Light-emitting devices

Abstract

The present invention provides a novel compound, a synthesis method for the novel compound, and an organic device that uses the novel compound. Provided is a compound represented by general formula (G1). In general formula (G1), R1, R2, and R5–R7 each independently represent any of hydrogen (including heavy hydrogen), a C1–10 alkyl group, a substituted or unsubstituted C1–60 aryl group, and a substituted or unsubstituted C1–60 heteroaryl group. R3 represents a condensed ring of 4–10 rings that includes nitrogen as a ring-forming element, and R4 represents any of a substituted or unsubstituted C1–60 condensed ring, a substituted or unsubstituted aryl group that has a molecular weight of at least 78, and a substituted or unsubstituted heteroaryl group that has a molecular weight of at least 80. At least one of A1–A3 represents nitrogen, the others represent a substituted carbon, and the substituents at A1–A3 are each independently any of hydrogen (including heavy hydrogen), a C1–10 alkyl group, a substituted or unsubstituted C1–60 aryl group, and a substituted or unsubstituted C1–60 heteroaryl group.

Description

Organic compounds, organic devices, light-emitting devices and electronic devices

[0001] One embodiment of the present invention relates to an organic compound, an organic device, a 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 one embodiment of the present invention is not limited to the above technical field. The technical field of one embodiment of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. Alternatively, one embodiment of the present invention relates to a process, a machine, manufacture, or a composition of matter. Therefore, more specifically, examples of the technical field of one embodiment of the present invention disclosed in this 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 memory device, an imaging device, a driving method thereof, or a manufacturing method thereof.

[0002] Light-emitting devices (also called organic EL elements or light-emitting elements) that utilize electroluminescence (EL) using organic compounds are becoming increasingly practical. The basic structure of these light-emitting devices is a pair of electrodes sandwiching an organic compound layer (EL layer) containing a light-emitting material between them. 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.

[0003] Because these light-emitting devices are self-luminous, they offer better visibility than liquid crystal displays and are suitable for use as display pixels. Another major advantage of displays using these light-emitting devices is that they do not require a backlight and can be made thin and lightweight. Another feature is their extremely fast response time.

[0004] Furthermore, these light-emitting devices can have a continuous light-emitting layer formed two-dimensionally, enabling them to emit light in a planar form. This is a feature that is difficult to obtain with point light sources such as incandescent lamps or LEDs, or linear light sources such as fluorescent lamps, making them highly useful as planar light sources for lighting and other applications.

[0005] Displays or lighting devices using such light-emitting devices are suitable for use in a variety of electronic devices, but research and development is ongoing to find light-emitting devices with better efficiency and lifespan.

[0006] An example of an electron transport material having excellent longevity for organic electroluminescent devices is the azine compound disclosed in Patent Document 1. However, further improvements have been required from various viewpoints, such as improvement of device lifetime and high temperature resistance.

[0007] JP 2011-063584 A

[0008] An object of one embodiment of the present invention is to provide a novel organic compound.An object of one embodiment of the present invention is to provide a synthesis method for a novel organic compound.An object of one embodiment of the present invention is to provide a novel electron-transporting material.An object of one embodiment of the present invention is to provide a novel organic device.An object of one embodiment of the present invention is to provide a light-emitting element with high emission efficiency.

[0009] Another object of one embodiment of the present invention is to provide a compound having a high glass transition temperature Tg.

[0010] Another object of one embodiment of the present invention is to provide a highly stable compound.

[0011] Another object of one embodiment of the present invention is to provide an organic device with high heat resistance.

[0012] Another object of one embodiment of the present invention is to provide an organic device that has a long operating lifetime or suffers little luminance deterioration when driven at high temperatures.

[0013] Another object of one embodiment of the present invention is to provide an organic device that exhibits little voltage fluctuation when driven at high temperatures.

[0014] In this specification, the term "organic device" (also referred to as "organic element") refers to any object containing an organic compound (excluding humans). Examples of organic devices include light-emitting devices (also referred to as "light-emitting elements") and light-receiving devices (also referred to as "light-receiving elements"). Examples of organic devices include an object having an organic compound layer (a thin film layer of about several micrometers or thinner) between a pair of electrodes. The term "organic device" may refer not only to objects having electrodes, but also to objects having an organic compound layer (such as a vapor-deposited film or a coated film) on a substrate, or objects containing an organic compound in a solvent. The term "organic device" may also refer to objects including layers (such as a cap layer, a partition wall, a sealing layer, or a color filter) provided around the electrodes.

[0015] 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 need to solve all of these problems. Note that problems other than these will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract other problems from the description in the specification, drawings, claims, etc.

[0016] One embodiment of the present invention is a novel azine compound, a method for manufacturing the azine compound, or a novel organic device including the azine compound.

[0017] Another embodiment of the present invention is an organic compound represented by General Formula (G1).

[0018]

[0019] In addition, in general formula (G1), R １ , R ２ , and R ５ ~R ７ R each independently represents any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ３ represents a condensed ring having 4 to 10 rings and containing nitrogen as an element forming the ring, R ４represents any one of a substituted or unsubstituted fused ring having 1 to 60 carbon atoms, a substituted or unsubstituted aryl group having a molecular weight of 78 or more, and a substituted or unsubstituted heteroaryl group having a molecular weight of 80 or more. １ or A ３ One of the groups represents nitrogen, and the others represent nitrogen or carbon. When carbon is present, each group is independently bonded to any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms.

[0020] Another embodiment of the present invention is a compound represented by the general formula (G1), ３ represents general formula (G1-1), and R ４ is an organic compound represented by any one of general formulae (G1-2) to (G1-6).

[0021]

[0022] In addition, in the general formula (G1-1), A １１ or A ２２ One of the groups represents nitrogen, another represents carbon, and the others each independently represent nitrogen or carbon. １１ or A ２２ One of the carbons in the general formula (G1) is bonded to the group represented by the general formula (G1), and the others are bonded to hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, or a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. １１ or A ２２ Among the substituents bonded to, adjacent groups may be bonded to each other to form a ring.

[0023]

[0024] In addition, in the general formula (G1-2), A ４１ or A ４８ Any one of A represents carbon, and the others each independently represent nitrogen or carbon. ４１ or A ４８One of the carbons in the formula (G1) is bonded to the formula (G1), and the others are each independently bonded to any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ４１ or A ４８ Among the substituents bonded to A, adjacent groups may be bonded to each other to form a ring. ５１ or A ６０ Any one of A represents carbon, and the others each independently represent nitrogen or carbon. ５１ or A ６０ One of the carbons in the formula (G1) is bonded to the formula (G1), and the others are each independently bonded to any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ５１ or A ６０ Among the substituents bonded to A, adjacent groups may be bonded to each other to form a ring. ６１ or A ６８ Any one of A represents carbon, and the others each independently represent nitrogen or carbon. ６９ represents nitrogen, carbon, sulfur or oxygen. ６１ or A ６８ Carbon or A ６９ one of the nitrogens in the formula (G1) is bonded to General Formula (G1), and the others each independently represent any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ６１ or A ６８ Among the substituents bonded to A, adjacent groups may be bonded to each other to form a ring. ７１ or A ８０ Any one of A represents carbon, and the others each independently represent nitrogen or carbon. ７１ or A ８０One of the carbons in the formula (G1) is bonded to the formula (G1), and the others each independently represent any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ７１ or A ８０ Among the substituents bonded to A, adjacent groups may be bonded to each other to form a ring. ８１ or A ９２ Any one of A represents carbon, and the others each independently represent nitrogen or carbon. ８１ or A ９２ One of the carbons in the formula (G1) is bonded to the formula (G1), and the others each independently represent any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ８１ or A ９２ Among the substituents bonded to, adjacent groups may be bonded to each other to form a ring.

[0025] Another embodiment of the present invention is an organic compound represented by structural formula (100).

[0026]

[0027] Another embodiment of the present invention is a compound represented by the formula (G1) above, wherein R １ and R ２ is an organic compound that is a substituted or unsubstituted phenyl group.

[0028] Another embodiment of the present invention is an organic compound represented by general formula (G1) and having a glass transition temperature of 150° C. or higher.

[0029] Another embodiment of the present invention is a compound represented by the formula (G1) above, wherein R ３ and R ４ is an organic compound having a molecular weight of 150 or more.

[0030] Another embodiment of the present invention is an organic device including any of the above organic compounds.Another embodiment of the present invention is a light-emitting device including any of the above devices and a transistor or a substrate.

[0031] Another embodiment of the present invention is an electronic device including any of the above organic compounds.Another embodiment of the present invention is an electronic device including any of the above light-emitting devices and a sensor, an operation button, a speaker, or a microphone.

[0032] Another embodiment of the present invention is a light-emitting device comprising an anode, an emitting layer, an electron transport layer having an azine compound, a cathode, and a capping layer, wherein the refractive index of the azine compound is smaller than the refractive index of a material of the capping layer and the refractive index of a host material of the emitting layer.

[0033] Another embodiment of the present invention is a light-emitting device including an anode, a hole-transport layer, a light-emitting layer, an electron-transport layer including an azine compound, and a cathode, in which the glass transition temperature of the azine compound is higher than the glass transition temperature of a material included in the hole-transport layer and the glass transition temperature of a host material of the light-emitting layer.

[0034] Another embodiment of the present invention is a light-emitting device including an anode, a hole-transport layer, a light-emitting layer, an electron-transport layer including an azine compound, a cathode, and a partition wall, in which the electron-transport layer has a region overlapping with the partition wall, and the glass transition temperature of the azine compound is higher than the glass transition temperatures of a material included in the hole-transport layer and a host material of the light-emitting layer.

[0035] These solutions do not preclude the existence of other solutions. One embodiment of the present invention does not necessarily have to include all of these solutions. Solutions other than these will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract solutions other than these from the description in the specification, drawings, claims, etc.

[0036] In one embodiment of the present invention, a novel organic compound can be provided. In another embodiment of the present invention, a novel carrier-transporting material can be provided. In another embodiment of the present invention, a novel host material can be provided. In another embodiment of the present invention, a compound with a high glass transition temperature can be provided. In another embodiment of the present invention, a highly stable compound can be provided. In another embodiment of the present invention, a novel organic device can be provided. In another embodiment of the present invention, an organic device with high emission efficiency can be fabricated. In another embodiment of the present invention, an organic device with low power consumption can be provided. In another embodiment of the present invention, a highly reliable organic device can be provided. In another embodiment of the present invention, a thin film (also referred to as an organic compound layer) using the novel organic compound can be provided.

[0037] According to another embodiment of the present invention, a light-emitting device, an electronic device, and a display device with high emission efficiency can be provided. According to another embodiment of the present invention, a light-emitting device, an electronic device, and a display device with low power consumption can be provided. According to another embodiment of the present invention, a light-emitting device, an electronic device, and a display device with high reliability can be provided.

[0038] 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 other effects from the description in the specification, drawings, claims, etc.

[0039] FIGS. 1A to 1E are diagrams illustrating a configuration of a light-emitting device according to an embodiment. FIGS. 2A to 2D are diagrams illustrating a light-emitting device according to an embodiment. FIGS. 3A to 3C are diagrams illustrating a manufacturing method of a light-emitting device according to an embodiment. FIGS. 4A to 4C are diagrams illustrating a manufacturing method of a light-emitting device according to an embodiment. FIGS. 5A to 5C are diagrams illustrating a manufacturing method of a light-emitting device according to an embodiment. FIGS. 6A to 6D are diagrams illustrating a manufacturing method of a light-emitting device according to an embodiment. FIGS. 7A to 7E are diagrams illustrating a light-emitting device according to an embodiment. FIGS. 8A to 8F are diagrams illustrating a device and pixel arrangement according to an embodiment. FIGS. 9A to 9C are diagrams illustrating a pixel circuit according to an embodiment. FIG. 10 is a diagram illustrating a light-emitting device according to an embodiment. FIGS. 11A to 11E are diagrams illustrating an electronic device according to an embodiment. FIGS. 12A to 12E are diagrams illustrating an electronic device according to an embodiment. FIGS. 13A and 13B are diagrams illustrating an electronic device according to an embodiment. FIGS. 14A and 14B are diagrams illustrating a lighting device according to an embodiment. FIG. 15 is a diagram illustrating a lighting device according to an embodiment. 16A to 16C are diagrams illustrating a light-emitting device and a light-receiving device according to an embodiment. FIGS. 17A and 17B are diagrams illustrating a light-emitting device and a light-receiving device according to an embodiment. FIGS. 18A and 18B are diagrams illustrating a light-emitting device and a light-receiving device according to an embodiment. １ 1H-NMR spectrum. FIG. 19 shows the absorption spectrum and emission spectrum of Pn-mDBqPTzn in a dichloromethane solution. FIG. 20 shows the absorption spectrum and emission spectrum of a thin film of Pn-mDBqPTzn. FIG. 21 shows the emission spectra of light-emitting device 1 and light-emitting device 2. FIG. 22 shows the external quantum efficiency-luminance characteristics of light-emitting device 1 and light-emitting device 2. FIG. 23 shows the current-voltage characteristics of light-emitting device 1 and light-emitting device 2. FIG. 24 shows the change in luminance with respect to the operating time of light-emitting device 1 and light-emitting device 2 at room temperature. FIG. 25 shows the change in luminance with respect to the operating time of light-emitting device 1 and light-emitting device 2 at 85°C.

[0040] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be readily understood by those skilled in the art that various changes in form and details can be made without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the description of the embodiments shown below.

[0041] Embodiment 1 In this embodiment, an organic compound (also referred to as a compound of the present application) of one embodiment of the present invention will be described. The compound of one embodiment of the present invention is an organic compound having an azine skeleton (also referred to as an azine compound). The azine skeleton refers to a skeleton in which one or more carbon atoms in a benzene ring are substituted with nitrogen, and examples thereof include a pyridine skeleton, a pyrazine skeleton, a pyrimidine skeleton, a pyridazine skeleton, and a triazine skeleton. The compound having an azine skeleton is, for example, an organic compound represented by the following general formula (G1).

[0042]

[0043] In addition, in general formula (G1), R １ ~R ７ each independently represent any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms.

[0044] Also, R ３ or R ４ Preferably, one of R represents a condensed ring having 4 to 10 rings and containing nitrogen as an element forming the ring. ３ or R ４ The other preferably represents any one of a substituted or unsubstituted fused ring having 1 to 60 carbon atoms, a substituted or unsubstituted aryl group having a molecular weight of 78 or more, and a heteroaryl group having a molecular weight of 80 or more.

[0045] R ３ or R ４By having a fused ring, the carrier transport property can be improved. In particular, by having three or more fused rings, preferably four or more fused rings, the carrier transport property can be further improved. Furthermore, by using a fused ring (bent fused ring) having a helicene structure such as phenanthrene, triphenylene, or dibenzoquinoxaline, the band gap can be widened and the T1 level and S1 level can be increased.

[0046] Also, A １ or A ３ One of the groups represents nitrogen, and the others represent nitrogen or carbon. In the case of carbon, it is preferable that each of the groups independently binds to any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms.

[0047] Also, R １ and R ２ Preferably, each independently contains an aryl group having a molecular weight of 70 or more or a heteroaryl group having a molecular weight of 70 or more. １ and R ２ Preferably, each independently contains an aryl group having a molecular weight of 150 or more or a heteroaryl group having a molecular weight of 150 or more.

[0048] Increasing the molecular weight of the compound and the substituent can improve the resistance (for example, heat resistance) of the compound and also improve the amorphous property. That is, it is possible to increase the glass transition temperature Tg. In addition, by increasing the molecular weight, the solubility of the compound in a solvent can be reduced, and the yield can be improved by a purification process such as recrystallization. Note that if the molecular weight is too large, sublimation becomes difficult, so R １ ~R ４ The molecular weight of each of R is preferably 1000 or less, more preferably 500 or less. １ ~R ４ The molecular weight of each of these is preferably 70 or more and 1,000 or less, more preferably 70 or more and 500 or less.

[0049] Furthermore, by having a fused ring in the substituent or by increasing the molecular weight, the resistance (for example, stability) of the compound can be improved. ３ or R ４ As the substituent, it is preferable to use a condensed ring such as a naphthyl group rather than a phenyl group, and to use a substituent having a larger molecular weight than a phenyl group.

[0050] In this specification, molecular weights and atomic weights are expressed by rounding off to the first decimal place for simplicity. １ is a phenyl group, R １ The molecular weight of ６ H ５ = 77. In the case of a naphthyl group, its molecular weight is C １０ H ７ = 127. The same applies to other substituents.

[0051] In addition, in general formula (G1), R ３ or R ４ one of the groups represents general formula (G1-1), and R ３ or R ４ The other preferably represents any one of general formulae (G1-2) to (G1-6).

[0052]

[0053] In addition, in the general formula (G1-1), A １１ or A ２２ Preferably, one of the groups represents nitrogen, another represents carbon, and the others each independently represent nitrogen or carbon. １１ or A ２２ It is preferable that one of the carbons in the formula (G1) is bonded to the formula (G1), and the others are bonded to any of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. １１ or A ２２ Among the substituents bonded to A, adjacent groups may be bonded to each other to form a ring. １２ and A １３In this case, the general formula (G1-1) includes five or more six-membered rings. １１ or A ２２ The same applies to the general formulae (G1-2) to (G1-6) described later. １１ or A ２２ It can also be said that the ring structure further includes two of the rings.

[0054]

[0055] In addition, in the general formula (G1-2), A ４１ or A ４８ It is preferred that any one of A represents carbon, and the others each independently represent nitrogen or carbon. ４１ or A ４８ It is preferable that one of the carbons in the formula (G1) is bonded to the formula (G1), and the others are each independently bonded to any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ４１ or A ４８ Among the substituents bonded to, adjacent groups may be bonded to each other to form a ring.

[0056] In addition, in the general formula (G1-3), A ５１ or A ６０ It is preferred that any one of A represents carbon, and the others each independently represent nitrogen or carbon. ５１ or A ６０ It is preferable that one of the carbons in the formula (G1) is bonded to the formula (G1), and the others are each independently bonded to any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ５１ or A ６０ Among the substituents bonded to, adjacent groups may be bonded to each other to form a ring.

[0057] In addition, in general formula (G1-4), A ６１ or A ６８ It is preferred that any one of A represents carbon, and the others each independently represent nitrogen or carbon. ６９ preferably represents nitrogen, carbon, sulfur or oxygen. ６１ or A ６８ Carbon or A ６９ It is preferable that one of the nitrogens in the formula (G1) is bonded to the formula (G1), and the others each independently represent any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ６１ or A ６８ Among the substituents bonded to, adjacent groups may be bonded to each other to form a ring.

[0058] In addition, in the general formula (G1-5), A ７１ or A ８０ It is preferred that any one of A represents carbon, and the others each independently represent nitrogen or carbon. ７１ or A ８０ It is preferable that one of the carbons in the general formula (G1) is bonded to the general formula (G1), and the others each independently represent any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ７１ or A ８０ Among the substituents bonded to, adjacent groups may be bonded to each other to form a ring.

[0059] In addition, in general formula (G1-6), A ８１ or A ９２ It is preferred that any one of A represents carbon, and the others each independently represent nitrogen or carbon. ８１ or A ９２It is preferable that one of the carbons in the general formula (G1) is bonded to the general formula (G1), and the others each independently represent any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ８１ or A ９２ Among the substituents bonded to, adjacent groups may be bonded to each other to form a ring.

[0060] Further, an organic compound of one embodiment of the present invention is an organic compound represented by the following general formula (G2).

[0061]

[0062] In general formula (G2), R ３ ~R ７ , A １ or A ３ The above configuration can be used.

[0063] Also, R ８ ~R １７ are preferably each independently any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. ８ ~R １７ Among these, adjacent groups may be bonded to each other to form a ring.

[0064] Further, an organic compound of one embodiment of the present invention is an organic compound represented by the following general formula (G3).

[0065]

[0066] In general formula (G3), R １ ~R ７ , A １ or A ３ The above configuration can be used.

[0067] Also, R １８ ~R ２１are preferably each independently any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. １８ ~R ２１ In the above, adjacent groups may be bonded to each other to form a ring. m represents 1 or 2. ４ The bonding position of may be any of the meta, para, and ortho positions, but the meta position allows the sublimation temperature to be lowered, and the para position allows the Tg to be increased.

[0068] Further, an organic compound of one embodiment of the present invention is an organic compound represented by the following general formula (G4).

[0069]

[0070] In general formula (G4), R １ ~R ７ , A １ or A ３ The above configuration can be used.

[0071] Also, R １８ ~R ２５ are preferably each independently any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. １８ ~R ２５ In the above, adjacent groups may be bonded to each other to form a ring. m represents 1 or 2. n represents 1 or 2. R ３ and R ４ The bonding position of may be any of the meta, para, and ortho positions, but the meta position allows the sublimation temperature to be lowered, and the para position allows the Tg to be increased.

[0072] The compound of one embodiment of the present invention preferably has a glass transition temperature Tg of 100° C. or higher. The compound of one embodiment of the present invention preferably has a glass transition temperature Tg of 120° C. or higher, preferably 130° C. or higher, more preferably 140° C. or higher, even more preferably 150° C. or higher, and particularly preferably 160° C. or higher.

[0073] Furthermore, the compound of one embodiment of the present invention preferably has a solubility of 0% or more and less than 5%. In this specification, the solubility (wt%) is evaluated as follows: When solute A (g) and solvent B (g) are placed in a glass container, if no precipitate is observed by visual inspection, the solubility is determined to be (A / (A+B)×100)% or more, and if a precipitate is observed, the solubility is determined to be less than (A / (A+B)×100)%.

[0074] In addition, A in the above general formulae (G1) to (G4) １ or A ９２ or R １ ~R ２５ The above structures (substituent structures, molecular weights, etc.) may be combined and applied to the above. For example, "R ３ and R ４ each having three or more condensed rings, and R ４ "A contains nitrogen" and "A １ or A ３ are all nitrogen atoms, and R １ and R ２ It is preferable to combine the composition with a composition in which the molecular weight of the polymer is 70 or more. By appropriately combining a plurality of compositions, not limited to this example, synergistic effects can be obtained, such as an improvement in the glass transition temperature Tg, an improvement in stability, and an improvement in the stability of the film quality in a thin film state.

[0075] In the above general formulae (G1) to (G4), specific examples of the alkyl group having 1 to 10 carbon atoms 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 sec-hexyl group, a tert-hexyl group, a neohexyl group, a 3-methylpentyl group, a 2-methylpentyl group, a 2-ethylbutyl group, a 1,2-dimethylbutyl group, and a 2,3-dimethylbutyl group.

[0076] In addition, in the above general formulae (G1) to (G4), specific examples of the substituted or unsubstituted aryl group having 6 to 60 carbon atoms and the substituted or unsubstituted heteroaryl group having 2 to 50 carbon atoms include a substituted or unsubstituted phenyl group, a biphenyl group, a terphenyl group, a fluorenyl group, a spirobifluorenyl group, a naphthyl group, an anthracenyl group, a phenanthryl group, a fluoranthenyl group, a pyrenyl group, a chrysenyl group, a triphenylenyl group, a perylenyl group, an indenyl group, a benzoindenyl group, a pyrrolyl group, and an indolyl group. Examples of the substituent include a group, a carbazolyl group, a furanyl group, a benzofuranyl group, a dibenzofuranyl group, a thiophenyl group, a benzothiophenyl group, a dibenzothiophenyl group, an imidazolyl group, a benzimidazolyl group, a triazolyl group, an oxazolyl group, an oxadiazolyl group, a thiazolyl group, a thiadiazolyl group, a pyrazolyl group, a pyridyl group, a pyrimidyl group, a pyridazyl group, a triazinyl group, a quinolinyl group, an indolocarbazolyl group, a benzocarbazolyl group, a quinoxalinyl group, or a dibenzoquinoxalinyl group. The bonding position may be any position if possible. More specifically, the substituents represented by (R-1) to (R-112) are preferred. The substituents represented by (R-1) to (R-112) may further have a substituent.

[0077]

[0078]

[0079]

[0080]

[0081]

[0082] When the compound according to one embodiment of the present invention is used in a light-emitting device, it is preferably formed into a thin film (also referred to as an organic compound layer). A thin film containing the organic compound according to one embodiment of the present invention can be suitably used in a charge adjustment layer, a charge generation layer, a light-emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, or a capping layer in a light-emitting device. The organic compound according to one embodiment of the present invention can also be used in a non-light-emitting device. Examples of non-light-emitting devices include light-receiving devices.

[0083] Note that a detailed structure of a light-emitting device or a light-receiving device using the organic compound of one embodiment of the present invention will be described in detail in Embodiment 2 or the like, which will be described later.

[0084] Next, specific examples of organic compounds which have the structures represented by any of the above general formulas (G1) to (G4) and which are embodiments of the present invention and which can be used in light-emitting devices are shown below.

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112]

[0113]

[0114] Various reactions can be applied as a method for synthesizing a compound of one embodiment of the present invention. For example, a compound of one embodiment of the present invention represented by General Formula (G1) can be synthesized by carrying out the synthesis reaction shown below. Note that the synthesis method for the compound of one embodiment of the present invention is not limited to the synthesis method shown below.

[0115] <<Method for Synthesizing Compound Represented by General Formula (G1)>> In this embodiment, a method for synthesizing an organic compound represented by the following general formula (G1) will be described.

[0116]

[0117] In general formula (G1), A １ or A ３or R １ ~R ７ The above-mentioned elements or substituents can be applied to the group.

[0118] The organic compound represented by General Formula (G1) can be synthesized according to the following synthesis schemes (a-1) to (a-5).

[0119] First, according to reaction formula (a-1), a compound 1 having an azine skeleton and R １ Compound 3 can be obtained by coupling Compound 2 having R ２ Compound 5 can be obtained by coupling Compound 4 having R ３ Compound 9 can be obtained by coupling compound 8 having R ４ By coupling with a compound 10 having the following formula:

[0120]

[0121] In the synthesis schemes (a-1) to (a-5), A １ or A ３ or R １ ~R ７ The above-mentioned elements or substituents can be applied to the group.

[0122] In the synthesis schemes (a-1) to (a-5), X １ ~X ５ represents a halogen group (including, for example, chlorine). １ ~B ５ represents boronic acid. However, the present invention is not limited to these. １ ~X ５ and B １ ~B ５may each independently represent chlorine, bromine, iodine, a triflate group, an organic boron group, boronic acid, an organic aluminum group, an organic zirconium group, an organic zinc group, an organic tin group, or the like. ３ and R ４ When X has a different substituent structure, ４ and X ５ Preferably, one of X is chlorine and the other is bromine or iodine. ４ and X ５ By using chlorine for one of the groups and bromine or iodine for the other, the coupling reaction of the group containing bromine or iodine proceeds preferentially, and therefore it becomes possible to obtain the compound represented by general formula (G1) in high yield and high purity. ３ and R ４ are the same substituent structure, X ４ and X ５ are preferably the same halogen, or each independently represents bromine or iodine. In this case, the compound of general formula (G1) can be obtained from compound 7 in one step by reacting two equivalents of compound 8 with compound 7.

[0123] The synthesis schemes (a-1) to (a-5) can be carried out, for example, by the Suzuki-Miyaura coupling reaction. In this case, examples of the palladium catalyst include palladium(II) acetate, tetrakis(triphenylphosphine)palladium(0), and bis(triphenylphosphine)palladium(II) dichloride. Examples of the ligand for the palladium catalyst include tri(ortho-tolyl)phosphine, triphenylphosphine, and tricyclohexylphosphine.

[0124] Examples of bases that can be used in the reactions of the synthetic schemes (a-1) to (a-5) include organic bases such as sodium tert-butoxide, and inorganic bases such as potassium carbonate, sodium carbonate, potassium phosphate, and potassium acetate.

[0125] Examples of solvents that can be used in the reactions of the synthetic schemes (a-1) to (a-5) include a mixed solvent of toluene and water, a mixed solvent of an alcohol and water such as toluene and ethanol, a mixed solvent of xylene and water, a mixed solvent of an alcohol and water such as xylene and ethanol, a mixed solvent of benzene and water, a mixed solvent of an alcohol and water such as benzene and ethanol, a mixed solvent of an ether and water such as diethylene glycol dimethyl ether, etc. A mixed solvent of toluene and water or a mixed solvent of toluene, ethanol and water, or a mixed solvent of an ether and water such as diethylene glycol dimethyl ether is more preferred.

[0126] However, the palladium catalyst, ligand, base and solvent may be other than those mentioned above.

[0127] Also, R １ ~R ７ may be deuterium. １ or A ３ or R １ ~R ７ may have a deuterium group. In that case, the coupling reaction may be carried out using a compound obtained by deuterating Compound 1, Compound 2, Compound 4, Compound 6, Compound 8, or Compound 10. Examples of solvents that can be used in the deuteration reaction include benzene-d6, toluene-d8, xylene-d10, and heavy water. Examples of catalysts that can be used include molybdenum chloride (V), tungsten chloride (VI), niobium chloride (V), tantalum chloride (V), aluminum chloride (III), titanium chloride (IV), and tin chloride (IV). However, the solvent and catalyst are not limited to these.

