(A), an insulating layer 171 is formed on a substrate (not shown). Then, a conductive layer 172 and a conductive layer 179 are formed on the insulating layer 171, and an insulating layer 173 is formed on the insulating layer 171 so as to cover the conductive layer 172 and the conductive layer 179. Then, an insulating layer 174 is formed on the insulating layer 173, and an insulating layer 175 is formed on the insulating layer 174.

[0240] The substrate may be a substrate having at least a heat resistance sufficient to withstand a subsequent heat treatment. When an insulating substrate is used, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, an organic resin substrate, or the like may be used. In addition, a semiconductor substrate such as a single crystal semiconductor substrate, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, or an SOI substrate, made of silicon or silicon carbide, or the like may be used.

[0241] 5A, an opening reaching the conductive layer 172 is formed in the insulating layer 175, the insulating layer 174, and the insulating layer 173. Then, a plug 176 is formed to fill the opening.

[0242] 5A, a conductive film 151f, which will later become the conductive layers 151R, 151G, 151B, and 151C, is formed on the plug 176 and the insulating layer 175. The conductive film 151f can be formed by, for example, a sputtering method or a vacuum deposition method. The conductive film 151f can be made of, for example, a metal material.

[0243] 5A, for example, a resist mask 191 is formed over the conductive film 151f. The resist mask 191 can be formed by applying a photosensitive material (photoresist) and performing exposure and development.

[0244] 5B, the conductive film 151f in a region that does not overlap with the resist mask 191 is removed by, for example, an etching method, specifically, a dry etching method. When the conductive film 151f includes a layer using a conductive oxide such as indium tin oxide, the layer may be removed by a wet etching method. As a result, the conductive layer 151 is formed. When part of the conductive film 151f is removed by a dry etching method, for example, a recess (also referred to as a countersink) may be formed in a region of the insulating layer 175 that does not overlap with the conductive layer 151.

[0245] 5(C), the resist mask 191 is removed. The resist mask 191 can be removed by ashing using oxygen plasma, for example. Alternatively, oxygen gas and a Group 18 element such as CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, or He may be used. Alternatively, the resist mask 191 may be removed by wet etching.

[0246] 5(D), an insulating film 156f, which will later become the insulating layers 156R, 156G, 156B, and 156C, is formed on the conductive layers 151R, 151G, 151B, and 151C, and on the insulating layer 175. The insulating film 156f can be formed by, for example, a CVD method, an ALD method, a sputtering method, or a vacuum deposition method.

[0247] The insulating film 156f can be made of an inorganic material. For example, an inorganic insulating film such as an oxide insulating film, a nitride insulating film, an oxynitride insulating film, or a nitride oxide insulating film can be used for the insulating film 156f. For example, an oxide insulating film, a nitride insulating film, an oxynitride insulating film, or a nitride oxide insulating film containing silicon can be used for the insulating film 156f. For example, silicon oxynitride can be used for the insulating film 156f.

[0248] 5(E), the insulating film 156f is processed to form the insulating layers 156R, 156G, 156B, and 156C. For example, the insulating layer 156 can be formed by uniformly etching the upper surface of the insulating film 156f. Such uniform etching and planarization is also called an etch-back process. The insulating layer 156 may be formed by photolithography.

[0249] 6A, a conductive film 152f to be the conductive layer 152R, the conductive layer 152G, the conductive layer 152B, and the conductive layer 152C is formed on the conductive layer 151R, the conductive layer 151G, the conductive layer 151B, the conductive layer 151C, the insulating layer 156R, the insulating layer 156G, the insulating layer 156B, the insulating layer 156C, and the insulating layer 175. Specifically, the conductive film 152f is formed so as to cover, for example, the conductive layer 151R, the conductive layer 151G, the conductive layer 151B, the conductive layer 151C, the insulating layer 156R, the insulating layer 156G, the insulating layer 156B, and the insulating layer 156C.

[0250] The conductive film 152f can be formed by, for example, a sputtering method or a vacuum evaporation method. The conductive film 152f can be formed by, for example, an ALD method. The conductive film 152f can be formed using, for example, a conductive oxide. Alternatively, the conductive film 152f can have a stacked structure of a film using a metal material and a film using a conductive oxide on the film. For example, the conductive film 152f can have a stacked structure of a film using titanium, silver, or an alloy containing silver and a film using a conductive oxide on the film.

[0251] 6B, the conductive film 152f is processed by, for example, photolithography to form the conductive layers 152R, 152G, 152B, and 152C. Specifically, for example, after forming a resist mask, part of the conductive film 152f is removed by etching. The conductive film 152f can be removed by, for example, wet etching. Note that the conductive film 152f may also be removed by dry etching. In this manner, a pixel electrode including the conductive layer 151 and the conductive layer 152 is formed.

[0252] Subsequently, it is preferable to perform hydrophobization treatment on the conductive layer 152. The hydrophobization treatment can change the surface to be treated from hydrophilic to hydrophobic, or can increase the hydrophobicity of the surface to be treated. By performing the hydrophobization treatment on the conductive layer 152, the adhesion between the conductive layer 152 and the organic compound layer 103 formed in a later step can be increased, and film peeling can be suppressed. Note that the hydrophobization treatment is not necessarily performed.

[0253] 6C, an organic compound film 103Bf, which will later become the organic compound layer 103B, is formed on the conductive layer 152B, the conductive layer 152G, the conductive layer 152R, and the insulating layer 175. Then, as shown in FIG.

[0254] In the present invention, the organic compound film 103Bf has a plurality of organic compound layers each having at least one light-emitting layer. Specifically, the structure of the light-emitting device described in the second embodiment can be referred to. Alternatively, the organic compound film 103Bf may have a structure in which a plurality of organic compound layers each having at least one light-emitting layer are laminated with an intermediate layer interposed therebetween.

[0255] As shown in Fig. 6(C), the organic compound film 103Bf is not formed on the conductive layer 152C. For example, by using a mask for defining a deposition area (also called an area mask or a rough metal mask, to distinguish it from a fine metal mask), the organic compound film 103Bf can be deposited only in a desired area. By employing a deposition process using an area mask and a processing process using a resist mask, a light-emitting device can be manufactured by a relatively simple process.

[0256] The organic compound film 103Bf can be formed by, for example, a deposition method, specifically, a vacuum deposition method. Alternatively, the organic compound film 103Bf may be formed by a transfer method, a printing method, an inkjet method, a coating method, or the like.

[0257] Subsequently, as shown in FIG. 6(D), a sacrificial film 158Bf, which will later become the sacrificial layer 158B, and a mask film 159Bf, which will later become the mask layer 159B, are formed in this order on the organic compound film 103Bf.

[0258] The sacrificial film 158Bf and the mask film 159Bf may be formed by, for example, sputtering, ALD (thermal ALD, PEALD), CVD, or vacuum deposition. Alternatively, the sacrificial film 158Bf and the mask film 159Bf may be formed by the above-mentioned wet film formation method.

[0259] The sacrificial film 158Bf and the mask film 159Bf are formed at a temperature lower than the heat-resistant temperature of the organic compound film 103Bf. The substrate temperature when forming the sacrificial film 158Bf and the mask film 159Bf is typically 200° C. or less, preferably 150° C. or less, more preferably 120° C. or less, more preferably 100° C. or less, and further preferably 80° C. or less.

[0260] In this embodiment, an example is shown in which the mask film is formed with a two-layer structure of the sacrificial film 158Bf and the mask film 159Bf, but the mask film may have a single-layer structure or a laminated structure of three or more layers.

[0261] By providing a sacrificial film on the organic compound film 103Bf, damage to the organic compound film 103Bf during the manufacturing process of the light-emitting device can be reduced, and the reliability of the light-emitting device can be improved.

[0262] The sacrificial film 158Bf is made of a film having high resistance to the processing conditions of the organic compound film 103Bf, specifically, a film having a high etching selectivity with respect to the organic compound film 103Bf. The mask film 159Bf is made of a film having a high etching selectivity with respect to the sacrificial film 158Bf.

[0263] The sacrificial film 158Bf and the mask film 159Bf are preferably made of a film that can be removed by a wet etching method. By using the wet etching method, damage to the organic compound film 103Bf during processing of the sacrificial film 158Bf and the mask film 159Bf can be reduced compared to the case of using the dry etching method.

[0264] When using the wet etching method, it is particularly preferable to use an acidic chemical solution, such as a chemical solution containing any one of phosphoric acid, hydrofluoric acid, nitric acid, acetic acid, oxalic acid, and sulfuric acid, or a mixed chemical solution of two or more kinds of acids (also called mixed acid).

[0265] The sacrificial film 158Bf and the mask film 159Bf may each be made of one or more of a metal film, an alloy film, a metal oxide film, a semiconductor film, an organic insulating film, an inorganic insulating film, or the like.

[0266] In addition, by using a film containing a material having a light-shielding property against ultraviolet rays for the sacrificial film 158Bf and the mask film 159Bf, it is possible to prevent the organic compound layer from being irradiated with ultraviolet rays in, for example, an exposure process. By preventing the organic compound layer from being damaged by ultraviolet rays, it is possible to improve the reliability of the light-emitting device.

[0267] The same effect can be obtained when a film containing a material having a light blocking property against ultraviolet rays is used as the material of the inorganic insulating film 125f described later.

[0268] The sacrificial film 158Bf and the mask film 159Bf may be made of, for example, a metal material such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, or tantalum, or an alloy material containing the metal material. In particular, it is preferable to use a low melting point material such as aluminum or silver.

[0269] In addition, for the sacrificial film 158Bf and the mask film 159Bf, metal oxides such as In-Ga-Zn oxide, indium oxide, In-Zn oxide, In-Sn oxide, indium titanium oxide (In-Ti oxide), indium tin zinc oxide (In-Sn-Zn oxide), indium titanium zinc oxide (In-Ti-Zn oxide), indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide), and indium tin oxide containing silicon can be used.

[0270] In addition, instead of the above gallium, an element M (M is one or more elements selected from aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium) may be used.

[0271] In addition, it is preferable to use a semiconductor material such as silicon or germanium as the sacrificial film 158Bf and the mask film 159Bf because it has a high affinity with the semiconductor manufacturing process. An oxide or nitride of the above semiconductor material can be used. Alternatively, a nonmetallic material such as carbon or a compound thereof can be used. Alternatively, metals such as titanium, tantalum, tungsten, chromium, aluminum, or alloys containing one or more of these can be used. Alternatively, an oxide containing the above metals such as titanium oxide or chromium oxide, or a nitride such as titanium nitride, chromium nitride, or tantalum nitride can be used.

[0272] Moreover, various inorganic insulating films can be used for the sacrificial film 158Bf and the mask film 159Bf. In particular, an oxide insulating film is preferable because it has a higher adhesion to the organic compound film 103Bf than a nitride insulating film. For example, an inorganic insulating material such as aluminum oxide, hafnium oxide, silicon oxide, etc. can be used for the sacrificial film 158Bf and the mask film 159Bf. For example, an aluminum oxide film can be formed as the sacrificial film 158Bf and the mask film 159Bf by using the ALD method. Using the ALD method is preferable because it can reduce damage to the underlayer (particularly the organic compound layer).

[0273] In addition, an organic material may be used for one or both of the sacrificial film 158Bf and the mask film 159Bf. For example, a material that can be dissolved in a chemically stable solvent may be used as the organic material for at least the film located at the top of the organic compound film 103Bf. In particular, a material that can be dissolved in water or alcohol can be preferably used. When forming a film of such a material, it is preferable to apply the material by a wet film forming method in a state where the material is dissolved in a solvent such as water or alcohol, and then perform a heat treatment to evaporate the solvent. At this time, by performing the heat treatment under a reduced pressure atmosphere, the solvent can be removed at a low temperature in a short time, which is preferable because it reduces thermal damage to the organic compound film 103Bf.

[0274] The sacrificial film 158Bf and the mask film 159Bf may each be made of an organic resin such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, alcohol-soluble polyamide resin, or a fluororesin such as a perfluoropolymer.

[0275] For example, the sacrificial film 158Bf may be an organic film (e.g., a PVA film) formed using either a vapor deposition method or the above-mentioned wet film formation method, and the mask film 159Bf may be an inorganic film (e.g., a silicon nitride film) formed using a sputtering method.

[0276] 6(D), a resist mask 190B is formed on the mask film 159Bf. The resist mask 190B can be formed by applying a photosensitive material (photoresist) and then performing exposure and development.

[0277] The resist mask 190B may be made of either a positive resist material or a negative resist material.

[0278] The resist mask 190B is provided at a position overlapping with the conductive layer 152B. The resist mask 190B is preferably provided also at a position overlapping with the conductive layer 152C. This can prevent the conductive layer 152C from being damaged during the manufacturing process of the light-emitting device. Note that the resist mask 190B does not necessarily have to be provided on the conductive layer 152C. Moreover, the resist mask 190B is preferably provided so as to cover from an end of the organic compound film 103Bf to an end of the conductive layer 152C (the end on the organic compound film 103Bf side) as shown in the cross-sectional view between B1 and B2 in FIG. 6(C).

[0279] 6(E), a part of the mask film 159Bf is removed using the resist mask 190B to form a mask layer 159B. The mask layer 159B remains on the conductive layer 152B and the conductive layer 152C. Then, the resist mask 190B is removed. Then, a part of the sacrificial film 158Bf is removed using the mask layer 159B as a mask (also called a hard mask) to form a sacrificial layer 158B.

[0280] The sacrificial film 158Bf and the mask film 159Bf can be processed by wet etching or dry etching, respectively. The sacrificial film 158Bf and the mask film 159Bf are preferably processed by wet etching.

[0281] By using the wet etching method, damage to the organic compound film 103Bf during processing of the sacrificial film 158Bf and the mask film 159Bf can be reduced compared to the case of using the dry etching method. When using the wet etching method, it is preferable to use a chemical solution using, for example, a developer, a tetramethylammonium hydroxide solution (TMAH), dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or a mixture of these.

[0282] In processing the mask film 159Bf, the organic compound film 103Bf is not exposed, so the range of processing methods to be selected is wider than in processing the sacrificial film 158Bf. Specifically, even if a gas containing oxygen is used as an etching gas in processing the mask film 159Bf, deterioration of the organic compound film 103Bf can be further suppressed.

[0283] When using the wet etching method, it is particularly preferable to use an acidic chemical solution, such as a chemical solution containing any one of phosphoric acid, hydrofluoric acid, nitric acid, acetic acid, oxalic acid, and sulfuric acid, or a mixed chemical solution of two or more kinds of acids (also called mixed acid).

[0284] In addition, when a dry etching method is used in processing the sacrificial film 158Bf, deterioration of the organic compound film 103Bf can be suppressed by not using a gas containing oxygen as an etching gas. When a dry etching method is used, it is preferable to use a gas containing a Group 18 element such as CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, or He as an etching gas.

[0285] The resist mask 190B can be removed in the same manner as the resist mask 191. At this time, since the sacrificial film 158Bf is located on the outermost surface and the organic compound film 103Bf is not exposed, damage to the organic compound film 103Bf can be suppressed in the process of removing the resist mask 190B. In addition, the range of options for removing the resist mask 190B can be expanded.

[0286] 6(E), the organic compound film 103Bf is processed to form the organic compound layer 103B. For example, the mask layer 159B and the sacrificial layer 158B are used as a hard mask to remove a part of the organic compound film 103Bf to form the organic compound layer 103B.

[0287] 6E, a laminated structure of the organic compound layer 103B, the sacrificial layer 158B, and the mask layer 159B remains on the conductive layer 152B. Also, the conductive layer 152G and the conductive layer 152R are exposed.

