Light-emitting device, light-emitting apparatus and electronic equipment

Abstract

To provide a novel light-emitting device excellent in convenience, utility, or reliability.SOLUTION: A light-emitting device comprises a first electrode, a second electrode, a unit, and a first layer. The second electrode has a region overlapping the first electrode. The unit has a region sandwiched between the first electrode and the second electrode. The unit has a second layer and a third layer. The second layer has a region which sandwiches the third layer between itself and the first electrode. The second layer contains a luminescent material. The first layer has a region sandwiched between the third layer and the first electrode. The first layer contains an acceptor-property material and a first material. The first layer has a first region and a second region. The first region has a region sandwiched between the second region and the first electrode. The first region contains an acceptor-property material at a first concentration. The second region contains an acceptor-property material at a second concentration. The second concentration is higher than zero and lower than the first concentration.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] One aspect of the present invention relates to a light-emitting device, a light-emitting apparatus, an electronic device, or a lighting device.

[0002] Note that one aspect of the present invention is not limited to the above technical field. The technical field of one aspect of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. Or, one aspect of the present invention relates to a process, a machine, a manufacture, or a composition of matter. Therefore, more specifically, examples of the technical field of one aspect of the present invention disclosed in this specification include semiconductor devices, display devices, light-emitting devices, power storage devices, storage devices, their driving methods, or their manufacturing methods.

Background Art

[0003] The practical application of light-emitting devices (organic EL elements) using electroluminescence (EL) of organic compounds has been progressing. The basic configuration of these light-emitting devices is such that an organic compound layer (EL layer) containing a light-emitting material is sandwiched between a pair of electrodes. By applying a voltage to this element to inject carriers and utilizing the recombination energy of the carriers, light emission from the light-emitting material can be obtained.

[0004] Since such light-emitting devices are self-emitting, they have higher visibility than liquid crystal displays and are suitable as pixels of displays. In addition, a display using such a light-emitting device has a great advantage in that it does not require a backlight and can be manufactured to be thin and lightweight. Furthermore, it is also characterized by a very fast response speed.

[0005] In addition, since these light-emitting devices can form a light-emitting layer continuously in two dimensions, light emission can be obtained in a planar shape. This is a characteristic that is difficult to obtain with point light sources typified by incandescent bulbs or LEDs, or line light sources typified by fluorescent lamps. Therefore, it also has high utility value as a planar light source that can be applied to lighting and the like.

[0006] Although display or lighting devices using such light-emitting devices are suitable for various electronic devices, research and development are being advanced to obtain light-emitting devices with better efficiency and longer lifespan.

[0007] The characteristics of light-emitting devices have improved remarkably, but it still has to be said that they are still insufficient to meet the high demands for all characteristics, including efficiency and durability. In particular, in order to solve problems such as burn-in, which is still an issue specific to EL, the smaller the decrease in efficiency due to deterioration, the better.

[0008] Patent Document 1 discloses a configuration in which a hole-transporting material having a HOMO level between the highest occupied molecular orbital (HOMO) level of the first hole injection layer and the HOMO level of the host material is provided between the first hole transport layer in contact with the hole injection layer and the light-emitting layer.

[0009] The characteristics of light-emitting devices have improved remarkably, but it still has to be said that they are still insufficient to meet the high demands for all characteristics, including efficiency or durability.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0011] One aspect of the present invention aims to provide a novel light-emitting device excellent in convenience, utility, or reliability. Or, one aspect of the present invention aims to provide a novel light-emitting apparatus excellent in convenience, utility, or reliability. Or, one aspect of the present invention aims to provide a novel electronic device excellent in convenience, utility, or reliability. Or, one aspect of the present invention aims to provide a novel lighting device excellent in convenience, utility, or reliability.

[0012] Note that the description of these problems does not prevent the existence of other problems. Note that one aspect of the present invention does not necessarily have to solve all of these problems. Note that other problems will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract these other problems from the description in the specification, drawings, claims, etc.

Means for Solving the Problems

[0013] (1) One aspect of the present invention is a light-emitting device having a first electrode, a second electrode, a unit, and a first layer.