[0128] For example, in general formula (G1), R ３ is an aryl group, and R ４ ~R ７ When preparing a compound in which X is hydrogen, ６ is a halogen (including, for example, chlorine) and X ７ ~X １０ Compound 11, in which R is hydrogen, can be coupled with compound 12. ３ and R ４is an aryl group, and R ５ ~R ７ When preparing a compound in which X is hydrogen, ６ and X ７ is a halogen and X ８ ~X １０ is hydrogen, and then coupling is performed with Compound 12 and Compound 13. Compound 11 can be synthesized in the same manner as Compound 7, using Reaction Formulas (a-1) to (a-3) of Synthesis Method 1.

[0129] X ６ ~X １０ , and B ６ ~B １０ each independently represents hydrogen, chlorine, bromine, iodine, a triflate group, an organoboron group, boronic acid, an organoaluminum group, an organozirconium group, an organozinc group, an organotin group, or the like.

[0130] The conditions (palladium catalyst, solvent, etc.) used in the coupling reaction can be the same as those shown in reaction formulas (a-1) to (a-5).

[0131] The compounds represented by the general formula (G2) or (G3) can also be synthesized by the same synthesis method.

[0132] Some of the compounds represented by structural formulas (100) to (450) produced by the above synthesis method will be described below as examples. Of course, even for compounds not described as examples, the above substituents (R-1) to (R-112) can be replaced by R in reaction formulas (a-1) to (a-5). １ ~R ７ , or (b-1) R １ ~R ７ can be prepared by appropriately coupling to

[0133] The above synthesis method is an example, and the compound of the present invention can also be produced using other synthesis methods.

[0134] Embodiment Mode 2 In this embodiment mode, a structure of a light-emitting device using the organic compound shown in Embodiment Mode 1 will be described with reference to FIGS. 1A to 1E. FIG.

[0135] <<Basic Structure of Light-Emitting Device>> The basic structure of a light-emitting device will be described. Fig. 1A shows a light-emitting device having an EL layer including a light-emitting layer between a pair of electrodes. Specifically, the light-emitting device has a structure in which an EL layer 103 is sandwiched between a first electrode 101 and a second electrode 102.

[0136] 1B shows a light-emitting device with a stacked structure (tandem structure) having multiple (two in FIG. 1B) EL layers (103a, 103b) between a pair of electrodes, with a charge generation layer 106 between the EL layers. A light-emitting device with a tandem structure can realize a highly efficient light-emitting device without changing the amount of current.

[0137] The charge generation layer 106 has a function of injecting electrons into one EL layer (103a or 103b) and injecting holes into the other EL layer (103b or 103a) when a potential difference is generated between the first electrode 101 and the second electrode 102. Therefore, in Fig. 1B, 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 EL layer 103a and holes are injected into the EL layer 103b.

[0138] From the viewpoint of light extraction efficiency, the charge generation layer 106 preferably has transparency 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 lower conductivity than the first electrode 101 and the second electrode 102. The compound of the present application can also be used in the layer into which electrons are injected in the charge generation layer. In this case, it is preferable to use a mixed layer or a laminated structure of the compound of the present application with Li metal or a Li compound such as lithium oxide.

[0139] FIG. 1C also shows a stacked structure of the EL layer 103 of the 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 EL layer 103 has a structure in which a hole injection layer 111, a hole transport layer 112, a light-emitting layer 113, an electron transport layer 114, and an electron injection layer 115 are sequentially stacked over the first electrode 101. The light-emitting layer 113 may have a stacked structure of multiple light-emitting layers that emit different colors. For example, a light-emitting layer containing a red light-emitting substance, a light-emitting layer containing a green light-emitting substance, and a light-emitting layer containing a blue light-emitting substance may be stacked, or may have a structure in which the layers are stacked with a layer containing a carrier transport material interposed therebetween. 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 be configured by stacking multiple light-emitting layers emitting the same light color. 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 may be stacked, or a layer containing a carrier transport material may be interposed between the layers. A configuration in which multiple light-emitting layers emitting the same light color are stacked may provide higher reliability than a single-layer configuration. Even in a tandem structure such as that shown in FIG. 1B , in which multiple EL layers are included, each EL layer is stacked sequentially from the anode side as described above. Furthermore, when the first electrode 101 is a cathode and the second electrode 102 is an anode, the stacking order of the EL layer 103 is reversed. Specifically, the structure includes an electron injection layer 111 on the first electrode 101 (cathode), an electron transport layer 112, an emitting layer 113, a hole transport layer 114, and a hole injection layer 115.

[0140] The light-emitting layers 113 included in the EL layers (103, 103a, 103b) each contain a light-emitting substance and an appropriate 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 also 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. Alternatively, a structure in which different emission colors are emitted from the multiple EL layers (103a, 103b) shown in FIG. 1B 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.

[0141] In addition, in a light-emitting device that is one embodiment of the present invention, for example, the first electrode 101 shown in FIG. 1C 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. This allows light emission from the light-emitting layer 113 included in the EL layer 103 to resonate between the two electrodes, thereby enhancing the light emission emitted from the second electrode 102.

[0142] In addition, when the first electrode 101 of the light-emitting device is a reflective electrode having a laminated structure of a reflective conductive material and a light-transmitting conductive material (transparent conductive film), optical adjustment can be performed by controlling the film thickness of the transparent conductive film. Specifically, it is preferable to adjust the optical distance (product of film thickness and refractive index) between the first electrode 101 and the second electrode 102 to mλ / 2 (where m is an integer of 1 or greater) or in the vicinity thereof, for the wavelength λ of light obtained from the light-emitting layer 113.

[0143] Furthermore, 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 be (2m'+1)λ / 4 (where m' is an integer of 1 or more) or close to that. Note that the light-emitting region referred to here refers to a recombination region of holes and electrons in the light-emitting layer 113.

[0144] By performing such optical adjustment, the spectrum of the specific monochromatic light obtained from the light-emitting layer 113 can be narrowed, and light emission with good color purity can be obtained.

[0145] However, in the above case, the optical distance between the first electrode 101 and the second electrode 102 can be strictly defined as the total thickness from the reflective region of the first electrode 101 to the reflective region of the second electrode 102. However, since it is difficult to precisely determine the reflective regions of the first electrode 101 and the second electrode 102, the above-mentioned effect can be sufficiently achieved by assuming any position of the first electrode 101 and the second electrode 102 as the reflective region. Furthermore, the optical distance between the first electrode 101 and the light-emitting layer from which desired light is obtained can be strictly defined as the optical distance between the reflective region of the first electrode 101 and the light-emitting region of the light-emitting layer from which desired light is obtained. However, since it is difficult to precisely determine the reflective region of the first electrode 101 and the light-emitting region of the light-emitting layer from which desired light is obtained, the above-mentioned effect can be sufficiently achieved by assuming any position of the first electrode 101 as the reflective region and any position of the light-emitting layer from which desired light is obtained as the light-emitting region.

[0146] The light-emitting device shown in FIG. 1D is a light-emitting device with a tandem structure and a microcavity structure, which allows light of different wavelengths (monochromatic light) to be extracted from each EL layer (103a, 103b). Therefore, separate coloring (e.g., RGB) to obtain different emitted colors is not required. This makes it easy to achieve high definition. It can also be combined with a colored layer (color filter). Furthermore, it is possible to increase the emission intensity of a specific wavelength in the front direction, thereby reducing power consumption.

[0147] The light-emitting device shown in FIG. 1E is an example of the tandem-structure light-emitting device shown in FIG. 1B. As shown in the figure, the light-emitting device has a structure in which three EL layers (103a, 103b, 103c) are stacked with charge-generating layers (106a, 106b) sandwiched between them. The three EL 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. Alternatively, the light-emitting layer 113a can be red, the light-emitting layer 113b can be blue, green, or yellow, and the light-emitting layer 113c can be red. Furthermore, the light-emitting layers 113a, 113b, and 113c can be fluorescent or phosphorescent. Furthermore, the light-emitting layer 113a, the light-emitting layer 113b, and the light-emitting layer 113c may each independently be a single light-emitting layer or may be a stacked light-emitting layer of two or more layers. For example, when the light-emitting layer 113a, the light-emitting layer 113b, and the light-emitting layer 113c are a stacked light-emitting layer of two or more layers, the light-emitting layer 113a may be blue, the light-emitting layer 113b may be a three-layer stack of red, yellow, and green, and the light-emitting layer 113c may be blue. For example, when the light-emitting layer 113a, the light-emitting layer 113b, and the light-emitting layer 113c are a stacked light-emitting layer of two or more layers, the light-emitting layer 113a may be blue, the light-emitting layer 113b may be a two-layer stack of red and yellow, and the light-emitting layer 113c may be blue. For example, when the light-emitting layer 113a, the light-emitting layer 113b, and the light-emitting layer 113c are stacked light-emitting layers of two or more layers, the light-emitting layer 113a may be blue, the light-emitting layer 113b may be a four-layer stack of red, yellow, yellow, and green light, and the light-emitting layer 113c may be blue. By stacking light-emitting layers of different colors in this manner, it is possible to obtain light emission with good color rendering properties. It is effective to use the compound of the present application in multiple EL layers.

[0148] In the light-emitting device according to one embodiment of the present invention, at least one of the first electrode 101 and the second electrode 102 is a light-transmitting electrode (such as a transparent electrode or a semi-transmitting / semi-reflective electrode). When the light-transmitting electrode is a transparent electrode, the visible light transmittance of the transparent electrode is set to 40% or more. When the semi-transmitting / semi-reflective electrode is used, the visible light reflectance of the semi-transmitting / semi-reflective electrode is set to 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 that the resistance is Ωcm or less.

[0149] 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 (a reflective electrode), the reflectivity of the reflective electrode for visible light is set to 40% or more and 100% or less, preferably 70% or more and 100% or less. −２ It is preferable that the resistance is Ωcm or less.

[0150] Although FIG. 1 illustrates a light-emitting device having a tandem structure, the compound of one embodiment of the present application can be used in a monochromatic tandem light-emitting device that does not require separate coating, or in a light-emitting device with a separate coating structure. The monochromatic tandem light-emitting device can also be used in a full-color display by combining it with a color filter or a color conversion layer.

[0151] <<Specific Structure of Light-Emitting Device>> Next, a specific structure of a light-emitting device according to one embodiment of the present invention will be described. Here, the description will be made with reference to FIG. 1D having a tandem structure. The same applies to the EL layer configuration of the single-structure light-emitting devices shown in FIGS. 1A and 1C. When the light-emitting device shown in FIG. 1D has a microcavity structure, the first electrode 101 is formed as a reflective electrode, and the second electrode 102 is formed as a semi-transparent and semi-reflective electrode. Therefore, the electrode 102 can be formed as a single layer or a stacked layer using a single or multiple desired electrode materials. The second electrode 102 is formed by selecting an appropriate material after the EL layer 103b is formed.

[0152] <First Electrode and Second Electrode> The materials forming the first electrode 101 and the second electrode 102 can be appropriately combined from the following materials as long as they fulfill the functions of both electrodes described above. For example, metals, alloys, electrically conductive compounds, and mixtures thereof can be appropriately used. Specific examples include In-Sn oxide (also referred to as ITO), In-Si-Sn oxide (also referred to as ITSO), In-Zn oxide, and In-W-Zn oxide. Other metals that can be used include 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), and neodymium (Nd), as well as alloys containing appropriate combinations of these metals. Other examples that can be used include elements belonging to Group 1 or 2 of the periodic table (e.g., lithium (Li), cesium (Cs), calcium (Ca), and strontium (Sr)) that are not listed above, rare earth metals such as europium (Eu) and ytterbium (Yb), and alloys containing appropriate combinations of these, as well as graphene.

[0153] 1D , when the first electrode 101 is an anode, the hole injection layer 111a and the hole transport layer 112a of the EL layer 103a are sequentially formed by vacuum deposition on the first electrode 101. After the EL layer 103a and the charge generation layer 106 are formed, the hole injection layer 111b and the hole transport layer 112b of the EL layer 103b are similarly sequentially formed on the charge generation layer 106.

[0154] <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 EL layer (103, 103a, 103b), and is a layer that contains an organic acceptor material and a material with high hole injection properties.

[0155] An organic acceptor material is a material that can generate holes in an organic compound by causing charge separation between the organic acceptor material and another organic compound whose LUMO level (Lowest Unoccupied Molecular Orbital) value is close to the HOMO level value. Therefore, as the organic acceptor material, compounds having an electron-withdrawing group (halogen group or cyano group), such as quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene derivatives, can be used. For example, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviated as F ４ Examples of organic acceptor materials that can be used include 2-(7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyren-2-ylidene)malononitrile, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviation: F6-TCCNNQ), and 2-(7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyren-2-ylidene)malononitrile. Among organic acceptor materials, compounds such as HAT-CN in which an electron-withdrawing group is bonded to a fused aromatic ring having multiple heteroatoms are particularly suitable because of their high acceptor properties and stable film quality against heat. In addition, [3]radialene derivatives having an electron-withdrawing group (particularly a halogen group such as a fluoro group or a cyano group) are preferred because they have extremely high electron-accepting properties. Specifically, α,α',α''-1,2,3-cyclopropanetriylidene tris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α,α',α''-1,2,3-cyclopropanetriylidene tris[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], α,α',α''-1,2,3-cyclopropanetriylidene tris[2,3,4,5,6-pentafluorobenzeneacetonitrile], etc. can be used.

[0156] As a material with high hole injection properties, oxides of metals belonging to Groups 4 to 8 of the periodic table (transition metal oxides such as molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, manganese oxide, etc.) can be used. Specific examples include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide, and rhenium oxide. Among the above, molybdenum oxide is preferred because it is stable in the air, has low hygroscopicity, and is easy to handle. In addition, phthalocyanine (abbreviated as H ２ Phthalocyanine compounds such as copper phthalocyanine (abbreviated as CuPc) or copper phthalocyanine (abbreviated as CuPc) can be used.

[0157] In addition to the above materials, low molecular weight compounds such as 4,4',4''-tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA), 4,4',4''-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTDATA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenylbiphenyl-4,4'-diamine (abbreviation: DNTPD), and 1,3,5-tris[ Aromatic amine compounds such as N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), 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), and 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1) can be used.

[0158] Also usable are polymer compounds (oligomers, dendrimers, polymers, etc.), 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), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviation: Poly-TPD). Alternatively, polymer compounds to which an acid has been added, such as poly(3,4-ethylenedioxythiophene) / polystyrenesulfonic acid (abbreviation: PEDOT / PSS) and polyaniline / polystyrenesulfonic acid (abbreviation: PAni / PSS), can also be used.

[0159] Furthermore, as the material with high hole injection properties, a mixed material containing a hole transport material and the above-mentioned organic acceptor material (electron accepting material) can also be used. In this case, electrons are extracted from the hole transport material by the organic acceptor material, generating holes in the hole injection layer 111, and the holes are injected into the light-emitting layer 113 via the hole transport layer 112. Note that the hole injection layer 111 may be formed as a single layer made of a mixed material containing the hole transport material and the organic acceptor material (electron accepting material), or may be formed by laminating the hole transport material and the organic acceptor material (electron accepting material) as separate layers.

[0160] The hole transport material has a hole mobility of 1×10 when the square root of the electric field strength [V / cm] is 600. −６ cm ２ A substance having a hole mobility of 1 / Vs or more is preferred. Note that other substances can also be used as long as they have a higher hole transporting property than electron transporting property.

[0161] As the hole-transporting material, a material with high hole-transporting properties such as a compound having a π-electron-rich heteroaromatic ring (for example, a carbazole derivative, a furan derivative, or a thiophene derivative) and an aromatic amine (an organic compound having an aromatic amine skeleton) is preferred. The compound of Embodiment 1 has a hole-transporting property, and therefore can also be used as the hole-transporting material.

[0162] Examples of the carbazole derivatives (organic compounds having a carbazole ring) include bicarbazole derivatives (for example, 3,3'-bicarbazole derivatives), aromatic amines having a carbazolyl group, and the like.

[0163] Specific examples of the bicarbazole derivatives (e.g., 3,3′-bicarbazole derivatives) include 3,3′-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP), 9,9′-bis(biphenyl-4-yl)-3,3′-bi-9H-carbazole (abbreviation: BisBPCz), 9,9′-bis(biphenyl-3-yl)-3,3′-bi-9H-carbazole (abbreviation: BismBPCz), 9-(biphenyl-3-yl)-9′-(biphenyl-4-yl)-9H,9′H-3,3′-bicarbazole (abbreviation: mBPCCBP), and 9-(2-naphthyl)-9′-phenyl-9H,9′H-3,3′-bicarbazole (abbreviation: βNCCP).

[0164] Specific examples of the aromatic amine having a carbazolyl group include 4-phenyl-4′-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 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), N-[ 4-(9-phenyl-9H-carbazol-3-yl)phenyl]-bis(9,9-dimethyl-9H-fluoren-2-yl)amine (abbreviation: PCBFF), N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-4-amine, N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-(9,9-dimethyl-9H-fluoren-2-yl)-9,9-dimethyl-9H-fluoren-4-amine, N-(biphenyl-4-yl)-N-[4- (9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-diphenyl-9H-fluoren-2-amine, N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-diphenyl-9H-fluoren-4-amine, N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9'-spirobi(9H-fluoren)-2-amine, N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]- N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-(1,1':3',1"-terphenyl-4-yl)-9,9-dimethyl-9H-fluoren-2-amine, N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-(1,1':4',1"-terphenyl-4-yl)-9,9-dimethyl-9H-fluoren-2-amine, N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-(1,1':3',N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-(1,1':4',1''-terphenyl-4-yl)-9,9-dimethyl-9H-fluoren-4-amine, 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: PCBBi1BP), : 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 (abbreviation: PCA3B), 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]spiro-9,9'-bifluoren-2-amine (abbreviation: PCBASF), 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenyl) 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA2), 3,Examples include 6-bis[N-(4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTPN2), 2-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: PCASF), 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-2,7-diamine (abbreviation: YGA2F), and 4,4',4''-tris(carbazol-9-yl)triphenylamine (abbreviation: TCTA).

[0165] In addition to the above, examples of the carbazole derivatives include 3-[4-(9-phenanthryl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPPn), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4′-di(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), and 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA).

[0166] Specific examples of the furan derivatives (organic compounds having a furan ring) include 4,4′,4″-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II) and 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II).

[0167] Specific examples of the thiophene derivatives (organic compounds having a thiophene ring) include 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), and 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV).

[0168] Specific examples of the aromatic amine include 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB or α-NPD), N,N′-bis(3-methylphenyl)-N,N′-diphenyl-biphenyl-4,4′-diamine (abbreviation: TPD), 4,4′-bis[N-(spiro-9,9′-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), 4-phenyl-4′-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3′-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), and 4-phenyl-3′-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP). 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 (abbreviation: DFLADFL), N-(9,9-dimethyl-2-diphenylamino-9H-fluoren-7-yl)diphenylamine (abbreviation: DPNF), 2-[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'- Bifluorene (abbreviation: DPASF), 2,7-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-spiro-9,9'-bifluorene (abbreviation: DPA2SF), 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' -di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), DNTPD, 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), N-(4-biphenyl)-6,N-diphenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf), 4,4′-bis(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)-4″-phenyltriphenylamine (abbreviation: BnfBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf(8) ), N,N-bis(4-biphenyl)benzo[b]naphtho[2,3-d]furan-4-amine (abbreviation: BBABnf(II)(4)), N,N-bis[4-(dibenzofuran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB1TP), N-[4-(dibenzothiophen-4-yl)phenyl]-N-phenyl-4-biphenylamine (abbreviation: ThBA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenylamine amine (abbreviation: BBAβNB), 4-[4-(2-naphthyl)phenyl]-4',4''-diphenyltriphenylamine (abbreviation: BBAβNBi), 4,4'-diphenyl-4''-(6;1'-binaphthyl-2-yl)triphenylamine (abbreviation: BBAαNβNB), 4,4'-diphenyl-4''-(7;1'-binaphthyl-2-yl)triphenylamine (abbreviation: BBAαNβNB-03), 4,4'-diphenyl-4''-(7-phenyl)naphthalene 4,4'-diphenyl-4''-(6;2'-binaphthyl-2-yl)triphenylamine (abbreviation: BBAPβNB-03), 4,4'-diphenyl-4''-(6;2'-binaphthyl-2-yl)triphenylamine (abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-(7;2'-binaphthyl-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diphenyl-4''-(4;2'-binaphthyl-1-yl)triphenylamine (abbreviation: BBAβNαNB), 4,4'-Diphenyl-4''-(5;2'-binaphthyl-1-yl)triphenylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenylyl)-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB), 4-(3-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: mTPBiAβNBi), 4-(4-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine nyl]-4"-phenyltriphenylamine (abbreviation: TPBiAβNBi), 4-phenyl-4'-(1-naphthyl)triphenylamine (abbreviation: αNBA1BP), 4,4'-bis(1-naphthyl)triphenylamine (abbreviation: αNBB1BP), 4,4'-diphenyl-4"-[4'-(carbazol-9-yl)biphenyl-4-yl]triphenylamine (abbreviation: YGTBi1BP), 4'-[4-(3-phenyl-9H-carbazol-9-yl )phenyl]tris(biphenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carbazol-9-yl)biphenyl-4-yl]-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBNBSF), N , N-bis(biphenyl-4-yl)-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: BBASF), N,N-bis(biphenyl-4-yl)-9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: BBASF(4)), N-(biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: oFBiSF), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)dibenzofuran-4-amine (abbreviation: FrBiF), N-[4-(1-naphthyl)phenyl]-N-[3-(6-phenyldibenzofuran-4-yl)phenyl]-1-naphthylamine (abbreviation: mPDBfBNBN), 4-phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine (abbreviation: BPAFLBi), N,N-bis(9, ... N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluoren-4-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluoren-3-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluoren-2-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluoren-1-amine, and the like are mentioned.

[0169] Other examples of hole-transporting materials that can be used include polymer compounds (oligomers, dendrimers, polymers, etc.) 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), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviation: Poly-TPD). Alternatively, polymer compounds to which an acid has been added, such as poly(3,4-ethylenedioxythiophene) / polystyrenesulfonic acid (abbreviation: PEDOT / PSS) and polyaniline / polystyrenesulfonic acid (abbreviation: PAni / PSS), can also be used.

[0170] However, the hole transporting material is not limited to the above, and various known materials may be used alone or in combination as the hole transporting material.

[0171] The hole injection layers (111, 111a, 111b) can be formed using various known film formation methods, for example, vacuum deposition.

[0172] <Hole transport layer> The hole transport layer (112, 112a, 112b) is a layer that transports holes injected from the first electrode 101 by the hole injection layer (111, 111a, 111b) to the light-emitting layer (113, 113a, 113b). The hole transport layer (112, 112a, 112b) is a layer that contains a hole transport material. Therefore, the hole transport layer (112, 112a, 112b) can be made of the same hole transport material that can be used for the hole injection layer (111, 111a, 111b).

[0173] In the light-emitting device of one embodiment of the present invention, the same organic compound as that of the hole-transport layer (112, 112a, 112b) can be used for the light-emitting layer (113, 113a, 113b, 113c). It is more preferable to use the same organic compound for the hole-transport layer (112, 112a, 112b) and the light-emitting layer (113, 113a, 113b, 113c) because holes can be efficiently transported from the hole-transport layer (112, 112a, 112b) to the light-emitting layer (113, 113a, 113b, 113c).

[0174] <Light-emitting layer> The light-emitting layers (113, 113a, 113b, 113c) are layers containing a light-emitting substance. Note that, as the light-emitting substance that can be used for the light-emitting layers (113, 113a, 113b, 113c), 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. Furthermore, when a plurality of light-emitting layers are provided, 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.

[0175] The light-emitting layers (113, 113a, 113b, 113c) may contain one or more organic compounds (host materials, etc.) in addition to the light-emitting substance (guest material).

[0176] When a plurality of host materials are used in the light-emitting layer (113, 113a, 113b, 113c), it is preferable to use a substance having a larger energy gap than the energy gaps of the existing guest material and the first host material as the newly added second host material. Furthermore, it is preferable that the lowest singlet excitation energy level (S1 level) of the second host material is higher than the S1 level of the first host material, and the lowest triplet excitation energy level (T1 level) of the second host material is higher than the T1 level of the guest material. Furthermore, it is preferable that the lowest triplet excitation energy level (T1 level) of the second host material is higher than the T1 level of the first host material. With this structure, an exciplex can be formed using two types of host materials. To efficiently form an exciplex, it is particularly preferable to combine a compound that easily accepts holes (hole-transporting material) with a compound that easily accepts electrons (electron-transporting material). Furthermore, this structure can simultaneously achieve high efficiency, low voltage, and long life.

[0177] As the organic compound used as the host material (including the first host material and the second host material), as long as it satisfies the conditions for a host material used in an emitting layer, examples thereof include organic compounds such as hole-transporting materials that can be used in the hole-transporting layer (112, 112a, 112b) described above, or electron-transporting materials that can be used in the electron-transporting layer (114, 114a, 114b) described below. The organic compound may also be an exciplex composed of multiple organic compounds (the first host material and the second host material described above). An exciplex (also referred to as an exciplex) that forms an excited state with multiple organic compounds has an extremely small difference between the S1 level and the T1 level and functions as a TADF material that can convert triplet excitation energy to singlet excitation energy. Furthermore, as a combination of multiple organic compounds that form an exciplex, for example, one of the compounds has a π-electron-deficient heteroaromatic ring and the other has a π-electron-rich heteroaromatic ring. As a combination for forming an exciplex, one of the compounds may be a phosphorescent material such as an iridium-, rhodium-, or platinum-based organometallic complex or a metal complex. The organic compounds described in Embodiment 1 have electron-transporting properties and can therefore be effectively used as the first host material. In addition, they have hole-transporting properties and can therefore also be used as the second host material.

[0178] The light-emitting substance that can be used in the light-emitting layer (113, 113a, 113b, 113c) is not particularly limited, and a light-emitting substance that converts singlet excitation energy into light emission in the visible light region, or a light-emitting substance that converts triplet excitation energy into light emission in the visible light region can be used.

[0179] <Light-emitting substance that converts singlet excitation energy into light emission> Examples of light-emitting substances that can be used in the light-emitting layers (113, 113a, 113b, 113c) and that convert singlet excitation energy into light emission include the following fluorescent substances (fluorescent light-emitting substances). Examples 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, and naphthalene derivatives. Pyrene derivatives are particularly preferred because of their high light emission quantum yield. Specific examples of the pyrene derivative include N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bis(dibenzofuran-2-yl)-N,N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6FrAPrn), and N,N'-bis(dibenzothiophen-2-yl)-N, Examples thereof include N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6ThAPrn), N,N'-(pyrene-1,6-diyl)bis[(N-phenylbenzo[b]naphtho[1,2-d]furan)-6-amine] (abbreviation: 1,6BnfAPrn), N,N'-(pyrene-1,6-diyl)bis[(N-phenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-02), and N,N'-(pyrene-1,6-diyl)bis[(6,N-diphenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03).

[0180] In addition, 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′-bis[4-(9H-carbazol-9-yl)phenyl]-N,N′-diphenylstilbene-4,4′-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)phenyl]- N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), 4-(10-phenyl-9-anthryl)-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), 4-(10-phenyl-9-anthryl)-4'- (9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), 4-[4-(10-phenyl-9-anthryl)phenyl]-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPBA), perylene, 2,5,8,11-tetra-tert-butylperylene (abbreviation: TBP), N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1-phenyl) N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), and the like can be used.

[0181] Further, N-[9,10-bis(biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(biphenyl-2-yl)-N-[ 4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracen-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracen-9-amine (abbreviation: DPhAPhA), Coumarin 545T, N,N'-diphenylquinacridone (abbreviation: DPQd), rubrene, 5,12-bis(biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyran-4-ylidene)propanedinit (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N',N'-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,10-diamine (abbreviation: p-mPhA FD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]ethenyl}-4H-pyran-4-ylidene)propanedinitrile (abbreviation: BisDCM), 2-{2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJ™), 1,6BnfAP rn-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. In particular, pyrene diamine compounds such as 1,6FLPAPrn, 1,6mMemFLPAPrn, and 1,6BnfAPrn-03 can be used.

[0182] <Light-Emitting Substance Converting Triplet Excitation Energy into Light Emission> Examples of light-emitting substances that convert triplet excitation energy into light emission and that can be used in the light-emitting layer 113 include phosphorescent substances (phosphorescent light-emitting substances) and thermally activated delayed fluorescence (TADF) materials that exhibit thermally activated delayed fluorescence.