[0288] The organic compound film 103Bf can be processed by dry etching or wet etching. For example, when processing by dry etching, an etching gas containing oxygen can be used. When the etching gas contains oxygen, the etching speed can be increased. Therefore, etching can be performed under low power conditions while maintaining a sufficiently high etching speed. Therefore, damage to the organic compound film 103Bf can be suppressed. Furthermore, problems such as adhesion of reaction products generated during etching can be suppressed.

[0289] Alternatively, an etching gas that does not contain oxygen may be used, for example, by using an etching gas that does not contain oxygen, deterioration of the organic compound film 103Bf can be suppressed.

[0290] As described above, in one embodiment of the present invention, the resist mask 190B is formed over the mask film 159Bf, and part of the mask film 159Bf is removed using the resist mask 190B to form the mask layer 159B. Then, part of the organic compound film 103Bf is removed using the mask layer 159B as a hard mask to form the organic compound layer 103B. Thus, it can be said that the organic compound layer 103B is formed by processing the organic compound film 103Bf by a photolithography method. Note that part of the organic compound film 103Bf may be removed using the resist mask 190B. Then, the resist mask 190B may be removed.

[0291] Here, the conductive layer 152G may be subjected to hydrophobic treatment as necessary. During processing of the organic compound film 103Bf, for example, the surface state of the conductive layer 152G may change to hydrophilic. For example, by subjecting the conductive layer 152G to hydrophobic treatment, for example, the adhesion between the conductive layer 152G and a layer (here, the organic compound layer 103G) formed in a later process can be improved, and film peeling can be suppressed.

[0292] 7A, an organic compound film 103Gf, which will later become the organic compound layer 103G, is formed on the conductive layer 152G, the conductive layer 152R, the mask layer 159B, and the insulating layer 175. Then, as shown in FIG.

[0293] The organic compound film 103Gf can be formed by the same method as that used for forming the organic compound film 103Bf, and can have the same structure as the organic compound film 103Bf.

[0294] 7(B), a sacrificial film 158Gf that will later become the sacrificial layer 158G and a mask film 159Gf that will later become the mask layer 159G are sequentially formed on the organic compound film 103Gf and the mask layer 159B. Then, a resist mask 190G is formed. The material and the forming method of the sacrificial film 158Gf and the mask film 159Gf are the same as those applicable to the sacrificial film 158Bf and the mask film 159Bf. The material and the forming method of the resist mask 190G are the same as those applicable to the resist mask 190B.

[0295] The resist mask 190G is provided in a position overlapping with the conductive layer 152G.

[0296] 7(C), a resist mask 190G is used to remove a portion of the mask film 159Gf to form a mask layer 159G. The mask layer 159G remains on the conductive layer 152G. The resist mask 190G is then removed. The mask layer 159G is then used as a mask to remove a portion of the sacrificial film 158Gf to form a sacrificial layer 158G. The organic compound film 103Gf is then processed to form an organic compound layer 103G. For example, the mask layer 159G and the sacrificial layer 158G are used as a hard mask to remove a portion of the organic compound film 103Gf to form the organic compound layer 103G.

[0297] 7C, a laminated structure of the organic compound layer 103G, the sacrificial layer 158G, and the mask layer 159G remains on the conductive layer 152G. Also, the mask layer 159B and the conductive layer 152R are exposed.

[0298] In addition, for example, a hydrophobic treatment may be performed on the conductive layer 152R.

[0299] Subsequently, an organic compound film 103Rf, which will later become the organic compound layer 103R, is formed on the conductive layer 152R, the mask layer 159G, the mask layer 159B, and the insulating layer 175, as shown in FIG. 8A.

[0300] The organic compound film 103Rf can be formed by the same method as that used for forming the organic compound film 103Gf, and can have the same configuration as the organic compound film 103Gf.

[0301] 8(B) and 8(C), a sacrificial layer 158R is formed from the sacrificial film 158Rf, a mask layer 159R is formed from the mask film 159Rf, or an organic compound layer 103R is formed from the organic compound film 103Rf using a resist mask 190R. The description of the organic compound layer 103G can be referred to for the methods of forming the sacrificial layer 158R, the mask layer 159R, and the organic compound layer 103R.

[0302] It is preferable that the side surfaces of the organic compound layers 103B, 103G, and 103R are perpendicular or substantially perpendicular to the surface on which they are formed. For example, it is preferable that the angle between the surface on which they are formed and these side surfaces is 60 degrees or more and 90 degrees or less.

[0303] As described above, the distance between two adjacent ones of the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R formed by photolithography can be narrowed to 8 μm or less, 5 μm or less, 3 μm or less, 2 μm or less, or 1 μm or less. Here, the distance can be defined, for example, as the distance between two adjacent opposing ends of the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R. In this way, by narrowing the distance between the island-shaped organic compound layers, a light-emitting device having high definition and a large aperture ratio can be provided. In addition, the distance between the first electrodes between adjacent light-emitting devices can also be narrowed, and can be, for example, 10 μm or less, 8 μm or less, 5 μm or less, 3 μm or less, or 2 μm or less. Note that the distance between the first electrodes between adjacent light-emitting devices is preferably 2 μm or more and 5 μm or less.

[0304] Next, as shown in FIG. 9A, the mask layers 159B, 159G, and 159R are removed.

[0305] In the present embodiment, the case where the mask layers 159B, 159G, and 159R are removed will be described as an example, but the mask layers 159B, 159G, and 159R do not have to be removed. For example, when the mask layers 159B, 159G, and 159R contain a material having a light blocking property against ultraviolet light as described above, the organic compound layer can be protected from light irradiation (including illumination light) by proceeding to the next step without removing the mask layers.

[0306] The mask layer removal process can be performed using the same method as the mask film processing process. In particular, by using a wet etching method, damage to the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R during the mask layer removal can be reduced compared to the case of using a dry etching method.

[0307] The mask layer may also be removed by dissolving it in a solvent such as water or alcohol, such as ethyl alcohol, methyl alcohol, isopropyl alcohol (IPA), or glycerin.

[0308] After removing the mask layer, a drying treatment may be performed to remove water contained in the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R, and water adsorbed on the surfaces of the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R. For example, a heat treatment can be performed in an inert atmosphere or a reduced pressure atmosphere. The heat treatment can be performed at a substrate temperature of 50° C. or higher and 200° C. or lower, preferably 60° C. or higher and 150° C. or lower, and more preferably 70° C. or higher and 120° C. or lower. A reduced pressure atmosphere is preferable because drying can be performed at a lower temperature.

[0309] Next, as shown in FIG. 9(B), an inorganic insulating film 125f, which will later become the inorganic insulating layer 125, is formed to cover the organic compound layer 103B, the organic compound layer 103G, the organic compound layer 103R, the sacrificial layer 158B, the sacrificial layer 158G, and the sacrificial layer 158R.

[0310] As described later, an insulating film that will later become the insulating layer 127 is formed in contact with the upper surface of the inorganic insulating film 125f. For this reason, it is preferable that the upper surface of the inorganic insulating film 125f has high affinity with the material (e.g., a photosensitive resin composition containing an acrylic resin) used for the insulating film that will become the insulating layer 127. In order to improve the affinity, a surface treatment may be performed on the upper surface of the inorganic insulating film 125f. Specifically, it is preferable to hydrophobize (or increase the hydrophobicity of) the surface of the inorganic insulating film 125f. For example, it is preferable to perform the treatment using a silylating agent such as hexamethyldisilazane (HMDS). By hydrophobizing the upper surface of the inorganic insulating film 125f in this manner, the insulating film 127f can be formed with good adhesion.

[0311] Subsequently, as shown in FIG. 9C, an insulating film 127f, which will later become the insulating layer 127, is formed on the inorganic insulating film 125f.

[0312] The inorganic insulating film 125f and the insulating film 127f are preferably formed by a formation method that causes less damage to the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R. In particular, since the inorganic insulating film 125f is formed in contact with the side surfaces of the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R, it is preferably formed by a formation method that causes less damage to the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R than the insulating film 127f.

[0313] The inorganic insulating film 125f and the insulating film 127f are formed at a temperature lower than the heat-resistant temperature limits of the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R, respectively. By increasing the substrate temperature during film formation, the inorganic insulating film 125f can be a film with a low impurity concentration and high barrier properties against at least one of water and oxygen, even if it is thin.

[0314] The substrate temperature when forming the inorganic insulating film 125f and the insulating film 127f is preferably 60°C or more, 80°C or more, 100°C or more, or 120°C or more, and 200°C or less, 180°C or less, 160°C or less, 150°C or less, or 140°C or less.

[0315] As the inorganic insulating film 125f, it is preferable to form an insulating film having a thickness of 3 nm or more, 5 nm or more, or 10 nm or more and 200 nm or less, 150 nm or less, 100 nm or less, or 50 nm or less within the above substrate temperature range.

[0316] The inorganic insulating film 125f is preferably formed by, for example, the ALD method. By using the ALD method, damage during film formation can be reduced, and a film with high coverage can be formed, which is preferable. As the inorganic insulating film 125f, for example, an aluminum oxide film is preferably formed by the ALD method.

[0317] Alternatively, the inorganic insulating film 125f may be formed by sputtering, CVD, or PECVD, which have a faster film formation rate than ALD, thereby enabling a highly reliable light emitting device to be manufactured with high productivity.

[0318] The insulating film 127f is preferably formed by using the above-mentioned wet film formation method. The insulating film 127f is preferably formed by using a photosensitive material, for example, by spin coating, and more specifically, is preferably formed by using a photosensitive resin composition containing an acrylic resin.

[0319] The insulating film 127f is preferably formed using a resin composition containing, for example, a polymer, an acid generator, and a solvent. The polymer is formed using one or more types of monomers and has a structure in which one or more types of structural units (also called constituent units) are regularly or irregularly repeated. As the acid generator, one or both of a compound that generates an acid when irradiated with light and a compound that generates an acid when heated can be used. The resin composition may further contain one or more of a photosensitizer, a sensitizer, a catalyst, an adhesion aid, a surfactant, and an antioxidant.

[0320] Moreover, it is preferable to perform heat treatment (also referred to as pre-baking) after the insulating film 127f is formed. The heat treatment is performed at a temperature lower than the heat resistance temperature of the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R. The substrate temperature during the heat treatment is preferably from 50° C. to 200° C., more preferably from 60° C. to 150° C., and further preferably from 70° C. to 120° C. This can remove the solvent contained in the insulating film 127f.

[0321] Next, exposure is performed to expose a part of the insulating film 127f to visible light or ultraviolet light. When a positive-type photosensitive resin composition containing an acrylic resin is used for the insulating film 127f, visible light or ultraviolet light is applied to a region where the insulating layer 127 is not to be formed in a later step. The insulating layer 127 is formed in a region sandwiched between any two of the conductive layers 152B, 152G, and 152R, and around the conductive layer 152C. Therefore, visible light or ultraviolet light is applied to the conductive layers 152B, 152G, 152R, and 152C. When a negative-type photosensitive material is used for the insulating film 127f, visible light or ultraviolet light is applied to a region where the insulating layer 127 is to be formed.

[0322] The width of the insulating layer 127 to be formed later can be controlled by the exposed region of the insulating film 127f. In this embodiment, the insulating layer 127 is processed so as to have a portion overlapping with the upper surface of the conductive layer 151.

[0323] Here, by providing a barrier insulating layer against oxygen (for example, an aluminum oxide film, etc.) as one or both of the sacrificial layer 158 (sacrificial layer 158B, sacrificial layer 158G, and sacrificial layer 158R) and the inorganic insulating film 125f, it is possible to reduce the diffusion of oxygen into the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R. When the organic compound layer is irradiated with light (visible light or ultraviolet light), the organic compound contained in the organic compound layer becomes excited, and the reaction with oxygen contained in the atmosphere may be promoted. More specifically, when light (visible light or ultraviolet light) is irradiated to the organic compound layer in an atmosphere containing oxygen, oxygen may be bonded to the organic compound contained in the organic compound layer. By providing the sacrificial layer 158 and the inorganic insulating film 125f on the island-shaped organic compound layer, it is possible to reduce the bonding of oxygen in the atmosphere to the organic compound contained in the organic compound layer.

[0324] 10(A), development is performed to remove the exposed region of the insulating film 127f, forming an insulating layer 127a. The insulating layer 127a is formed in a region sandwiched between any two of the conductive layers 152B, 152G, and 152R, and in a region surrounding the conductive layer 152C. When an acrylic resin is used for the insulating film 127f, an alkaline solution, such as TMAH, can be used as the developer.

[0325] 10(B), an etching process is performed using the insulating layer 127a as a mask to remove a part of the inorganic insulating film 125f, and to reduce the thickness of the sacrificial layers 158B, 158G, and 158R. As a result, the inorganic insulating layer 125 is formed under the insulating layer 127a. In the following, the etching process for processing the inorganic insulating film 125f using the insulating layer 127a as a mask may be referred to as a first etching process.

[0326] That is, in the first etching process, the sacrificial layer 158B, the sacrificial layer 158G, and the sacrificial layer 158R are not completely removed, and the etching process is stopped when the film thickness becomes thin. In this way, by leaving the corresponding sacrificial layer 158B, the sacrificial layer 158G, and the sacrificial layer 158R on the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R, it is possible to prevent the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R from being damaged in the processing of the subsequent process.

[0327] The first etching process can be performed by dry etching or wet etching. When the inorganic insulating film 125f is formed using the same material as the sacrificial layers 158B, 158G, and 158R, the inorganic insulating film 125f can be processed and the exposed sacrificial layer 158 can be thinned in one go by the first etching process, which is preferable.

[0328] By performing etching using insulating layer 127a with tapered side surfaces as a mask, the side surfaces of inorganic insulating layer 125 and the upper end portions of the side surfaces of sacrificial layers 158B, 158G, and 158R can be tapered relatively easily.

[0329] For example, when the first etching process is performed by dry etching, a chlorine-based gas can be used. As the chlorine-based gas, Cl2, BCl3, SiCl4, CCl4, etc. can be used alone or in a mixture of two or more gases. In addition, oxygen gas, hydrogen gas, helium gas, argon gas, etc. can be appropriately added alone or in a mixture of two or more gases to the chlorine-based gas. By using dry etching, the thin film regions of the sacrificial layers 158B, 158G, and 158R can be formed with good in-plane uniformity.

[0330] Furthermore, for example, the first etching process can be performed by wet etching, which can reduce damage to the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R compared to the case of using dry etching.

[0331] For wet etching, it is preferable to use an acidic chemical solution, such as a chemical solution containing any one of phosphoric acid, hydrofluoric acid, nitric acid, acetic acid, oxalic acid, and sulfuric acid, or a mixed chemical solution of two or more kinds of acids (also called mixed acid).

[0332] Alternatively, an alkaline solution may be used. For example, an alkaline solution, TMAH, may be used for wet etching of an aluminum oxide film. In this case, the wet etching may be performed by a paddle method.

[0333] Next, heat treatment (also referred to as post-bake) is performed. By performing heat treatment, the insulating layer 127a can be transformed into the insulating layer 127 having tapered sides (FIG. 10C). The heat treatment is performed at a temperature lower than the heat resistance temperature of the organic compound layer. The heat treatment can be performed at a substrate temperature of 50° C. to 200° C., preferably 60° C. to 150° C., more preferably 70° C. to 130° C. The heating atmosphere may be an air atmosphere or an inert atmosphere. The heating atmosphere may be an atmospheric pressure atmosphere or a reduced pressure atmosphere. The substrate temperature of the heat treatment in this step is preferably higher than that of the heat treatment (pre-bake) after the formation of the insulating film 127f.

[0334] The heat treatment can improve the adhesion between the insulating layer 127 and the inorganic insulating layer 125, and can also improve the corrosion resistance of the insulating layer 127. In addition, the insulating layer 127a can be deformed so that the end portion of the inorganic insulating layer 125 is covered by the insulating layer 127.

[0335] In the first etching process, the sacrificial layers 158B, 158G, and 158R are not completely removed, and the sacrificial layers 158B, 158G, and 158R are left in a state where their thicknesses are reduced, thereby preventing the organic compound layers 103B, 103G, and 103R from being damaged and deteriorated in the heat treatment, thereby improving the reliability of the light-emitting device.

[0336] 11(A), an etching process is performed using the insulating layer 127 as a mask to remove parts of the sacrificial layer 158B, the sacrificial layer 158G, and the sacrificial layer 158R. At this time, a part of the inorganic insulating layer 125 may also be removed. The etching process forms openings in the sacrificial layer 158B, the sacrificial layer 158G, and the sacrificial layer 158R, and the upper surfaces of the organic compound layer 103B, the organic compound layer 103G, the organic compound layer 103R, and the conductive layer 152C are exposed from the openings. In the following, the etching process using the insulating layer 127 as a mask to expose the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R may be referred to as a second etching process.

[0337] The second etching process is performed by wet etching. By using the wet etching method, damage to the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R can be reduced compared to the case of using the dry etching method. The wet etching can be performed using an acidic chemical solution or an alkaline solution, as in the first etching process.

[0338] In addition, after exposing a part of the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R, a heat treatment may be further performed. The heat treatment can remove water contained in the organic compound layer and water adsorbed on the surface of the organic compound layer. The heat treatment may change the shape of the insulating layer 127. Specifically, the insulating layer 127 may extend to cover at least one of the ends of the inorganic insulating layer 125, the ends of the sacrificial layer 158B, the sacrificial layer 158G, and the sacrificial layer 158R, and the upper surfaces of the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R.

[0339] Note that FIG. 11(A) shows an example in which a portion of the end of the sacrificial layer 158G (specifically, the tapered portion formed by the first etching process) is covered by the insulating layer 127, and the tapered portion formed by the second etching process is exposed (see FIG. 4(A)).

[0340] The insulating layer 127 may cover the entire end of the sacrificial layer 158G. For example, the end of the insulating layer 127 may droop and cover the end of the sacrificial layer 158G. For example, the end of the insulating layer 127 may contact the upper surface of at least one of the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R.

[0341] 11B, a common electrode 155 is formed over the organic compound layer 103B, the organic compound layer 103G, the organic compound layer 103R, the conductive layer 152C, and the insulating layer 127. The common electrode 155 can be formed by a sputtering method, a vacuum deposition method, or the like. Alternatively, the common electrode 155 may be formed by stacking a film formed by a deposition method and a film formed by a sputtering method.

[0342] 11(C), the protective layer 131 is formed on the common electrode 155. The protective layer 131 can be formed by a method such as a vacuum deposition method, a sputtering method, a CVD method, or an ALD method.

[0343] Then, the substrate 120 is attached over the protective layer 131 by using the resin layer 122, so that a light-emitting device can be manufactured. As described above, in the method for manufacturing a light-emitting device according to one embodiment of the present invention, the insulating layer 156 is provided so as to have a region overlapping with a side surface of the conductive layer 151, and the conductive layer 152 is formed so as to cover the conductive layer 151 and the insulating layer 156. This can increase the yield of light-emitting devices and suppress the occurrence of defects.

[0344] As described above, in the manufacturing method of the light-emitting device according to one embodiment of the present invention, the island-shaped organic compound layer 103B, the island-shaped organic compound layer 103G, and the island-shaped organic compound layer 103R are formed by forming a film on one surface and then processing it, instead of using a fine metal mask, so that the island-shaped layers can be formed with a uniform thickness. As a result, a high-definition light-emitting device or a light-emitting device with a high aperture ratio can be realized. Even if the definition or aperture ratio is high and the distance between the subpixels is extremely short, the organic compound layer 103B, the organic compound layer 103G, and the organic compound layer 103R can be prevented from contacting each other in adjacent subpixels. Therefore, leakage current can be prevented from occurring between the subpixels. As a result, crosstalk can be prevented, and a light-emitting device with extremely high contrast can be realized. Even if a light-emitting device has a tandem light-emitting device manufactured by a photolithography method, a light-emitting device with good characteristics can be provided.

[0345] (Embodiment 4) In this embodiment, a light-emitting device of one embodiment of the present invention will be described with reference to FIGS.

[0346] [Pixel layout] In this embodiment, a pixel layout different from that in Fig. 3 will be mainly described. There is no particular limitation on the arrangement of the sub-pixels, and various methods can be applied. Examples of the arrangement of the sub-pixels include a stripe arrangement, an S-stripe arrangement, a matrix arrangement, a delta arrangement, a Bayer arrangement, and a pentile arrangement.

[0347] The top shape of the sub-pixels shown in the drawings in this embodiment mode corresponds to the top shape of the light-emitting region.

[0348] The top surface shape of the subpixel may be, for example, a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon, a polygon with rounded corners, an ellipse, or a circle.

[0349] Furthermore, the layout of the circuits constituting the subpixels is not limited to the range of the subpixels shown in the figures, and may be arranged outside of the subpixels.

[0350] An S-stripe arrangement is applied to the pixel 178 shown in Fig. 12(A) The pixel 178 shown in Fig. 12(A) is composed of three subpixels: a subpixel 110R, a subpixel 110G, and a subpixel 110B.

[0351] 12B shows a pixel 178 having a sub-pixel 110R with a substantially trapezoidal top surface shape with rounded corners, a sub-pixel 110G with a substantially triangular top surface shape with rounded corners, and a sub-pixel 110B with a substantially rectangular or hexagonal top surface shape with rounded corners. The sub-pixel 110R has a larger light-emitting area than the sub-pixel 110G. In this manner, the shape and size of each sub-pixel can be determined independently. For example, the more reliable the light-emitting device is, the smaller the size of the sub-pixel can be.

[0352] The Pentile array is applied to the pixels 124a and 124b shown in Fig. 12C. Fig. 12C shows an example in which the pixel 124a having the sub-pixel 110R and the sub-pixel 110G and the pixel 124b having the sub-pixel 110G and the sub-pixel 110B are arranged alternately.

[0353] The pixels 124a and 124b shown in Fig. 12(D) to Fig. 12(F) are arranged in a delta arrangement. The pixel 124a has two subpixels (subpixel 110R and subpixel 110G) in the upper row (first row) and one subpixel (subpixel 110B) in the lower row (second row). The pixel 124b has one subpixel (subpixel 110B) in the upper row (first row) and two subpixels (subpixel 110R and subpixel 110G) in the lower row (second row).

[0354] Figure 12(D) is an example in which each sub-pixel has an approximately rectangular top surface shape with rounded corners, Figure 12(E) is an example in which each sub-pixel has a circular top surface shape, and Figure 12(F) is an example in which each sub-pixel has an approximately hexagonal top surface shape with rounded corners.

[0355] In Fig. 12(F), each subpixel is arranged inside a close-packed hexagonal region. When focusing on one subpixel, each subpixel is arranged so that it is surrounded by six subpixels. In addition, subpixels that emit light of the same color are arranged so that they are not adjacent to each other. For example, when focusing on subpixel 110R, three subpixels 110G and three subpixels 110B are arranged alternately to surround subpixel 110R.

[0356] 12G shows an example in which subpixels of each color are arranged in a zigzag pattern. Specifically, when viewed from above, the positions of the upper sides of two subpixels arranged in a column direction (for example, subpixels 110R and 110G, or subpixels 110G and 110B) are misaligned.

[0357] 12(A) to 12(G), it is preferable that the subpixel 110R is the subpixel R that emits red light, the subpixel 110G is the subpixel G that emits green light, and the subpixel 110B is the subpixel B that emits blue light. Note that the configuration of the subpixels is not limited to this, and the colors that the subpixels emit and their order of arrangement can be determined appropriately. For example, the subpixel 110G may be the subpixel R that emits red light, and the subpixel 110R may be the subpixel G that emits green light.

[0358] In photolithography, the finer the pattern to be processed, the more the effect of light diffraction cannot be ignored, and therefore the fidelity is lost when the photomask pattern is transferred by exposure, making it difficult to process the resist mask into the desired shape. Therefore, even if the photomask pattern is rectangular, a pattern with rounded corners is likely to be formed. Therefore, the top surface shape of the subpixel may become a polygon with rounded corners, an ellipse, a circle, or the like.

[0359] Furthermore, in the manufacturing method of the light-emitting device according to one embodiment of the present invention, the organic compound layer is processed into an island shape using a resist mask. The resist film formed on the organic compound layer needs to be cured at a temperature lower than the heat resistance temperature of the organic compound layer. Therefore, depending on the heat resistance temperature of the material of the organic compound layer and the curing temperature of the resist material, the resist film may not be cured sufficiently. A resist film that is not cured sufficiently may have a shape different from a desired shape during processing. As a result, the top surface shape of the organic compound layer may be a polygon with rounded corners, an ellipse, a circle, or the like. For example, when a resist mask with a square top surface shape is formed, a resist mask with a circular top surface shape is formed, and the top surface shape of the organic compound layer may become circular.

[0360] In order to make the top surface shape of the organic compound layer into a desired shape, a technique for correcting a mask pattern in advance (OPC (Optical Proximity Correction) technique) may be used so that a design pattern and a transfer pattern coincide with each other. Specifically, in the OPC technique, a correction pattern is added to, for example, a figure corner portion on the mask pattern.

[0361] As shown in FIGS. 13A to 13I, a pixel can have four types of subpixels.

[0362] The pixels 178 shown in FIGS. 13(A) to 13(C) are arranged in a stripe.

[0363] Figure 13(A) is an example in which each subpixel has a rectangular top surface shape, Figure 13(B) is an example in which each subpixel has a top surface shape that is a combination of two semicircles and a rectangle, and Figure 13(C) is an example in which each subpixel has an elliptical top surface shape.

[0364] A matrix arrangement is applied to the pixels 178 shown in FIG. 13(D) to FIG. 13(F).

[0365] Figure 13(D) is an example where each sub-pixel has a square top surface shape, Figure 13(E) is an example where each sub-pixel has an approximately square top surface shape with rounded corners, and Figure 13(F) is an example where each sub-pixel has a circular top surface shape.

[0366] 13(G) and 13(H) show an example in which one pixel 178 is configured in two rows and three columns.

[0367] 13G has three subpixels (subpixel 110R, subpixel 110G, and subpixel 110B) in the top row (first row) and one subpixel (subpixel 110W) in the bottom row (second row). In other words, pixel 178 has subpixel 110R in the left column (first column), subpixel 110G in the center column (second column), subpixel 110B in the right column (third column), and subpixel 110W across these three columns.

[0368] The pixel 178 shown in FIG. 13(H) has three subpixels (subpixel 110R, subpixel 110G, and subpixel 110B) in the upper row (first row) and three subpixels 110W in the lower row (second row). In other words, the pixel 178 has the subpixels 110R and 110W in the left column (first column), the subpixels 110G and 110W in the center column (second column), and the subpixels 110B and 110W in the right column (third column). As shown in FIG. 13(H), by aligning the arrangement of the subpixels in the upper row and the lower row, it is possible to efficiently remove dust that may occur in the manufacturing process, for example. Therefore, a light emitting device with high display quality can be provided.

[0369] In the pixel 178 shown in FIGS. 13(G) and 13(H), the subpixels 110R, 110G, and 110B are arranged in a striped layout, thereby improving the display quality.

[0370] FIG. 13I shows an example in which one pixel 178 is arranged in three rows and two columns.

[0371] 13(I) has subpixel 110R in the top row (first row), subpixel 110G in the center row (second row), subpixel 110B from the first row to the second row, and one subpixel (subpixel 110W) in the bottom row (third row). In other words, pixel 178 has subpixel 110R and subpixel 110G in the left column (first column), subpixel 110B in the right column (second column), and subpixel 110W across these two columns.

[0372] In the pixel 178 shown in FIG. 13(I), the layout of the subpixels 110R, 110G, and 110B is a so-called S-stripe arrangement, which can improve the display quality.

[0373] 13A to 13I is composed of four subpixels, namely, subpixel 110R, subpixel 110G, subpixel 110B, and subpixel 110W. For example, subpixel 110R may be a subpixel that emits red light, subpixel 110G may be a subpixel that emits green light, subpixel 110B may be a subpixel that emits blue light, and subpixel 110W may be a subpixel that emits white light. At least one of subpixels 110R, subpixel 110G, subpixel 110B, and subpixel 110W may be a subpixel that emits cyan light, a subpixel that emits magenta light, a subpixel that emits yellow light, or a subpixel that emits near-infrared light.

[0374] As described above, in the light-emitting device of one embodiment of the present invention, various layouts can be applied to a pixel having a subpixel including a light-emitting device.

[0375] This embodiment mode can be combined with other embodiment modes or examples as appropriate. In addition, in the case where a plurality of configuration examples are shown in one embodiment mode in this specification, the configuration examples can be combined as appropriate.

[0376] (Embodiment 5) In this embodiment, a light-emitting device according to one embodiment of the present invention will be described.

[0377] The light emitting device of the present embodiment can be a high-definition light emitting device. Therefore, the light emitting device of the present embodiment can be used for the display unit of a wristwatch type, a bracelet type, or other information terminal (wearable device), and for the display unit of a wearable device that can be worn on the head, such as a head mounted display (HMD) or other VR device, and a glasses type AR device.

[0378] The light-emitting device of this embodiment can be a high-resolution light-emitting device or a large-sized light-emitting device. Therefore, the light-emitting device of this embodiment can be used for the display portion of, for example, a television device, a desktop or notebook personal computer, a monitor for a computer, digital signage, a large game machine such as a pachinko machine, and other electronic devices having a relatively large screen, as well as a digital camera, a digital video camera, a digital photo frame, a mobile phone, a portable game machine, a portable information terminal, and an audio reproducing device.

[0379] [Display module] 14A shows a perspective view of a display module 280. The display module 280 has a light emitting device 100A and an FPC 290. Note that the light emitting device included in the display module 280 is not limited to the light emitting device 100A, and may be either a light emitting device 100B or a light emitting device 100C described below.

[0380] The display module 280 has a substrate 291 and a substrate 292. The display module 280 has a display unit 281. The display unit 281 is a region that displays an image in the display module 280, and is a region where light from each pixel provided in a pixel unit 284 described later can be viewed.

[0381] 14(B) shows a perspective view that typically illustrates the configuration on the substrate 291 side. A circuit portion 282, a pixel circuit portion 283 on the circuit portion 282, and a pixel portion 284 on the pixel circuit portion 283 are stacked on the substrate 291. A terminal portion 285 for connecting to an FPC 290 is provided in a portion of the substrate 291 that does not overlap with the pixel portion 284. The terminal portion 285 and the circuit portion 282 are electrically connected by a wiring portion 286 that is composed of a plurality of wirings.

[0382] The pixel section 284 has a plurality of pixels 284a arranged periodically. An enlarged view of one pixel 284a is shown on the right side of Fig. 14(B). The various configurations described in the previous embodiment can be applied to the pixel 284a. Fig. 14(B) shows an example in which the pixel 284a has the same configuration as the pixel 178 shown in Fig. 3.

[0383] The pixel circuit section 283 has a plurality of pixel circuits 283a that are periodically arranged.

[0384] One pixel circuit 283a is a circuit that controls the driving of multiple elements included in one pixel 284a. One pixel circuit 283a can be configured to have three circuits that control the light emission of one light-emitting device. For example, the pixel circuit 283a can be configured to have at least one selection transistor, one current control transistor (drive transistor), and a capacitance for each light-emitting device. At this time, a gate signal is input to the gate of the selection transistor, and a video signal is input to the source or drain. This realizes an active matrix type light-emitting device.