[0183] A phosphorescent material refers to a compound that exhibits phosphorescence but does not exhibit fluorescence at a temperature range from low temperature (e.g., 77 K) to room temperature (i.e., 77 K to 313 K). The phosphorescent material preferably contains a metal element with a large spin-orbit interaction, such as an organometallic complex, a metal complex (platinum complex), or a rare earth metal complex. Specifically, a transition metal element is preferred, and a platinum group element (ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), or platinum (Pt)) is particularly preferred. Among these, iridium is preferred because it can increase the transition probability associated with the direct transition between the singlet ground state and the triplet excited state.

[0184] <Phosphorescent Substances (450 nm to 570 nm: Blue or Green)> Examples of phosphorescent substances that exhibit blue or green and have an emission spectrum with a peak wavelength of 450 nm to 570 nm include the following substances.

[0185] For example, tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN]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 ]), organometallic complexes having a 4H-triazole ring such as tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(Mptz1-mp) ３ ]), tris(1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Prptz1-Me) ３ organometallic complexes having a 1H-triazole ring such as fac-tris[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation: [Ir(iPrpmi) ３ ]), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: [Ir(dmpimpt-Me) ３]), organometallic complexes having an imidazole ring such as bis[2-(4',6'-difluorophenyl)pyridinato-N,C2']iridium(III) tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinato-N,C2']iridium(III) picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinato-N,C2']iridium(III) tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), ２’} Iridium(III) picolinate (abbreviation: [Ir(CF ３ ppy) ２ (pic)]), bis[2-(4',6'-difluorophenyl)pyridinato-N,C ２’ ] Examples include organometallic complexes having a phenylpyridine derivative having an electron-withdrawing group as a ligand, such as iridium(III) acetylacetonate (abbreviation: FIr(acac)).

[0186] <Phosphorescent Substances (495 nm or More and 590 nm or Less: Green or Yellow)> Examples of phosphorescent substances that exhibit green or yellow and have an emission spectrum with a peak wavelength of 495 nm or more and 590 nm or less include the following substances.

[0187] For example, 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[6-(2-norbornyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(nbppm) ２(acac)]), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(mpmppm) ２ (acac)]), (acetylacetonato)bis{4,6-dimethyl-2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN]phenyl-κC}iridium(III) (abbreviation: [Ir(dmppm-dmp) ２ (acac)]), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm) ２ organometallic iridium complexes having a pyrimidine ring, such as (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-Me) ２ (acac)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-iPr) ２ organometallic iridium complexes having a pyrazine ring, such as tris(2-phenylpyridinato-N,C(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’ ) iridium(III) acetylacetonate (abbreviation: [Ir(pq) ２(acac)]), bis[2-(2-pyridinyl-κN)phenyl-κC][2-(4-phenyl-2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: [Ir(ppy) ２ (4dppy)]), bis[2-(2-pyridinyl-κN)phenyl-κC][2-(4-methyl-5-phenyl-2-pyridinyl-κN)phenyl-κC], [2-d3-methyl-8-(2-pyridinyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(5-d3-methyl-2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviated as Ir(5mppy-d) ２ (mbfpypy-d3)), [2-(methyl-d3)-8-[4-(1-methylethyl-1-d)-2-pyridinyl-κN]benzofuro[2,3-b]pyridin-7-yl-κC]bis[5-(methyl-d3)-2-[5-(methyl-d3)-2-pyridinyl-κN]phenyl-κC]iridium(III) (abbreviation: Ir(5mtpy-d6) ２ (mbfpypy-iPr-d4)), [2-d3-methyl-(2-pyridinyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy) ２ (mbfpypy-d3)), [2-(4-methyl-5-phenyl-2-pyridinyl-κN)phenyl-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy) ２ organometallic iridium complexes having a pyridine ring, such as bis(2,4-diphenyl-1,3-oxazolato-N,C (mdppy)); 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’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(bt) ２In addition to organometallic complexes such as tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: [Tb(acac)]), ３ (Phen)]).

[0188] <Phosphorescent Substances (570 nm to 750 nm: Yellow or Red)> Examples of phosphorescent substances that exhibit yellow or red and have an emission spectrum with a peak wavelength of 570 nm to 750 nm include the following substances.

[0189] For example, (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)]), (dipivaloylmethanato)bis[4,6-di(naphthalen-1-yl)pyrimidinato]iridium(III) (abbreviation: [Ir(dpm)] ２ organometallic complexes having a pyrimidine ring 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)]), bis{4,6-dimethyl-2-[3-(3,5-dimethylphenyl)-5-phenyl-2-pyrazinyl-κN]phenyl-κC}(2,6-dimethyl-3,5-heptanedionato-κ ２ O,O')iridium(III) (abbreviation: [Ir(dmdppr-P) ２ (dibm)]), bis{4,6-dimethyl-2-[5-(4-cyano-2,6-dimethylphenyl)-3-(3,5-dimethylphenyl)-2-pyrazinyl-κN]phenyl-κC}(2,2,6,6-tetramethyl-3,5-heptanedionato-κ ２ O,O′)iridium(III) (abbreviation: [Ir(dmdppr-dmCP)２ (dpm)]), bis[2-(5-(2,6-dimethylphenyl)-3-(3,5-dimethylphenyl)-2-pyrazinyl-κN)-4,6-dimethylphenyl-κC](2,2′,6,6′-tetramethyl-3,5-heptanedionato-κO,O′)iridium(III) (abbreviation: [Ir(dmdppr-dmp) ２ (dpm)]), (acetylacetonato)bis[2-methyl-3-phenylquinoxalinato-N,C ２’ ]iridium(III) (abbreviation: [Ir(mpq) ２ (acac)]), (acetylacetonato)bis(2,3-diphenylquinoxalinato-N,C ２’ ) Iridium(III) (abbreviation: [Ir(dpq) ２ (acac)]), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq) ２ organometallic complexes having a pyrazine ring, such as tris(1-phenylisoquinolinato-N,C(acac)]), ２’ ) Iridium(III) (abbreviation: [Ir(piq) ３ ]), bis(1-phenylisoquinolinato-N,C ２’ ) iridium(III) acetylacetonate (abbreviation: [Ir(piq) ２ (acac)]), and bis[4,6-dimethyl-2-(2-quinolinyl-κN)phenyl-κC] (2,4-pentanedionato-κ ２ O,O')iridium(III) (abbreviation: [Ir(dmpqn) ２ (acac)]), platinum complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrinplatinum(II) (abbreviation: [PtOEP]), 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)]).

[0190] <TADF Material> The following materials can be used as the TADF material. A TADF material is a material that has a small difference between the S1 level and the T1 level (preferably 0.2 eV or less), can upconvert a triplet excited state to a singlet excited state with a small amount of thermal energy (reverse intersystem crossing), and efficiently emits light (fluorescence) from the singlet excited state. Conditions for efficiently obtaining thermally activated delayed fluorescence include an energy difference between the triplet excited energy level and the singlet excited energy level of 0 eV or more and 0.2 eV or less, preferably 0 eV or more and 0.1 eV or less. The delayed fluorescence in a TADF material refers to light emission that has a spectrum similar to that of ordinary fluorescence but has a significantly long lifetime. Its lifetime is 1 x 10 −６ seconds or more, or 1 x 10 −３ The organic compound described in Embodiment Mode 1 can be used.

[0191] The TADF material can also be used as an electron transporting material, a hole transporting material, or a host material.

[0192] Examples of TADF materials include fullerene and its derivatives, acridine derivatives such as proflavine, and eosin. Also, examples of metal-containing porphyrins include those containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (Pd). Examples of metal-containing porphyrins include protoporphyrin-tin fluoride complexes (abbreviated as SnF ２ (Proto IX)), mesoporphyrin-tin fluoride complex (abbreviation: SnF ２ (Meso IX)), hematoporphyrin-tin fluoride complex (abbreviation: SnF ２ (Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (abbreviation: SnF ２ (Copro III-4Me)), octaethylporphyrin-tin fluoride complex (abbreviation: SnF ２(OEP)), etioporphyrin-tin fluoride complex (abbreviation: SnF ２ (EtioI)), octaethylporphyrin-platinum chloride complex (abbreviation: PtCl ２ OEP) and the like.

[0193]

[0194] Other 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-phenoxy) 3-[4-(5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthen-9-one (abbreviation: ACRXTN), bis[4-(9, 9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracen]-10'-one (abbreviation: ACRSA), 4-(9'-phenyl-3,3'-bi-9H-carbazol-9-yl)benzofuro[3,2-d]pyrimidine (abbreviation: 4PCCzBfpm), 4-[4-(9'-phenyl-3,3'- Heteroaromatic compounds having a π-electron rich heteroaromatic compound and a π-electron deficient heteroaromatic compound, such as 9-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9′-phenyl-2,3′-bi-9H-carbazole (abbreviation: mPCCzPTzn-02), may also be used.

[0195] In addition, a substance in which a π-electron-rich heteroaromatic compound and a π-electron-deficient heteroaromatic compound are directly bonded is particularly preferable because the donor property of the π-electron-rich heteroaromatic compound and the acceptor property of the π-electron-deficient heteroaromatic compound are both strong, and the energy difference between the singlet excited state and the triplet excited state is small. Furthermore, a TADF material (TADF100) in which the singlet excited state and the triplet excited state are in thermal equilibrium may be used as the TADF material. Such a TADF material has a short emission lifetime (excitation lifetime), which can suppress a decrease in efficiency in the high-brightness region of a light-emitting device.

[0196]

[0197] In addition to the above, examples of materials capable of converting triplet excitation energy into luminescence include nanostructures of transition metal compounds having a perovskite structure. Nanostructures of metal halide perovskites are particularly preferred. Nanoparticles and nanorods are preferred as such nanostructures.

[0198] In the light-emitting layers (113, 113a, 113b, 113c), one or more substances having an energy gap larger than the energy gap of the light-emitting substance (guest material) may be selected and used as the organic compound (host material or the like) used in combination with the above-mentioned light-emitting substance (guest material).

[0199] <Fluorescent Host Material> When the light-emitting substance used in the light-emitting layer (113, 113a, 113b, 113c) is a fluorescent light-emitting substance, it is preferable to use, as the organic compound (host material) to be combined, an organic compound having a high energy level in a singlet excited state and a low energy level in a triplet excited state, or an organic compound with a high fluorescence quantum yield. Therefore, as long as the organic compound satisfies these conditions, the hole-transporting material (described above) and the electron-transporting material (described below) shown in this embodiment can be used. In addition, the organic compounds described in Embodiment 1 can be used.

[0200] Although some of the examples overlap with those described above, examples of the organic compound (host material) from the viewpoint of a preferable combination with the light-emitting substance (fluorescent light-emitting substance) include condensed polycyclic aromatic compounds such as anthracene derivatives, tetracene derivatives, phenanthrene derivatives, pyrene derivatives, chrysene derivatives, and dibenzo[g,p]chrysene derivatives.

[0201] Specific examples of organic compounds (host materials) that are preferably used in combination with fluorescent materials include 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: DPCzPA), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 9,10-diphenylanthracene (abbreviation: DPAnth), N,N-diphenylanthracene (abbreviation: DPAnth), and N,N-diphenylanthracene (abbreviation: DPAnth). N-nyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: CzA1PA), 4-(10-phenyl-9-anthryl)triphenylamine (abbreviation: DPhPA), YGAPA, PCAPA, N,9-diphenyl-N-{4-[4-(10-phenyl-9-anthryl)phenyl]phenyl}-9H-carbazole-3-amine (abbreviation: PCAPBA), N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCAPA), 6,12-dimethoxy-5,11-diphenylchrysene, N,N,N',N',N'',N'',N''',N'''-octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), 7-[4-(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgDBCzPA), 6-[3-(9,10-diphenyl-2-anthryl)phenyl]-benzyl benzo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl-10-{4-(9-phenyl-9H-fluoren-9-yl)-biphenyl-4'-yl}-anthracene (abbreviation: FLPPA), 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 9-(1-naphthyl)-10-(2-naphthyl)anthracene (abbreviation: α,β-ADN), 2-(10-phenylanthracen-9-yl)dibenzofuran, 2-(10-phenyl-9-anthracenyl)-benzo[b]naphtho[2,3-d]furan (abbreviation: Bnf(II)PhA), 9-(1-naphthyl)-10-[4-(2-naphthyl)phenyl]anthracene (abbreviation: αN-βNPAnth), 2,9-di(1-naphthyl)-10-phenylanthracene (abbreviation: 2αN-αNPhA), 9-(1-naphthyl)-10-[3-(1-naphthyl)phenyl]anthracene (abbreviation: αN-mαNPAnth), 9-(2-naphthyl)-10-[3-(1-naphthyl)phenyl]anthracene (abbreviation: βN-mαNPAnth), 9-(1-naphthyl)-10-[4-(1-naphthyl)phenyl]anthracene (abbreviation: αN-αNPAnth), 9-(2-naphthyl)-10-[4-(2-naphthyl)phenyl] Anthracene (abbreviation: βN-βNPAnth), 2-(1-naphthyl)-9-(2-naphthyl)-10-phenylanthracene (abbreviation: 2αN-βNPhA), 9-(2-naphthyl)-10-[3-(2-naphthyl)phenyl]anthracene (abbreviation: βN-mβNPAnth), 1-[4-(10-(biphenyl-4-yl)-9-anthracenyl)phenyl]-2-ethyl-1H-benzimidazole (abbreviation: EtB ImPBPhA), 9,9'-bianthryl (abbreviation: BANT), 9,9'-(stilbene-3,3'-diyl)diphenanthrene (abbreviation: DPNS), 9,9'-(stilbene-4,4'-diyl)diphenanthrene (abbreviation: DPNS2), 1,3,5-tri(1-pyrenyl)benzene (abbreviation: TPB3), 5,12-diphenyltetracene, 5,12-bis(biphenyl-2-yl)tetracene, etc.

[0202] <Phosphorescent Host Material> When the light-emitting substance used in the light-emitting layers (113, 113a, 113b, and 113c) is a phosphorescent substance, an organic compound having a triplet excitation energy greater than the triplet excitation energy (energy difference between the ground state and the triplet excited state) of the light-emitting substance can be selected as the organic compound (host material) to be combined. When a plurality of organic compounds (e.g., a first host material and a second host material (or assist material)) are used in combination with the light-emitting substance to form an exciplex, it is preferable to mix these plurality of organic compounds with the phosphorescent substance. The organic compounds described in Embodiment 1 can also be used.

[0203] With this structure, light emission can be efficiently obtained using Exciplex-Triple Energy Transfer (ExTET), which is energy transfer from an exciplex to a light-emitting substance. It is preferable to combine a plurality of organic compounds that easily form an exciplex, and it is particularly preferable to combine a compound that easily accepts holes (hole transport material) with a compound that easily accepts electrons (electron transport material).

[0204] Although some of the organic compounds (host materials, assist materials) overlap with the above-mentioned specific examples, from the viewpoint of a preferable combination with the light-emitting substance (phosphorescent light-emitting substance), examples thereof include aromatic amines (organic compounds having an aromatic amine skeleton), carbazole derivatives (organic compounds having a carbazole ring), dibenzothiophene derivatives (organic compounds having a dibenzothiophene ring), dibenzofuran derivatives (organic compounds having a dibenzofuran ring), oxadiazole derivatives (organic compounds having an oxadiazole ring), triazole derivatives (organic compounds having a triazole ring), benzimidazole derivatives (benzoin derivatives), and the like. midazole ring), quinoxaline derivatives (organic compounds having a quinoxaline ring), dibenzoquinoxaline derivatives (organic compounds having a dibenzoquinoxaline ring), pyrimidine derivatives (organic compounds having a pyrimidine ring), triazine derivatives (organic compounds having a triazine ring), pyridine derivatives (organic compounds having a pyridine ring), bipyridine derivatives (organic compounds having a bipyridine ring), phenanthroline derivatives (organic compounds having a phenanthroline ring), furodiazine derivatives (organic compounds having a furodiazine ring), zinc- and aluminum-based metal complexes, and the like.

[0205] Among the organic compounds, specific examples of the aromatic amine and carbazole derivative, which are organic compounds with high hole-transporting properties, include the same as the specific examples of the hole-transporting material described above, and any of these is preferable as the host material.

[0206] Specific examples of the dibenzothiophene derivatives and dibenzofuran derivatives, which are organic compounds with high hole transport properties among the above organic compounds, include 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II), 4,4′,4″-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II), DBT3P-II, 2,8-dipheny Examples of such compounds include 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV), and 4-[3-(triphenylen-2-yl)phenyl]dibenzothiophene (abbreviation: mDBTPTp-II), all of which are preferable as the host material.

[0207] Other preferred host materials include metal complexes having an oxazole-based or thiazole-based ligand, such as bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO) and bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ).

[0208] Specific examples of the organic compounds having high electron transport properties, such as oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, quinazoline derivatives, and phenanthroline derivatives, among the above organic compounds, include 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), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), 4,4'-bis(5-methylphenyl)-1H-benzoimidazole (abbreviation: mDBTBIm-II), organic compounds containing heteroaromatic rings with polyazole rings, such as benzoxazol-2-yl)stilbene (abbreviation: BzOs), bathophenanthroline (abbreviation: Bphen), bathocuproine (abbreviation: BCP), 2,9-di(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBphen), 2,2'-(1,3-phenylene)bis(9-phenyl-1,10-phenanthroline) (abbreviation: mPPhen2P), 2,2'-(1,1'-biphenyl)-4,4'-diylbis(9-phenyl-1,10- phenanthroline) (abbreviation: PPhen2BP), 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-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDB q-II), 2-{4-[9,10-di(2-naphthyl)-2-anthryl]phenyl}-1-phenyl-1H-benzimidazole (abbreviation: ZADN), 2-[4′-(9-phenyl-9H-carbazol-3-yl)-3,1′-biphenyl-1-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mpPCBPDBq), and the like, all of which are preferred as host materials.

[0209] Specific examples of the pyridine derivatives, diazine derivatives (including pyrimidine derivatives, pyrazine derivatives, and pyridazine derivatives), triazine derivatives, and furodiazine derivatives, which are organic compounds with high electron transport properties among the above organic compounds, include 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), and 4,6-bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II). 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 9-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTzn-02), 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1,3 ,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB), 9,9'-[pyrimidine-4,6-diylbis(biphenyl-3,3'-diyl)]bis(9H-carbazole) (abbreviation: 4,6mCzBP2Pm), 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFBPTzn), 8-(biphenyl-4-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d ]pyrimidine (abbreviation: 8BP-4mDBtPBfpm), 9-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9mDBtBPNfpr), 9-[3'-(dibenzothiophen-4-yl)biphenyl-4-yl]naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9pmDBtBPNfpr), 11-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]phenanthro[9',10':4,5]furo[2,3-b]pyrazine (abbreviation: 11mDBtBPPnfpr), 11-[3'-(dibenzothiophen-4-yl)biphenyl-4-yl]phenanthro[9',10':4,5]furo[2,3-b]pyrazine, 11-[(3'-(9H-carbazol-9-yl)biphenyl-3-yl]phenanthro[9',10':4,5]furo[2,3-b]pyrazine, 12-(9'-phenyl-3,3'-bi-9H-carbazol-9-yl)phenanthro[9',10':4,5]furo[2,3-b]pyrazine (abbreviation: 12PCCzPnfpr), 9-[(3'-9 -phenyl-9H-carbazol-3-yl)biphenyl-4-yl]naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9pmPCBPNfpr), 9-(9'-phenyl-3,3'-bi-9H-carbazol-9-yl)naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9PCCzNfpr), 10-(9'-phenyl-3,3'-bi-9H-carbazol-9-yl)naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 10PCCzNfpr), 9-[3'-(6-phenylbenzo[b]naphtho [1,2-d]furan-8-yl)biphenyl-3-yl]naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9mBnfBPNfpr), 9-{3-[6-(9,9-dimethylfluoren-2-yl)dibenzothiophen-4-yl]phenyl}naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9mFDBtPNfpr), 9-[3'-(6-phenyldibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9mDBtBPNfpr-02), 9-{3-[6-(9,9-dimethylfluoren-2-yl)dibenzothiophen-4-yl]phenyl}naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9mFDBtPNfpr-02), -[3-(9'-phenyl-3,3'-bi-9H-carbazol-9-yl)phenyl]naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9mPCCzPNfpr), 9-{(3'-[2,8-diphenyldibenzothiophen-4-yl]biphenyl-3-yl}naphtho[1',2':4,5]furo[2,3-b]pyrazine, 11-{(3'-[2,8-diphenyldibenzothiophen-4-yl]biphenyl-3-yl}phenanthro[9',10':4,5]furo[2,3-b]pyrazine, 5-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]carbazole (abbreviation: mINc(II)PTzn), 2-[3′-(triphenylen-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mTpBPTzn), 2-(biphenyl-4-yl)-4-phenyl-6-[9,9′-spirobi(9H-fluorene)- 2-yl]-1,3,5-triazine (abbreviation: BP-SFTzn), 2,6-bis(4-naphthalen-1-ylphenyl)-4-[4-(3-pyridyl)phenyl]pyrimidine (abbreviation: 2,4NP-6PyPPm), 9-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)-2-dibenzothienyl]-2-phenyl-9H-carbazole (abbreviation: PCzDBfTzn), 3-[9-(4, 6-diphenyl-1,3,5-triazin-2-yl)-2-dibenzofuranyl]-9-phenyl-9H-carbazole (abbreviation: PCDBfTzn), 2-biphenyl-3-yl-4-phenyl-6-(8-[1,1':4',1''-terphenyl]-4-yl-1-dibenzofuranyl)-1,3,5-triazine (abbreviation: mBP-TPDBfTzn), 6-(biphenyl-3-yl)-4-[3,5- and organic compounds containing a heteroaromatic ring having a diazine ring, such as 4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), 4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenyl-6-(biphenyl-4-yl)pyrimidine (abbreviation: 6BP-4Cz2PPm), all of which are preferred as host materials.

[0210] Specific examples of metal complexes, which are organic compounds with high electron transport properties among the above organic compounds, include zinc-based or aluminum-based metal complexes such as tris(8-quinolinolato)aluminum(III) (abbreviation: Alq) and tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviation: Almq). ３ ), bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq ２), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), as well as metal complexes having a quinoline ring or a benzoquinoline ring, and the like, all of which are preferable as the host material.

[0211] Other preferred host materials include polymer compounds such as poly(2,5-pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviation: PF-Py), and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2′-bipyridine-6,6′-diyl)] (abbreviation: PF-BPy).

[0212] Furthermore, bipolar 9-phenyl-9′-(4-phenyl-2-quinazolinyl)-3,3′-bi-9H-carbazole (abbreviation: PCCzQz), 2-[4′-(9-phenyl-9H-carbazol-3-yl)-3,1′-biphenyl-1-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mpPCBPDBq), 5-[3-(4,6-diphenyl-1,3,5-triazin-2yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2 ,1-b]carbazole (abbreviation: mINc(II)PTzn), 11-[4-(biphenyl-4-yl)-6-phenyl-1,3,5-triazin-2-yl]-11,12-dihydro-12-phenyl-indolo[2,3-a]carbazole (abbreviation: BP-Icz(II)Tzn), or 7-[4-(9-phenyl-9H-carbazol-2-yl)quinazolin-2-yl]-7H-dibenzo[c,g]carbazole (abbreviation: PC-cgDBCzQz) can also be used as the host material.

[0213] <Electron Transport Layer> The electron transport layers (114, 114a, 114b) are layers that transport electrons injected from the second electrode 102 and the charge generation layers (106, 106a, 106b) by the electron injection layers (115, 115a, 115b) described later to the light-emitting layers (113, 113a, 113b, 113c). Note that the heat resistance of the light-emitting device according to one embodiment of the present invention can be improved by the electron transport layer having a stacked structure. In addition, the electron transport material used for the electron transport layers (114, 114a, 114b) has an electron mobility of 1×10 or more at a square root of an electric field strength [V / cm] of 600. −６ cm ２ A substance having an electron mobility of 1 / Vs or higher is preferred. Note that other substances can be used as long as they have a higher electron transporting property than holes. The electron transport layer (114, 114a, 114b) functions as a single layer, but may also have a stacked structure of two or more layers. Note that the above mixed materials have heat resistance, and therefore, by performing a photolithography process on the electron transport layer using such a mixed material, the influence of a thermal process on the device characteristics can be suppressed.

[0214] <Electron Transporting Material> As the electron transporting material that can be used for the electron transporting layers (114, 114a, 114b), an organic compound with high electron transporting properties can be used, such as a heteroaromatic compound. A heteroaromatic compound is a cyclic compound containing at least two different elements in the ring. The ring structure includes a three-membered ring, a four-membered ring, a five-membered ring, a six-membered ring, and the like, with a five-membered ring or a six-membered ring being particularly preferred. The element contained therein is preferably a heteroaromatic compound containing one or more of nitrogen, oxygen, sulfur, and the like in addition to carbon. Heteroaromatic compounds containing nitrogen (nitrogen-containing heteroaromatic compounds) are particularly preferred, and it is preferable to use a material with high electron transporting properties (electron transporting material), such as a nitrogen-containing heteroaromatic compound or a π-electron-deficient heteroaromatic compound containing the same. The compound of Embodiment 1 has electron transporting properties and can therefore be used as an electron transporting material. It is even more preferable to use the compound of the present invention in both the electron transporting layer 114a and the electron transporting layer 114b.

[0215] The electron transport material may be a material different from the material used in the light-emitting layer. Not all excitons generated by carrier recombination in the light-emitting layer can contribute to light emission, and they may diffuse to layers adjacent to or located nearby the light-emitting layer. To avoid this phenomenon, it is preferable that the energy level (lowest singlet excitation energy level or lowest triplet excitation energy level) of the material used in the layer adjacent to or located nearby the light-emitting layer is higher than that of the material used in the light-emitting layer. Therefore, by using a material different from the material used in the light-emitting layer as the electron transport material, a highly efficient light-emitting device can be obtained.

[0216] A heteroaromatic compound is an organic compound that contains at least one heteroaromatic ring.

[0217] The heteroaromatic ring has any one of a pyridine ring, a diazine ring, a triazine ring, a polyazole ring, an oxazole ring, a thiazole ring, etc. The heteroaromatic ring having a diazine ring includes a heteroaromatic ring having a pyrimidine ring, a pyrazine ring, a pyridazine ring, etc. The heteroaromatic ring having a polyazole ring includes a heteroaromatic ring having an imidazole ring, a triazole ring, or an oxadiazole ring.

[0218] The heteroaromatic ring also includes a fused heteroaromatic ring having a fused ring structure, such as a quinoline ring, a benzoquinoline ring, a quinoxaline ring, a dibenzoquinoxaline ring, a quinazoline ring, a benzoquinazoline ring, a dibenzoquinazoline ring, a phenanthroline ring, a phlodiazin ring, or a benzimidazole ring.

[0219] Among heteroaromatic compounds containing one or more of nitrogen, oxygen, and sulfur in addition to carbon, examples of heteroaromatic compounds having a five-membered ring structure include heteroaromatic compounds having an imidazole ring, heteroaromatic compounds having a triazole ring, heteroaromatic compounds having an oxazole ring, heteroaromatic compounds having an oxadiazole ring, heteroaromatic compounds having a thiazole ring, and heteroaromatic compounds having a benzimidazole ring.

[0220] Furthermore, among heteroaromatic compounds containing one or more of nitrogen, oxygen, and sulfur in addition to carbon, examples of heteroaromatic compounds having a six-membered ring structure include heteroaromatic compounds having a heteroaromatic ring such as a pyridine ring, a diazine ring (including a pyrimidine ring, a pyrazine ring, and a pyridazine ring), a triazine ring, and a polyazole ring.Heteroaromatic compounds having a structure in which pyridine rings are linked include heteroaromatic compounds having a bipyridine structure and heteroaromatic compounds having a terpyridine structure.

[0221] Furthermore, examples of heteroaromatic compounds having a fused ring structure partially containing the above-mentioned 6-membered ring structure include heteroaromatic compounds having a fused heteroaromatic ring such as a quinoline ring, a benzoquinoline ring, a quinoxaline ring, a dibenzoquinoxaline ring, a phenanthroline ring, a furodiazine ring (including a structure in which an aromatic ring is fused to the furan ring of a furodiazine ring), and a benzimidazole ring.

[0222] Specific examples of the heteroaromatic compound having a five-membered ring structure (such as a polyazole ring (including an imidazole ring, a triazole ring, and an oxadiazole ring), an oxazole ring, a thiazole ring, and a benzimidazole ring) include 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-furan (abbreviation: OXD-7 ... phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: p-EtTAZ), 2,2′,2″-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), 4,4′-bis(5-methylbenzoxazol-2-yl)stilbene (abbreviation: BzOs), and the like.