[0385] The circuit portion 282 includes a circuit for driving each pixel circuit 283a of the pixel circuit portion 283. For example, it is preferable that the circuit portion 282 includes one or both of a gate line driver circuit and a source line driver circuit. In addition, the circuit portion 282 may include at least one of an arithmetic circuit, a memory circuit, a power supply circuit, and the like.

[0386] The FPC 290 functions as wiring for supplying a video signal, a power supply potential, or the like from the outside to the circuit portion 282. In addition, an IC may be mounted on the FPC 290.

[0387] The display module 280 can be configured such that one or both of the pixel circuit section 283 and the circuit section 282 are laminated under the pixel section 284, so that the aperture ratio (effective display area ratio) of the display section 281 can be extremely high. For example, the aperture ratio of the display section 281 can be set to 40% or more and less than 100%, preferably 50% or more and 95% or less, and more preferably 60% or more and 95% or less. In addition, the pixels 284a can be arranged at an extremely high density, so that the resolution of the display section 281 can be extremely high. For example, it is preferable that the pixels 284a are arranged in the display section 281 at a resolution of 2000 ppi or more, preferably 3000 ppi or more, more preferably 5000 ppi or more, and even more preferably 6000 ppi or more, and 20000 ppi or less, or 30000 ppi or less.

[0388] Such a display module 280 is extremely high-definition and can be suitably used in VR devices such as HMDs or glasses-type AR devices. For example, even in a configuration in which the display unit of the display module 280 is viewed through a lens, the display module 280 has an extremely high-definition display unit 281, so that even if the display unit is enlarged with a lens, pixels are not visible, and a highly immersive display can be performed. In addition, the display module 280 is not limited to this, and can be suitably used in electronic devices having a relatively small display unit. For example, it can be suitably used in the display unit of a wearable electronic device such as a wristwatch.

[0389] [Light-emitting device 100A] The light emitting device 100A shown in FIG. 15A includes a substrate 301, a light emitting device 130R, a light emitting device 130G, a light emitting device 130B, a capacitor 240, and a transistor 310. The light emitting device 100A shown in FIG.

[0390] The substrate 301 corresponds to the substrate 291 in FIGS. 14A and 14B. The transistor 310 is a transistor having a channel formation region in the substrate 301. As the substrate 301, for example, a semiconductor substrate such as a single crystal silicon substrate can be used. The transistor 310 includes a part of the substrate 301, a conductive layer 311, a low-resistance region 312, an insulating layer 313, and an insulating layer 314. The conductive layer 311 functions as a gate electrode. The insulating layer 313 is located between the substrate 301 and the conductive layer 311 and functions as a gate insulating layer. The low-resistance region 312 is a region in which the substrate 301 is doped with impurities, and functions as a source or drain. The insulating layer 314 is provided to cover a side surface of the conductive layer 311.

[0391] In addition, an element isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301 .

[0392] In addition, an insulating layer 261 is provided to cover the transistor 310 , and a capacitor 240 is provided on the insulating layer 261 .

[0393] Capacitor 240 has conductive layer 241, conductive layer 245, and insulating layer 243 located therebetween. Conductive layer 241 functions as one electrode of capacitor 240, conductive layer 245 functions as the other electrode of capacitor 240, and insulating layer 243 functions as a dielectric of capacitor 240.

[0394] The conductive layer 241 is provided over the insulating layer 261 and is embedded in the insulating layer 254. The conductive layer 241 is electrically connected to one of the source and the drain of the transistor 310 by a plug 271 embedded in the insulating layer 261. The insulating layer 243 is provided to cover the conductive layer 241. The conductive layer 245 is provided in a region overlapping with the conductive layer 241 with the insulating layer 243 interposed therebetween.

[0395] An insulating layer 255 is provided to cover the capacitor 240, an insulating layer 174 is provided on the insulating layer 255, and an insulating layer 175 is provided on the insulating layer 174. The light emitting device 130R, the light emitting device 130G, and the light emitting device 130B are provided on the insulating layer 175. FIG. 15(A) shows an example in which the light emitting device 130R, the light emitting device 130G, and the light emitting device 130B have the laminated structure shown in FIG. 1(A). An insulator is provided in the region between the adjacent light emitting devices. For example, in FIG. 15(A), an inorganic insulating layer 125 and an insulating layer 127 on the inorganic insulating layer 125 are provided in the region.

[0396] An insulating layer 156R is provided to have a region overlapping with a side surface of the conductive layer 151R of the light emitting device 130R, an insulating layer 156G is provided to have a region overlapping with a side surface of the conductive layer 151G of the light emitting device 130G, and an insulating layer 156B is provided to have a region overlapping with a side surface of the conductive layer 151B of the light emitting device 130B. Further, a conductive layer 152R is provided to cover the conductive layer 151R and the insulating layer 156R, a conductive layer 152G is provided to cover the conductive layer 151G and the insulating layer 156G, and a conductive layer 152B is provided to cover the conductive layer 151B and the insulating layer 156B. Furthermore, a sacrificial layer 158R is located on the organic compound layer 103R of the light-emitting device 130R, a sacrificial layer 158G is located on the organic compound layer 103G of the light-emitting device 130G, and a sacrificial layer 158B is located on the organic compound layer 103B of the light-emitting device 130B.

[0397] The conductive layer 151R, the conductive layer 151G, and the conductive layer 151B are electrically connected to one of the source or drain of the transistor 310 via the insulating layer 243, the insulating layer 255, the insulating layer 174, a plug 256 embedded in the insulating layer 175, the conductive layer 241 embedded in the insulating layer 254, and a plug 271 embedded in the insulating layer 261. The height of the top surface of the insulating layer 175 and the height of the top surface of the plug 256 are the same or approximately the same. Various conductive materials can be used for the plug.

[0398] Further, a protective layer 131 is provided on the light emitting devices 130R, 130G, and 130B. The substrate 120 is bonded onto the protective layer 131 by a resin layer 122. For details of the components from the light emitting devices 130 to the substrate 120, refer to the third embodiment. The substrate 120 corresponds to the substrate 292 in FIG. 14(A).

[0399] Fig. 15(B) is a modified example of the light emitting device 100A shown in Fig. 15(A). The light emitting device shown in Fig. 15(B) has a colored layer 132R, a colored layer 132G, and a colored layer 132B, and the light emitting device 130 has an area overlapping one of the colored layer 132R, the colored layer 132G, and the colored layer 132B. In the light emitting device shown in Fig. 15(B), the light emitting device 130 can emit, for example, white light. Also, for example, the colored layer 132R can transmit red light, the colored layer 132G can transmit green light, and the colored layer 132B can transmit blue light.

[0400] [Light-emitting device 100B] FIG. 16 shows a perspective view of light emitting device 100B, and FIG. 17(A) shows a cross-sectional view of light emitting device 100B.

[0401] Light emitting device 100B has a configuration in which substrate 352 and substrate 351 are bonded together. In Fig. 16, substrate 352 is indicated by a dashed line.

[0402] The light emitting device 100B has a pixel portion 177, a connection portion 140, a circuit 356, wiring 355, and the like. Fig. 16 shows an example in which an IC (integrated circuit) 354 and an FPC 353 are mounted on the light emitting device 100B. Therefore, the configuration shown in Fig. 16 can also be called a display module having the light emitting device 100B, an IC, and an FPC. Here, a light emitting device having a connector such as an FPC attached to a substrate, or a light emitting device having an IC mounted on the substrate, is called a display module.

[0403] The connection portion 140 is provided outside the pixel portion 177. The connection portion 140 can be provided along one side or multiple sides of the pixel portion 177. The connection portion 140 may be single or multiple. FIG. 16 shows an example in which the connection portion 140 is provided so as to surround the four sides of the pixel portion 177. The connection portion 140 electrically connects the common electrode of the light-emitting device and the conductive layer, and can supply a potential to the common electrode.

[0404] The circuit 356 can be, for example, a scanning line driver circuit.

[0405] The wiring 355 has a function of supplying signals and power to the pixel portion 177 and the circuit 356. The signals and power are input to the wiring 355 from the outside via the FPC 353 or from the IC 354.

[0406] 16 shows an example in which an IC 354 is provided on a substrate 351 by a chip on glass (COG) method or a chip on film (COF) method. For example, an IC having a scanning line driver circuit or a signal line driver circuit can be used as the IC 354. Note that the light emitting device 100B and the display module may not include an IC. Alternatively, the IC may be mounted on an FPC by a COF method.

[0407] FIG. 17(A) shows an example of a cross section of a light-emitting device 100B, in which a portion of a region including an FPC 353, a portion of a circuit 356, a portion of a pixel portion 177, a portion of a connection portion 140, and a portion of a region including an end portion are cut.

[0408] The light-emitting device 100B shown in Figure 17 (A) has, between a substrate 351 and a substrate 352, a transistor 201, a transistor 205, a light-emitting device 130R that emits red light, a light-emitting device 130G that emits green light, and a light-emitting device 130B that emits blue light, etc.

[0409] The light emitting device 130R, the light emitting device 130G, and the light emitting device 130B each have the laminated structure shown in Fig. 1A, except that the configuration of the pixel electrode is different. For details of the light emitting device, refer to the above embodiment.

[0410] Light-emitting device 130R has conductive layer 224R, conductive layer 151R on conductive layer 224R, and conductive layer 152R on conductive layer 151R. Light-emitting device 130G has conductive layer 224G, conductive layer 151G on conductive layer 224G, and conductive layer 152G on conductive layer 151G. Light-emitting device 130B has conductive layer 224B, conductive layer 151B on conductive layer 224B, and conductive layer 152B on conductive layer 151B. Here, conductive layer 224R, conductive layer 151R, and conductive layer 152R may be collectively referred to as a pixel electrode of light-emitting device 130R, and conductive layer 151R and conductive layer 152R excluding conductive layer 224R may be referred to as a pixel electrode of light-emitting device 130R. Similarly, conductive layer 224G, conductive layer 151G, and conductive layer 152G may be collectively referred to as a pixel electrode of light-emitting device 130G, and conductive layer 151G and conductive layer 152G excluding conductive layer 224G may be collectively referred to as a pixel electrode of light-emitting device 130G. Also, conductive layer 224B, conductive layer 151B, and conductive layer 152B may be collectively referred to as a pixel electrode of light-emitting device 130B, and conductive layer 151B and conductive layer 152B excluding conductive layer 224B may be collectively referred to as a pixel electrode of light-emitting device 130B.

[0411] The conductive layer 224R is connected to the conductive layer 222b of the transistor 205 through an opening provided in the insulating layer 214. An end of the conductive layer 151R is located outside an end of the conductive layer 224R. An insulating layer 156R is provided to have a region in contact with a side surface of the conductive layer 151R, and a conductive layer 152R is provided to cover the conductive layer 151R and the insulating layer 156R.

[0412] Conductive layer 224G, conductive layer 151G, conductive layer 152G, and insulating layer 156G in light-emitting device 130G, and conductive layer 224B, conductive layer 151B, conductive layer 152B, and insulating layer 156B in light-emitting device 130B are similar to conductive layer 224R, conductive layer 151R, conductive layer 152R, and insulating layer 156R in light-emitting device 130R, and therefore detailed description thereof will be omitted.

[0413] Recesses are formed in the conductive layers 224R, 224G, and 224B so as to cover the openings provided in the insulating layer 214. The layer 128 is embedded in the recesses.

[0414] The layer 128 has a function of planarizing the recesses of the conductive layer 224R, the conductive layer 224G, and the conductive layer 224B. The conductive layer 151R, the conductive layer 151G, and the conductive layer 151B, which are electrically connected to the conductive layer 224R, the conductive layer 224G, and the conductive layer 224B, are provided on the conductive layer 224R, the conductive layer 224G, and the conductive layer 224B, and the layer 128. Therefore, the regions overlapping with the recesses of the conductive layer 224R, the conductive layer 224G, and the conductive layer 224B can also be used as light-emitting regions, and the aperture ratio of the pixel can be increased.

[0415] The layer 128 may be an insulating layer or a conductive layer. Various inorganic insulating materials, organic insulating materials, and conductive materials can be appropriately used for the layer 128. In particular, the layer 128 is preferably formed using an insulating material, and more preferably formed using an organic insulating material. For example, the organic insulating material that can be used for the insulating layer 127 described above can be used for the layer 128.

[0416] A protective layer 131 is provided on the light emitting device 130R, the light emitting device 130G, and the light emitting device 130B. The protective layer 131 and the substrate 352 are bonded via an adhesive layer 142. The substrate 352 is provided with a light shielding layer 157. A solid sealing structure, a hollow sealing structure, or the like can be applied to seal the light emitting device 130. In FIG. 17(A), the space between the substrate 352 and the substrate 351 is filled with the adhesive layer 142, and a solid sealing structure is applied. Alternatively, the space may be filled with an inert gas (nitrogen, argon, or the like), and a hollow sealing structure may be applied. In this case, the adhesive layer 142 may be provided so as not to overlap with the light emitting device. The space may also be filled with a resin different from the adhesive layer 142 provided in a frame shape.

[0417] 17(A) shows an example in which the connection portion 140 has a conductive layer 224C obtained by processing the same conductive film as the conductive layers 224R, 224G, and 224B, a conductive layer 151C obtained by processing the same conductive film as the conductive layers 151R, 151G, and 151B, and a conductive layer 152C obtained by processing the same conductive film as the conductive layers 152R, 152G, and 152B. Also, FIG. 17(A) shows an example in which an insulating layer 156C is provided so as to have an area overlapping with a side surface of the conductive layer 151C.

[0418] The light emitting device 100B is a top emission type. Light emitted by the light emitting device is emitted to the substrate 352 side. The substrate 352 is preferably made of a material that is highly transparent to visible light. The pixel electrode contains a material that reflects visible light, and the counter electrode (common electrode 155) contains a material that transmits visible light.

[0419] Both the transistor 201 and the transistor 205 are formed over a substrate 351. These transistors can be manufactured using the same material and through the same process.

[0420] An insulating layer 211, an insulating layer 213, an insulating layer 215, and an insulating layer 214 are provided over a substrate 351 in this order. A part of the insulating layer 211 functions as a gate insulating layer for each transistor. A part of the insulating layer 213 functions as a gate insulating layer for each transistor. The insulating layer 215 is provided to cover the transistors. The insulating layer 214 is provided to cover the transistors and functions as a planarizing layer. Note that the number of gate insulating layers and the number of insulating layers covering the transistors are not limited, and each may be a single layer or two or more layers.

[0421] At least one of the insulating layers covering the transistor is preferably made of a material that is difficult for impurities such as water and hydrogen to diffuse into. This allows the insulating layer to function as a barrier layer. With this structure, it is possible to effectively prevent impurities from diffusing into the transistor from the outside, thereby improving the reliability of the light-emitting device.

[0422] It is preferable to use an inorganic insulating film for each of the insulating layers 211, 213, and 215. As the inorganic insulating film, for example, a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, or an aluminum nitride film can be used. A hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, a neodymium oxide film, or the like may also be used. Two or more of the above insulating films may also be stacked.

[0423] An organic insulating layer is suitable for the insulating layer 214 that functions as a planarizing layer. Examples of materials that can be used for the organic insulating layer include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins. The insulating layer 214 may also have a laminated structure of an organic insulating layer and an inorganic insulating layer. The outermost layer of the insulating layer 214 preferably has a function as an etching protection layer. This can prevent a recess from being formed in the insulating layer 214 when the conductive layer 224R, the conductive layer 151R, the conductive layer 152R, or the like is processed. Alternatively, a recess may be provided in the insulating layer 214 when the conductive layer 224R, the conductive layer 151R, the conductive layer 152R, or the like is processed.