[0223] Specific examples of the heteroaromatic compound having a 6-membered ring structure (including a heteroaromatic ring having a pyridine ring, a diazine ring, a triazine ring, or the like) include heteroaromatic compounds having a pyridine ring, 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); 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl- 1,3,5-triazine (abbreviation: PCCzPTzn), 9-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTzn-02), 5-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]carbazole (abbreviation: mINc(II)PTzn), 2-[3'-(triphenylen-2-yl)-biphenyl-3-yl]-4,6-diphenyl-1,3,5- triazine (abbreviation: mTpBPTzn), 2-(biphenyl-4-yl)-4-phenyl-6-[9,9'-spirobi(9H-fluoren)-2-yl]-1,3,5-triazine (abbreviation: BP-SFTzn), 2,6-bis(4-naphthalen-1-ylphenyl)-4-[4-(3-pyridyl)phenyl]pyrimidine (abbreviation: 2,4NP-6PyPPm), 9-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)-2-dibenzothienyl]-2-phenyl-9H-carbazole (abbreviation: PCzDBfTzn), 3-[9-( 4,6-diphenyl-1,3,5-triazin-2-yl)-2-dibenzofuranyl]-9-phenyl-9H-carbazole (abbreviation: PCDBfTzn), 2-(biphenyl-3-yl)-4-phenyl-6-(8-[1,1':4',1''-terphenyl]-4-yl-1-dibenzofuranyl)-1,3,5-triazine (abbreviation: mBP-TPDBfTzn), 2-{3-[3-(dibenzothiophen-4-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mDBtBPTzn), 2-[3'-(9,heteroaromatic compounds containing a heteroaromatic ring having a triazine ring, such as [9-dimethyl-9H-fluoren-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFBPTzn), 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6-bis[3-(9H-carbazol-9-yl) phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm), 4,6mCzBP2Pm, 6-(biphenyl-3-yl)-4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), 4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenyl-6-(1,1'-biphenyl-4-yl)pyrimidine (abbreviation: 6BP-4Cz2PPm), 4-[3-(dibenzothiophen-4-yl)phenyl]-8-( naphthalen-2-yl)-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8βN-4mDBtPBfpm), 8BP-4mDBtPBfpm, 9mDBtBPNfpr, 9pmDBtBPNfpr, 3,8-bis[3-(dibenzothiophen-4-yl)phenyl]benzofuro[2,3-b]pyrazine (abbreviation: 3,8mDBtP2Bfpr), 4,8-bis[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 4,8mDBtP2B Examples of heteroaromatic compounds include those containing a heteroaromatic ring having a diazine (pyrimidine) ring, such as 8-[3'-(dibenzothiophen-4-yl)(biphenyl-3-yl)]naphtho[1',2':4,5]furo[3,2-d]pyrimidine (abbreviation: 8mDBtBPNfpm), 8-[(2,2'-binaphthalen)-6-yl]-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8(βN2)-4mDBtPBfpm), and the like. The aromatic compounds containing heteroaromatic rings include heteroaromatic compounds having fused heteroaromatic rings.

[0224] Other examples include 2,2'-(pyridine-2,6-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 2,6(P-Bqn)2Py), 2,2'-(2,2'-bipyridine-6,6'-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 6,6'(P-Bqn)2BPy), 2,2'-(pyridine-2,6-diyl)bis{4-[4-(2-naphthyl)phenyl]-6-phenylpyrimidine} (abbreviation: 2,6(NP-PPm)2Py), and 6-(biphenyl-3-yl)-4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP). heteroaromatic compounds containing a heteroaromatic ring having a diazine (pyrimidine) ring, such as 2,4,6-tris(3′-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine (abbreviation: TmPPPyTz), 2,4,6-tris(2-pyridyl)-1,3,5-triazine (abbreviation: 2Py3Tz), and 2-[3-(2,6-dimethyl-3-pyridyl)-5-(9-phenanthrenyl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mPn-mDMePyPTzn); and heteroaromatic compounds containing a heteroaromatic ring having a triazine ring, such as 2,4,6-tris(3′-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine (abbreviation: TmPPPyTz).

[0225] Specific examples of the heteroaromatic compound having a fused ring structure partially containing a 6-membered ring structure (heteroaromatic compound having a fused ring structure) include bathophenanthroline (abbreviation: Bphen), bathocuproine (abbreviation: BCP), 2,9-di(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBphen), 2,2′-(1,3-phenylene)bis(9-phenyl-1,10-phenanthroline), 2,2'-(1,1'-biphenyl)-4,4'-diylbis(9-phenyl-1,10-phenanthroline) (abbreviation: PPhen2BP), 2,2'-(pyridine-2,6-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 2,6(P-Bqn)2Py), 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2m DBTPDBq-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-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 2mpPCBPDBq, and other heteroaromatic compounds having a quinoxaline ring.

[0226] In addition to the heteroaromatic compounds described above, the electron transport layers (114, 114a, 114b) may also include the following metal complexes: tris(8-quinolinolato)aluminum(III) (abbreviation: Alq ３ ), Almq ３ , 8-quinolinolatolithium (I) (abbreviation: Liq), BeBq ２metal complexes having a quinoline ring or a benzoquinoline ring, such as bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq) and bis(8-quinolinolato)zinc(II) (abbreviation: Znq); and metal complexes having an oxazole ring or a thiazole ring, such as bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO) and bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ).

[0227] Furthermore, polymer compounds such as poly(2,5-pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-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 as the electron transport material.

[0228] The electron transport layer (114, 114a, 114b) may have not only a single layer structure but also a structure in which two or more layers made of the above-mentioned substances are stacked.

[0229] <Electron injection layer> The electron injection layer (115, 115a, 115b) is a layer containing a substance with high electron injection properties. The electron injection layer (115, 115a, 115b) is a layer for increasing the efficiency of electron injection from the second electrode 102, and it is preferable to use a material having a small difference (0.5 eV or less) between the work function value of the material used for the second electrode 102 and the LUMO level value of the material used for the electron injection layer (115, 115a, 115b). Therefore, the electron injection layer 115 is preferably made of lithium, cesium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ２ ), Liq, 2-(2-pyridyl)phenolatolithium (abbreviation: LiPP), 2-(2-pyridyl)-3-pyridinolatolithium (abbreviation: LiPPy), 4-phenyl-2-(2-pyridyl)phenolatolithium (abbreviation: LiPPP), lithium oxide (LiO ｘ), alkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used. Also, erbium fluoride (ErF ３ A rare earth metal or a rare earth metal compound such as ytterbium (Yb) or ytterbium (Yb) can be used. The electron injection layer (115, 115a, 115b) may be formed by mixing a plurality of the above materials or by stacking a plurality of the above materials. The electron injection layer (115, 115a, 115b) may also be formed by using an electride. Examples of the electride include a substance in which a mixed oxide of calcium and aluminum is doped with a high concentration of electrons. The substance constituting the electron transport layer (114, 114a, 114b) described above can also be used. The compound of the present application has excellent electron injection properties and is therefore suitable for use in the electron injection layer. It is even more suitable to use the compound of the present application in both the electron injection layer 115a and the electron injection layer 115b.

[0230] The electron injection layer (115, 115a, 115b) may also be formed using a mixed material comprising an organic compound and an electron donor (donor). Such a mixed material has excellent electron injection and electron transport properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material that is excellent at transporting the generated electrons. Specifically, the electron transport materials (metal complexes, heteroaromatic compounds, etc.) used in the electron transport layer (114, 114a, 114b) described above 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, and rare earth metals are preferred, such as lithium, cesium, magnesium, calcium, erbium, and ytterbium. Alkali metal oxides and alkaline earth metal oxides are preferred, such as lithium oxide, calcium oxide, and barium oxide. Lewis bases such as magnesium oxide can also be used. Organic compounds such as tetrathiafulvalene (abbreviated as TTF) can also be used. Furthermore, a plurality of these materials may be laminated.

[0231] Alternatively, the electron injection layer (115, 115a, 115b) may be made of a mixed material obtained by mixing an organic compound and a metal. The organic compound used here preferably has a LUMO level of −3.6 eV or more and −2.3 eV or less. A material having an unshared electron pair is also preferred.

[0232] Therefore, the organic compound used in the mixed material may be a mixed material obtained by mixing a heteroaromatic compound with a metal, as described above as being usable in the electron transport layer. Preferred heteroaromatic compounds include heteroaromatic compounds having a five-membered ring structure (such as an imidazole ring, a triazole ring, an oxazole ring, an oxadiazole ring, a thiazole ring, or a benzimidazole ring), heteroaromatic compounds having a six-membered ring structure (such as a pyridine ring, a diazine ring (including a pyrimidine ring, a pyrazine ring, or a pyridazine ring), a triazine ring, a bipyridine ring, or a terpyridine ring), and heteroaromatic compounds having a fused ring structure partially including a six-membered ring structure (such as a quinoline ring, a benzoquinoline ring, a quinoxaline ring, a dibenzoquinoxaline ring, or a phenanthroline ring). Specific materials are described above, and therefore will not be described here.

[0233] As the metal used in the mixed material, it is preferable to use a transition metal belonging to Group 5, Group 7, Group 9 or Group 11 in the periodic table and a material belonging to Group 13, such as Ag, Cu, Al or In. In this case, the organic compound forms a Singly Occupied Molecular Orbital (SOMO) with the transition metal.

[0234] For example, when light obtained from the light-emitting layer 113b is to be amplified, the optical distance between the second electrode 102 and the light-emitting layer 113b is preferably less than ¼ of the wavelength λ of light emitted by the light-emitting layer 113b. In this case, the optical distance can be adjusted by changing the film thickness of the electron-transporting layer 114b or the electron-injecting layer 115b.

[0235] Furthermore, as in the light-emitting device shown in FIG. 1D, by providing a charge generation layer 106 between two EL layers (103 a, 103 b), a structure in which multiple EL layers are stacked between a pair of electrodes (also referred to as a tandem structure) can be formed.

[0236] <Charge Generation Layer> The charge generation layer 106 has a function of injecting electrons into the EL layer 103a and injecting holes into the EL 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 referred to as a P-type layer) or a structure in which an electron donor is added to an electron-transporting material (also referred to as an electron injection buffer layer). Alternatively, 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. Forming the charge generation layer 106 using the above-described material can suppress an increase in driving voltage when EL layers are stacked. The compound of the present application has excellent transport properties, making it suitable for use in the charge generation layer 106.

[0237] In the case where the charge generation layer 106 has a structure (a 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. ４ -TCNQ), chloranil, etc. Also, oxides of metals belonging to Groups 4 to 8 of the periodic table can be used. Specific examples include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide. The acceptor materials described above may also be used. Furthermore, a mixed film obtained by mixing materials constituting the P-type layer may be used, or single films containing each material may be stacked.

[0238] In addition, when the charge generation layer 106 has a structure in which 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, as the electron donor, 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, or an oxide or carbonate thereof can be used. Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide (Li ２ It is preferable to use cesium carbonate, cesium carbonate, etc. Also, an organic compound such as tetrathianaphthacene may be used as the electron donor.

[0239] When 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 the 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 higher, preferably −5.0 eV or higher and −3.0 eV or lower. Note that the substance having electron transport properties used in the electron relay layer is preferably a phthalocyanine-based material or a metal complex having a metal-oxygen bond and an aromatic ligand.

[0240] Although FIG. 1D shows a structure in which the EL layer 103 has two stacked layers, a stacked structure of three or more EL layers may be used by providing a charge generating layer between different EL layers.

[0241] <Capping Layer> Although not shown in FIGS. 1A to 1E , 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 may be used for the capping layer. By providing a capping layer on the second electrode 102, the extraction efficiency of light emitted from the second electrode 102 can be improved. The refractive index of the capping layer material is preferably higher than that of the electron transport layer material. Furthermore, the refractive index of the capping layer material is preferably higher than that of the electron transport layer material, higher than that of the host material of the light-emitting layer, and higher than that of the hole transport layer material. The capping layer may also have a laminated structure. In this case, it is preferable to laminate a layer containing the compound of the present application and an upper layer containing a material with a refractive index higher than that of the compound of the present application.

[0242] Furthermore, in a bendable device (also referred to as a flexible device) using a flexible substrate as a substrate, the bends may result in a decrease in light extraction efficiency or a decrease in luminous efficiency due to the influence of external light. Therefore, it is preferable to use a material with a high refractive index as a cap layer in the bends. More specifically, it is preferable to arrange a cap layer, a cathode, a layer containing the compound of the present application, and an emitting layer in a stacked manner in the bends. In this case, it is preferable that the refractive index of the compound of the present application is smaller than the refractive index of the cap layer material and the refractive index of the host material of the emitting layer. Furthermore, in a device having multiple bends or a winding-type device, since there are many bends, it is preferable to arrange a cap layer, a layer containing the compound of the present application, and an emitting layer in a stacked manner in the bends.

[0243] Furthermore, the LUMO level of the electron transport layer material is preferably at least 0.3 eV lower than the LUMO level of the cap layer material, more preferably at least 0.5 eV lower. Furthermore, the LUMO level of the host material of the light-emitting layer is preferably at least 0.1 eV higher than the LUMO level of the cap layer material, more preferably at least 0.3 eV higher. In particular, the LUMO level relationship is preferably cap layer material > light-emitting layer host material > electron transport layer material. When multiple light-emitting devices (e.g., red device, blue device, green device) are provided, it is preferable that the LUMO level relationship be satisfied in each light-emitting device.

[0244] Specific examples of materials that can be used for the capping 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. Furthermore, compounds having a triarylamine skeleton are preferred because they are highly stable. From the viewpoint of stability, it is also effective to use compounds having a triarylamine skeleton for both the capping layer and the hole injection layer. Alternatively, it is also preferable to use compounds having a triarylamine skeleton for all of the capping layer, the hole injection layer, and the hole transport layer. The organic compounds described in Embodiment 1 can also be used.

[0245] <Substrate> The light-emitting device described in this embodiment can be formed on various substrates. Note that the type of substrate is not limited to a specific one. Examples of the substrate include a semiconductor substrate (for example, 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 stainless steel foil, a tungsten substrate, a substrate having tungsten foil, a flexible substrate, a laminated film, paper containing a fibrous material, or a base film.

[0246] Examples of glass substrates include barium borosilicate glass, aluminoborosilicate glass, soda lime glass, etc. Examples of flexible substrates, laminated films, base films, etc. include plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyethersulfone (PES), synthetic resins such as acrylic resins, polypropylene, polyester, polyvinyl fluoride, polyvinyl chloride, polyamide, polyimide, aramid, epoxy resins, inorganic vapor deposition films, and papers.

[0247] Note that the light-emitting device described in this embodiment can be fabricated using a gas phase method such as vapor deposition, a spin coating method, or a liquid phase method such as an inkjet method. When a vapor deposition method is used, a physical vapor deposition (PVD) method such as sputtering, ion plating, ion beam deposition, molecular beam deposition, or vacuum deposition, a chemical vapor deposition (CVD) method, or the like can be used. In particular, layers having various functions included in the EL layer of the light-emitting device (hole injection layer 111, hole transport layer 112, light-emitting layer 113, electron transport layer 114, and electron injection layer 115) can be formed by a vapor deposition method (vacuum deposition, etc.), a coating method (dip coating, die coating, bar coating, spin coating, spray coating, etc.), a printing method (inkjet printing, screen (stencil printing), offset (lithographic printing), flexography (relief printing), gravure printing, microcontact printing, etc.), or the like.

[0248] When applying a film formation method such as the coating method or printing method, it is possible to use high molecular weight compounds (oligomers, dendrimers, polymers, etc.), medium molecular weight compounds (compounds in the intermediate range between low molecular weight and high molecular weight: molecular weight of 400 to 4000), inorganic compounds (quantum dot materials, etc.), etc. As the quantum dot material, it is possible to use colloidal quantum dot materials, alloy type quantum dot materials, core-shell type quantum dot materials, core type quantum dot materials, etc.

[0249] The materials for the layers (hole injection layer 111, hole transport layer 112, light-emitting layer 113, electron transport layer 114, and electron injection layer 115) constituting the EL layer 103 of the light-emitting device described in this embodiment mode are not limited to those described in this embodiment mode, and other materials can be used in combination as long as they can fulfill the functions of the respective layers.

[0250] In this specification and the like, the terms "layer" and "film" can be used interchangeably as appropriate.

[0251] The compound according to one embodiment of the present application can be used as a hole-transporting material, a host material, an electron-transporting material, a capping layer, or the like.

[0252] The structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiments.

[0253] In this embodiment, a light-emitting and receiving device 700 will be described as an example of a specific configuration example and a manufacturing method of the light-emitting and receiving device according to one embodiment of the present invention. Note that the light-emitting and receiving device 700 can be called a light-emitting device because it includes a light-emitting device, and can be called a light-receiving device because it includes a light-receiving device. Furthermore, since the light-emitting and receiving device 700 can be applied to a display portion of an electronic device or the like, it can also be called a display panel or a display device.

[0254] 2A includes a light-emitting and receiving device 700 including a light-emitting device 550B, a light-emitting device 550G, a light-emitting device 550R, and a light-receiving device 550PS. The light-emitting device 550B, the light-emitting device 550G, the light-emitting device 550R, and the light-receiving device 550PS are formed on a functional layer 520 provided on a first substrate 510. The functional layer 520 includes driving circuits such as a gate driver and a source driver each composed of a plurality of transistors, as well as wiring and the like that electrically connects these. These driving circuits are, for example, electrically connected to the light-emitting device 550B, the light-emitting device 550G, the light-emitting device 550R, and the light-receiving device 550PS, respectively, and can drive these devices. The light emitting and receiving device 700 also includes an insulating layer 705 on the functional layer 520 and each device (light emitting device and light receiving device), and the insulating layer 705 functions to bond the second substrate 770 and the functional layer 520 together.

[0255] Light-emitting device 550B, light-emitting device 550G, and light-emitting device 550R have the device structure shown in Embodiment 2, and light-receiving device 550PS has the device structure described later in Embodiment 8. In this embodiment, the case where each device (plurality of light-emitting devices and light-receiving devices) is formed separately has been described. However, part of the EL layer of the light-emitting device (hole injection layer, hole transport layer, and electron transport layer) and part of the active layer of the light-receiving device (first transport layer and second transport layer) may be formed simultaneously from the same material in the manufacturing process. This will be described in detail in Embodiment 8.

[0256] In this specification and the like, a structure in which the light-emitting layers of the light-emitting devices of each color (e.g., blue (B), green (G), and red (R)) and the light-receiving layers of the light-receiving devices are separately fabricated or separately painted may be referred to as an SBS (Side By Side) structure. In the light-receiving and light-emitting device 700 shown in FIG. 2A , the light-emitting device 550B, the light-emitting device 550G, the light-emitting device 550R, and the light-receiving device 550PS are arranged in this order, but one embodiment of the present invention is not limited to this configuration. For example, in the light-receiving and light-emitting device 700, these devices may be arranged in the order of the light-emitting device 550R, the light-emitting device 550G, the light-emitting device 550B, and the light-receiving device 550PS.

[0257] In FIG. 2A , light-emitting device 550B has electrodes 551B, 552, and EL layer 103B. Light-emitting device 550G has electrodes 551G, 552, and EL layer 103G. Light-emitting device 550R has electrodes 551R, 552, and EL layer 103R. Light-receiving device 550PS has electrodes 551PS, 552, and light-receiving layer 103PS. The specific configuration of each layer of the light-receiving device is as shown in Embodiment 8. The specific configuration of each layer of the light-emitting device is as shown in Embodiment 2. EL layers 103B, 103G, and 103R have a stacked structure consisting of multiple layers with different functions, including light-emitting layers (105B, 105G, and 105R). Light-receiving layer 103PS has a stacked structure consisting of multiple layers with different functions, including active layer 105PS. 2A illustrates the case where the EL layer 103B has a hole injection / transport layer 104B, a light-emitting layer 105B, an electron transport layer 108B, and an electron injection layer 109; the EL layer 103G has a hole injection / transport layer 104G, a light-emitting layer 105G, an electron transport layer 108G, and an electron injection layer 109; the EL layer 103R has a hole injection / transport layer 104R, a light-emitting layer 105R, an electron transport layer 108R, and an electron injection layer 109; and the light-receiving layer 103PS has a first transport layer 104PS, an active layer 105PS, a second transport layer 108PS, and an electron injection layer 109; however, the present invention is not limited to this. The hole injection / transport layers (104B, 104G, 104R) are layers having the functions of the hole injection layer and the hole transport layer shown in Embodiment 2, and may have a laminated structure.

[0258] The electron transport layers (108B, 108G, 108R) and the second transport layer 108PS may have a function of blocking holes that move from the anode side through the light-emitting layers (103B, 103G, 103R) and the light-receiving layer 103PS of the light-receiving device to the cathode side. The electron injection layer 109 may have a laminated structure formed of a part or all of different materials.

[0259] 2A , an insulating layer 107 may be formed on the side surfaces (or edges) of the hole injection / transport layers (104B, 104G, 104R), the light-emitting layers (105B, 105G, 105R), and the electron transport layers (108B, 108G, 108R) of the EL layers (103B, 103G, 103R), and on the side surfaces (or edges) of the first transport layer 104PS, the active layer 105PS, and the second transport layer 108PS of the light-receiving layer 103PS. The insulating layer 107 is formed in contact with the side surfaces (or edges) of the EL layers (103B, 103G, 103R) and the light-receiving layer 103PS. This prevents oxygen, moisture, or their constituent elements from penetrating into the EL layers (103B, 103G, 103R) and the light-receiving layer 103PS from their side surfaces. The insulating layer 107 can be formed using, for example, aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indium gallium zinc oxide, silicon nitride, or silicon nitride oxide. The insulating layer 107 may also be formed by stacking the above-mentioned materials. The insulating layer 107 can be formed by sputtering, CVD, MBE, PLD, ALD, or other methods, but ALD is preferred due to its excellent coverage. The insulating layer 107 has a structure that continuously covers part of the EL layers (103B, 103G, and 103R) of adjacent light-emitting devices or part of the side surfaces (or ends) of the light-receiving layer 103PS of the light-receiving device. For example, in FIG. 2A , part of the EL layer 103B of the light-emitting device 550B and part of the side surfaces of the EL layer 103G of the light-emitting device 550G are covered by the insulating layer 107. In addition, it is preferable that a partition wall 528 made of an insulating material be formed in the region covered with the insulating layer 107 as shown in FIG. 2A.

[0260] An electron injection layer 109 is formed on the electron transport layers (108B, 108G, 108R) that are part of the EL layers (103B, 103G, 103R), the second transport layer 108PS that is part of the light-receiving layer 103PS, and the insulating layer 107. The electron injection layer 109 may have a stacked structure of two or more layers (for example, a stack of layers with different electrical resistances).

[0261] The electrode 552 is formed on the electron injection layer 109. The electrodes (551B, 551G, 551R) and the electrode 552 overlap each other in some areas. The light-emitting layer 105B is located between the electrode 551B and the electrode 552, the light-emitting layer 105G is located between the electrode 551G and the electrode 552, the light-emitting layer 105R is located between the electrode 551R and the electrode 552, and the light-receiving layer 103PS is located between the electrode 551PS and the electrode 552.

[0262] 2A (103B, 103G, 103R) have the same configuration as the EL layer 103 described in embodiment 2. The light-receiving layer 103PS has the same configuration as the light-receiving layer described later in embodiment 8. For example, the light-emitting layer 105B can emit blue light, the light-emitting layer 105G can emit green light, and the light-emitting layer 105R can emit red light.

[0263] A partition wall 528 is provided in a region surrounded by the electron injection layer 109 and the insulating layer 107. As shown in Fig. 2A , the electrodes (551B, 551G, 551R, 551PS) of each light-emitting device, parts of the EL layers (103B, 103G, 103R), and parts of the light-receiving layer 103PS are in contact with the partition wall 528 at their sides (or ends) via the insulating layer 107.

[0264] In each EL layer and light-receiving layer, the hole injection layer included in the hole transport region located between the anode and the light-emitting layer and between the anode and the active layer often has high conductivity, and therefore, if it is formed as a layer common to adjacent devices, it may cause crosstalk. Therefore, by providing a partition wall 528 made of an insulating material between each EL layer and light-receiving layer as shown in this configuration example, it is possible to suppress the occurrence of crosstalk between adjacent devices.

[0265] Furthermore, in the manufacturing method described in this embodiment, the side surfaces (or edges) of the EL layer and the light-receiving layer are exposed during the patterning process. Therefore, the EL layer and the light-receiving layer are likely to deteriorate due to the intrusion of oxygen, water, and the like from the side surfaces (or edges) of the EL layer and the light-receiving layer. Therefore, by providing the partition 528, it is possible to suppress the deterioration of the EL layer and the light-receiving layer during the manufacturing process.

[0266] Furthermore, providing the partition 528 can also flatten recesses formed between adjacent devices. Flattening the recesses can prevent disconnection of the electrodes 552 formed on each EL layer and light-receiving layer. Examples of insulating materials used to form the partition 528 include organic materials such as acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenolic resin, and precursors of these resins. Organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, and alcohol-soluble polyamide resin may also be used. Photosensitive resins such as photoresists can also be used. The photosensitive resin can be a positive-type material or a negative-type material.

[0267] By using a photosensitive resin, the partition wall 528 can be formed only by exposure and development processes. Alternatively, the partition wall 528 may be formed using a negative photosensitive resin (e.g., a resist material). When an insulating layer containing an organic material is used for the partition wall 528, it is preferable to use a material that absorbs visible light. Using a material that absorbs visible light for the partition wall 528 allows the partition wall 528 to absorb light emitted from the EL layer, thereby suppressing light (stray light) that may leak into the adjacent EL layer and light-receiving layer. Therefore, a display panel with high display quality can be provided.

[0268] The difference in height between the upper surface of the partition wall 528 and the upper surface of any one of the EL layer 103B, the EL layer 103G, the EL layer 103R, and the light-receiving layer 103PS is, for example, preferably 0.5 times or less, more preferably 0.3 times or less, the thickness of the partition wall 528. For example, the partition wall 528 may be provided so that the upper surface of any one of the EL layer 103B, the EL layer 103G, the EL layer 103R, and the light-receiving layer 103PS is higher than the upper surface of the partition wall 528. For example, the partition wall 528 may be provided so that the upper surface of the partition wall 528 is higher than the upper surfaces of the EL layer 103B, the EL layer 103G, the EL layer 103R, and the light-receiving layer 103PS.

[0269] In a high-resolution light-receiving and light-emitting device (display panel) having a resolution of more than 1000 ppi, if electrical conduction is found between the EL layer 103B, the EL layer 103G, the EL layer 103R, and the light-receiving layer 103PS, crosstalk occurs, narrowing the color gamut that can be displayed by the light-receiving and light-emitting device. By providing the partition 528 in a high-resolution display panel having a resolution of more than 1000 ppi, preferably a high-resolution display panel having a resolution of more than 2000 ppi, and more preferably an ultra-high-resolution display panel having a resolution of more than 5000 ppi, a display panel that can display vivid colors can be provided.

[0270] 2B and 2C are schematic top views of the light emitting and receiving device 700 corresponding to the dashed line Ya-Yb in the cross-sectional view of FIG. 2A. That is, the light emitting devices 550B, 550G, and 550R are arranged in a matrix. FIG. 2B shows a so-called stripe arrangement in which light emitting devices of the same color are arranged in the X direction. FIG. 2C shows a configuration in which light emitting devices of the same color are arranged in the X direction, but with a pattern formed for each pixel. The arrangement of the light emitting devices is not limited to this; other arrangements, such as a delta arrangement or a zigzag arrangement, may also be used, and a pentile arrangement or a diamond arrangement may also be used.

[0271] Since photolithography is used to form patterns in the separation process of each EL layer (103B, 103G, 103R) and the light-receiving layer 103PS, a high-resolution light-receiving and light-emitting device (display panel) can be fabricated. Furthermore, the edges (side surfaces) of each EL layer processed by patterning using photolithography have a shape that is approximately flush with the surface (or located on approximately the same plane). Furthermore, the edges (side surfaces) of each light-receiving layer processed by patterning using photolithography have a shape that is approximately flush with the surface (or located on approximately the same plane). Furthermore, the width (SE) of the gap 580 between each EL layer and the light-receiving layer is preferably 5 μm or less, more preferably 1 μm or less. The width of the gap between the EL layer and the light-receiving element is preferably greater than the width of the gap between the EL layers.

[0272] In the EL layer, the hole injection layer included in the hole transport region located between the anode and the light-emitting layer often has high conductivity, and therefore, if it is formed as a layer common to adjacent light-emitting devices, it may cause crosstalk. Therefore, by separating the EL layer by pattern formation using photolithography as shown in this configuration example, it is possible to suppress the occurrence of crosstalk between adjacent light-emitting devices.

[0273] 2B and 2C. Fig. 2D shows a connection portion 130 where the connection electrode 551C and the electrode 552 are electrically connected. In the connection portion 130, the electrode 552 is provided in contact with the connection electrode 551C. A partition wall 528 is provided to cover the end of the connection electrode 551C.

[0274] 3A, an electrode 551B, an electrode 551G, an electrode 551R, and an electrode 551PS are formed. For example, a conductive film is formed on the functional layer 520 formed on the first substrate 510, and processed into a predetermined shape by photolithography.

[0275] The conductive film can be formed by sputtering, chemical vapor deposition (CVD), molecular beam epitaxy (MBE), vacuum evaporation, pulsed laser deposition (PLD), atomic layer deposition (ALD), or the like. CVD methods include plasma enhanced chemical vapor deposition (PECVD) and thermal CVD. One type of thermal CVD method is metal organic chemical vapor deposition (MOCVD).

[0276] In addition to the photolithography method described above, the conductive film may be processed by a nanoimprint method, a sandblasting method, a lift-off method, etc. Alternatively, an island-shaped thin film may be directly formed by a film formation method using a shielding mask such as a metal mask.

[0277] There are two typical photolithography methods. One is a method in which a resist mask is formed on a thin film to be processed, the thin film is processed by etching or the like, and the resist mask is then removed. The other is a method in which a photosensitive thin film is formed, and then the thin film is processed into a desired shape by exposure and development. Note that the former method includes heat treatment steps such as pre-applied bake (PAB) after resist application and post-exposure bake (PEB) after exposure. In one embodiment of the present invention, lithography is used not only for processing a conductive film but also for processing a thin film (a film made of an organic compound or a film partially containing an organic compound) used to form an EL layer.

[0278] In photolithography, the light used for exposure can be, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or a mixture of these. Other light sources that can be used include ultraviolet light, KrF laser light, ArF laser light, etc. Exposure can also be performed by immersion exposure technology. Extreme ultraviolet (EUV) light or X-rays can also be used as the light used for exposure. An electron beam can also be used instead of light used for exposure. Extreme ultraviolet light, X-rays, or an electron beam are preferred because they enable extremely fine processing. When exposure is performed by scanning a beam such as an electron beam, a photomask is not required.

[0279] For etching the thin film using a resist mask, dry etching, wet etching, sandblasting, or the like can be used.

[0280] 3B , a hole injection / transport layer 104B, a light-emitting layer 105B, and an electron transport layer 108B are formed on the electrode 551B, the electrode 551G, the electrode 551R, and the electrode 551PS. The hole injection / transport layer 104B, the light-emitting layer 105B, and the electron transport layer 108B can be formed by, for example, vacuum evaporation. Furthermore, a sacrificial layer 110B is formed on the electron transport layer 108B. The materials described in Embodiment 2 can be used to form the hole injection / transport layer 104B, the light-emitting layer 105B, and the electron transport layer 108B.

[0281] The sacrificial layer 110B is preferably a film that is highly resistant to the etching processes of the hole injection / transport layer 104B, the light-emitting layer 105B, and the electron transport layer 108B, i.e., a film with a large etching selectivity. The sacrificial layer 110B preferably has a stacked structure of a first sacrificial layer and a second sacrificial layer that have different etching selectivity. The sacrificial layer 110B can be a film that can be removed by wet etching, which causes minimal damage to the EL layer 103B. Oxalic acid or the like can be used as an etching material for wet etching.

[0282] The sacrificial layer 110B may be, for example, a metal film, an alloy film, a metal oxide film, a semiconductor film, an inorganic insulating film, etc. The sacrificial layer 110B may be formed by various film formation methods such as a sputtering method, a vapor deposition method, a CVD method, an ALD method, etc.

[0283] The sacrificial layer 110B may be made of 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 such a metal material. In particular, it is preferable to use a low-melting-point material such as aluminum or silver.

[0284] The sacrificial layer 110B may be made of a metal oxide such as indium gallium zinc oxide (In-Ga-Zn oxide, also referred to as IGZO). Other examples include indium oxide, indium zinc oxide (In-Zn oxide), indium tin 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), and indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide). Alternatively, silicon-containing indium tin oxide may be used.

[0285] The present invention can also be applied to a case where, instead of the gallium, an element M (wherein 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) is used. In particular, it is preferable that M is one or more elements selected from gallium, aluminum, and yttrium.

[0286] The sacrificial layer 110B may be made of an inorganic insulating material such as aluminum oxide, hafnium oxide, or silicon oxide.

[0287] Furthermore, the sacrificial layer 110B is preferably made of a material that can be dissolved in a chemically stable solvent, as compared with the electron transport layer 108B located at the top. Materials that dissolve in water or alcohol are particularly suitable for use in the sacrificial layer 110B. When forming the sacrificial layer 110B, it is preferable to apply the sacrificial layer 110B dissolved in a solvent such as water or alcohol using a wet film formation method, and then perform a heat treatment to evaporate the solvent. In this case, performing the heat treatment under a reduced pressure atmosphere is preferable because it allows the solvent to be removed at a low temperature and in a short time, thereby reducing thermal damage to the hole injection / transport layer 104B, the light-emitting layer 105B, and the electron transport layer 108B.

[0288] When the sacrificial layer 110B has a laminated structure, a layer made of the above-mentioned material can be used as a first sacrificial layer, and a second sacrificial layer can be formed thereon to form a laminated structure.

[0289] In this case, the second sacrificial layer is a film used as a hard mask when etching the first sacrificial layer. Furthermore, the first sacrificial layer is exposed when the second sacrificial layer is processed. Therefore, a combination of films with a high etching selectivity is selected for the first sacrificial layer and the second sacrificial layer. Therefore, a film that can be used for the second sacrificial layer can be selected depending on the etching conditions for the first sacrificial layer and the second sacrificial layer.

[0290] For example, when dry etching using a gas containing fluorine (also called a fluorine-based gas) is used to etch the second sacrificial layer, silicon, silicon nitride, silicon oxide, tungsten, titanium, molybdenum, tantalum, tantalum nitride, an alloy containing molybdenum and niobium, an alloy containing molybdenum and tungsten, etc. can be used for the second sacrificial layer. Here, metal oxide films such as IGZO and ITO can be used as films that can have a large etching selectivity (i.e., can slow the etching rate) compared to dry etching using the fluorine-based gas, and these can be used for the first sacrificial layer.

[0291] However, the second sacrificial layer is not limited to this, and can be selected from various materials depending on the etching conditions of the first sacrificial layer and the second sacrificial layer, for example, from among the films that can be used for the first sacrificial layer.

[0292] The second sacrificial layer may be, for example, a nitride film, such as silicon nitride, aluminum nitride, hafnium nitride, titanium nitride, tantalum nitride, tungsten nitride, gallium nitride, or germanium nitride.

[0293] Alternatively, an oxide film can be used as the second sacrificial layer. Typically, an oxide film or an oxynitride film such as silicon oxide, silicon oxynitride, aluminum oxide, aluminum oxynitride, hafnium oxide, or hafnium oxynitride can be used.

[0294] Next, as shown in FIG. 3C , resist is applied to the sacrificial layer 110B, and the resist is formed into a desired shape (resist mask: REG) using photolithography. When performing this method, heat treatment processes such as pre-applied bake (PAB) after resist application and post-exposure bake (PEB) after exposure are also performed. For example, the PAB temperature is approximately 100° C., and the PEB temperature is approximately 120° C. Therefore, the light-emitting device must be able to withstand these processing temperatures.

[0295] Next, using the obtained resist mask REG, a portion of the sacrificial layer 110B that is not covered by the resist mask REG is removed by etching. After the resist mask REG is removed, a portion of the hole injection / transport layer 104B, the light-emitting layer 105B, and the electron transport layer 108B that is not covered by the sacrificial layer 110B is removed by etching, and the hole injection / transport layer 104B, the light-emitting layer 105B, and the electron transport layer 108B are processed into a shape that has a side surface on the electrode 551B (or has an exposed side surface) or into a strip-like shape extending in a direction intersecting with the plane of the page. Dry etching is preferred for this etching. When the sacrificial layer 110B has a laminated structure of the first and second sacrificial layers, a portion of the second sacrificial layer may be etched using the resist mask REG, and then the resist mask REG may be removed. Then, a portion of the first sacrificial layer may be etched using the second sacrificial layer as a mask, thereby processing the hole injection / transport layer 104B, the light-emitting layer 105B, and the electron transport layer 108B into the predetermined shapes. These etching processes result in the shape shown in FIG. 4A .

[0296] 4B , a hole injection / transport layer 104G, a light-emitting layer 105G, and an electron transport layer 108G are formed on the sacrificial layer 110B, the electrode 551G, the electrode 551R, and the electrode 551PS. The materials used to form the hole injection / transport layer 104G, the light-emitting layer 105G, and the electron transport layer 108G can be the same as those described in Embodiment 2. The hole injection / transport layer 104G, the light-emitting layer 105G, and the electron transport layer 108G can be formed by vacuum evaporation, for example.

[0297] 4C , a sacrificial layer 110G is formed on the electron transport layer 108G, a resist is applied to the sacrificial layer 110G, and the resist is formed into a desired shape (resist mask: REG) using photolithography. The portion of the sacrificial layer 110G that is not covered by the resulting resist mask REG is then removed by etching. After the resist mask REG is removed, the portions of the hole injection / transport layer 104G, the light-emitting layer 105G, and the electron transport layer 108G that are not covered by the sacrificial layer 110G are then removed by etching. The hole injection / transport layer 104G, the light-emitting layer 105G, and the electron transport layer 108G are then shaped to have a side surface on the electrode 551G (or have an exposed side surface) or a strip-like shape extending in a direction intersecting the plane of the page. Dry etching is preferred for this etching. The sacrificial layer 110G can be made of the same material as the sacrificial layer 110B. When the sacrificial layer 110G has a laminated structure of the first and second sacrificial layers, the second sacrificial layer may be partially etched using a resist mask REG, and then the resist mask REG may be removed. Then, the first sacrificial layer may be partially etched using the second sacrificial layer as a mask, thereby processing the hole injection / transport layer 104G, the light-emitting layer 105G, and the electron transport layer 108G into the predetermined shapes. These etching processes result in the shape shown in FIG. 5A .

[0298] 5B , a hole injection / transport layer 104R, a light-emitting layer 105R, and an electron transport layer 108R are formed on the sacrificial layer 110B, the sacrificial layer 110G, the electrode 551R, and the electrode 551PS. The materials used to form the hole injection / transport layer 104R, the light-emitting layer 105R, and the electron transport layer 108R can be the same as those described in Embodiment 2. The hole injection / transport layer 104R, the light-emitting layer 105R, and the electron transport layer 108R can be formed by vacuum deposition, for example.

[0299] 5C , a sacrificial layer 110R is formed on the electron transport layer 108R, a resist is applied to the sacrificial layer 110R, and the resist is formed into a desired shape (resist mask: REG) using photolithography. The portion of the sacrificial layer 110R that is not covered by the resulting resist mask REG is then removed by etching. After the resist mask REG is removed, the portions of the hole injection / transport layer 104R, the light-emitting layer 105R, and the electron transport layer 108R that are not covered by the sacrificial layer 110R are then removed by etching, thereby processing the hole injection / transport layer 104R, the light-emitting layer 105R, and the electron transport layer 108R into a shape that has a side surface on the electrode 551R (or has an exposed side surface) or into a strip-like shape extending in a direction intersecting the plane of the page. Dry etching is preferred for this etching. The sacrificial layer 110R can be made of the same material as the sacrificial layer 110B. When the sacrificial layer 110R has a laminated structure of the first and second sacrificial layers, the second sacrificial layer may be partially etched using a resist mask REG, and then the resist mask REG may be removed. Then, the first sacrificial layer may be partially etched using the second sacrificial layer as a mask, thereby processing the hole injection / transport layer 104R, the light-emitting layer 105R, and the electron transport layer 108R into the predetermined shapes. These etching processes result in the shape shown in FIG. 6A .

[0300] Next, as shown in FIG. 6B , a first transport layer 104PS, an active layer 105PS, and a second transport layer 108PS are formed on the sacrificial layer 110B, the sacrificial layer 110G, the sacrificial layer 110R, and the electrode 551PS. In forming the first transport layer 104PS, the materials shown for the hole injection layer and the hole transport layer in Embodiment 2 can be used, for example. In addition, in forming the active layer 105PS, the materials shown for the electron transport layer and the electron injection layer in Embodiment 8 can be used, for example. In addition, in forming the second transport layer 108PS, the materials shown for the electron transport layer and the electron injection layer in Embodiment 2 can be used, for example. The first transport layer 104PS, the active layer 105PS, and the second transport layer 108PS can be formed by, for example, vacuum deposition.

[0301] 6C , a sacrificial layer 110PS is formed on the second transport layer 108PS, a resist is applied to the sacrificial layer 110PS, and the resist is formed into a desired shape (resist mask: REG) using photolithography. The portion of the sacrificial layer 110PS that is not covered by the resulting resist mask REG is removed by etching. After the resist mask REG is removed, the portions of the first transport layer 104PS, the active layer 105PS, and the second transport layer 108PS that are not covered by the sacrificial layer 110PS are removed by etching. This allows the first transport layer 104PS, the active layer 105PS, and the second transport layer 108PS to be shaped so as to have a side surface on the electrode 551PS (or have an exposed side surface) or to have a strip-like shape extending in a direction intersecting the plane of the page. Dry etching is preferred for this etching. Furthermore, the sacrificial layer 110PS can be made of the same material as the sacrificial layer 110B. When the sacrificial layer 110PS has a laminated structure of the first and second sacrificial layers, a portion of the second sacrificial layer may be etched using a resist mask REG, and then the resist mask REG may be removed. Then, a portion of the first sacrificial layer may be etched using the second sacrificial layer as a mask, thereby processing the first transport layer 104PS, the active layer 105PS, and the second transport layer 108PS into the predetermined shapes. These etching processes result in the shape shown in FIG. 6D .

[0302] Next, as shown in FIG. 7A, an insulating layer 107 is formed on the sacrificial layers 110B, 110G, 110R, and 110PS.

[0303] The insulating layer 107 can be formed by, for example, ALD. In this case, as shown in FIG. 7A , the insulating layer 107 is formed in contact with the side surfaces (ends) of the hole injection / transport layers (104B, 104G, 104R), light-emitting layers (105B, 105G, 105R), and electron transport layers (108B, 108G, 108R) of the light-emitting devices, as well as the first transport layer 104PS, active layer 105PS, and second transport layer 108PS of the light-receiving device. This prevents oxygen, moisture, or their constituent elements from penetrating into the interior from the side surfaces. Examples of materials that can be used for the insulating layer 107 include aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indium gallium zinc oxide, silicon nitride, and silicon nitride oxide.

[0304] Next, as shown in FIG. 7B , after removing a portion of the insulating layer 107 and the sacrificial layers (110B, 110G, 110R, 110PS), an electron injection layer 109 is formed on the insulating layer 107, the electron transport layers (108B, 108G, 108R), and the second transport layer 108PS. The materials described in Embodiment 2 can be used to form the electron injection layer 109. The electron injection layer 109 is formed, for example, by vacuum deposition. The electron injection layer 109 is in contact with the hole injection / transport layers (104B, 104G, 104R), the light-emitting layers (105B, 105G, 105R), and the electron transport layers (108B, 108G, 108R) of the light-emitting devices, as well as the first transport layer 104PS, the active layer 105PS, and the second transport layer 108PS of the light-receiving device, at their respective side surfaces (ends) via the insulating layer 107.

[0305] Next, as shown in FIG. 7C , an electrode 552 is formed. The electrode 552 is formed by, for example, vacuum deposition. The electrode 552 is formed on the electron injection layer 109. The electrode 552 is structured to be in contact with the hole injection / transport layers (104B, 104G, 104R), light-emitting layers (105B, 105G, 105R), and electron transport layers (108B, 108G, 108R) of the light-emitting devices, and with the side surfaces (ends) of the first transport layer 104PS, active layer 105PS, and second transport layer 108PS of the light-receiving device, via the electron injection layer 109 and the insulating layer 107. This makes it possible to prevent electrical short-circuiting between the hole injection / transport layers (104B, 104G, 104R), light-emitting layers (105B, 105G, 105R), and electron transport layers (108B, 108G, 108R) of each light-emitting device, and between the first transport layer 104PS, active layer 105PS, and second transport layer 108PS of the light-receiving device and the electrode 552.

[0306] Through the above steps, EL layers 103B, 103G, 103R, and light-receiving layer 103PS in light-emitting devices 550B, 550G, and 550R, and light-receiving device 550PS can be separated and processed, respectively.

[0307] In addition, since pattern formation is performed by photolithography in the separation processing of these EL layers (103B, 103G, 103R) and the light receiving layer 103PS, a high-definition light receiving and emitting device (display panel) can be manufactured. Furthermore, the ends (side surfaces) of each layer of the EL layer processed by pattern formation by photolithography have a shape that has approximately the same surface (or is located on approximately the same plane). Furthermore, the side surfaces (end surfaces) of each layer of the light receiving layer processed by pattern formation by photolithography have a shape that has approximately the same surface (or is located on approximately the same plane).

[0308] Furthermore, the hole injection / transport layers (104B, 104G, 104R) in the EL layer and the first transport layer 104PS in the light-receiving layer often have high electrical conductivity, which can cause crosstalk if they are formed as a layer common to adjacent devices. Therefore, by separating each layer through pattern formation by photolithography, as shown in this configuration example, it is possible to suppress the occurrence of crosstalk between adjacent devices.

[0309] In addition, the hole injection / transport layers (104B, 104G, 104R), light-emitting layers (105B, 105G, 105R), and electron transport layers (108B, 108G, 108R) included in each EL layer (103B, 103G, 103R) of each light-emitting device in this configuration, and the first transport layer 104PS, active layer 105PS, and second transport layer 108PS included in the absorption layer 103PS of the light-receiving device are patterned by photolithography during separation processing, so that the edges (side surfaces) of each processed EL layer have shapes that are approximately flush with each other (or located on approximately the same plane). Furthermore, the edges (side surfaces) of each layer of the absorption layer processed by patterning by photolithography have shapes that are approximately flush with each other (or located on approximately the same plane).

[0310] Furthermore, the hole injection / transport layers (104B, 104G, 104R), light-emitting layers (105B, 105G, 105R), and electron transport layers (108B, 108G, 108R) included in each EL layer (103B, 103G, 103R) of each light-emitting device, and the first transport layer 104PS, active layer 105PS, and second transport layer 108PS included in the light-receiving layer 103PS of the light-receiving device are patterned by photolithography during separation processing, so that each processed end (side) has a gap 580 between adjacent devices. Note that in Figure 7C, when the gap 580 is represented by SE, the smaller the distance SE, the higher the aperture ratio and the higher the definition. On the other hand, the larger the distance SE, the more tolerant the influence of manufacturing process variations between adjacent devices can be, and therefore the manufacturing yield can be increased. Because the light-emitting devices and light-receiving devices manufactured according to this specification are suitable for miniaturization processes, the distance SE between the EL layers or light-receiving layers of adjacent devices can be set to 0.5 μm or more and 5 μm or less, preferably 1 μm or more and 3 μm or less, more preferably 1 μm or more and 2.5 μm or less, and even more preferably 1 μm or more and 2 μm or less. Typically, the distance SE is preferably 1 μm or more and 2 μm or less (e.g., 1.5 μm or thereabouts).

[0311] In this specification and the like, a device fabricated using a metal mask or an FMM (fine metal mask, high-resolution metal mask) may be referred to as a device with an MM (metal mask) structure. In addition, in this specification and the like, a device fabricated without using a metal mask or an FMM may be referred to as a device with an MML (metal maskless) structure. Because an MML structure light-emitting and receiving device is fabricated without using a metal mask, it has a higher degree of design freedom in terms of pixel arrangement, pixel shape, and the like than an FMM structure light-emitting and receiving device or an MM structure.

[0312] The island-shaped EL layer in the MML-structure light-emitting / receiving device is not formed by a metal mask pattern, but is formed by processing the EL layer after it has been formed. This makes it possible to realize a light-emitting / receiving device with higher resolution or a higher aperture ratio than ever before. Furthermore, since the EL layer can be made separately for each color, a light-emitting / receiving device with extremely vivid, high-contrast, and high display quality can be realized. Furthermore, providing a sacrificial layer on the EL layer reduces damage to the EL layer during the manufacturing process, thereby improving the reliability of the light-emitting device.

[0313] Furthermore, the compound having an azine skeleton according to one embodiment of the present invention (also referred to as the present compound) described in Embodiment 1 and the like has features such as high heat resistance. Therefore, by using the compound in an electron transport injection layer, an electron transport layer, a light-emitting layer, a hole-transport layer, a hole injection layer, an intermediate layer, or a capping layer, the effect of reducing damage during the manufacturing process of an MML structure can be enhanced. In particular, by using the compound in an upper layer, such as a capping layer, an electron injection layer, or an electron transport layer, damage to lower layers can be reduced. For example, when the compound of the present invention is used in an electron-transport layer, it is preferable to use a compound having a higher Tg than the host material of the light-emitting layer. Similarly, when the compound of the present invention is used in an electron-transport layer, it is preferable to use a compound having a higher Tg than the material of the hole-transport layer. As the compound having an azine skeleton, the compounds represented by General Formulas (G1) to (G4) described in Embodiment 1 are preferably used, but the present invention is not limited thereto.

[0314] Furthermore, when the compound of the present application is used as a common layer such as the electron injection layer 109, it is preferable that the electron injection layer 109 and the partition wall 528 are disposed so as to overlap. The high Tg of the compound of the present application can reduce damage to the partition wall 528. A transport layer (electron transport layer 108B, electron transport layer 108G, electron transport layer 108R, or second transport layer 108PS) may be formed on the partition wall 528. In this case, it is preferable to use the compound of the present application as the transport layer and dispose the transport layer and the partition wall so as to overlap. It is also effective to dispose a layer containing the compound of the present application on the partition wall between the light-receiving device 550PS and the light-emitting device so as to overlap. The electron transport layer 108B, electron transport layer 108G, electron transport layer 108R, and second transport layer 108PS may be provided continuously rather than as separate layers.

[0315] Furthermore, in a bendable device (also referred to as a flexible device) using a flexible substrate as a substrate, it is effective to employ a compound of the present application having high resistance (heat resistance, stability, etc.). For example, it is effective to provide a layer containing the compound of the present application overlapping a bending portion that is prone to load. The compound of the present application may also be overlappingly disposed between the partition wall 528 and the bending portion. Furthermore, in a device having multiple bending portions or a winding-type device, since there are many portions to which load is applied, it is preferable to provide a partition wall 528 and a layer containing the compound of the present application overlapping at such portions. It is also preferable to overlap a cap layer, a layer containing the compound of the present application, and a partition wall at the bending portion.

[0316] In the light-emitting devices 550B, 550G, and 550R shown in Figures 2A and 7C, the width of the EL layers (103B, 103G, and 103R) is approximately equal to the width of the electrodes (551B, 551G, and 551R), and in the light-receiving device 550PS, the width of the light-receiving layer 103PS is approximately equal to the width of the electrode 551PS, but one embodiment of the present invention is not limited to this.

[0317] In the light-emitting devices 550B, 550G, and 550R, the width of the EL layers (103B, 103G, and 103R) may be smaller than the width of the electrodes (551B, 551G, and 551R). In the light-receiving device 550PS, the width of the light-receiving layer 103PS may be smaller than the width of the electrode 551PS. Figure 7D shows an example in which the width of the EL layers (103B and 103G) in the light-emitting devices 550B and 550G is smaller than the width of the electrodes (551B and 551G).

[0318] In light-emitting devices 550B, 550G, and 550R, the width of the EL layers (103B, 103G, and 103R) may be larger than the width of the electrodes (551B, 551G, and 551R). In light-receiving device 550PS, the width of light-receiving layer 103PS may be larger than the width of electrode 551PS. Figure 7E shows an example in which the width of EL layer 103R is larger than the width of electrode 551R in light-emitting device 550R.

[0319] The structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiments.

[0320] (Embodiment 4) In this embodiment, a device 720 will be described with reference to FIGS. 8 to 10. Note that the device 720 shown in FIGS. 8 to 10 is a light-emitting device because it includes the light-emitting device described in Embodiment 2. However, the device 720 described in this embodiment can also be called a display panel or a display device because it can be applied to a display portion of an electronic device or the like. Furthermore, when the device uses the light-emitting device as a light source and includes a light-receiving device that can receive light from the light-emitting device, it can also be called a light-receiving / emitting device. Note that these light-emitting devices, display panels, display devices, and light-receiving / emitting devices have at least a light-emitting device.

[0321] Furthermore, the light-emitting device, display panel, display device, and light-emitting and receiving device of the present embodiment can be a high-resolution or large-sized light-emitting device, display panel, display device, and light-emitting and receiving device. Therefore, the light-emitting device, display panel, display device, and light-emitting and receiving device of the present embodiment can be used in the display portion of electronic devices having relatively large screens, such as television devices, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, smartphones, wristwatch-type terminals, tablet terminals, personal digital assistants, and sound reproducing devices.

[0322] FIG. 8A shows a top view of these devices (including a light-emitting device, a display panel, a display device, and a light-emitting and receiving device) 720 .

[0323] 8A , the device 720 has a configuration in which a substrate 710 and a substrate 711 are bonded together. The device 720 also has a display region 701, a circuit 704, wiring 706, and the like. The display region 701 has a plurality of pixels, and a pixel 703(i, j) shown in FIG. 8A has a pixel 703(i+1, j) adjacent to the pixel 703(i, j) as shown in FIG. 8B .

[0324] 8A , the device 720 includes an IC (integrated circuit) 712 provided on a substrate 710 by a chip-on-glass (COG) method, a chip-on-film (COF) method, or the like. For example, an IC having a scanning line driver circuit or a signal line driver circuit can be used as the IC 712. In FIG. 8A , an IC having a signal line driver circuit is used as the IC 712, and a scanning line driver circuit is used as the circuit 704.

[0325] The wiring 706 has a function of supplying signals and power to the display region 701 and the circuit 704. The signals and power are input to the wiring 706 from the outside through a flexible printed circuit (FPC) 713 or are input to the wiring 706 from an IC 712. Note that the device 720 may not include an IC. Alternatively, the IC may be mounted on the FPC by a COF method or the like.

[0326] FIG. 8B shows pixel 703(i,j) and pixel 703(i+1,j) in the display region 701. That is, pixel 703(i,j) can be configured to have multiple types of subpixels having light-emitting devices that emit different colors. Alternatively, in addition to the above, pixel 703(i,j) can be configured to include multiple subpixels having light-emitting devices that emit the same color. When a pixel has multiple types of subpixels having light-emitting devices that emit different colors, the pixel can be configured to have three types of subpixels. Examples of the three subpixels include subpixels of three colors: red (R), green (G), and blue (B), or subpixels of three colors: yellow (Y), cyan (C), and magenta (M). Alternatively, the pixel can be configured to have four types of subpixels. Examples of the four subpixels include subpixels of four colors: R, G, B, and white (W), or subpixels of four colors: R, G, B, and Y. Specifically, the pixel 703(i,j) can be configured with a sub-pixel 702B(i,j) that displays blue, a sub-pixel 702G(i,j) that displays green, and a sub-pixel 702R(i,j) that displays red.

[0327] Additionally, device 720 includes subpixels with light-receiving devices as well as subpixels with light-emitting devices.

[0328] Pixels 703(i,j) shown in Figures 8C to 8E show examples of various layouts including subpixels 702PS(i,j) having light-receiving devices. Note that the pixel arrangement shown in Figure 8C is a stripe arrangement, and the pixel arrangement shown in Figure 8D is a matrix arrangement. Furthermore, the pixel arrangement shown in Figure 8E has a configuration in which three subpixels (subpixels R, G, and PS) are vertically arranged next to one subpixel (subpixel B).

[0329] 8F , a subpixel 702IR(i,j) that emits infrared light may be added to the above set to form pixel 703(i,j). The pixel arrangement shown in FIG. 8F has a configuration in which three vertically elongated subpixels G, B, and R are arranged horizontally, and below them, a subpixel PS and a horizontally elongated subpixel IR are arranged horizontally. Specifically, a subpixel 702IR(i,j) that emits light containing light having a wavelength of 650 nm or more and 1000 nm or less may be used for pixel 703(i,j). Although the wavelength of light detected by the subpixel 702PS(i,j) is not particularly limited, it is preferable that the light receiving device of the subpixel 702PS(i,j) is sensitive to light emitted by the light emitting device of the subpixel 702R(i,j), the subpixel 702G(i,j), the subpixel 702B(i,j), or the subpixel 702IR(i,j). For example, it is preferable to detect one or more of light in wavelength ranges such as blue, purple, blue-purple, green, yellow-green, yellow, orange, and red, and light in the infrared wavelength range.