[0424] The transistor 201 and the transistor 205 each have a conductive layer 221 functioning as a gate, an insulating layer 211 functioning as a gate insulating layer, a conductive layer 222a and a conductive layer 222b functioning as a source and a drain, a semiconductor layer 231, an insulating layer 213 functioning as a gate insulating layer, and a conductive layer 223 functioning as a gate. Here, the same hatched pattern is applied to a plurality of layers obtained by processing the same conductive film. The insulating layer 211 is located between the conductive layer 221 and the semiconductor layer 231. The insulating layer 213 is located between the conductive layer 223 and the semiconductor layer 231.

[0425] The structure of the transistor included in the light-emitting device of this embodiment is not particularly limited. For example, a planar transistor, a staggered transistor, an inverted staggered transistor, or the like can be used. In addition, either a top-gate type or a bottom-gate type transistor structure may be used. Alternatively, gates may be provided above and below a semiconductor layer in which a channel is formed.

[0426] The transistor 201 and the transistor 205 have a structure in which a semiconductor layer in which a channel is formed is sandwiched between two gates. The two gates may be connected and supplied with the same signal to drive the transistor. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential for controlling the threshold voltage to one of the two gates and applying a potential for driving to the other.

[0427] The crystallinity of a semiconductor material used for a transistor is not particularly limited, and any of an amorphous semiconductor and a crystalline semiconductor (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a semiconductor having a crystalline region in a part) may be used. The use of a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0428] A semiconductor layer of the transistor preferably contains a metal oxide, that is, the light-emitting device of this embodiment preferably uses a transistor in which a channel formation region is formed using a metal oxide (hereinafter, referred to as an OS transistor).

[0429] Examples of oxide semiconductors having crystallinity include c-axis-aligned crystalline (CAAC)-OS and nanocrystalline (nc)-OS.

[0430] Alternatively, a transistor using silicon in a channel formation region (Si transistor) may be used. Examples of silicon include single crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, a transistor having low temperature polysilicon (LTPS (Low Temperature Poly Silicon)) in a semiconductor layer (hereinafter, also referred to as an LTPS transistor) may be used. An LTPS transistor has high field effect mobility and good frequency characteristics.

[0431] By using Si transistors such as LTPS transistors, circuits that need to be driven at high frequencies (such as source driver circuits) can be built on the same substrate as the display unit, simplifying the external circuits mounted on the light-emitting device and reducing component and mounting costs.

[0432] An OS transistor has a much higher field-effect mobility than a transistor using amorphous silicon. In addition, the OS transistor has a significantly smaller source-drain leakage current in an off state (hereinafter also referred to as off current) and can hold charge accumulated in a capacitor connected in series with the transistor for a long period of time. In addition, the use of an OS transistor can reduce the power consumption of a light-emitting device.

[0433] Furthermore, in order to increase the emission luminance of a light-emitting device included in a pixel circuit, it is necessary to increase the amount of current flowing through the light-emitting device. To achieve this, it is necessary to increase the source-drain voltage of a drive transistor included in the pixel circuit. Since an OS transistor has a higher withstand voltage between the source and drain compared to a Si transistor, a high voltage can be applied between the source and drain of the OS transistor. Therefore, by using an OS transistor as the drive transistor included in a pixel circuit, it is possible to increase the amount of current flowing through the light-emitting device and increase the emission luminance of the light-emitting device.

[0434] Furthermore, in terms of the saturation characteristics of the current that flows when the transistor operates in the saturation region, the OS transistor can pass a more stable current (saturation current) than a Si transistor, even when the source-drain voltage gradually increases. For this reason, by using an OS transistor as a drive transistor, for example, a stable current can be passed through a light-emitting device even when the current-voltage characteristics of the light-emitting device vary. In other words, when the OS transistor operates in the saturation region, the source-drain current hardly changes even when the source-drain voltage is increased, so the light emission luminance of the light-emitting device can be stabilized.

[0435] As described above, by using an OS transistor for a driving transistor included in a pixel circuit, it is possible to achieve "suppression of black floating," "increase in light emission luminance," "multiple gradations," and "suppression of variation in light-emitting devices," etc.

[0436] The semiconductor layer preferably contains, for example, indium, M (M is one or more selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more selected from aluminum, gallium, yttrium, and tin.

[0437] In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also referred to as IGZO) as the semiconductor layer. Alternatively, it is preferable to use an oxide containing indium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium, gallium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), and zinc (Zn) (also referred to as IAZO). Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), gallium (Ga), and zinc (Zn) (also referred to as IAGZO).

[0438] When the semiconductor layer is an In-M-Zn oxide, the atomic ratio of In in the In-M-Zn oxide is preferably equal to or greater than the atomic ratio of M. Examples of atomic ratios of metal elements in such In-M-Zn oxides include In:M:Zn=1:1:1 or a composition thereabout, In:M:Zn=1:1:1.2 or a composition thereabout, In:M:Zn=2:1:3 or a composition thereabout, In:M:Zn=3:1:2 or a composition thereabout, In:M:Zn=4:2:3 or a composition thereabout, In:M:Zn=4:2:4.1 or a composition thereabout, In:M:Zn=5:1:3 or a composition thereabout, In:M:Zn=5:1:6 or a composition thereabout, In:M:Zn=5:1:7 or a composition thereabout, In:M:Zn=5:1:8 or a composition thereabout, In:M:Zn=6:1:6 or a composition thereabout, and In:M:Zn=5:2:5 or a composition thereabout. The term "nearby composition" includes a range of ±30% of the desired atomic ratio.

[0439] For example, when describing a composition having an atomic ratio of In:Ga:Zn=4:2:3 or thereabout, it includes a case where, when the atomic ratio of In is 4, the atomic ratio of Ga is 1 or more and 3 or less, and the atomic ratio of Zn is 2 or more and 4 or less. When describing a composition having an atomic ratio of In:Ga:Zn=5:1:6 or thereabout, it includes a case where, when the atomic ratio of In is 5, the atomic ratio of Ga is more than 0.1 and 2 or less, and the atomic ratio of Zn is 5 or more and 7 or less. When describing a composition having an atomic ratio of In:Ga:Zn=1:1:1 or thereabout, it includes a case where, when the atomic ratio of In is 1, the atomic ratio of Ga is more than 0.1 and 2 or less, and the atomic ratio of Zn is more than 0.1 and 2 or less.

[0440] The transistors included in the circuit 356 and the transistors included in the pixel portion 177 may have the same structure or different structures. The transistors included in the circuit 356 may all have the same structure or may have two or more types. Similarly, the transistors included in the pixel portion 177 may all have the same structure or may have two or more types.

[0441] All the transistors in the pixel portion 177 may be OS transistors, all the transistors in the pixel portion 177 may be Si transistors, or some of the transistors in the pixel portion 177 may be OS transistors and the rest may be Si transistors.

[0442] For example, by using both an LTPS transistor and an OS transistor in the pixel portion 177, a light-emitting device with low power consumption and high driving capability can be realized. A configuration in which an LTPS transistor and an OS transistor are combined may be referred to as LTPO. Note that, for example, it is preferable to use an OS transistor as a transistor that functions as a switch for controlling the conduction / non-conduction of wiring, and to use an LTPS transistor as a transistor for controlling current.

[0443] For example, one of the transistors in the pixel section 177 functions as a transistor for controlling a current flowing through a light-emitting device, and can be called a driving transistor. One of the source and drain of the driving transistor is electrically connected to a pixel electrode of the light-emitting device. It is preferable to use an LTPS transistor for the driving transistor. This allows the current flowing through the light-emitting device in the pixel circuit to be increased.

[0444] On the other hand, the other one of the transistors in the pixel portion 177 functions as a switch for controlling selection / non-selection of the pixel, and can also be called a selection transistor. The gate of the selection transistor is electrically connected to a gate line, and one of the source and drain is electrically connected to a source line (signal line). It is preferable to use an OS transistor for the selection transistor. This allows the gradation of the pixel to be maintained even if the frame frequency is significantly reduced (for example, 1 fps or less), so that power consumption can be reduced by stopping the driver when displaying a still image.

[0445] As described above, the light-emitting device of one embodiment of the present invention can have a high aperture ratio, high definition, high display quality, and low power consumption.

[0446] Note that the light-emitting device of one embodiment of the present invention has an OS transistor and a light-emitting device with an MML (metal maskless) structure. With this structure, leakage current that may flow through the transistor and leakage current that may flow between adjacent light-emitting devices (also referred to as lateral leakage current, horizontal leakage current, or lateral leakage current) can be extremely low. With the above structure, when an image is displayed on the light-emitting device, a viewer can observe one or more of image sharpness, image sharpness, high saturation, and high contrast ratio. Note that with a structure in which leakage current that may flow through the transistor and horizontal leakage current between the light-emitting devices are extremely low, light leakage that may occur during black display (so-called black floating) can be extremely low.

[0447] In particular, among light-emitting devices with an MML structure, by applying the SBS (Side By Side) structure, which is a structure in which the light-emitting layers are made differently or painted differently as described above, the layers provided between the light-emitting devices (for example, organic layers shared between the light-emitting devices, also called common layers) are configured to be separated, making it possible to eliminate or greatly reduce side leakage.

[0448] 17B and 17C show other structural examples of the transistor.

[0449] The transistor 209 and the transistor 210 each include a conductive layer 221 functioning as a gate, an insulating layer 211 functioning as a gate insulating layer, a semiconductor layer 231 having a channel formation region 231i and a pair of low-resistance regions 231n, a conductive layer 222a connected to one of the pair of low-resistance regions 231n, a conductive layer 222b connected to the other of the pair of low-resistance regions 231n, an insulating layer 225 functioning as a gate insulating layer, a conductive layer 223 functioning as a gate, and an insulating layer 215 covering the conductive layer 223. The insulating layer 211 is located between the conductive layer 221 and the channel formation region 231i. The insulating layer 225 is located at least between the conductive layer 223 and the channel formation region 231i. Furthermore, an insulating layer 218 covering the transistor may be provided.

[0450] 17B shows an example in which the insulating layer 225 covers the top surface and side surfaces of the semiconductor layer 231. The conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings provided in the insulating layer 225 and the insulating layer 215, respectively. One of the conductive layer 222a and the conductive layer 222b functions as a source, and the other functions as a drain.

[0451] 17C, the insulating layer 225 overlaps with the channel formation region 231i of the semiconductor layer 231, but does not overlap with the low-resistance region 231n. For example, the insulating layer 225 is processed using the conductive layer 223 as a mask, so that the structure shown in FIG. 17C can be manufactured. In FIG. 17C, the insulating layer 215 is provided to cover the insulating layer 225 and the conductive layer 223, and the conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings in the insulating layer 215.

[0452] A connection portion 204 is provided in an area of ​​the substrate 351 where the substrate 352 does not overlap. In the connection portion 204, the wiring 355 is electrically connected to the FPC 353 via the conductive layer 166 and the connection layer 242. The conductive layer 166 is an example of a laminated structure of a conductive film obtained by processing the same conductive film as the conductive layers 224R, 224G, and 224B, a conductive film obtained by processing the same conductive film as the conductive layers 151R, 151G, and 151B, and a conductive film obtained by processing the same conductive film as the conductive layers 152R, 152G, and 152B. On the upper surface of the connection portion 204, the conductive layer 166 is exposed. This allows the connection portion 204 and the FPC 353 to be electrically connected via the connection layer 242.

[0453] It is preferable to provide a light-shielding layer 157 on the surface of the substrate 352 facing the substrate 351. The light-shielding layer 157 can be provided between adjacent light-emitting devices, on the connection portion 140, on the circuit 356, etc. In addition, various optical members can be disposed on the outside of the substrate 352.

[0454] The materials usable for the substrate 120 can be used for the substrate 351 and the substrate 352, respectively.

[0455] The adhesive layer 142 may be made of a material that can be used for the resin layer 122 .

[0456] The connection layer 242 may be an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0457] [Light emitting device 100H] A light emitting device 100H shown in FIG. 18 differs from light emitting device 100B shown in FIG. 17(A) mainly in that the light emitting device 100H is a bottom emission type light emitting device.

[0458] Light emitted by the light emitting device is emitted to the side of the substrate 351. It is preferable that a material having high transparency to visible light is used for the substrate 351. On the other hand, the light transmissivity of a material used for the substrate 352 does not matter.

[0459] It is preferable to form a light-shielding layer 157 between the substrate 351 and the transistor 201 and between the substrate 351 and the transistor 205. Fig. 18 shows an example in which the light-shielding layer 157 is provided over the substrate 351, the insulating layer 153 is provided over the light-shielding layer 157, and the transistors 201, 205, etc. are provided over the insulating layer 153.

[0460] Light emitting device 130R includes a conductive layer 112R, a conductive layer 126R on conductive layer 112R, and a conductive layer 129R on conductive layer 126R.

[0461] Light emitting device 130B has conductive layer 112B, conductive layer 126B on conductive layer 112B, and conductive layer 129B on conductive layer 126B.

[0462] The conductive layers 112R, 112B, 126R, 126B, 129R, and 129B are made of a material that is highly transparent to visible light. The common electrode 155 is preferably made of a material that reflects visible light.

[0463] Although the light emitting device 130G is not shown in FIG. 18, the light emitting device 130G is also provided.

[0464] In addition, although FIG. 18 and other figures show an example in which the upper surface of layer 128 has a flat portion, the shape of layer 128 is not particularly limited.

[0465] [Light-emitting device 100C] The light emitting device 100C shown in FIG. 19(A) is a modification of the light emitting device 100B shown in FIG. 17(A), and differs from the light emitting device 100B mainly in that it has colored layers 132R, 132G, and 132B.

[0466] In the light emitting device 100C, the light emitting device 130 has an area overlapping one of the colored layer 132R, the colored layer 132G, and the colored layer 132B. The colored layer 132R, the colored layer 132G, and the colored layer 132B can be provided on the surface of the substrate 352 facing the substrate 351. An end of the colored layer 132R, an end of the colored layer 132G, and an end of the colored layer 132B can overlap the light blocking layer 157.

[0467] In the light emitting device 100C, the light emitting device 130 can emit, for example, white light. For example, the colored layer 132R can transmit red light, the colored layer 132G can transmit green light, and the colored layer 132B can transmit blue light. The light emitting device 100C may be configured such that the colored layers 132R, 132G, and 132B are provided between the protective layer 131 and the adhesive layer 142.

[0468] 17A, 19A, and the like show examples in which the top surface of the layer 128 has a flat portion, but there is no particular limitation on the shape of the layer 128. Modified examples of the layer 128 are shown in FIGS.

[0469] 19(B) and 19(D), the upper surface of layer 128 may have a shape with a recess in the center and its vicinity in cross-sectional view, that is, a shape with a concave curved surface. In addition, common layer 154 may be provided so as to contact common electrode 155.

[0470] Also, as shown in FIG. 19(C), the upper surface of layer 128 may be configured so that the center and its vicinity bulge in cross section, that is, have a convex curved shape.

[0471] The upper surface of layer 128 may have one or both of a convex curved surface and a concave curved surface. The number of convex curved surfaces and concave curved surfaces that the upper surface of layer 128 has is not limited, and may be one or more.

[0472] Furthermore, the height of the upper surface of layer 128 and the height of the upper surface of conductive layer 224R may be the same or approximately the same, or may be different from each other. For example, the height of the upper surface of layer 128 may be lower or higher than the height of the upper surface of conductive layer 224R.

[0473] 19(B) can also be said to be an example in which layer 128 is contained inside a recess formed in conductive layer 224R. On the other hand, as shown in FIG. 19(D), layer 128 may be present outside a recess formed in conductive layer 224R, that is, the width of the upper surface of layer 128 may be wider than the recess.

[0474] This embodiment mode can be combined with other embodiment modes or examples as appropriate. In addition, in the case where a plurality of configuration examples are shown in one embodiment mode in this specification, the configuration examples can be combined as appropriate.

[0475] (Embodiment 6) In this embodiment, an electronic device according to one embodiment of the present invention will be described.