[0330] 8B to 8F, various arrangements of the sub-pixels can be applied, such as a stripe arrangement, an S-stripe arrangement, a matrix arrangement, a delta arrangement, a Bayer arrangement, and a pentile arrangement.

[0331] Examples of the top surface shape of the sub-pixel include a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon, a polygon with rounded corners, an ellipse, a circle, etc. The top surface shape of the sub-pixel here corresponds to the top surface shape of the light-emitting region of the light-emitting device.

[0332] Furthermore, when a pixel has not only a light-emitting device but also a light-receiving device, the pixel has a light-receiving function, so that it is possible to detect contact or proximity of an object while displaying an image. For example, instead of displaying an image using all of the sub-pixels of the light-emitting device, some of the sub-pixels can emit light as a light source and the remaining sub-pixels can display an image.

[0333] It is preferable that the light-receiving area of ​​the subpixel 702PS(i,j) be smaller than the light-emitting area of ​​the other subpixels. The smaller the light-receiving area, the narrower the imaging range, which makes it possible to suppress blurring in the imaging result and improve resolution. Therefore, by using the subpixel 702PS(i,j), high-definition or high-resolution imaging can be performed. For example, the subpixel 702PS(i,j) can be used to capture images for personal authentication using fingerprints, palm prints, irises, pulse shapes (including vein shapes and arterial shapes), faces, etc.

[0334] The subpixel 702PS(i,j) can be used as a touch sensor (also called a direct touch sensor) or a near-touch sensor (also called a hover sensor, hover touch sensor, non-contact sensor, or touchless sensor). For example, the subpixel 702PS(i,j) preferably detects infrared light. This enables touch detection even in dark places.

[0335] Here, a touch sensor or near-touch sensor can detect the proximity or contact of an object (such as a finger, hand, or pen). A touch sensor can detect an object by direct contact between the light-emitting and receiving device and the object. A near-touch sensor can detect an object even if the object does not come into contact with the light-emitting and receiving device. For example, a configuration in which the light-emitting and receiving device can detect an object when the distance between the light-emitting and receiving device and the object is between 0.1 mm and 300 mm, preferably between 3 mm and 50 mm, is preferable. This configuration enables operation without the object directly touching the light-emitting and receiving device, in other words, non-contact (touchless) operation of the light-emitting and receiving device. This configuration reduces the risk of the light-emitting and receiving device becoming dirty or scratched, or enables operation of the light-emitting and receiving device without the object directly touching dirt (e.g., dust, bacteria, or viruses) attached to the light-emitting and receiving device.

[0336] In order to capture high-resolution images, it is preferable that the sub-pixels 702PS(i,j) are provided in all pixels of the light-emitting and receiving device. On the other hand, when used in a touch sensor or near-touch sensor, the sub-pixels 702PS(i,j) do not require high accuracy compared to when capturing images of fingerprints, etc., so they may be provided in only some of the pixels of the light-emitting and receiving device. By making the number of sub-pixels 702PS(i,j) in the light-emitting and receiving device smaller than the number of sub-pixels 702R(i,j), etc., the detection speed can be increased.

[0337] Next, an example of a pixel circuit of a subpixel having a light-emitting device will be described with reference to FIG. 9A. The pixel circuit 530 shown in FIG. 9A includes a light-emitting device (EL) 550, a transistor M15, a transistor M16, a transistor M17, and a capacitor C3. A light-emitting diode can be used as the light-emitting device 550. In particular, it is preferable to use the light-emitting device described in Embodiment 2 as the light-emitting device 550.

[0338] 9A , the gate of the transistor M15 is electrically connected to a wiring VG, one of the source or drain is electrically connected to a wiring VS, and the other of the source or drain is electrically connected to one electrode of the capacitor C3 and the gate of the transistor M16. One of the source or drain of the transistor M16 is electrically connected to a wiring V4, and the other is electrically connected to the anode of the light-emitting device 550 and one of the source or drain of the transistor M17. The gate of the transistor M17 is electrically connected to a wiring MS, and the other of the source or drain is electrically connected to a wiring OUT2. The cathode of the light-emitting device 550 is electrically connected to a wiring V5.

[0339] A constant potential is supplied to the wiring V4 and the wiring V5. The anode side of the light-emitting device 550 can be set to a high potential, and the cathode side can be set to a lower potential than the anode side. The transistor M15 is controlled by a signal supplied to the wiring VG and functions as a selection transistor for controlling the selection state of the pixel circuit 530. The transistor M16 also functions as a drive transistor that controls the current flowing through the light-emitting device 550 depending on the potential supplied to its gate. When the transistor M15 is in a conductive state, the potential supplied to the wiring VS is supplied to the gate of the transistor M16, and the light emission brightness of the light-emitting device 550 can be controlled depending on the potential. The transistor M17 is controlled by a signal supplied to the wiring MS and has the function of outputting the potential between the transistor M16 and the light-emitting device 550 to the outside via the wiring OUT2.

[0340] Note that it is preferable to use transistors using a metal oxide (oxide semiconductor) in a semiconductor layer in which a channel is formed for the transistors M15, M16, and M17 included in the pixel circuit 530 of FIG. 9A and the transistors M11, M12, M13, and M14 included in the pixel circuit 530 of FIG. 9B.

[0341] A transistor using a metal oxide, which has a wider band gap and a lower carrier density than silicon, can achieve an extremely small off-state current. Therefore, the small off-state current allows charge stored in a capacitor connected in series with the transistor to be held for a long period of time. Therefore, it is preferable to use a transistor including an oxide semiconductor for the transistor M11, the transistor M12, and the transistor M15, which are connected in series with the capacitor C2 or the capacitor C3. Furthermore, by using a transistor including an oxide semiconductor for other transistors as well, manufacturing costs can be reduced.

[0342] Alternatively, the transistors M11 to M17 may be transistors in which silicon is used as a semiconductor in which a channel is formed. In particular, using silicon with high crystallinity, such as single crystal silicon or polycrystalline silicon, is preferable because high field-effect mobility can be achieved and higher-speed operation is possible.

[0343] Alternatively, a structure may be used in which at least one of the transistors M11 to M17 includes an oxide semiconductor and the remaining transistors include silicon.

[0344] Next, an example of a pixel circuit of a sub-pixel having a light receiving device will be described with reference to Fig. 9B. The pixel circuit 531 shown in Fig. 9B includes a light receiving device (PD) 560, transistors M11, M12, M13, and M14, and a capacitance element C2. In this example, a photodiode is used as the light receiving device (PD) 560.

[0345] 9B , the anode of the light-receiving device (PD) 560 is electrically connected to the wiring V1, and the cathode is electrically connected to one of the source and drain of the transistor M11. The gate of the transistor M11 is electrically connected to the wiring TX, and the other of the source and drain is electrically connected to one electrode of the capacitor C2, one of the source and drain of the transistor M12, and the gate of the transistor M13. The gate of the transistor M12 is electrically connected to the wiring RES, and the other of the source and drain is electrically connected to the wiring V2. The source and drain of the transistor M13 is electrically connected to the wiring V3, and the other of the source and drain is electrically connected to one of the source and drain of the transistor M14. The gate of the transistor M14 is electrically connected to the wiring SE1, and the other of the source and drain is electrically connected to the wiring OUT1.

[0346] A constant potential is supplied to the wiring V1, the wiring V2, and the wiring V3. When the light-receiving device (PD) 560 is driven with a reverse bias, a potential higher than the potential of the wiring V1 is supplied to the wiring V2. The transistor M12 is controlled by a signal supplied to the wiring RES and has a function of resetting the potential of a node connected to the gate of the transistor M13 to the potential supplied to the wiring V2. The transistor M11 is controlled by a signal supplied to the wiring TX and has a function of controlling the timing at which the potential of the node changes depending on the current flowing through the light-receiving device (PD) 560. The transistor M13 functions as an amplifying transistor that outputs according to the potential of the node. The transistor M14 is controlled by a signal supplied to the wiring SE1 and functions as a selection transistor for reading out an output according to the potential of the node to an external circuit connected to the wiring OUT1.

[0347] Note that although the transistors are shown as n-channel transistors in FIGS. 9A and 9B, p-channel transistors can also be used.

[0348] The transistors included in the pixel circuit 530 and the transistors included in the pixel circuit 531 are preferably formed side by side on the same substrate. In particular, it is preferable that the transistors included in the pixel circuit 530 and the transistors included in the pixel circuit 531 are mixed and periodically arranged in one region.

[0349] It is also preferable to provide one or more layers having one or both of a transistor and a capacitor element at a position overlapping the light receiving device (PD) 560 or the light emitting device (EL) 550. This can reduce the effective area occupied by each pixel circuit, thereby realizing a high-definition light receiving section or display section.

[0350] 9C shows an example of a specific structure of a transistor that can be applied to the pixel circuits described with reference to FIG. 9A and FIG. 9B. Note that a bottom-gate transistor, a top-gate transistor, or the like can be used as the transistor as appropriate.

[0351] 9C includes a semiconductor film 508, a conductive film 504, an insulating film 506, a conductive film 512A, and a conductive film 512B. The transistor is formed over, for example, an insulating film 501C. The transistor also includes an insulating film 516 (insulating films 516A and 516B) and an insulating film 518.

[0352] The semiconductor film 508 has a region 508A electrically connected to the conductive film 512A and a region 508B electrically connected to the conductive film 512B. The semiconductor film 508 has a region 508C between the region 508A and the region 508B.

[0353] The conductive film 504 has a region overlapping with the region 508C, and functions as a gate electrode.

[0354] The insulating film 506 has a region sandwiched between the semiconductor film 508 and the conductive film 504. The insulating film 506 functions as a first gate insulating film.

[0355] The conductive film 512A has a function as either a source electrode or a drain electrode, and the conductive film 512B has the other function as either a source electrode or a drain electrode.

[0356] The conductive film 524 can also be used for a transistor. The conductive film 524 has a region where the semiconductor film 508 is sandwiched between the conductive film 524 and the conductive film 504. The conductive film 524 functions as a second gate electrode. The insulating film 501D is sandwiched between the semiconductor film 508 and the conductive film 524 and functions as a second gate insulating film.

[0357] The insulating film 516 functions as, for example, a protective film that covers the semiconductor film 508. Specific examples of the insulating film 516 that can be used include a silicon oxide film, a silicon oxynitride film, a silicon nitride oxide film, a silicon nitride film, an aluminum oxide film, 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, and a neodymium oxide film.

[0358] The insulating film 518 is preferably formed using a material that has a function of suppressing diffusion of, for example, oxygen, hydrogen, water, an alkali metal, an alkaline earth metal, or the like. Specifically, for example, silicon nitride, silicon oxynitride, aluminum nitride, aluminum oxynitride, or the like can be used for the insulating film 518. Furthermore, the number of nitrogen atoms contained in silicon oxynitride and aluminum oxynitride is preferably larger than the number of oxygen atoms contained therein.

[0359] Note that a semiconductor film to be used for a transistor in a pixel circuit can be formed in the same process as a semiconductor film to be used for a transistor in a driver circuit. For example, a semiconductor film having the same composition as that of a semiconductor film to be used for a transistor in a pixel circuit can be used for the driver circuit.

[0360] The semiconductor film 508 preferably contains, for example, indium, M (M is one or more elements 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 elements selected from aluminum, gallium, yttrium, and tin.

[0361] In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also referred to as IGZO) for the semiconductor film 508. 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).

[0362] When the semiconductor film 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. The atomic ratio of metal elements in such an In-M-Zn oxide may be In:M:Zn=1:1:1 or a composition thereof in the vicinity thereof, In:M:Zn=1:1:1.2 or a composition thereof in the vicinity thereof, In:M:Zn=1:3:2 or a composition thereof in the vicinity thereof, In:M:Zn=1:3:4 or a composition thereof in the vicinity thereof, In:M:Zn=2:1:3 or a composition thereof in the vicinity thereof, In:M:Zn=3:1:2 or a composition thereof, or In:M:Zn=4:2:3. or a composition in the vicinity thereof, In:M:Zn = 4:2:4.1 or a composition in the vicinity thereof, In:M:Zn = 5:1:3 or a composition in the vicinity thereof, In:M:Zn = 5:1:6 or a composition in the vicinity thereof, In:M:Zn = 5:1:7 or a composition in the vicinity thereof, In:M:Zn = 5:1:8 or a composition in the vicinity thereof, In:M:Zn = 6:1:6 or a composition in the vicinity thereof, In:M:Zn = 5:2:5 or a composition in the vicinity thereof, etc. Note that a composition in the vicinity thereof includes a range of ±30% of the desired atomic ratio.

[0363] For example, when describing a composition having an atomic ratio of In:Ga:Zn=4:2:3 or thereabout, this 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. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn=5:1:6 or thereabout, this 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. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn=1:1:1 or thereabout, this 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.

[0364] 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 part) may be used. The use of a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0365] The semiconductor layer of the transistor preferably includes a metal oxide (also referred to as an oxide semiconductor). Examples of a crystalline oxide semiconductor include a c-axis-aligned crystalline (CAAC)-OS and a nanocrystalline (nc)-OS.

[0366] Alternatively, a transistor using silicon for a channel formation region (Si transistor) may be used. Examples of silicon include single crystal silicon (single crystal Si), polycrystalline silicon, and amorphous silicon. In particular, a transistor having low temperature polysilicon (LTPS) in a semiconductor layer (hereinafter also referred to as an LTPS transistor) may be used. An LTPS transistor has high field-effect mobility and favorable frequency characteristics.

[0367] By using Si transistors such as LTPS transistors, circuits that need to be driven at high frequencies (such as a source driver circuit) can be built on the same substrate as the display unit, which simplifies the external circuits mounted on the light-emitting device and reduces component and mounting costs.

[0368] An OS transistor has significantly higher field-effect mobility than a transistor using amorphous silicon. Furthermore, an OS transistor has significantly lower source-drain leakage current in an off state (hereinafter also referred to as off-state current), and can retain charge accumulated in a capacitor connected in series with the transistor for a long period of time. Furthermore, the use of an OS transistor can reduce the power consumption of a light-emitting device.

[0369] The off-state current of the OS transistor per 1 μm of channel width at room temperature is 1 aA (1×10 −１８ A) Below, 1zA (1×10 −２１ A) or less, or 1 yA (1 x 10 −２４ Note that the off-state current of a Si transistor per 1 μm of channel width at room temperature can be 1 fA (1×10 −１５ A) More than 1pA (1×10 −１２Therefore, it can be said that the off-state current of an OS transistor is about 10 orders of magnitude lower than that of a Si transistor.

[0370] Furthermore, 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 driving transistor included in the pixel circuit. Since an OS transistor has a higher source-drain withstand voltage than 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 driving 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.

[0371] Furthermore, when a transistor operates in the saturation region, an OS transistor can reduce the change in source-drain current with respect to a change in gate-source voltage compared to a Si transistor. Therefore, by using an OS transistor as a driving transistor included in a pixel circuit, the current flowing between the source and drain can be precisely controlled by changing the gate-source voltage, thereby controlling the amount of current flowing through the light-emitting device. This allows for a larger gradation in the pixel circuit.

[0372] Furthermore, in terms of saturation characteristics of the current that flows when a transistor operates in a saturation region, an OS transistor can pass a more stable current (saturation current) than a Si transistor, even when the source-drain voltage gradually increases. Therefore, by using an OS transistor as a driving transistor, 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 an OS transistor operates in a saturation region, the source-drain current of the OS transistor remains almost unchanged even when the source-drain voltage increases, thereby stabilizing the light-emitting luminance of the light-emitting device.

[0373] 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," "suppression of variations in light-emitting devices," and the like.

[0374] Alternatively, a semiconductor film used for a transistor in a driver circuit can be formed in the same process as a semiconductor film used for a transistor in a pixel circuit. Alternatively, the driver circuit can be formed over the same substrate as the substrate on which the pixel circuit is formed. Alternatively, the number of components constituting an electronic device can be reduced.

[0375] Silicon may also be used for the semiconductor film 508. Examples of silicon include single crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, a transistor having low temperature polysilicon (LTPS) in a semiconductor layer (hereinafter also referred to as an LTPS transistor) is preferably used. An LTPS transistor has high field-effect mobility and favorable frequency characteristics.

[0376] By using silicon transistors such as LTPS transistors, circuits that need to be driven at high frequencies (such as a source driver circuit) can be built on the same substrate as the display unit, which simplifies the external circuits mounted on the light-emitting device and reduces component and mounting costs.

[0377] At least one of the transistors included in the pixel circuit preferably includes a transistor (hereinafter also referred to as an OS transistor) having a metal oxide (hereinafter also referred to as an oxide semiconductor) as a semiconductor in which a channel is formed. The OS transistor has significantly higher field-effect mobility than a transistor using amorphous silicon. Furthermore, the OS transistor has significantly lower source-drain leakage current in an off state (hereinafter also referred to as an off-state current), and can retain charge accumulated in a capacitor connected in series with the transistor for a long period of time. Furthermore, the use of an OS transistor can reduce the power consumption of a light-emitting device.

[0378] By using LTPS transistors for some of the transistors included in a pixel circuit and OS transistors for the other transistors, a light-emitting device with low power consumption and high driving capability can be realized. As a more preferred example, it is preferable to use OS transistors as transistors that function as switches for controlling conduction / non-conduction between wirings, and LTPS transistors as transistors that control current. Note that a structure in which both LTPS transistors and OS transistors are combined is sometimes referred to as LTPO. By using LTPO, a display panel with low power consumption and high driving capability can be realized.

[0379] For example, one of the transistors provided in the pixel circuit 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 as the driving transistor. This allows the current flowing through the light-emitting device in the pixel circuit to be increased.

[0380] On the other hand, another transistor provided in the pixel circuit functions as a switch for controlling pixel selection / non-selection 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 as the selection transistor. This allows the gradation of a pixel to be maintained even when the frame frequency is significantly reduced (for example, 1 fps or less), and therefore power consumption can be reduced by stopping the driver when displaying a still image.

[0381] When an oxide semiconductor is used for the semiconductor film, the device 720 has a structure in which the oxide semiconductor is used for the semiconductor film and a light-emitting device with an MML (metal maskless) structure. This structure can significantly reduce leakage current that may flow through a transistor and leakage current that may flow between adjacent light-emitting devices (also referred to as lateral leakage current or side leakage current). Furthermore, with this structure, when an image is displayed on a display device, a viewer can observe one or more of image clarity, image sharpness, high saturation, and a high contrast ratio. Note that a structure in which leakage current that may flow through a transistor and lateral leakage current between light-emitting devices are extremely low can provide a display (also referred to as true black display) with extremely low light leakage (so-called floating black) that may occur during black display.

[0382] In particular, among light-emitting devices with an MML structure, by applying the SBS structure described above, the layers provided between the light-emitting devices (for example, organic layers used in common between the light-emitting devices, also called common layers) are configured to be separated, thereby making it possible to achieve a display with no side leakage or extremely little side leakage.

[0383] The configuration of the transistors used in the display panel may be appropriately selected depending on the screen size of the display panel. For example, when single-crystal silicon transistors are used as transistors in the display panel, the display panel can be applied to a screen size having a diagonal size of 0.1 to 3 inches. When LTPS transistors are used as transistors in the display panel, the display panel can be applied to a screen size having a diagonal size of 0.1 to 30 inches, preferably 1 to 30 inches. When LTPO transistors (combination of LTPS transistors and OS transistors) are used in the display panel, the display panel can be applied to a screen size having a diagonal size of 0.1 to 50 inches, preferably 1 to 50 inches. When OS transistors are used as transistors in the display panel, the display panel can be applied to a screen size having a diagonal size of 0.1 to 200 inches, preferably 50 to 100 inches.

[0384] It is very difficult to increase the size of a single-crystal Si transistor due to the size of a single-crystal Si substrate. Furthermore, since a laser crystallization apparatus is used in the manufacturing process of an LTPS transistor, it is difficult to accommodate large screen sizes (typically, screen sizes exceeding 30 inches in diagonal size). On the other hand, since an OS transistor is not restricted by the use of a laser crystallization apparatus or can be manufactured at a relatively low process temperature (typically, 450° C. or lower), it is possible to accommodate display panels with a relatively large area (typically, a diagonal size of 50 inches to 100 inches). Furthermore, LTPO can be applied to display panel sizes (typically, a diagonal size of 1 inch to 50 inches) that are between those of an LTPS transistor and an OS transistor.

[0385] Next, a cross-sectional view of the light emitting and receiving device will be shown in Fig. 10. Fig. 10 shows a cross-sectional view of the light emitting and receiving device shown in Fig. 8A.

[0386] The cross-sectional view of FIG. 10 shows a cross-sectional view of a part of the region including the FPC 713 and the wiring 706, and a part of the display region 701 including the pixel 703(i, j).

[0387] 10 , the light emitting and receiving device 700 has a functional layer 520 between a first substrate 510 and a second substrate 770. The functional layer 520 includes the transistors (M11, M12, M13, M14, M15, M16, M17) and capacitance elements (C2, C3) described in FIG. 9 , as well as wiring (VS, VG, V1, V2, V3, V4, V5) that electrically connect these elements. Note that, in FIG. 10 , the functional layer 520 includes a pixel circuit 530X(i, j), a pixel circuit 530S(i, j), and a drive circuit GD, but is not limited to this.

[0388] Furthermore, the pixel circuits formed in the functional layer 520 (for example, the pixel circuits 530X(i,j) and 530S(i,j) shown in FIG. 10 ) are electrically connected to the light-emitting devices and light-receiving devices formed on the functional layer 520 (for example, the light-emitting devices 550X(i,j) and 550S(i,j) shown in FIG. 10 ). Specifically, the light-emitting devices 550X(i,j) are electrically connected to the pixel circuits 530X(i,j) via wiring 591X, and the light-receiving devices 550S(i,j) are electrically connected to the pixel circuits 530S(i,j) via wiring 591S. Furthermore, an insulating layer 705 is provided on the functional layer 520, the light-emitting devices, and the light-receiving devices, and the insulating layer 705 functions to bond the second substrate 770 and the functional layer 520 together.

[0389] Note that a substrate provided with touch sensors arranged in a matrix can be used as the second substrate 770. For example, a substrate provided with a capacitive touch sensor or an optical touch sensor can be used as the second substrate 770. In this way, the light-emitting and receiving device of one embodiment of the present invention can be used as a touch panel.

[0390] Note that the structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiments.

[0391] Embodiment 5 In this embodiment, structures of electronic devices of one embodiment of the present invention will be described with reference to FIGS. 11A to 13B. FIG.

[0392] 11A to 13B are diagrams illustrating the structure of an electronic device of one embodiment of the present invention. FIG. 11A is a block diagram of the electronic device, and FIGS. 11B to 11E are perspective views illustrating the structure of the electronic device. FIGS. 12A to 12E are perspective views illustrating the structure of the electronic device. FIGS. 13A and 13B are perspective views illustrating the structure of the electronic device.

[0393] An electronic device 5200B described in this embodiment includes an arithmetic device 5210 and an input / output device 5220 (see FIG. 11A).

[0394] The arithmetic unit 5210 has a function of receiving operation information and a function of supplying image information based on the operation information.

[0395] The input / output device 5220 has a display unit 5230, an input unit 5240, a detection unit 5250, a communication unit 5290, a function to supply operation information, and a function to be supplied with image information. The input / output device 5220 also has a function to supply detection information, a function to supply communication information, and a function to be supplied with communication information.

[0396] The input unit 5240 has a function of supplying operation information. For example, the input unit 5240 supplies operation information based on an operation by the user of the electronic device 5200B.

[0397] Specifically, the input unit 5240 can use a keyboard, hardware buttons, a pointing device, a touch sensor, an illuminance sensor, an imaging device, a voice input device, an eye-gaze input device, an attitude detection device, or the like.

[0398] The display portion 5230 has a function of displaying a display panel and displaying image information. For example, the display panel described in Embodiment 3 can be used as the display portion 5230.

[0399] The detection unit 5250 has a function of supplying detection information, for example, a function of detecting the surrounding environment in which the electronic device is used and supplying the detected information.

[0400] Specifically, an illuminance sensor, an imaging device, a posture detection device, a pressure sensor, a human sensor, or the like can be used for the detection unit 5250 .

[0401] The communication unit 5290 has a function of receiving and supplying communication information. For example, it has a function of connecting to other electronic devices or communication networks by wireless communication or wired communication. Specifically, it has functions such as wireless local area communication, telephone communication, and short-range wireless communication.

[0402] FIG. 11B shows an electronic device having an outer shape that conforms to a cylindrical pillar or the like. An example of such an electronic device is a digital signage device. The display panel of one embodiment of the present invention can be applied to the display portion 5230. Note that the display panel may have a function of changing the display method depending on the illuminance of the usage environment. Furthermore, the display panel may have a function of detecting the presence of a person and changing the display content. This allows the display panel to be installed on a pillar of a building, for example. Alternatively, advertisements, notices, or the like can be displayed.

[0403] 11C shows an electronic device having a function of generating image information based on the trajectory of a pointer used by a user. Examples include an electronic whiteboard, an electronic bulletin board, and an electronic signboard. Specifically, a display panel with a diagonal length of 20 inches or more, preferably 40 inches or more, and more preferably 55 inches or more can be used. Alternatively, multiple display panels can be arranged to form a single display area. Alternatively, multiple display panels can be arranged to form a multi-screen.

[0404] 11D shows an electronic device that can receive information from another device and display it on the display unit 5230. An example is a wearable electronic device. Specifically, several options can be displayed, or the user can select several options and send a reply to the sender of the information. Alternatively, the electronic device may have a function to change the display method depending on the illuminance of the usage environment. This can reduce the power consumption of the wearable electronic device, for example. Alternatively, an image can be displayed on the wearable electronic device so that the electronic device can be used effectively even in environments with strong external light, such as outdoors on a sunny day.

[0405] 11E shows an electronic device having a display unit 5230 with a curved surface that gently curves along the side of the housing. An example is a mobile phone. The display unit 5230 includes a display panel that has a function of displaying information on, for example, the front, side, top, and back of the mobile phone. This allows information to be displayed not only on the front of the mobile phone, but also on the side, top, and back.

[0406] 12A shows an electronic device that can receive information from the Internet and display it on the display unit 5230. An example of such an electronic device is a smartphone. For example, a created message can be checked on the display unit 5230. Alternatively, the created message can be transmitted to another device. Alternatively, the smartphone has a function of changing the display method depending on the illuminance of the usage environment. This can reduce the power consumption of the smartphone. Alternatively, for example, an image can be displayed on the smartphone so that the smartphone can be used in an environment with strong external light, such as outdoors on a sunny day.

[0407] FIG. 12B shows an electronic device that can use a remote controller as the input unit 5240. An example is a television system. Alternatively, information can be received from a broadcasting station or the Internet and displayed on the display unit 5230. Alternatively, a user can be photographed using the detection unit 5250. An image of the user can be transmitted. Alternatively, the user's viewing history can be acquired and provided to a cloud service. Alternatively, recommendation information can be acquired from a cloud service and displayed on the display unit 5230. Programs or videos can be displayed based on the recommendation information. Alternatively, the device has a function to change the display method depending on the illuminance of the usage environment, for example. This allows images to be displayed on the television system so that it can be used appropriately even when strong external light shines indoors on a sunny day.

[0408] 12C shows an electronic device that can receive learning materials from the Internet and display them on the display unit 5230. One example is a tablet computer. Alternatively, a report can be input using the input unit 5240 and sent to the Internet. Alternatively, the results of corrections or evaluations of the report can be obtained from a cloud service and displayed on the display unit 5230. Alternatively, suitable learning materials can be selected and displayed based on the evaluations.

[0409] For example, an image signal can be received from another electronic device and displayed on the display unit 5230. Alternatively, the display unit 5230 can be used as a sub-display by being placed on a stand or the like. This allows images to be displayed on the tablet computer so that the tablet computer can be used suitably even in an environment with strong external light, such as outdoors on a sunny day.

[0410] FIG. 12D shows an electronic device having multiple display units 5230. An example is a digital camera. For example, an image can be captured by the detection unit 5250 and displayed on the display unit 5230. Alternatively, the captured image can be displayed on the detection unit. Alternatively, the captured image can be decorated using the input unit 5240. Alternatively, a message can be attached to the captured image. Alternatively, the captured image can be transmitted to the Internet. Alternatively, the electronic device has a function to change the capture conditions depending on the illuminance of the usage environment. This allows the subject to be displayed on the digital camera so that it can be viewed appropriately even in an environment with strong external light, such as outdoors on a sunny day.

[0411] 12E shows an electronic device that can control another electronic device using the electronic device of this embodiment as a master, with the other electronic device used as a slave. One example is a portable personal computer. For example, part of the image information can be displayed on the display unit 5230, and another part of the image information can be displayed on the display unit of the other electronic device. Alternatively, an image signal can be supplied. Alternatively, information to be written can be obtained from the input unit of the other electronic device using the communication unit 5290. This allows, for example, a portable personal computer to utilize a large display area.

[0412] FIG. 13A shows an electronic device having a detection unit 5250 that detects acceleration or orientation. An example is a goggle-type electronic device. Alternatively, the detection unit 5250 can provide information related to the user's position or the direction the user is facing. Alternatively, the electronic device can generate image information for the right eye and image information for the left eye based on the user's position or the direction the user is facing. Alternatively, the display unit 5230 has a display area for the right eye and a display area for the left eye. This allows, for example, an image of a virtual reality space that provides an immersive experience to be displayed on the goggle-type electronic device.

[0413] 13B shows an electronic device having a detection unit 5250 that detects an imaging device, acceleration, or orientation. An example is a glasses-type electronic device. Alternatively, the detection unit 5250 can provide information related to the user's position or the direction the user is facing. Alternatively, the electronic device can generate image information based on the user's position or the direction the user is facing. This allows, for example, information to be attached to a real-world scene and displayed. Alternatively, an image of an augmented reality space can be displayed on the glasses-type electronic device.

[0414] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0415] In this embodiment, a structure in which the light-emitting device described in Embodiment 2 is used as a lighting device will be described with reference to Fig. 14. Fig. 14A is a cross-sectional view taken along line e-f in the top view of the lighting device shown in Fig. 14B.

[0416] In the lighting device of this embodiment, a first electrode 401 is formed over a light-transmitting substrate 400 which serves as a support. The first electrode 401 corresponds to the first electrode 101 in Embodiment 2. When light is extracted from the first electrode 401 side, the first electrode 401 is formed using a light-transmitting material.

[0417] A pad 412 for supplying a voltage to the second electrode 404 is formed on the substrate 400 .

[0418] An EL layer 403 is formed over the first electrode 401. The EL layer 403 has a structure corresponding to the EL layer 103 in Embodiment Mode 2. For the structure thereof, refer to the description therein.

[0419] A second electrode 404 is formed to cover the EL layer 403. The second electrode 404 corresponds to the second electrode 102 in Embodiment Mode 2. When light is extracted from the first electrode 401 side, the second electrode 404 is formed using a material with high reflectivity. The second electrode 404 is connected to a pad 412 to supply a voltage.

[0420] As described above, the lighting device described in this embodiment has a light-emitting device including the first electrode 401, the EL layer 403, and the second electrode 404. Since the light-emitting device has high emission efficiency, the lighting device in this embodiment can have low power consumption.

[0421] The substrate 400 on which the light-emitting device having the above configuration is formed is fixed to a sealing substrate 407 using sealing materials (405, 406), thereby completing the lighting device. Either one of the sealing materials 405 or 406 can be used. Also, a desiccant can be mixed into the inner sealing material 406 (not shown in FIG. 14B ), which can absorb moisture and improve reliability.

[0422] Furthermore, the pad 412 and a part of the first electrode 401 can be provided as an external input terminal by extending them outside the sealing materials 405 and 406. An IC chip 420 or the like on which a converter or the like is mounted may also be provided thereon.

[0423] Embodiment 7 In this embodiment, an application example of a lighting device manufactured using a light-emitting device which is one embodiment of the present invention or a light-emitting device which is a part of the light-emitting device will be described with reference to FIGS.

[0424] The indoor lighting device can be applied as a ceiling light 8001. Ceiling lights 8001 are available in direct ceiling mount and recessed ceiling types. Such lighting devices are constructed by combining a light emitting device with a housing and a cover. It can also be applied to cord pendant types (hanging from the ceiling with a cord).

[0425] The foot lamp 8002 can also project light onto the floor, improving safety around the feet. For example, it is effective for use in bedrooms, stairs, and corridors. In this case, the size and shape can be changed appropriately depending on the size and structure of the room. It can also be used as a stationary lighting device configured by combining a light-emitting device with a support base.

[0426] The sheet lighting 8003 is a thin sheet-like lighting device. Since it is attached to a wall surface, it does not take up much space and can be used for a wide range of purposes. It can also be easily made larger. It can also be used on curved walls, housings, etc.

[0427] It is also possible to use a lighting device 8004 in which light from a light source is controlled to only a desired direction.

[0428] The desk lamp 8005 includes a light source 8006 , and the light-emitting device according to one embodiment of the present invention or a light-emitting device that is a part of the light-emitting device can be used as the light source 8006 .

[0429] In addition to the above, by applying the light-emitting device of one embodiment of the present invention or a light-emitting device that is a part of the light-emitting device to a part of furniture installed in a room, the lighting device can have the function of the furniture.

[0430] As described above, various lighting devices using the light-emitting device can be obtained. Note that these lighting devices are included in one embodiment of the present invention.

[0431] The structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiments.

[0432] 16 will be described as an example of a light-emitting device and a light-receiving device that can be applied to a light-emitting device according to one embodiment of the present invention. Note that the light-emitting and receiving device 810 can be called a light-emitting device because it includes a light-emitting device, and can be called a light-receiving device because it includes a light-receiving device. Furthermore, since the light-emitting and receiving device 810 can be applied to a display portion of an electronic device or the like, it can also be called a display panel or a display device.

[0433] FIG. 16A is a schematic cross-sectional view of a light-emitting device 805a and a light-receiving device 805b included in a light-emitting and light-receiving device 810 of one embodiment of the present invention.

[0434] The light-emitting device 805a has a function of emitting light (hereinafter also referred to as a light-emitting function). The light-emitting device 805a includes an electrode 801a, an EL layer 803a, and an electrode 802. The light-emitting device 805a is preferably a light-emitting device (organic EL device) that utilizes the organic EL described in Embodiment 2. Therefore, the EL layer 803a sandwiched between the electrode 801a and the electrode 802 includes at least a light-emitting layer. The light-emitting layer includes a light-emitting substance. Light is emitted from the EL layer 803a by applying a voltage between the electrode 801a and the electrode 802. The EL layer 803a may include various layers, such as a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a carrier (hole or electron) blocking layer, and a charge generation layer, in addition to the light-emitting layer.

[0435] The light-receiving device 805b has a function of detecting light (hereinafter also referred to as a light-receiving function). The light-receiving device 805b can be, for example, a pn-type or pin-type photodiode. The light-receiving device 805b has an electrode 801b, a light-receiving layer 803b, and an electrode 802. The light-receiving layer 803b sandwiched between the electrode 801b and the electrode 802 has at least an active layer. The light-receiving layer 803b can also be made of the same materials as those used in the various layers of the EL layer 803a described above (hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, carrier (hole or electron) blocking layer, charge generation layer, etc.). The light-receiving device 805b functions as a photoelectric conversion device, generating charges by light incident on the light-receiving layer 803b and extracting them as current. At this time, a voltage may be applied between the electrode 801b and the electrode 802. The amount of generated charge is determined based on the amount of light incident on the light receiving layer 803b.

[0436] The light receiving device 805b has a function of detecting visible light. The light receiving device 805b is sensitive to visible light. It is more preferable that the light receiving device 805b has a function of detecting visible light and infrared light. It is preferable that the light receiving device 805b is sensitive to visible light and infrared light.

[0437] In this specification, the blue (B) wavelength region is defined as 400 nm or more and less than 490 nm, and blue (B) light has at least one emission spectrum peak in this wavelength region. The green (G) wavelength region is defined as 490 nm or more and less than 580 nm, and green (G) light has at least one emission spectrum peak in this wavelength region. The red (R) wavelength region is defined as 580 nm or more and less than 700 nm, and red (R) light has at least one emission spectrum peak in this wavelength region. In this specification, the visible light wavelength region is defined as 400 nm or more and less than 700 nm, and visible light has at least one emission spectrum peak in this wavelength region. The infrared (IR) wavelength region is defined as 700 nm or more and less than 900 nm, and infrared (IR) light has at least one emission spectrum peak in this wavelength region.

[0438] The active layer of the light-receiving device 805b includes a semiconductor. Examples of the semiconductor include inorganic semiconductors such as silicon and organic semiconductors containing organic compounds. The light-receiving device 805b preferably uses an organic semiconductor device (or an organic photodiode) whose active layer includes an organic semiconductor. Organic photodiodes can be easily thinned, lightweight, and enlarged, and have high flexibility in shape and design, making them applicable to various display devices. Furthermore, using an organic semiconductor is preferable because the EL layer 803a of the light-emitting device 805a and the light-receiving layer 803b of the light-receiving device 805b can be formed by the same method (e.g., vacuum evaporation) and can use a common manufacturing equipment. The light-receiving layer 803b of the light-receiving device 805b can be formed using an organic compound according to one embodiment of the present invention.

[0439] In a display device according to one embodiment of the present invention, an organic EL device can be used as the light-emitting device 805a, and an organic photodiode can be used as the light-receiving device 805b. The organic EL device and the organic photodiode can be formed over the same substrate. Therefore, an organic photodiode can be built into a display device using an organic EL device. The display device according to one embodiment of the present invention has one or both of an imaging function and a sensing function in addition to a function of displaying an image.

[0440] The electrode 801a and the electrode 801b are provided on the same surface. Fig. 16A shows a configuration in which the electrode 801a and the electrode 801b are provided on a substrate 800. Note that the electrode 801a and the electrode 801b can be formed, for example, by processing a conductive film formed on the substrate 800 into an island shape. In other words, the electrode 801a and the electrode 801b can be formed through the same process.

[0441] A heat-resistant substrate capable of withstanding the formation of the light-emitting device 805 a and the light-receiving device 805 b can be used as the substrate 800. When an insulating substrate is used as the substrate 800, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, an organic resin substrate, or the like can be used. In addition, a semiconductor substrate such as a single-crystal semiconductor substrate made of silicon, silicon carbide, or the like, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, or an SOI substrate can be used.

[0442] In particular, it is preferable to use the above-mentioned insulating substrate or a substrate on which a semiconductor circuit including a semiconductor element such as a transistor is formed as the substrate 800. The semiconductor circuit preferably constitutes, for example, a pixel circuit, a gate line driving circuit (gate driver), a source line driving circuit (source driver), etc. In addition to the above, an arithmetic circuit, a memory circuit, etc. may also be configured.

[0443] The electrode 802 is an electrode made of a layer common to the light-emitting device 805 a and the light-receiving device 805 b. Of these electrodes, a conductive film that transmits visible light and infrared light is used for the electrode on the side that emits or receives light. It is preferable to use a conductive film that reflects visible light and infrared light for the electrode on the side that does not emit or receive light.

[0444] The electrode 802 in the display device which is one embodiment of the present invention functions as one electrode of each of the light-emitting device 805a and the light-receiving device 805b.

[0445] 16B shows a case where electrode 801a of light-emitting device 805a has a higher potential than electrode 802. In this case, electrode 801a functions as the anode of light-emitting device 805a, and electrode 802 functions as the cathode. Furthermore, electrode 801b of light-receiving device 805b has a lower potential than electrode 802. Note that in FIG. 16B, to make it easier to understand the direction of current flow, the circuit symbol for a light-emitting diode is shown to the left of light-emitting device 805a, and the circuit symbol for a photodiode is shown to the right of light-receiving device 805b. Furthermore, the direction of carrier (electron and hole) flow is schematically indicated by arrows in each device.

[0446] In the configuration shown in FIG. 16B, when a first potential is supplied to electrode 801a via a first wiring, a second potential is supplied to electrode 802 via a second wiring, and a third potential is supplied to electrode 801b via a third wiring, the relationship in magnitude of each potential is first potential > second potential > third potential.

[0447] 16C shows a case where electrode 801a of light-emitting device 805a has a lower potential than electrode 802. In this case, electrode 801a functions as the cathode of light-emitting device 805a, and electrode 802 functions as the anode. Electrode 801b of light-receiving device 805b has a lower potential than electrode 802 and a higher potential than electrode 801a. In FIG. 16C, to make it easier to understand the direction of current flow, the circuit symbol for a light-emitting diode is shown to the left of light-emitting device 805a, and the circuit symbol for a photodiode is shown to the right of light-receiving device 805b. The direction of carrier (electron and hole) flow is also indicated by arrows in each device.

[0448] In the configuration shown in FIG. 16C, when a first potential is supplied to electrode 801a via a first wiring, a second potential is supplied to electrode 802 via a second wiring, and a third potential is supplied to electrode 801b via a third wiring, the relationship in magnitude of each potential is second potential > third potential > first potential.

[0449] 17A shows a light-receiving and light-emitting device 810A, which is a modified example of the light-receiving and light-emitting device 810. The light-receiving and light-emitting device 810A differs from the light-receiving and light-emitting device 810 in that it includes a common layer 806 and a common layer 807. In the light-emitting device 805a, the common layer 806 and the common layer 807 function as part of the EL layer 803a. In the light-receiving device 805b, the common layer 806 and the common layer 807 function as part of the light-receiving layer 803b. The common layer 806 includes, for example, a hole injection layer and a hole transport layer. The common layer 807 includes, for example, an electron transport layer and an electron injection layer.

[0450] By adopting a configuration including the common layer 806 and the common layer 807, it is possible to incorporate a light receiving device without significantly increasing the number of times of coating, and it is possible to manufacture the light receiving and emitting device 810A with high throughput.

[0451] FIG. 17B shows a light-receiving and light-emitting device 810B, which is a modification of the light-receiving and light-emitting device 810A. The light-receiving and light-emitting device 810B differs from the light-receiving and light-emitting device 810A in that the EL layer 803a includes layers 806a and 807a, and the light-receiving layer 803b includes layers 806b and 807b. The layers 806a and 806b are made of different materials and include, for example, a hole injection layer and a hole transport layer. The layers 806a and 806b may be made of the same material. The layers 807a and 807b are made of different materials and include, for example, an electron transport layer and an electron injection layer. The layers 807a and 807b may be made of the same material.

[0452] By selecting the most suitable materials for constituting the light-emitting device 805a for the layers 806a and 807a, and the most suitable materials for constituting the light-receiving device 805b for the layers 806b and 807b, the performance of each of the light-emitting device 805a and the light-receiving device 805b in the light-receiving and light-emitting device 810B can be improved.

[0453] Note that the resolution of the light-receiving device 805b described in this embodiment can be 100 ppi or more, preferably 200 ppi or more, more preferably 300 ppi or more, more preferably 400 ppi or more, and further preferably 500 ppi or more, and can be 2000 ppi or less, 1000 ppi or less, or 600 ppi or less. In particular, when the light-receiving device 805b is arranged with a resolution of 200 ppi to 600 ppi, preferably 300 ppi to 600 ppi, the light-receiving device 805b can be suitably used for imaging a fingerprint. When fingerprint authentication is performed using the display device of one embodiment of the present invention, increasing the resolution of the light-receiving device 805b enables, for example, extraction of fingerprint minutia with high accuracy, thereby improving the accuracy of fingerprint authentication. Furthermore, a resolution of 500 ppi or higher is preferable because it allows compliance with standards such as those of the National Institute of Standards and Technology (NIST). Assuming that the resolution of the light-receiving device is 500 ppi, the size per pixel is 50.8 μm, which is sufficient resolution for capturing an image of the width of a fingerprint (typically, 300 μm to 500 μm).

[0454] The structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiments.

[0455] <Synthesis Example 1> In this Synthesis Example, a synthesis method for 2-[3-(dibenzo[f,h]quinoxalin-2-yl)-5-(9-phenanthren-9-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: Pn-mDBqPTzn) shown as structural formula (100) in Embodiment 1 will be specifically described.

[0456]

[0457] <Step 1: Synthesis of 2-[3-chloro-5-(9-phenanthrenyl)phenyl]-4,6-diphenyl-1,3,5-triazine> Step 1 was carried out as follows: The synthesis scheme is shown in formula (A-1).

[0458] First, 5.1 g (12 mmol) of 2-(3-bromo-5-chlorophenyl)-4,6-diphenyl-1,3,5-triazine, 2.7 g (12 mmol) of 9-phenanthreneboronic acid, and potassium carbonate (abbreviation: K ２ CO ３ 4.0 g (29 mmol) of bis(triphenylphosphine)palladium(II) dichloride (abbreviated as Pd(PPh)), 70 mL of toluene, 10 mL of ethanol, and 10 mL of water were added. The mixture was then stirred under reduced pressure to degas the mixture, and the atmosphere in the flask was replaced with nitrogen. The mixture was then heated to 70°C under a nitrogen stream to obtain bis(triphenylphosphine)palladium(II) dichloride (abbreviated as Pd(PPh)). ３ ) ２ Cl ２ After adding 0.42 g (0.60 mmol) of methylpropanol, the mixture was heated to 90°C and refluxed with stirring for 4 hours. After the reaction, water was added to the mixture, which was then filtered under suction. The residue was washed with water and ethanol. Toluene was added to the residue, which was then heated to dissolve the residue, and the residue was filtered through Celite and alumina. The filtrate was concentrated and dried to obtain 5.0 g of a white solid (yield 79%).

[0459]

[0460] <Step 2: Synthesis of 2-[3-(9-phenanthrenyl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-4,6-diphenyl-1,3,5-triazine> Step 2 was carried out as follows: The synthetic scheme is shown in formula (A-2).

[0461] First, 2.6 g (4.9 mmol) of 2-[3-chloro-5-(9-phenanthrenyl)phenyl]-4,6-diphenyl-1,3,5-triazine obtained in Step 1, 1.9 g (7.4 mmol) of bis(pinacolato)diboron, 1.4 g (15 mmol) of potassium acetate (abbreviation: KOAc), 47 mg (10 μmol) of 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (abbreviation: Xphos), and 50 mL of 1,4-dioxane were added to a 200 mL three-neck flask. Next, this mixture was stirred and degassed under reduced pressure, and the atmosphere in the flask was replaced with nitrogen. Next, the flask was heated to 70° C. under a nitrogen stream, and palladium acetate (abbreviation: Pd(OAc) ２ After adding 11 mg (50 μmol) of )), the mixture was heated to 100° C. and refluxed with stirring for 9 hours. After the reaction, the mixture was filtered under suction, and the resulting filtrate was extracted with ethyl acetate and washed with water. The resulting organic layer was washed with saturated brine, dried over magnesium sulfate, and then concentrated to obtain 2.4 g of a white solid (yield 80%).

[0462]

[0463] <Step 3: Synthesis of Pn-mDBqPTzn> Step 3 was carried out according to the following procedure: The synthesis scheme is shown in formula (A-2).

[0464] First, a 200 mL three-neck flask was charged with 0.83 g (3.1 mmol) of 2-chloro-dibenzoquinoxaline, 1.9 g (3.1 mmol) of the compound obtained in Step 2, 1.0 g (7.2 mmol) of potassium carbonate, and tris(2-methylphenyl)phosphine (abbreviation: P(o-tolyl) ３0.10 g (0.33 mmol) of methyl methyl ketone, 40 mL of toluene, 5 mL of ethanol, and 5 mL of water were added. Next, this mixture was stirred and degassed under reduced pressure, and the atmosphere in the flask was replaced with nitrogen. Next, the mixture was heated to 70°C under a nitrogen stream, and 15 mg (70 μmol) of palladium acetate was added. After that, the temperature was raised to 90°C and the mixture was refluxed with stirring for 2.5 hours. After the reaction, the mixture was filtered with suction, and the residue was washed with water and ethanol. Toluene was added to the obtained residue, and the mixture was heated to 50°C and then filtered with suction. The obtained residue was concentrated and dried to obtain 2.0 g of a white solid (yield 90%).

[0465]

[0466] <Sublimation purification> 2.0 g of the obtained white solid was heated by train sublimation at a pressure of 2.8 Pa, an argon flow rate of 15 mL / min and 360° C. for 14 hours to obtain 1.0 g of a white solid (recovery rate 50%).

[0467] The obtained white solid was dissolved in deuterated 1,1,2,2-tetrachloroethane (abbreviated as TCE-d2) and analyzed by nuclear magnetic resonance spectroscopy ( １ The results of the analysis by H-NMR are shown below. １ The H-NMR chart is shown in Figure 18 (Figure 18A shows δ = 0 to 12 ppm, and Figure 18B shows δ = 7.0 to 10.0 ppm (enlarged view)). From these results, it was found that Pn-mDBqPTzn, an organic compound of the present invention, was obtained in this synthesis example.

[0468] １ H-NMR (TCE-d2, 500MHz): δ = 7.60-7.86 (m, 14H), 7.99 (s, 1H), 8.05 (dd, 2H), 8.67 (d, 2H ), 8.81-8.89 (m, 7H), 9.09 (s, 1H), 9.27 (d, 1H), 9.44 (d, 1H), 9.72 (s, 1H), 9.86 (s, 1H).

[0469] ​<Measurement of Emission Spectrum and Absorption Spectrum of Pn-mDBqPTzn> The absorption spectrum and emission spectrum of Pn-mDBqPTzn were measured. The absorption spectrum was measured using an ultraviolet-visible spectrophotometer (U-4100 manufactured by Hitachi, Ltd.). The emission spectrum was measured using a fluorometer (FP-8600 manufactured by JASCO Corporation).

[0470] The absorption spectrum and emission spectrum of a dichloromethane solution of Pn-mDBqPTzn are shown in Figure 19. The absorption spectrum in the solution state was obtained by subtracting the absorption spectrum measured by placing only the solvent (dichloromethane) in a quartz cell from the absorption spectrum measured by placing a solution of Pn-mDBqPTzn in the quartz cell.

[0471] The absorption and emission spectra of the thin film are shown in Figure 20. The solid thin film was prepared by vacuum deposition on a quartz substrate and sealed using a quartz substrate as the counter substrate to prepare a measurement sample. The emission spectrum was measured for the sealed sample, while the absorption spectrum was measured for the sample after removing the sealing and counter substrate. The absorption spectrum of the thin film was obtained by subtracting the absorption spectrum of the quartz substrate from the absorption spectrum of Pn-mDBqPTzn formed on the quartz substrate. The prepared thin film showed no visible changes in film quality even after the sealing was removed at room temperature, confirming that it remained a stable amorphous film. These results demonstrate that the compound of the present application can provide a thin film with excellent stability, and that organic devices prepared using the compound of the present application exhibit excellent stability.

[0472] As shown in Figure 19, the dichloromethane solution of Pn-mDBqPTzn exhibited absorption peaks near 375 nm, 364 nm, and 260 nm, and an emission peak near 392 nm (excitation wavelength 260 nm). Furthermore, as shown in Figure 20, the thin film of Pn-mDBqPTzn exhibited absorption peaks near 390 nm, 370 nm, and 269 nm, and an emission peak near 438 nm (excitation wavelength 385 nm). These results demonstrate that Pn-mDBqPTzn can be effectively used as a host material for use with luminescent materials or visible-light-emitting materials. It can also be effectively used as a capping layer on a cathode. When used as these layers, the absorption peak is preferably 300 nm or more and 450 nm or less, more preferably 320 nm or more and 380 nm or less. The emission peak is preferably 350 nm or more and 650 nm or less, more preferably 380 nm or more and 500 nm or less.

[0473] <Measurement of Tg of Pn-mDBqPTzn> The glass transition temperature (Tg) of Pn-mDBqPTzn was measured. Tg was measured using a differential scanning calorimeter (PYRIS1 DSC, manufactured by PerkinElmer Japan Co., Ltd.) by placing the powder on an aluminum cell. As a result, the Tg of Pn-mDBqPTzn was found to be 161°C. This demonstrates that the compound of the present invention exhibits extremely high thermal properties, and thin films prepared using such compounds are expected to have stable film quality. By using a compound capable of forming a thin film with stable film quality in an organic device, it is possible to provide an organic device with high heat resistance.

[0474] Furthermore, in organic devices such as light-emitting devices and light-receiving devices, it is preferable that the resistance (heat resistance, film quality stability, etc.) of upper layers is high. This is because, when forming an organic device, upper layers may be more significantly affected by the process. For example, when the compound of the present application is used as an electron transport layer, it is desirable that the Tg be 5°C or more, more preferably 10°C or more, higher than that of the host material of the underlying light-emitting layer. It is also effective to have a Tg that is 5°C or more, more preferably 10°C or more, higher than that of the material of the underlying hole transport layer or hole injection layer. A layer (electron transport layer such as a hole blocking layer) may be provided between the light-emitting layer and the electron transport layer, and in this case, it is also preferable that the Tg of the electron transport layer be higher than that of the hole blocking layer.

[0475] <Calculation of HOMO and LUMO of Pn-mDBqPTzn> The HOMO level and LUMO level of Pn-mDBqPTzn were calculated based on cyclic voltammetry (CV) measurements. The calculation method is shown below.

[0476] The measurement device used was an electrochemical analyzer (manufactured by BAS Co., Ltd., model number: ALS Model 600A or 600C). The solution used in the CV measurement was dehydrated dimethylformamide (DMF) (manufactured by Aldrich Co., Ltd., 99.8%, catalog number: 22705-6) as the solvent and tetra-n-butylammonium perchlorate (n-BuCl ) as the supporting electrolyte. ４ NClO ４ ) (Tokyo Chemical Industry Co., Ltd., catalog number: T0836) was dissolved to a concentration of 100 mmol / L, and the measurement target was further dissolved to a concentration of 2 mmol / L.

[0477] The working electrode was a platinum electrode (PTE platinum electrode, manufactured by BAS Co., Ltd.), the auxiliary electrode was a platinum electrode (Pt counter electrode (5 cm) for VC-3, manufactured by BAS Co., Ltd.), and the reference electrode was an Ag / Ag ＋ An electrode (RE7 non-aqueous solvent reference electrode, manufactured by BAS Co., Ltd.) was used. The measurements were carried out at room temperature (20° C. or higher and 25° C. or lower).

[0478] The scan rate during CV measurement was standardized to 0.1 V / sec, and the oxidation potential Ea [V] and reduction potential Ec [V] relative to the reference electrode were measured. Ea was the midpoint potential of the oxidation-reduction wave, and Ec was the midpoint potential of the reduction-oxidation wave. Here, since the potential energy of the reference electrode used in this example relative to the vacuum level is known to be -4.94 [eV], the HOMO level and LUMO level can be calculated from the formulas HOMO level [eV] = -4.94 - Ea and LUMO level [eV] = -4.94 - Ec, respectively.

[0479] In addition, the CV measurement was repeated 100 times, and the oxidation-reduction wave in the 100th cycle measurement was compared with the oxidation-reduction wave in the first cycle to examine the electrical stability of the compound.

[0480] As a result, it was found that the oxidation potential Ea [V] of Pn-mDBqPTzn was below the lower limit of measurement by the device, and from this it was estimated that the HOMO level was −6.4 eV or less. On the other hand, from the measurement result of the reduction potential Ec [V], it was found that the LUMO level was −3.04 eV.

[0481] It is believed that the LUMO level allows electrons to be donated and received favorably, and the compound can be suitably used in an electron transport layer, a light-emitting layer in an organic device, or a charge generation layer in a tandem device.

[0482] Furthermore, when used as an electron transport layer of an organic device, the LUMO level of the electron transport layer material is preferably lower than that of the light-emitting layer host material. Furthermore, the LUMO level of the electron transport layer material is preferably lower than that of the cap layer material. In particular, the LUMO level relationship is preferably cap layer material > light-emitting layer host material > electron transport layer material. When multiple light-emitting devices (e.g., red device, blue device, green device) are used, it is preferable that the LUMO level relationship be satisfied in each light-emitting device.

[0483] <Measurement of refractive index of Pn-mDBqPTzn> The refractive index of Pn-mDBqPTzn was measured using a spectroscopic ellipsometer (M-2000U manufactured by J.A. Woollam Japan). For the measurement, a film of Pn-mDBqPTzn was formed on a quartz substrate by vacuum deposition to a thickness of approximately 50 nm. At a wavelength of 633 nm, nOrdinary (n Ｏ The refractive index was 1.85. As a result, it was found that Pn-mDBqPTzn can be effectively used as a host material, a hole transport material, an electron transport material, or a capping layer material provided on a cathode. When used as a capping layer material, the refractive index is preferably 1.75 or more and 2.50 or less.

[0484] Furthermore, when used as a hole transport material or an electron transport material, the luminous efficiency can be further increased by lowering the refractive index. As a method for lowering the refractive index, the refractive index can be adjusted to 1.50 or more and 1.85 or less by adding an alkyl group as a substituent to the compound of the present invention. For example, in the case of the general formulas (G1) to (G4), R １ ~R ４ It is preferred that at least one of them has an alkyl group.