[0476] The electronic devices of this embodiment include the light-emitting device of one embodiment of the present invention in a display portion. The light-emitting device of one embodiment of the present invention is highly reliable and can easily achieve high definition and high resolution. Therefore, the light-emitting device of one embodiment of the present invention can be used in the display portion of various electronic devices.

[0477] Examples of electronic devices include electronic devices with relatively large screens, such as television devices, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and audio playback devices.

[0478] In particular, the light-emitting device of one embodiment of the present invention can be suitably used in electronic devices having a relatively small display area because it can increase the resolution. Examples of such electronic devices include wristwatch-type and bracelet-type information terminals (wearable devices), as well as head-mounted wearable devices such as VR devices such as head-mounted displays, glasses-type AR devices, and MR devices.

[0479] The light-emitting device of one embodiment of the present invention preferably has an extremely high resolution such as HD (1280×720 pixels), FHD (1920×1080 pixels), WQHD (2560×1440 pixels), WQXGA (2560×1600 pixels), 4K (3840×2160 pixels), or 8K (7680×4320 pixels). In particular, a resolution of 4K, 8K, or more is preferable. The pixel density (definition) of the light-emitting device of one embodiment of the present invention is preferably 100 ppi or more, more preferably 300 ppi or more, more preferably 500 ppi or more, more preferably 1000 ppi or more, more preferably 2000 ppi or more, more preferably 3000 ppi or more, more preferably 5000 ppi or more, and even more preferably 7000 ppi or more. By using a light-emitting device having either or both of high resolution and high definition, it is possible to further improve the sense of realism and depth in electronic devices for personal use such as portable or home use. In addition, the screen ratio (aspect ratio) of the light-emitting device according to one embodiment of the present invention is not particularly limited. For example, the light-emitting device can support various screen ratios such as 1:1 (square), 4:3, 16:9, and 16:10.

[0480] The electronic device of this embodiment may have a sensor (including a function of measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays).

[0481] The electronic device of the present embodiment can have various functions, such as a function of displaying various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function of displaying a calendar, date, time, etc., a function of executing various software (programs), a wireless communication function, a function of reading out a program or data recorded on a recording medium, etc.

[0482] An example of a wearable device that can be worn on the head will be described with reference to Figures 20(A) to 20(D). These wearable devices have at least one of the following functions: a function to display AR content, a function to display VR content, a function to display SR content, and a function to display MR content. By having an electronic device have the function to display at least one of AR, VR, SR, and MR content, it is possible to enhance the user's sense of immersion.

[0483] Electronic device 700A shown in FIG. 20(A) and electronic device 700B shown in FIG. 20(B) each have a pair of display panels 751, a pair of housings 721, a communication unit (not shown), a pair of mounting units 723, a control unit (not shown), an imaging unit (not shown), a pair of optical members 753, a frame 757, and a pair of nose pads 758.

[0484] The light-emitting device of one embodiment of the present invention can be applied to the display panel 751. Thus, the electronic device can be highly reliable.

[0485] Each of the electronic devices 700A and 700B can project an image displayed on the display panel 751 onto a display area 756 of the optical member 753. Since the optical member 753 is translucent, the user can see the image displayed in the display area superimposed on a transmitted image visually recognized through the optical member 753. Therefore, each of the electronic devices 700A and 700B is an electronic device capable of AR display.

[0486] The electronic device 700A and the electronic device 700B may be provided with a camera capable of capturing an image of the front as an imaging unit. In addition, the electronic device 700A and the electronic device 700B may each be provided with an acceleration sensor such as a gyro sensor, thereby detecting the orientation of the user's head and displaying an image corresponding to the orientation in the display area 756.

[0487] The communication unit has a wireless communication device and can supply, for example, a video signal through the wireless communication device. Note that instead of or in addition to the wireless communication device, a connector to which a cable through which a video signal and a power supply potential can be connected may be provided.

[0488] Furthermore, the electronic device 700A and the electronic device 700B are provided with a battery, which can be charged wirelessly and / or wired.

[0489] The housing 721 may be provided with a touch sensor module. The touch sensor module has a function of detecting that the outer surface of the housing 721 is touched. The touch sensor module detects a tap operation, a slide operation, or the like by the user, and can execute various processes. For example, a tap operation can execute a process such as pausing or resuming a video, and a slide operation can execute a process such as fast forwarding or rewinding. Furthermore, by providing a touch sensor module in each of the two housings 721, the range of operations can be expanded.

[0490] As the touch sensor module, various touch sensors can be applied. For example, various types of sensors can be adopted, such as a capacitance type, a resistive film type, an infrared type, an electromagnetic induction type, a surface acoustic wave type, or an optical type. In particular, it is preferable to apply a capacitance type or an optical type sensor to the touch sensor module.

[0491] When an optical touch sensor is used, a photoelectric conversion device (also called a photoelectric conversion element) can be used as the light receiving element. The active layer of the photoelectric conversion device can be made of either or both of an inorganic semiconductor and an organic semiconductor.

[0492] Electronic device 800A shown in Figure 20 (C) and electronic device 800B shown in Figure 20 (D) each have a pair of display units 820, a housing 821, a communication unit 822, a pair of mounting units 823, a control unit 824, a pair of imaging units 825, and a pair of lenses 832.

[0493] A light-emitting device according to one embodiment of the present invention can be applied to the display portion 820. Thus, the electronic device can be highly reliable.

[0494] Display unit 820 is provided inside housing 821 at a position that can be viewed through lens 832. Also, by displaying different images on the pair of display units 820, it is possible to perform three-dimensional display using parallax.

[0495] The electronic device 800A and the electronic device 800B can each be said to be electronic devices for VR. A user wearing the electronic device 800A or the electronic device 800B can view an image displayed on the display unit 820 through the lens 832.

[0496] It is preferable that electronic device 800A and electronic device 800B each have a mechanism capable of adjusting the left-right positions of lens 832 and display unit 820 so that they are optimally positioned according to the position of the user's eyes. It is also preferable that electronic device 800A and electronic device 800B each have a mechanism for adjusting the focus by changing the distance between lens 832 and display unit 820.

[0497] The mounting unit 823 allows the user to mount the electronic device 800A or the electronic device 800B on the head. For example, in Fig. 20(C), the mounting unit 823 is shaped like a pair of glasses (also called a joint or temple), but is not limited thereto. The mounting unit 823 may be shaped like a helmet or band, for example, as long as it can be worn by the user.

[0498] The imaging unit 825 has a function of acquiring external information. Data acquired by the imaging unit 825 can be output to the display unit 820. An image sensor can be used for the imaging unit 825. In addition, multiple cameras may be provided so as to be compatible with multiple angles of view, such as telephoto and wide angle.

[0499] Although an example having the imaging unit 825 is shown here, a distance measuring sensor (hereinafter also referred to as a detection unit) capable of measuring the distance to an object may be provided. That is, the imaging unit 825 is one aspect of the detection unit. As the detection unit, for example, an image sensor or a distance image sensor such as a LIDAR (Light Detection and Ranging) can be used. By using an image obtained by the camera and an image obtained by the distance image sensor, more information can be obtained, enabling more accurate gesture operation.

[0500] The electronic device 800A may have a vibration mechanism that functions as a bone conduction earphone. For example, a configuration having the vibration mechanism can be applied to one or more of the display unit 820, the housing 821, and the wearing unit 823. This makes it possible to enjoy video and audio by simply wearing the electronic device 800A without requiring a separate audio device such as headphones, earphones, or speakers.

[0501] The electronic device 800A and the electronic device 800B may each have an input terminal. The input terminal can be connected to a cable for supplying a video signal from a video output device or the like and power for charging a battery provided in the electronic device.

[0502] The electronic device of one embodiment of the present invention may have a function of wireless communication with the earphone 750. The earphone 750 has a communication unit (not shown) and has a wireless communication function. The earphone 750 can receive information (e.g., audio data) from the electronic device through the wireless communication function. For example, the electronic device 700A shown in FIG. 20A has a function of transmitting information to the earphone 750 through the wireless communication function. For example, the electronic device 800A shown in FIG. 20C has a function of transmitting information to the earphone 750 through the wireless communication function.

[0503] The electronic device may also have an earphone unit. Electronic device 700B shown in Fig. 20(B) has earphone unit 727. For example, earphone unit 727 and a control unit may be configured to be connected to each other by wire. A part of the wiring connecting earphone unit 727 and the control unit may be disposed inside housing 721 or mounting unit 723.

[0504] Similarly, electronic device 800B shown in Fig. 20(D) has earphone unit 827. For example, earphone unit 827 and control unit 824 can be configured to be connected to each other by wire. A part of the wiring connecting earphone unit 827 and control unit 824 may be disposed inside housing 821 or wearing unit 823. In addition, earphone unit 827 and wearing unit 823 may have a magnet. This allows earphone unit 827 to be fixed to wearing unit 823 by magnetic force, which is preferable as it makes storage easier.

[0505] The electronic device may have an audio output terminal to which earphones or headphones can be connected. The electronic device may have one or both of an audio input terminal and an audio input mechanism. For example, a sound collector such as a microphone can be used as the audio input mechanism. The electronic device may have a function as a so-called headset by having the audio input mechanism.

[0506] As described above, as electronic devices according to one embodiment of the present invention, both glasses-type devices (such as the electronic device 700A and the electronic device 700B) and goggles-type devices (such as the electronic device 800A and the electronic device 800B) are suitable.

[0507] Furthermore, the electronic device according to one embodiment of the present invention can transmit information to the earphones in a wired or wireless manner.

[0508] An electronic device 6500 shown in FIG. 21A is a portable information terminal that can be used as a smartphone.

[0509] The electronic device 6500 includes a housing 6501, a display portion 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, and a light source 6508. The display portion 6502 has a touch panel function.

[0510] The light-emitting device of one embodiment of the present invention can be applied to the display portion 6502. Therefore, the electronic device can be highly reliable.

[0511] FIG. 21B is a schematic cross-sectional view including the end portion of the housing 6501 on the microphone 6506 side.

[0512] A light-transmitting protective member 6510 is provided on the display surface side of the housing 6501, and a display panel 6511, optical members 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are arranged in the space surrounded by the housing 6501 and the protective member 6510.

[0513] A display panel 6511, an optical member 6512, and a touch sensor panel 6513 are fixed to the protective member 6510 by an adhesive layer (not shown).

[0514] In an area outside the display unit 6502, a part of the display panel 6511 is folded back, and the folded back part is connected to an FPC 6515. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to a terminal provided on a printed circuit board 6517.

[0515] The light-emitting device of one embodiment of the present invention can be applied to the display panel 6511. Therefore, an extremely lightweight electronic device can be realized. In addition, since the display panel 6511 is extremely thin, a large-capacity battery 6518 can be mounted thereon while keeping the thickness of the electronic device small. In addition, by folding back a part of the display panel 6511 and arranging a connection portion with the FPC 6515 on the back side of the pixel portion, an electronic device with a narrow frame can be realized.

[0516] 21C shows an example of a television set. In a television set 7100, a display portion 7000 is incorporated in a housing 7171. Here, the housing 7171 is supported by a stand 7173.

[0517] The light-emitting device of one embodiment of the present invention can be applied to the display portion 7000. Therefore, the electronic device can be provided with high reliability.

[0518] 21C can be operated using an operation switch provided on the housing 7171 and a separate remote control 7151. Alternatively, the display portion 7000 may be provided with a touch sensor, and the television set 7100 may be operated by touching the display portion 7000 with a finger or the like. The remote control 7151 may have a display portion that displays information output from the remote control 7151. The channel and volume can be operated by using an operation key or a touch panel provided on the remote control 7151, and an image displayed on the display portion 7000 can be controlled.

[0519] The television device 7100 includes a receiver, a modem, and the like. The receiver can receive general television broadcasts. Also, by connecting to a wired or wireless communication network via a modem, it is possible to perform one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication.

[0520] 21D shows an example of a laptop personal computer. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, and an external connection port 7214. A display portion 7000 is incorporated in the housing 7211.

[0521] The light-emitting device of one embodiment of the present invention can be applied to the display portion 7000. Therefore, the electronic device can be provided with high reliability.

[0522] 21(E) and 21(F) show an example of digital signage.

[0523] 21E includes a housing 7301, a display portion 7000, and a speaker 7303. The digital signage 7300 may further include an LED lamp, an operation key (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0524] 21F shows a digital signage 7400 attached to a cylindrical pillar 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.

[0525] 21E and 21F, the light-emitting device of one embodiment of the present invention can be applied to the display portion 7000. Therefore, the electronic device can have high reliability.

[0526] The larger the display unit 7000, the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it catches people's attention, which can increase the advertising effect of, for example, advertisements.

[0527] Applying a touch panel to the display unit 7000 is preferable because it not only displays images or videos on the display unit 7000 but also allows the user to intuitively operate it. Furthermore, when used for providing information such as route information or traffic information, usability can be improved by intuitive operation.

[0528] 21(E) and 21(F), the digital signage 7300 or the digital signage 7400 is preferably capable of wirelessly linking with an information terminal 7311 or an information terminal 7411 such as a smartphone carried by a user. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411. By operating the information terminal 7311 or the information terminal 7411, the display on the display unit 7000 can be switched.

[0529] In addition, a game can be executed on the digital signage 7300 or the digital signage 7400 using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller). This allows an unspecified number of users to participate in and enjoy the game at the same time.

[0530] The electronic devices shown in Figures 22(A) to 22(G) have a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), a connection terminal 9006, a sensor 9007 (including a function of measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor or infrared rays), a microphone 9008, etc.

[0531] 22(A) to 22(G) have various functions. For example, the electronic devices may have a function of displaying various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function of displaying a calendar, date, or time, a function of controlling processing by various software (programs), a wireless communication function, a function of reading and processing a program or data recorded on a recording medium, and the like. Note that the functions of the electronic devices are not limited to these, and the electronic devices may have various functions. The electronic devices may have multiple display units. In addition, the electronic devices may have a function of providing a camera or the like in the electronic device, taking still images or videos, and storing them in a recording medium (external or built-in to the camera), a function of displaying the taken images on the display unit, and the like.

[0532] The electronic devices shown in FIGS. 22A to 22G will be described in detail below.

[0533] FIG. 22A is a perspective view showing a mobile information terminal 9171. The mobile information terminal 9171 can be used as, for example, a smartphone. Note that the mobile information terminal 9171 may be provided with a speaker 9003, a connection terminal 9006, a sensor 9007, or the like. The mobile information terminal 9171 can display text and image information on a plurality of surfaces. FIG. 22A shows an example in which three icons 9050 are displayed. Information 9051 shown in a dashed rectangle can also be displayed on another surface of the display unit 9001. Examples of the information 9051 include notification of incoming e-mail, SNS, phone call, etc., the title of e-mail or SNS, the sender's name, date and time, time, remaining battery level, radio wave intensity, and the like. Alternatively, the icon 9050, etc. may be displayed at the position where the information 9051 is displayed.

[0534] 22(B) is a perspective view showing a mobile information terminal 9172. The mobile information terminal 9172 has a function of displaying information on three or more surfaces of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different surfaces. For example, a user can check information 9053 displayed at a position that can be observed from above the mobile information terminal 9172 while storing the mobile information terminal 9172 in a breast pocket of clothes. The user can check the display without taking the mobile information terminal 9172 out of the pocket and determine, for example, whether to answer a call.

[0535] 22C is a perspective view of a tablet terminal 9173. The tablet terminal 9173 is capable of executing various applications such as mobile phone, e-mail, text browsing and creation, music playback, Internet communication, computer games, etc. The tablet terminal 9173 has a display unit 9001, a camera 9002, a microphone 9008, and a speaker 9003 on the front side of a housing 9000, operation keys 9005 as operation buttons on the left side of the housing 9000, and a connection terminal 9006 on the bottom.