[0485] Furthermore, when the compound of the present application is used as a host material, a hole transport layer material, or an electron transport layer material, it is preferable that the refractive index of the compound of the present application is lower than that of the cap layer material or the host material of the light-emitting layer. Specifically, the refractive index of the compound of the present application is lower than that of the cap layer by 0.1 or more, more preferably by 0.2 or more. Furthermore, the refractive index of the compound of the present application is lower than that of the host material of the light-emitting layer by 0.1 or more, more preferably by 0.2 or more. In particular, when the compound of the present application is used as an electron transport layer material, the luminous efficiency can be increased by lowering the refractive index than that of the cap layer and the light-emitting layer.

[0486] Synthesis Example 2 In this synthesis example, a method for synthesizing 2-[3-(2,6-dimethyl-3-pyridinyl)-5-(9-phenanthrenyl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mPn-mDMePyPTzn), an organic compound that can be used as a material (e.g., an electron transport material, a host material, etc.) that can constitute an organic device and is represented by structural formula (160), will be described.

[0487] mPn-mDMePyPTzn was produced in the same manner as in Synthesis Example 1, except that 3-bromo-2,6-dimethylpyridine was used instead of 2-chloro-dibenzoquinoxaline in Step 3 of Synthesis Example 1. The synthesis scheme is shown in Formula (B-1). The heating time was 5 hours, and the heating temperature was 65°C.

[0488]

[0489] The absorption and emission spectra of a light-emitting device using mPn-mDMePyPTzn were measured in the same manner as in Example 1. The peak wavelengths of the absorption spectrum in the solution state were 256 nm and 350 nm, and the peak wavelength of the emission spectrum was 436 nm. The peak wavelength of the absorption spectrum in the thin film state was 336 nm, and the peak wavelength of the emission spectrum was 409 nm (excitation wavelength 310 nm).

[0490] Furthermore, the Tg of mPn-mDMePyPTzn was measured in the same manner as in Example 1 and was found to be 121°C.

[0491] <Synthesis Example 3> In this synthesis example, a synthesis method for 2-[(1,1'-biphenyl)-4-yl]-4-phenyl-6-[9,9'-spirobi(9H-fluoren)-2-yl]-1,3,5-triazine (abbreviation: BP-SFTzn), an organic compound usable as a material (e.g., electron transport material, host material, etc.) that can constitute an organic device and shown as structural formula (440), will be described. The synthesis scheme is shown in formula (C-1).

[0492] A 200 mL three-neck flask was charged with 1.7 g (4.8 mmol) of 2-(biphenyl-4-yl)-4-chloro-6-phenyl-1,3,5-triazine, 2.1 g (5.8 mmol) of 9,9'-spirobi[9H-fluorene]-2-boronic acid, 1.6 g (12 mmol) of potassium carbonate, 50 mL of toluene, 7 mL of ethanol, and 7 mL of water. The mixture was then stirred and degassed under reduced pressure, and the atmosphere in the flask was replaced with nitrogen. The flask was then heated to 70°C under a nitrogen stream, and 0.20 g (0.29 mmol) of bis(triphenylphosphine)palladium(II) dichloride was added. The mixture was then heated to 90°C and refluxed with stirring for 10 hours. Toluene and water were added to the reaction mixture, and the organic layer was extracted. The resulting organic layer was dried over magnesium sulfate, then gravity filtered, and the resulting filtrate was concentrated to obtain a solid. The obtained solid was purified by silica gel column chromatography (developing solvent: toluene:hexane=1:1) and recrystallized from toluene / hexane to obtain 2.7 g (yield 90%) of a white solid, which was the target compound BP-SFTzn.

[0493]

[0494] The absorption spectrum and emission spectrum of BP-SFTzn were measured. Toluene was used as the solvent for the solution measurement. The remaining steps were the same as in Example 1. The peak wavelength of the absorption spectrum in the solution state was 358 nm, and the peak wavelength of the emission spectrum was 388 nm. The peak wavelength of the absorption spectrum of the thin film was 352 nm, and the peak wavelength of the emission spectrum was 419 nm.

[0495] Furthermore, the Tg of BP-SFTzn was measured in the same manner as in Example 1 and was found to be 148°C.

[0496] <Synthesis Example 4> In this synthesis example, a synthesis method for 2-[(1,1′-biphenyl)-4-yl]-4-phenyl-6-{(3′,5′-di-tert-butyl)-1,1′-biphenyl-3-yl}-1,3,5-triazine (abbreviation: BP-SF(4)Tzn), an organic compound that can be used as a material (e.g., an electron transport material, a host material, etc.) that can constitute an organic device and is represented by structural formula (434), will be described.

[0497] BP-SF(4)Tzn was produced in the same manner as in Synthesis Example 3, except that 2-(9,9'-spirobi[9H-fluorene]-4-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane) was used instead of 9,9'-spirobi[9H-fluorene]-2-boronic acid) in Synthesis Example 3. The synthesis scheme is shown in formula (D-1). The heating time was 4.5 hours, and the heating temperature was 90°C.

[0498]

[0499] The absorption and emission spectra of a light-emitting device using BP-SF(4)Tzn were measured in the same manner as in Example 3. The peak wavelength of the absorption spectrum in the solution state was 331 nm, and the peak wavelength of the emission spectrum was 423 nm. The peak wavelength of the absorption spectrum in the thin film state was 357 nm, and the peak wavelength of the emission spectrum was 415 nm.

[0500] The Tg of BP-SF(4)Tzn was measured in the same manner as in Example 1 and was found to be 148°C.

[0501] Synthesis Example 5 In this synthesis example, a method for synthesizing 2,4-bis[4-(1-naphthyl)phenyl]-6-[4-(3-pyridyl)phenyl]pyrimidine (abbreviation: 2,4NP-6PyPPm), an organic compound that can be used as a material (e.g., an electron transport material, a host material, etc.) that can constitute an organic device and is represented by structural formula (424), will be described.

[0502] A 200 mL three-necked flask was charged with 1.1 g (5.8 mmol) of 2,4,6-trichloropyrimidine, 1.2 g (5.8 mmol) of 4-(3-pyridyl)phenylboronic acid, 8.0 g (58 mmol) of potassium carbonate, 80 mL of 1,4-dioxane, and 30 mL of water, and the contents were stirred under reduced pressure to degas the flask, followed by replacement with nitrogen. The contents were then heated to 40° C. under a nitrogen stream, and 0.20 g (0.29 mmol) of bis(triphenylphosphine)palladium(II) dichloride was added and stirred for 6.5 hours to obtain a reaction product containing 4-[4-(3-pyridinyl)phenyl]-2,6-dichloropyrimidine. 3.3 g (13 mmol) of 4-(1-naphthyl)phenylboronic acid was added to the reaction mixture containing 4-[4-(3-pyridinyl)phenyl]-2,6-dichloropyrimidine, and the mixture was stirred and degassed under reduced pressure. The atmosphere in the flask was then replaced with nitrogen. The flask was then heated to 80°C, and 0.20 g (0.29 mmol) of bis(triphenylphosphine)palladium(II) dichloride was added and stirred for 6 hours. Ethyl acetate and water were then added to the reaction mixture to extract the organic layer. The resulting organic layer was dried over magnesium sulfate, and the filtrate obtained by gravity filtration was concentrated to obtain a solid. The resulting solid was purified by silica gel column chromatography (developing solvent: toluene:ethyl acetate = 2:1). The resulting compound was recrystallized from toluene to obtain 2.2 g of a pale yellow solid (yield: 60%). The synthesis scheme is shown in Formula (E-1).

[0503]

[0504] Although the reaction in formula (E-1) was carried out in one step, it can also be carried out in two steps. In this case, the reaction product containing 4-[4-(3-pyridinyl)phenyl]-2,6-dichloropyrimidine is purified (by filtration or the like) to obtain the 4-[4-(3-pyridinyl)phenyl]-2,6-dichloropyrimidine, which is then subjected to a coupling reaction with 4-(1-naphthyl)phenylboronic acid to obtain the target product (2,4NP-6PyPPm).

[0505] The absorption spectrum and emission spectrum of 2,4NP-6PyPPm were measured in the same manner as in Example 3. The peak wavelength of the absorption spectrum in the solution state was 320 nm, and the peak wavelength of the emission spectrum was 387 nm. The peak wavelength of the absorption spectrum in the thin film state was 311 nm, and the peak wavelength of the emission spectrum was 414 nm.

[0506] Furthermore, the Tg of 2,4NP-6PyPPm was measured in the same manner as in Example 1 and was found to be 119°C.

[0507] <Synthesis Example 6> In this synthesis example, a synthesis method for 4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenyl-6-(1,1′-biphenyl-4-yl)pyrimidine (abbreviation: 6BP-4Cz2PPm), an organic compound that can be used as a material (e.g., an electron transport material, a host material, etc.) that can constitute an organic device and is represented by structural formula (404), will be described.

[0508] A 200 mL three-neck flask was charged with 2.9 g (8.3 mmol) of 4-(biphenyl-4-yl)-6-chloro-2-phenylpyrimidine, 4.5 g (10 mmol) of 3,5-di-9H-carbazol-9-ylphenylboronic acid, 2.8 g (20 mmol) of potassium carbonate, 80 mL of toluene, 12 mL of ethanol, and 12 mL of water. The mixture was stirred and degassed under reduced pressure, and the atmosphere in the flask was replaced with nitrogen. The flask was then heated to 70 °C under a nitrogen stream, and 0.35 g (50 μmol) of bis(triphenylphosphine)palladium(II) dichloride was added. The mixture was heated to 90 °C and refluxed with stirring for 6 hours. Water was added to the reaction mixture, and the resulting mixture was suction filtered. The residue was washed with ethanol and water. The residue was dissolved in toluene by heating, and the resulting solution was filtered through Celite and aluminum oxide. The filtrate was concentrated to obtain a solid. The obtained solid was recrystallized from toluene to obtain 5.4 g of a white solid (yield: 90%). The synthesis scheme is shown in formula (F-1).

[0509]

[0510] The absorption spectrum and emission spectrum of 6BP-4Cz2PPm were measured in the same manner as in Example 1. The peak wavelength of the absorption spectrum in the solution state was 296 nm, and the peak wavelength of the emission spectrum was 423 nm. The peak wavelength of the absorption spectrum in the thin film state was 366 nm, and the peak wavelength of the emission spectrum was 425 nm.

[0511] <Synthesis Example 7> In this synthesis example, a synthesis method for 6-(1,1′-biphenyl-3-yl)-4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), an organic compound that can be used as a material (e.g., an electron transport material, a host material, etc.) that can constitute an organic device and is represented by structural formula (405), will be described.

[0512] 6mBP-4Cz2PPm was produced in the same manner as in Synthesis Example 6, except that 4-(biphenyl-3-yl)-6-chloro-2-phenylpyrimidine was used instead of 4-(biphenyl-4-yl)-6-chloro-2-phenylpyrimidine in Synthesis Example 6. The heating time was 11 hours, and the heating temperature was 90° C. The synthesis scheme is shown in general formula (G-1).

[0513]

[0514] The absorption spectrum and emission spectrum of 6mBP-4Cz2PPm were measured in the same manner as in Example 1. The peak wavelength of the absorption spectrum in the solution state was 338 nm, and the peak wavelength of the emission spectrum was 423 nm. The peak wavelength of the absorption spectrum in the thin film state was 3356 nm, and the peak wavelength of the emission spectrum was 423 nm.

[0515] Furthermore, the Tg of 6mBP-4Cz2PPm was measured in the same manner as in Example 1 and was found to be 132°C.

[0516] <Synthesis Example 8> In this synthesis example, a synthesis method for 2-[3′-(9,9-dimethyl-9H-fluoren-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFBPTzn), an organic compound that can be used as a material (e.g., an electron transport material, a host material, etc.) that can constitute an organic device and is represented by structural formula (409), will be described.

[0517] In a 1 L three-neck flask, 15 g (36 mmol) of 2-(3′-chlorobiphenyl-3-yl)-4,6-diphenyl-1,3,5-triazine, 9.1 g (38 mmol) of 9,9-dimethyl-9H-fluorene-2-boronic acid, 0.77 mg (2.1 mmol) of di(1-adamantyl)-n-butylphosphine (also known as cataCXium® A) (abbreviation: cataCXium), and tripotassium phosphate (abbreviation: K ３ P.O. ４ 18 g (86 mmol) of cataCXium and 185 mL of diethylene glycol dimethyl ether (abbreviation: diglyme) were added. The mixture was then stirred and degassed under reduced pressure, and the flask was purged with nitrogen. The flask was then heated to 80°C under a nitrogen stream, and 0.24 mg (1.1 mmol) of palladium acetate was added. The temperature was then raised to 140°C and the mixture was refluxed with stirring for 7 hours. 0.51 g (1.4 mmol) of cataCXium and 0.17 mg (0.75 mmol) of palladium acetate were then added, and the mixture was refluxed with stirring for 8 hours at 150°C. The reactant was dissolved in toluene, filtered through Celite and aluminum oxide, and the resulting filtrate was concentrated to obtain a solid. The resulting solid was purified by silica gel chromatography (developing solvent: toluene:hexane = 2:3). The resulting solid was recrystallized from toluene / hexane to obtain 13 g (64%) of a white solid, the target compound mFBPTzn. The synthesis scheme is shown in formula (H-1).

[0518]

[0519] The absorption spectrum and emission spectrum of mFBPTzn were measured in the same manner as in Example 1. The peak wavelength of the absorption spectrum in the solution state was 315 nm, and the peak wavelength of the emission spectrum was 471 nm. The peak wavelength of the absorption spectrum in the thin film state was 317 nm, and the peak wavelength of the emission spectrum was 410 nm.

[0520] Furthermore, the Tg of mFBPTzn was measured in the same manner as in Example 1 and was found to be 95°C.

[0521] Synthesis Example 9 In this synthesis example, a method for synthesizing 3-[9-(4,6-diphenyl-1,3,5-triazin-2-yl)-2-dibenzofuranyl]-9-phenyl-9H-carbazole (abbreviation: PCDBfTzn), an organic compound that can be used as a material (e.g., an electron transport material, a host material, etc.) that can constitute an organic device and is represented by structural formula (445), will be described.

[0522] A three-neck flask was charged with 2.0 g (4.7 mmol) of 2-(8-chloro-1-dibenzofuranyl)-4,6-diphenyl-1,3,5-triazine, 1.6 g (5.6 mmol) of 9-phenyl-9H-carbazole-3-boronic acid, 85 mg (0.23 mmol) of di(1-adamantyl)-n-butylphosphine, and 3.0 g (14 mmol) of tripotassium phosphate. The atmosphere in the flask was then replaced with nitrogen, and 30 mL of diethylene glycol dimethyl ether was added. The mixture was then stirred and degassed under reduced pressure. The flask was then heated to 80°C, and 18 mg (80 μmol) of palladium acetate was added. The mixture was then heated to 120°C and refluxed with stirring for 14 hours. 50 mg (0.14 mmol) of di(1-adamantyl)-n-butylphosphine and 15 mg (70 μmol) of palladium acetate were then added, and the mixture was refluxed with stirring for 12 hours at 140°C. The reaction mixture was filtered under suction, and the residue was washed with toluene and water. The residue was dissolved in toluene by heating, and the resulting solution was filtered through Celite and aluminum oxide. The filtrate was concentrated to obtain a solid. The resulting solid was recrystallized in toluene to obtain 1.4 g of a yellow solid (yield 45%). The synthesis method is shown in formula (I-1).

[0523]

[0524] The absorption spectrum and emission spectrum of PCDBfTzn were measured in the same manner as in Example 1. The peak wavelength of the absorption spectrum of the thin film was 395 nm, and the peak wavelength of the emission spectrum was 500 nm.

[0525] Furthermore, the Tg of PCDBfTzn was measured in the same manner as in Example 1 and was found to be 116°C.

[0526] Although details are omitted, the structures (100) to (450) shown in Embodiment 1 can be produced in the same manner as in Examples 1 to 9. In this case, the structures can be produced by using the synthetic methods (a-1) to (a-5) or the method described in (b-1) using compounds (e.g., halides or boronic acids) having the substituents (R-01) to (R-112) shown in Embodiment 1 as appropriate.

[0527] In this example, a light-emitting device according to one embodiment of the present invention and a comparative light-emitting device described in the embodiment will be described. The structural formula of an organic compound used in the light-emitting device according to one embodiment of the present invention is shown below.

[0528]

[0529] (Method of Fabricating Light-Emitting Device 1) First, a film of indium tin oxide containing silicon oxide (ITSO) was formed on a glass substrate by sputtering to form a first electrode. The film thickness was 70 nm, and the electrode area was 2 mm × 2 mm.

[0530] Next, as a pretreatment for forming a light-emitting device on the substrate, the surface of the substrate was washed with water, baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0531] Then, 1 x 10 −４ The substrate was introduced into a vacuum deposition apparatus whose internal pressure had been reduced to about Pa, and was subjected to vacuum baking at 170° C. for 30 minutes in a heating chamber within the vacuum deposition apparatus, after which the substrate was allowed to cool for about 30 minutes.

[0532] Next, the substrate on which the first electrode was formed was fixed to a substrate holder provided in a vacuum evaporation apparatus so that the surface on which the first electrode was formed faced downward, and BBABnf represented by the above structural formula (i) and OCHD-003 were co-deposited on the first electrode by an evaporation method using resistance heating so that the weight ratio was 1:0.1 (=BBABnf:OCHD-003) and the film thickness was 10 nm to form a hole-injection layer. Here, OCHD-003 (also referred to as an electron-accepting substance) contained halogen and had a mass number of 672.

[0533] On the hole injection layer, BBABnf represented by the above structural formula (i) was vapor-deposited to a film thickness of 20 nm to form a first hole transport layer.

[0534] On the first hole transport layer, PCzN2 represented by the above structural formula (ii) was vapor deposited to a thickness of 10 nm to form a second hole transport layer.

[0535] On the second hole transport layer, an emitting layer was formed by co-depositing αN-βNPAnth (a material that functions as a host) represented by the above structural formula (iii) and 3,10PCA2Nbf(iv)-02 (a material that functions as a dopant) represented by the above structural formula (iv) in a weight ratio of 1:0.015 (=αN-βNPAnth:3,10PCA2Nbf(iv)-02) to a film thickness of 25 nm.

[0536] On the light-emitting layer, 6mBP-4Cz2PPm represented by the above structural formula (v) was vapor-deposited to a thickness of 10 nm to form a first electron transport layer.

[0537] A second electron-transport layer was formed on the first electron-transport layer by co-evaporation of Pn-mDBqPTzn (structural formula (100)) according to one embodiment of the present invention and Liq represented by the structural formula (vi) above at a weight ratio of 1:1 to a thickness of 15 nm.

[0538] On the second electron transport layer, Liq represented by the above structural formula (vi) was vapor-deposited to a thickness of 1 nm to form an electron injection layer.

[0539] Thereafter, a second electrode was formed on the electron injection layer by vapor-depositing aluminum to a film thickness of 200 nm, thereby completing the light-emitting device 1 of this example.

[0540] (Method of Fabricating Light-Emitting Device 2) Light-emitting device 2 uses mPn-mDMePyPTzn (structural formula (160)), which is one embodiment of the present invention, instead of Pn-mDBqPTzn in the second electron transport layer of light-emitting device 1 described above.

[0541] The element structures of the light-emitting devices 1 and 2 obtained as described above are shown in Table 1.

[0542]

[0543] These light-emitting devices were sealed with glass substrates in a nitrogen-atmosphere glove box to prevent exposure to the atmosphere (a sealant was applied around the device, and UV treatment and heat treatment at 80°C for 1 hour were performed during sealing), and then their initial characteristics were measured.

[0544] The emission spectra of the light-emitting devices 1 and 2 are shown in FIG. 21, their external quantum efficiency-luminance characteristics are shown in FIG. 22, and their current-voltage characteristics are shown in FIG.

[0545] Furthermore, the luminance of light emitting device 1 and light emitting device 2 is 1000 cd / m ２ The main characteristics around this range are shown in Table 2. A color luminance meter (BM-5A, manufactured by Topcon Corporation) was used to measure the luminance and CIE chromaticity, and a multichannel spectrometer (PMA-11, manufactured by Hamamatsu Photonics KK) was used to measure the emission spectrum. The measurements of each light-emitting device were carried out at room temperature (in an atmosphere maintained at 23°C).

[0546]

[0547] FIG. 21 shows that light emission originating from the blue fluorescent dopant 3,10PCA2Nbf(iv)-02 is obtained from the light-emitting device 1 and the light-emitting device 2 of one embodiment of the present invention.

[0548] Furthermore, FIG. 22 shows that the light-emitting devices 1 and 2 of one embodiment of the present invention have good external quantum efficiency.

[0549] Furthermore, it was found from FIG. 23 that the light-emitting device 1 and the light-emitting device 2 according to one embodiment of the present invention can be driven at a sufficiently low driving voltage.

[0550] 24 shows the results of the reliability test of the light-emitting devices 1 and 2. In the reliability test, the light-emitting devices 1 and 2 were tested at room temperature under a current of 50 mA / cm ２ The change in luminance with respect to the driving time of the element was measured under the condition of a constant current density of 100. In Fig. 24, the vertical axis represents normalized luminance (%) when the initial luminance is 100%, and the horizontal axis represents the driving time (h) of the element.

[0551] As shown in FIG. 24, it was found that the light-emitting devices 1 and 2, which are light-emitting devices according to one embodiment of the present invention, have long lifetimes.

[0552] The above-described device characteristics demonstrate that Pn-mDBqPTzn (structural formula (100)) and mPn-mDMePyPTzn (structural formula (160)) according to one embodiment of the present invention are materials with excellent electron transport properties, and are particularly suitable as materials for electron transport layers in light-emitting devices.

[0553] In this example, a reliability test of the light emitting device 1 and the light emitting device 2 at high temperatures will be described.

[0554] 25 shows the results of the reliability test at 85° C. for light-emitting device 1 and light-emitting device 2. Except for the temperature being set to 85° C., the conditions were the same as those for the reliability test at room temperature (FIG. 24).

[0555] 25 , in a reliability test at 85° C., it was found that the light-emitting device 1 had a longer life than the light-emitting device 2. In other words, it can be said that the Pn-mDBqPTzn (structural formula (100)) used in the light-emitting device 1 has better high-temperature resistance than the mPn-mDMePyPTzn (structural formula (160)) used in the light-emitting device 2.

[0556] One of the reasons why Pn-mDBqPTzn (structural formula (100)) has excellent high-temperature resistance is that it has a high glass transition temperature Tg of 161° C., as described above. On the other hand, mPn-mDMePyPTzn (structural formula (160)) has a Tg of 123° C.

[0557] One of the reasons why Pn-mDBqPTzn (structural formula (100)) has excellent high temperature resistance is that in general formula (G1), which is the molecular structure of the compound of the present invention, R ３ It can be said that a thin film with more stable film quality can be obtained by making the molecular weight of mPn-mDMePyPTzn used in light-emitting device 2 a pyridyl group and a molecular weight of 76 (excluding two methyl groups). On the other hand, Pn-mDBqPTzn used in light-emitting device 1 is a compound represented by the general formula (G1) ３ is dibenzo[f.h]quinoxaline, and the molecular weight of the substituent is 229. These differences are thought to have caused differences in the stability of the film quality and the high-temperature operating life of the fabricated devices.

[0558] For this reason, the glass transition temperature of the compound used in the light-emitting device should be 130° C. or higher, preferably 140° C. or higher, more preferably 150° C. or higher, and even more preferably 160° C. or higher.

[0559] Another factor is that Pn-mDBqPTzn has a larger number of fused rings than mPn-mDMePyPTzn. Another factor is that the molecular weight of the fused rings has increased. Another factor is that the number of nitrogen atoms contained in the fused rings has increased.

[0560] GD: circuit, IR: sub-pixel, M11: transistor, M12: transistor, M13: transistor, M14: transistor, M15: transistor, M16: transistor, M17: transistor, MS: wiring, PS: sub-pixel, REG: resist mask, RES: wiring, SE1: wiring, SE: distance, Si: single crystal, TX: wiring, VG: wiring, VS: wiring, 101: first electrode, 102: second electrode, 103: EL layer, 103a: EL layer, 103b: EL layer, 103B: EL layer, 103G: EL layer, 103R: EL layer, 103PS: light-receiving layer, 104B: hole injection / transport layer, 104G: hole injection / transport layer, 104R: hole injection / transport layer, 104PS: first transport layer, 105B: light emitting layer, 105G: light emitting layer, 105R: light emitting layer, 105PS: active layer, 106: charge generation layer, 106a: charge generation layer, 106b: charge generation layer, 107: insulating layer, 108B: electron transport layer, 108G: electron transport layer, 108R: electron transport layer, 108PS: second transport layer, 109: electron injection layer, 110B: sacrificial layer, 110G: sacrificial layer, 1...

Claims

1. A light-emitting device comprising an anode, a hole transport layer, a light-emitting layer, an electron transport layer having an azine compound, a cathode, and a partition wall, the electron transport layer has a region overlapping with the partition wall, A light-emitting device, wherein the glass transition temperature of the azine compound is greater than the glass transition temperature of the material of the hole transport layer and the glass transition temperature of the host material of the light-emitting layer.

2. A bendable light-emitting device comprising a flexible substrate, an anode, a hole transport layer, a light-emitting layer, an electron transport layer having an azine compound, a cathode, and a partition wall, the electron transport layer has a region overlapping with the partition wall, the electron transport layer has a region that overlaps a bent portion of the light-emitting device; A light-emitting device, wherein the glass transition temperature of the azine compound is greater than the glass transition temperature of the material of the hole transport layer and the glass transition temperature of the host material of the light-emitting layer.

3. A bendable light-emitting device comprising a flexible substrate, an anode, a hole transport layer, a light-emitting layer, an electron transport layer having an azine compound, a cathode, a capping layer, and a partition wall, the electron transport layer has a region overlapping with the partition wall, the electron transport layer has a region that overlaps a bent portion of the light-emitting device; the cap layer has an area that overlaps the bent portion of the light emitting device; the ordinary refractive index at a wavelength of 633 nm when the azine compound is formed into a thin film is smaller than the ordinary refractive index at a wavelength of 633 nm when the material contained in the capping layer is formed into a thin film and the ordinary refractive index at a wavelength of 633 nm when the host material of the light-emitting layer is formed into a thin film; A light-emitting device, wherein the glass transition temperature of the azine compound is greater than the glass transition temperature of the material of the hole transport layer and the glass transition temperature of the host material of the light-emitting layer.

4. A bendable light-emitting device comprising a flexible substrate, an anode, a hole transport layer, a light-emitting layer, an electron transport layer having an azine compound, a cathode, a capping layer, and a partition wall, the electron transport layer has a region overlapping with the partition wall, the electron transport layer has a region that overlaps a bent portion of the light-emitting device; the cap layer has an area that overlaps the bent portion of the light emitting device; the ordinary refractive index at a wavelength of 633 nm when the azine compound is formed into a thin film is smaller than the ordinary refractive index at a wavelength of 633 nm when the cap layer material is formed into a thin film and the ordinary refractive index at a wavelength of 633 nm when the host material of the light-emitting layer is formed into a thin film; the glass transition temperature of the azine compound is 120° C. or higher; A light-emitting device, wherein the glass transition temperature of the azine compound is greater than the glass transition temperature of the material of the hole transport layer and the glass transition temperature of the host material of the light-emitting layer.

5. In any one of claims 1 to 4, The azine compound is an organic compound represented by the following general formula (G1): 【Chemistry 1】 In General Formula (G1), R 1 to R 7 each independently represent any one of hydrogen (including deuterium), a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 1 to 60 carbon atoms, and a substituted or unsubstituted heteroaryl group having 1 to 60 carbon atoms. The aryl group or the heteroaryl group is any one of a phenyl group, a biphenyl group, a terphenyl group, a fluorenyl group, a spirobifluorenyl group, a naphthyl group, an anthracenyl group, a phenanthryl group, a fluoranthenyl group, a pyrenyl group, a chrysenyl group, a triphenylenyl group, a perylenyl group, an indenyl group, a benzoindenyl group, a pyrrolyl group, an indolyl group, a carbazolyl group, a furanyl group, a benzofuranyl group, a dibenzofuranyl group, a thiophenyl group, a benzothiophenyl group, a dibenzothiophenyl group, an imidazolyl group, a benzimidazolyl group, a triazolyl group, an oxazolyl group, an oxadiazolyl group, a thiazolyl group, a thiadiazolyl group, a pyrazolyl group, a pyridyl group, a pyrimidyl group, a pyridazyl group, a triazinyl group, a quinolinyl group, an indolocarbazolyl group, a benzocarbazolyl group, a quinoxalinyl group, and a dibenzoquinoxalinyl group. )

6. In claim 5, A light-emitting device wherein R3 is one of a phenanthryl group, a triphenylenyl group, a spirobifluorenyl group, a fluoranthenyl group, a carbazolyl group, or a dibenzoquinoxalinyl group.

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