[0536] 22D is a perspective view showing a wristwatch-type mobile information terminal 9200. The mobile information terminal 9200 can be used as, for example, a smart watch (registered trademark). The display surface of the display unit 9001 is curved, and display can be performed along the curved display surface. The mobile information terminal 9200 can also perform hands-free conversation by communicating with, for example, a headset capable of wireless communication. The mobile information terminal 9200 can also perform data transmission and reception with another information terminal and can be charged through a connection terminal 9006. Note that charging may be performed by wireless power supply.

[0537] 22(E) to 22(G) are perspective views showing a foldable mobile information terminal 9201. FIG. 22(E) is a perspective view of the mobile information terminal 9201 in an unfolded state, FIG. 22(G) is a perspective view of the mobile information terminal 9201 in a folded state, and FIG. 22(F) is a perspective view of a state in the middle of changing from one of FIG. 22(E) and FIG. 22(G) to the other. The mobile information terminal 9201 has excellent portability in a folded state, and has excellent viewability of the display due to a seamless wide display area in an unfolded state. A display portion 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by a hinge 9055. For example, the display portion 9001 can be bent with a curvature radius of 0.1 mm or more and 150 mm or less.

[0538] This embodiment mode can be combined with other embodiment modes or examples as appropriate. In addition, in the case where a plurality of configuration examples are shown in one embodiment mode in this specification, the configuration examples can be combined as appropriate. EXAMPLES

[0539] ((Synthesis Example 1)) Example 1 In this example, physical properties and a synthesis method of an organometallic complex according to one embodiment of the present invention will be described. Specifically, a synthesis method of (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazol-1-yl-2-ylidene-κC2]phenoxy-κC2}-9-[5-(methyl-d3)-4-phenyl-2-pyridinyl-κN]carbazole-2,1-diyl-κC)platinum(II) (abbreviation: Pt(mmtBubOcz5m4ppy-d3)) represented by structural formula (100) in Embodiment 1 will be described. The structure of Pt(mmtBubOcz5m4ppy-d3) is shown below.

[0540] [ka]

[0541] <Step 1: Synthesis of 4-phenyl-2-fluoro-5-picoline> 25g (110mmol) of 4-iodo-2-fluoro-5-picoline, 20g (110mmol) of phenylboronic acid, 44g (317mmol) of potassium carbonate (abbreviation: K2CO3), 420mL of 1,4-dioxane, and 110mL of water were added to a 1L three-neck flask. The mixture was degassed under reduced pressure, and the flask was replaced with nitrogen, after which 6.5g (5.6mmol) of tetrakis(triphenylphosphine)palladium(0) (abbreviation: Pd(PPh3)4) was added. The mixture was stirred for 15 hours under heating conditions at 85°C. After the reaction, the reaction mixture was concentrated under reduced pressure and extracted with dichloromethane. The product was then isolated and purified by silica gel column chromatography. A mixed solvent of hexane:dichloromethane = 6:4 was used as the developing solvent. The obtained fraction was concentrated under reduced pressure to obtain 16g of the target yellow oil in a yield of 83%. The synthetic scheme of 4-phenyl-2-fluoro-5-picoline is shown below in (a-1).

[0542] [ka]

[0543] <Step 2: Synthesis of 9-(5-methyl-4-phenylpyridin-2-yl)-2-bromocarbazole> In a 500 mL three-neck flask, 15 g (80 mmol) of 4-phenyl-2-fluoro-5-picoline, 16 g (66 mmol) of 2-bromocarbazole, 43 g (133 mmol) of cesium carbonate, and 150 mL of N,N-dimethylformamide (abbreviation: DMF) were added. The mixture was degassed under reduced pressure, and the atmosphere in the flask was replaced with nitrogen, and then the mixture was stirred for 24 hours under heating conditions at 120°C. After the reaction, the mixture was suction filtered using toluene. The filtrate was concentrated under reduced pressure, and the obtained crude product was isolated and purified by silica gel column chromatography. A mixed solvent of hexane:toluene = 5:1 was used as the developing solvent. The obtained fraction was concentrated under reduced pressure to obtain 11 g of the target yellow oil in a yield of 40%. The synthesis scheme of 9-(5-methyl-4-phenylpyridin-2-yl)-2-bromocarbazole is shown in (a-2) below.

[0544] [ka]

[0545] <Step 3: Synthesis of 9-[5-(methyl-d3)-4-phenylpyridin-2-yl]-2-bromocarbazole> 7.0g (17mmol) of 9-(5-methyl-4-phenylpyridin-2-yl)-2-bromocarbazole and 97mg (10mmol) of sodium tert-butoxide were added to a 100mL three-neck flask, followed by 24mL (340mmol) of dimethylsulfoxide-d6 (abbreviation: DMSO-d6). The mixture was degassed under reduced pressure, the flask was replaced with nitrogen, and the mixture was stirred at room temperature for 2 hours and 30 minutes. After the reaction, the reaction mixture was extracted with toluene. The product was then isolated and purified by silica gel column chromatography. A mixed solvent of hexane:toluene = 9:1 was used as the developing solvent, and the ratio of toluene was gradually increased, and finally a mixed solvent of hexane:toluene = 1:1 was used as the developing solvent. The obtained fraction was concentrated under reduced pressure to obtain 5.8g of a yellow oil in a yield of 82%. The synthesis scheme of 9-[5-(methyl-d3)-4-phenylpyridin-2-yl]-2-bromocarbazole is shown in (a-3) below.

[0546] [ka]

[0547] <Step 4: Synthesis of 9-[5-(methyl-d3)-4-phenylpyridin-2-yl]-2-hydroxycarbazole> In a 200 mL eggplant flask, 5.8 g (14 mmol) of 9-[5-(methyl-d3)-4-phenylpyridin-2-yl]-2-bromocarbazole, 2.8 g (29 mmol) of sodium tert-butoxide, 56 mL of dimethyl sulfoxide (abbreviation: DMSO), and 14 mL of water were added. The mixture was degassed under reduced pressure, and the flask was replaced with nitrogen, after which 69 mg (0.69 mmol) of copper chloride (I) and 0.23 g (0.69 mmol) of N1,N2-bis(4-hydroxy-2,6-dimethylphenyl)oxalamide were added. The mixture was stirred for 3 hours under heating conditions at 110°C. After the reaction, the reaction solution was transferred to a 2 L Erlenmeyer flask, and 1.5 L of water was added. The precipitated solid was collected by suction filtration to obtain a yellowish white solid. The obtained compound was recrystallized with toluene to obtain 3.8 g of the target yellowish white solid in a yield of 77%. The synthesis scheme of 9-[5-(methyl-d3)-4-phenylpyridin-2-yl]-2-hydroxycarbazole is shown in (a-4) below.

[0548] [ka]

[0549] <Step 5: Synthesis of 2-[3-(benzoimidazol-1-yl)phenoxy]-9-[5-(methyl-d3)-4-phenylpyridin-2-yl]carbazole> In a 200 mL three-neck flask, 3.8 g (11 mmol) of 9-[5-(methyl-d3)-4-phenylpyridin-2-yl]-2-hydroxycarbazole, 4.4 g (16 mmol) of 1-(3-bromophenyl)benzimidazole, 4.6 g (22 mmol) of tripotassium phosphate, and 110 mL of dimethyl sulfoxide (abbreviation: DMSO) were added. The mixture was degassed under reduced pressure, and the atmosphere in the flask was replaced with nitrogen, after which 210 mg (1.1 mmol) of copper iodide and 130 mg (1.1 mmol) of picolinic acid were added. The mixture was stirred for 6 hours under heating conditions at 160°C. After the reaction, the reaction mixture was extracted with ethyl acetate. Then, it was purified by silica gel column chromatography. A mixed solvent of toluene:ethyl acetate = 10:1 was used as the developing solvent. The obtained fraction was concentrated under reduced pressure. Then, the product was isolated and purified by high performance liquid chromatography using chloroform as a developing solvent to obtain 5.1 g of the target brown solid in a yield of 87%. The synthesis scheme of 2-[3-(benzoimidazol-1-yl)phenoxy]-9-[5-(methyl-d3)-4-phenylpyridin-2-yl]carbazole is shown in (a-5) below.

[0550] [ka]

[0551] <Step 6: Synthesis of 1-(3,5-di-tert-butylphenyl)-3-[3-({9-[5-(methyl-d3)-4-phenylpyridin-2-yl]carbazol-2-yl}oxy)phenyl]benzimidazolium-1,1,1-trifluoromethanesulfonic acid> In a 200mL three-neck flask, 5.1g (9.3mmol) of 2-[3-(benzoimidazol-1-yl)phenoxy]-9-[5-(methyl-d3)-4-phenylpyridin-2-yl]carbazole, 8.2g (14mmol) of (3,5-di-tert-butylphenyl)(mesityl)iodonium trifluoromethanesulfonate, and 47mL of N,N-dimethylformamide (abbreviation: DMF) were added. The mixture was degassed under reduced pressure, and the atmosphere in the flask was replaced with nitrogen, and then 254mg (1.4mmol) of copper acetate (II) was added. The mixture was stirred at 100°C for 8 hours. After the reaction, the solvent was distilled off, and the resulting residue was purified by silica gel column chromatography using dichloromethane:acetone=9:1 as a developing solvent, and 3.4g of the target brown oil was obtained in a yield of 41%. The synthesis scheme of 1-(3,5-di-tert-butylphenyl)-3-[3-({9-[5-(methyl-d3)-4-phenylpyridin-2-yl]carbazol-2-yl}oxy)phenyl]benzimidazolium-1,1,1-trifluoromethanesulfonic acid is shown in the following (a-6).

[0552] [ka]

[0553] <Step 7: Synthesis of Pt(mmtBubOcz5m4ppy-d3)> 3.4g (3.8mmol) of 1-(3,5-di-tert-butylphenyl)-3-[3-({9-[5-(methyl-d3)-4-phenylpyridin-2-yl]carbazol-2-yl}oxy)phenyl]benzimidazolium-1,1,1-trifluoromethanesulfonic acid, 950mg (12mmol) of sodium acetate, and 150mL of N,N-dimethylformamide were added to a 200mL three-neck flask. The mixture was degassed under reduced pressure, and the atmosphere in the flask was replaced with nitrogen, after which 1.4g (3.8mmol) of dichloro(1,5-cyclooctadiene)platinum(II) (abbreviation: Pt(COD)Cl2) was added. The mixture was reacted by heating at 160°C for 4 hours. The reaction solution was extracted with dichloromethane. The product was then purified by silica gel column chromatography using a hexane:toluene=1:9 mixture as a developing solvent, and recrystallized using a mixed solvent of toluene and ethanol to obtain 400 mg of the target yellow solid in an 11% yield. The synthesis scheme of Pt(mmtBubOcz5m4ppy-d3) represented by structural formula (100) is shown in (a-7) below.

[0554] [ka]

[0555] The obtained yellow solid (400 mg) was purified by sublimation for 18 hours under the conditions of argon flow rate of 5 mL / min, pressure of 3.0 Pa, and heating temperature of 290° C. As a result, 250 g of a yellow solid was obtained with a recovery rate of 63%.

[0556] <Characteristics of organometallic complexes> Nuclear magnetic resonance spectroscopy of the pale yellow solid obtained in step 7 above ( 1 The results of the analysis by H-NMR are shown below. 1 The H-NMR chart is shown in Figure 23. From this result, it was confirmed that the organometallic complex Pt(mmtBubOcz5m4ppy-d3), which is one embodiment of the present invention and is represented by the above structural formula (100), was obtained in this synthesis example.

[0557] 1 H NMR(CDCl3,300MHz):δ=8.89(s,1H),8.28(d,1H),8.07-8.04(m,1H),7.86-7.78(m,5H),7.72( d,1H),7.56-7.50(m,3H),7.45-7.31(m,8H),7.18-7.12(m,3H),1.49(brs,9H),1.16(brs,9H).

[0558] <Emission spectrum and absorption spectrum measurement> Next, the ultraviolet-visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and emission spectrum of the dichloromethane solution of Pt(mmtBubOcz5m4ppy-d3) were measured. The absorption spectrum was measured using an ultraviolet-visible spectrophotometer (V770 model, manufactured by JASCO Corporation). The emission spectrum was measured using a spectrofluorophotometer (FP-8600, manufactured by JASCO Corporation). The measurement results of the absorption spectrum and emission spectrum of the obtained dichloromethane solution are shown in Figure 24. The horizontal axis represents wavelength, and the vertical axis represents absorption intensity and emission intensity.

[0559] From the results in FIG. 24, in the dichloromethane solution of Pt(mmtBubOcz5m4ppy-d3), absorption peaks were observed near 422 nm, 371 nm, 314 nm, and 259 nm, and emission peaks were observed near 494 nm and 467 nm.

[0560] <Thermogravimetric measurement results> Thermogravimetry-Differential Thermal Analysis (TG-DTA) of Pt(mmtBubOcz5m4ppy-d3) was performed. The results are shown in Figure 25. A high vacuum differential thermobalance (TG-DTA2410SA, manufactured by Bruker AXS Co., Ltd.) was used for the measurement.

[0561] The measurements were performed under two conditions. The first condition was a temperature rise rate of 10°C / min, nitrogen flow (flow rate 200mL / min), and pressure conditions equivalent to atmospheric pressure. The second condition was a temperature rise rate of 10°C / min, nitrogen flow (flow rate 2.5mL / min), and pressure conditions of 10 Pa.

[0562] 25, in thermogravimetry-differential thermal analysis, it was found that the temperature (decomposition temperature) at which the weight determined by thermogravimetry was -5% of the weight at the start of the measurement for Pt(mmtBubOcz5m4ppy-d3) under atmospheric pressure was 473°C. On the other hand, when the measurement device was controlled at 10 Pa, it was found that the temperature (sublimation temperature) at which the weight determined by thermogravimetry was -5% of the weight at the start of the measurement was 305°C. Therefore, the difference between the sublimation temperature and the decomposition temperature was 168°C.

[0563] In other words, Pt(mmtBubOcz5m4ppy-d3) was shown to be a material with high heat resistance. In addition, since the difference between the sublimation temperature and the decomposition temperature is 100°C or more, when used in light-emitting devices, a stable deposition process is possible in the production process. Therefore, by using Pt(mmtBubOcz5m4ppy-d3), it is possible to provide light-emitting devices with good yield and high productivity. EXAMPLES

[0564] In this example, a light-emitting device 2A was fabricated using an organometallic complex having a phenyl group and an alkyl group containing deuterium, (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazol-1-yl-2-ylidene-κC]phenoxy-κC}-9-[5-(methyl-d)-4-phenyl-2-pyridinyl-κN]carbazole-2,1-diyl-κC)platinum(II) (abbreviation: Pt(mmtBubOcz5m4ppy-d3)) (100), which is one embodiment of the present invention, and a light-emitting device 2B was fabricated using an organometallic complex for comparison, PtON-TBBI.

[0565] The structural formulae of the organic compounds used in the light-emitting device 2A and the comparative light-emitting device 2B are shown below.

[0566] [ka]

[0567] As shown in Figure 26, each light-emitting device has a structure in which a hole injection layer 911, a hole transport layer 912, a light-emitting layer 913, an electron transport layer 914 and an electron injection layer 915 are sequentially stacked on a first electrode 901 formed on a glass substrate 900, and a second electrode 902 is stacked on the electron injection layer 915.

[0568] <Method of Fabricating Light-Emitting Device 2A> A first electrode 901 was formed as a transparent electrode on a glass substrate 900 by forming a film of indium tin oxide containing silicon oxide (ITSO) with a thickness of 70 nm by a sputtering method. 2 (2mm x 2mm).

[0569] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface was washed with water and baked at 200°C for 1 hour. -4 The substrate was introduced into a vacuum deposition apparatus whose inside had been reduced in pressure to about Pa, and vacuum baking was carried out at 170° C. for 30 minutes in a heating chamber in the vacuum deposition apparatus. Thereafter, the substrate was allowed to cool naturally.

[0570] Next, the substrate on which the first electrode 901 was formed was fixed to a substrate holder provided in a vacuum deposition apparatus so that the surface on which the first electrode 901 was formed faced downward. N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf) and an electron acceptor material (OCHD-003) having a molecular weight of 672 and containing fluorine were co-deposited on the first electrode 901 to a thickness of 10 nm such that the ratio of BBABnf:OCHD-003 was 1:0.1 (weight ratio) to form a hole injection layer 911.

[0571] Next, BBABnf was deposited on the hole injection layer 911 to a thickness of 30 nm, and then 9-[3-(triphenylsilyl)phenyl]-3,9'-bi-9H-carbazole (abbreviation: PSiCzCz) was deposited to a thickness of 5 nm to form a hole transport layer 912.

[0572] Next, on the hole transport layer 912, 9,9'-{6-[3-(triphenylsilyl)phenyl]-1,3,5-triazine-2,4-diyl}bis(9H-carbazole) (abbreviation: SiTrzCz2), PSiCzCz, and Pt(mmtBubOcz5m4ppy-d3) were co-deposited by a deposition method using resistance heating in a ratio of SiTrzCz2:PSiCzCz:Pt(mmtBubOcz5m4ppy-d3)=0.435:0.435:0.13 (weight ratio) to a film thickness of 35 nm to form a light emitting layer 913. Note that SiTrzCz2 and PSiCzCz are a combination that forms an exciplex.

[0573] Next, 2-phenyl-4,6-bis[3-(triphenylsilyl)phenyl]-1,3,5-triazine (abbreviation: mSiTrz) was evaporated onto the light-emitting layer 913 to a thickness of 5 nm, and then mSiTrz and 8-quinolinolato-lithium (abbreviation: Liq) were co-evaporated in a 1:1 (weight ratio) to a thickness of 20 nm to form an electron-transporting layer 914.

[0574] Next, lithium fluoride (LiF) was evaporated onto the electron transport layer 914 to a thickness of 1 nm, thereby forming an electron injection layer 915 .

[0575] Next, aluminum (Al) was evaporated onto the electron injection layer 915 to a thickness of 200 nm to form a second electrode 902 .

[0576] <Method of manufacturing comparative light-emitting device 2B> Next, a method for producing the comparative light emitting device 2B will be described.

[0577] The light emitting device 2B is different from the light emitting device 2A in the configuration of the light emitting layer 913. That is, in the light emitting device 2B, SiTrzCz2, PSiCzCz, and PtON-TBBI were co-deposited by a deposition method using resistance heating in a ratio of SiTrzCz2:PSiCzCz:PtON-TBBI=0.435:0.435:0.13 (weight ratio) to a film thickness of 35 nm to form the light emitting layer 913.

[0578] Other configurations were the same as those of the light-emitting device 2A.

[0579] The element structures of the light emitting device 2A and the light emitting device 2B are summarized in the following table, where X in the table represents Pt(mmtBubOcz5m4ppy-d3) or PtON-TBBI.

[0580] [Table 1]

[0581] <Light-emitting device characteristics> The above light-emitting device was sealed with a glass substrate in a nitrogen atmosphere glove box to prevent the light-emitting device from being exposed to the atmosphere (a sealant was applied around the element, and UV treatment was performed during sealing, followed by heat treatment at 80°C for 1 hour), and then the characteristics of the light-emitting device were measured.

[0582] The luminance-current density characteristics of the light-emitting device are shown in Figure 27, the luminance-voltage characteristics in Figure 28, the current efficiency-current density characteristics in Figure 29, the current density-voltage characteristics in Figure 30, the power efficiency-current density characteristics in Figure 31, the external quantum efficiency-current density characteristics in Figure 32, and the emission spectrum in Figure 33.

[0583] In addition, the current density of the light-emitting device is 10 mA / cm 2 The main characteristics of this product are shown in the table below. A spectroradiometer (SR-UL1R, manufactured by Topcon) was used to measure the luminance, CIE chromaticity, and emission spectrum. The external quantum efficiency was calculated using the luminance and emission spectrum measured using the spectroradiometer, assuming that the light distribution characteristic is a Lambertian type.

[0584] [Table 2]

[0585] 27 to 33, it was found that the light-emitting device 2A is a light-emitting device that operates with high efficiency. Therefore, it was confirmed that the light-emitting device 2A can provide a highly efficient light-emitting device by using an organometallic complex of platinum (Pt) having a phenyl group and an alkyl group containing deuterium in the light-emitting device.

[0586] Here, the HOMO and LUMO levels of Pt(mmtBubOcz5m4ppy-d3) were calculated by cyclic voltammetry (CV) measurements. An electrochemical analyzer (manufactured by BAS Co., Ltd., model number: ALS model 600A or 600C) was used for the measurements. The Pt(mmtBubOcz5m4ppy-d3) solution used in the measurements was dissolved in dehydrated dimethylformamide (DMF) as a solvent. In the measurements, the potential of the working electrode relative to the reference electrode was changed within an appropriate range to obtain the oxidation peak potential and the reduction peak potential, respectively. In addition, a platinum electrode (manufactured by BAS Co., Ltd., PTE platinum electrode) was used as the working electrode, a platinum electrode (manufactured by BAS Co., Ltd., Pt counter electrode (5 cm) for VC-3) was used as the auxiliary electrode, and an Ag / Ag+ electrode (manufactured by BAS Co., Ltd., RE7 nonaqueous solvent reference electrode) was used as the reference electrode. In addition, since the redox potential of the reference electrode was estimated to be -4.94 eV, the HOMO and LUMO levels of the compound were calculated from this value and the peak potential obtained. As a result, the HOMO level of Pt(mmtBubOcz5m4ppy-d3) was -5.5 eV, and the LUMO level was -2.58 eV. This shows that Pt(mmtBubOcz5m4ppy-d3) has a deep HOMO level.

[0587] In addition, the LUMO level of SiTrzCz2 and the HOMO level of PSiCzCz were calculated by cyclic voltammetry (CV) measurement. As a result, the LUMO level of SiTrzCz2 was -2.98 eV, and the HOMO level of PSiCzCz was -5.7 eV. In addition, the difference between the HOMO level of Pt(mmtBubOcz5m4ppy-d3) and the LUMO level of the host SiTrzCz2 was 2.52 eV.

[0588] From the above, it was found that the light-emitting device 2A is a light-emitting device that exhibits good characteristics in which exciplex formation between an organometallic complex of platinum (Pt) and a host is suppressed.

[0589] <Reliability test results> A reliability test was carried out on the light-emitting device 2A and the light-emitting device 2B. In FIG. 34, the luminance at the time when light emission started is taken as 100%, and the luminance at the time when light emission started is taken as 100%. 2 ) and changes in brightness (%) over time.

[0590] 34, the LT90 (h), which is the time elapsed until the measured luminance of each light-emitting device fabricated according to one embodiment of the present invention decreased to 90% of the initial luminance, was 51 hours for light-emitting device 2A and 44 hours for light-emitting device 2B. This shows that light-emitting device 2A is a more reliable light-emitting device than light-emitting device 2B.

[0591] Therefore, it was found that a highly reliable light-emitting device can be manufactured by using one embodiment of the present invention. EXAMPLES

[0592] ((Synthesis Example 2)) In this synthesis example, a synthesis example of the organometallic complex of the present invention represented by the following structural formula (115), (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazol-1-yl-2-ylidene-κC2]phenoxy-κC2}-9-[3,5-di(methyl-d3)-4-phenyl-2-pyridinyl-κN]carbazole-2,1-diyl-κC)platinum(II) (abbreviation: Pt(mmtBubOcz35dm4ppy-d6)) is specifically illustrated.

[0593] [ka]

[0594] <Step 1: Synthesis of 2-fluoro-3,5-dimethyl-4-phenylpyridine> First, 4.9 g of 2-fluoro-4-iodo-3,5-dimethylpyridine, 2.7 g of phenylboronic acid, 8.3 g of potassium carbonate, 80 mL of 1,4-dioxane, and 20 mL of water were placed in a three-neck flask equipped with a reflux condenser, and the inside of the flask was replaced with nitrogen. After degassing by stirring the inside of the flask under reduced pressure, 1.4 g of tetrakis(triphenylphosphine)palladium(0) (abbreviation: Pd(PPh3)4) was added and reacted by stirring at 85°C for 23 hours.

[0595] After a certain time had passed, extraction with toluene was performed. The resulting residue was purified by silica gel column chromatography using toluene as a developing solvent to obtain the target product (light yellow solid, yield 3.6 g, 90%). The synthesis scheme of step 1 is shown below in (c-1).

[0596] [ka]

[0597] <Step 2: Synthesis of 2-bromo-9-(3,5-dimethyl-4-phenylpyridin-2-yl)carbazole> Next, 3.6 g of 2-fluoro-3,5-dimethyl-4-phenylpyridine obtained in step 1 above, 4.6 g of 2-bromocarbazole, 12 g of cesium carbonate, and 40 mL of N-methyl-2-pyrrolidone (abbreviation: NMP) were placed in a three-neck flask equipped with a reflux condenser, and the inside of the flask was replaced with nitrogen. After that, the mixture was reacted by stirring at 120°C for 18.5 hours.

[0598] After a certain time had passed, extraction with toluene was performed. The resulting residue was purified by silica gel column chromatography using hexane:toluene=1:5 as a developing solvent to obtain the target product (colorless oil, yield 6.9 g, 90%). The synthesis scheme of step 2 is shown below in (c-2).

[0599] [ka]

[0600] <Step 3: Synthesis of 2-bromo-9-[3,5-di(methyl-d3)-4-phenylpyridin-2-yl]carbazole> Next, 6.9 g of 2-bromo-9-(3,5-dimethyl-4-phenylpyridin-2-yl)carbazole obtained in step 2 above, 23 mL of dimethylsulfoxide-d6 (abbreviation: DMSO-d6), and 0.93 g of sodium tert-butoxide were placed in a recovery flask, and the inside of the flask was replaced with nitrogen. After that, the mixture was reacted by stirring at room temperature for 16 hours.

[0601] After a certain time had passed, extraction with toluene was performed. The obtained residue was purified by silica gel column chromatography using hexane:toluene=1:5 as a developing solvent to obtain the target product (white solid, yield 5.8 g, 83%). The synthesis scheme of step 3 is shown below in (c-3).

[0602] [ka]

[0603] <Step 4: Synthesis of 2-hydroxy-9-[3,5-di(methyl-d3)-4-phenylpyridin-2-yl]carbazole> Next, 5.8 g of 2-bromo-9-[3,5-di(methyl-d3)-4-phenylpyridin-2-yl]carbazole obtained in step 3 above, 2.7 g of sodium tert-butoxide, 54 mL of dimethyl sulfoxide, and 13 mL of water were placed in a three-neck flask equipped with a reflux condenser, and the inside was replaced with nitrogen. After degassing by stirring the inside of the flask under reduced pressure, 0.066 g of copper chloride (I) (abbreviation: CuCl) and 0.22 g of N1,N2-bis(4-hydroxy-2,6-dimethylphenyl)oxalamide were added, and the mixture was reacted by stirring at 110°C for 2 hours.

[0604] After a certain time had passed, extraction with ethyl acetate was performed. The obtained residue was purified by recrystallization with toluene to obtain the target product (light orange solid, yield 4.0 g, 80%). The synthesis scheme of step 4 is shown below in (c-4).

[0605] [ka]

[0606] <Step 5: Synthesis of 2-[3-(benzoimidazol-1-yl)phenoxy]-9-[3,5-di(methyl-d3)-4-phenylpyridin-2-yl]carbazole> Next, 1.9 g of 2-hydroxy-9-[3,5-di(methyl-d3)-4-phenylpyridin-2-yl]carbazole obtained in step 4 above, 1.5 g of 1-(3-bromophenyl)benzimidazole, 2.2 g...

Claims

1. An organometallic complex represented by the general formula (G1). 【Chemistry 1】 (In the formula, R １ , R ２ , and R ４ ~R ２２ Each independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group, and R ２ or R ４ At least one of them represents an alkyl group having 1 to 10 carbon atoms, R １８ ~R ２２ (One or more of these represent an alkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.)

2. An organometallic complex represented by the general formula (G1). 【Chemistry 2】 (In the formula, R １ , R ２ , and R ４ to R ２２ each independently represent hydrogen (including deuterium), an alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and R ２ or R ４ at least one of them represents an alkyl group having 1 to 10 carbon atoms containing deuterium, and one or more of R １８ to R ２２ each represent an alkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.)

3. An organometallic complex represented by the general formula (G1). 【Transformation 3】 (In the formula, R １ , R ２ , and R ４ ~R ２２ Each independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group, and R ２ R represents an alkyl group having 1 to 10 carbon atoms. １８ ~R ２２ (One or more of these represent an alkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.)

4. An organometallic complex represented by the general formula (G1). 【Chemistry 4】 (In the formula, R １ , R ２ , and R ４ ~R ２２ Each independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group, and R ２ R represents an alkyl group having 1 to 10 carbon atoms and containing deuterium. １８ ~R ２２ (One or more of these represent an alkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.)

5. An organometallic complex represented by the general formula (G1). 【Transformation 5】 (In the formula, R １ , R ２ , R ４ ~R １８ , R ２０ , and R ２２ Each independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group, and R ２ or R ４ At least one of them represents an alkyl group having 1 to 10 carbon atoms, R １９ and R ２１ Each of these independently represents an alkyl group having 3 to 10 carbon atoms.

6. An organometallic complex represented by the general formula (G1). 【Transformation 6】 (In the formula, R １ , R ２ , R ４ ~R １８ , R ２０ , and R ２２ Each independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group, and R ２ or R ４ At least one of them represents a C1 to C10 alkyl group having deuterium, R １９ and R ２１ Each of these independently represents an alkyl group having 3 to 10 carbon atoms.

7. An organometallic complex represented by the general formula (G1). 【Transformation 7】 (In the formula, R １ , R ２ , and R ４ ~R ２２ Each independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group, and R ２ or R ４ At least one of them represents an alkyl group having 1 to 10 carbon atoms, R １８ ~R ２２ One or more of these represent the following general formula (R-1). 【Transformation 8】 (In the formula, R ３１ ~R ３５ Each of these independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group.

8. An organometallic complex represented by the general formula (G1). 【Chemistry 9】 (In the formula, R １ , R ２ , R ４ ~R １７ and R １９ ~R ２１ Each independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group, and R ２ or R ４ At least one of them represents a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, R １８ and R ２２ Any one of these represents the following general formula (R-1). 【Chemistry 10】 (In the formula, R ３１ ~R ３５ Each of these independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group.

9. An organometallic complex represented by the general formula (G1). 【Chemistry 11】 (In the formula, R １ , R ２ , R ４ ~R １１ , R １３ ~R １７ and R １９ ~R ２１ Each independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group, and R ２ or R ４ At least one of them represents an alkyl group having 1 to 10 carbon atoms, R １２ R represents an alkyl group having 1 to 10 carbon atoms. １８ and R ２２ Any one of these represents the following general formula (R-1). 【Chemistry 12】 (In the formula, R ３１ ~R ３５ Each of these independently represents hydrogen (including deuterium), a C1 to C10 alkyl group, or a substituted or unsubstituted C6 to C18 aryl group.

10. An organometallic complex represented by structural formula (100), structural formula (115), structural formula (119), structural formula (120), or structural formula (121). 【Chemistry 13】

11. A light-emitting device comprising an organometallic complex according to any one of claims 1 to 10.

Images