[0014] The second electrode includes a region overlapping the first electrode, and the unit includes a region sandwiched between the first electrode and the second electrode.

[0015] The unit includes a second layer and a third layer. The second layer includes a region sandwiching the third layer between the second layer and the first electrode, and the second layer contains a light-emitting material EM.

[0016] The first layer includes a region sandwiched between the third layer and the first electrode, and the first layer contains an acceptor material AM and a first material HT1.

[0017] The first layer includes a first region and a second region.

[0018] The first region includes a region sandwiched between the second region and the first electrode, and the first region contains an acceptor material AM having a first concentration C1.

[0019] The second region contains a material AM having acceptor properties at a second concentration C2, and the second concentration C2 is higher than zero and lower than the first concentration C1.

[0020] Thereby, the driving voltage can be suppressed. Alternatively, the temperature dependence of the operating characteristics can be suppressed. As a result, a novel light-emitting device excellent in convenience, usefulness, or reliability can be provided.

[0021] (2) Further, one aspect of the present invention is the above-described light-emitting device in which the unit includes a fourth layer, and the fourth layer includes a region sandwiched between the second electrode and the second layer. The fourth layer contains a third material OMC, and the third material OMC is an organic complex of an alkali metal or an organic complex of an alkaline earth metal.

[0022] The third layer includes a third region and a fourth region, the fourth region includes a region sandwiched between the second layer and the third region, and the fourth region contains a second material HT2.

[0023] The first material HT1 has a first HOMO level, and the first HOMO level is -5.7 eV or more and -5.4 eV or less.

[0024] The second material HT2 has a second HOMO level, and the second HOMO level is in the range of -0.2 eV or more and 0 eV or less with respect to the first HOMO level.

[0025] (3) Further, one aspect of the present invention is the above-described light-emitting device in which the second layer contains a fourth material HOST, and the fourth material HOST has a first lowest unoccupied molecular orbital (LUMO) level.

[0026] The fourth layer includes a fifth region and a sixth region.

[0027] The fifth region includes a region sandwiched between the sixth region and the second layer, and the fifth region contains the fifth material ET. Also, the sixth region contains the third material OMC.

[0028] The fifth material ET has a second LUMO level, and the second LUMO level is in the range of -0.4 eV or more and -0.1 eV or less, preferably -0.4 eV or more and -0.15 eV or less, with respect to the first LUMO level.

[0029] (4) Also, one aspect of the present invention is the above-described light-emitting device in which the first region contains only the acceptor-type material AM.

[0030] (5) Also, one aspect of the present invention is the above-described light-emitting device in which the first region is in contact with the first electrode.

[0031] Thereby, it is possible to improve the reliability while suppressing an increase in the driving voltage. As a result, it is possible to provide a novel light-emitting device excellent in convenience, usefulness, or reliability.

[0032] (6) Also, one aspect of the present invention is a light-emitting device having the above-described light-emitting device and a transistor.

[0033] Thereby, it is possible to improve the reliability. Or, it is possible to improve the reliability while suppressing an increase in the driving voltage. As a result, it is possible to provide a novel light-emitting device excellent in convenience, usefulness, or reliability.

[0034] (7) Also, one aspect of the present invention is an electronic device having the above-described light-emitting device and a sensor, an operation button, a speaker, or a microphone.

[0035] Thereby, it is possible to improve the reliability. Or, it is possible to improve the reliability while suppressing an increase in the driving voltage. As a result, it is possible to provide a novel electronic device excellent in convenience, usefulness, or reliability.

[0036] In the drawings attached to this specification, components are classified by function and shown as blocks independent of each other in a block diagram. However, in reality, it is difficult to completely separate components by function, and one component may be related to multiple functions.

[0037] In this specification, the source and drain of a transistor change their names depending on the polarity of the transistor and the levels of the potentials applied to each terminal. Generally, in an n-channel type transistor, the terminal to which a low potential is applied is called the source, and the terminal to which a high potential is applied is called the drain. Also, in a p-channel type transistor, the terminal to which a low potential is applied is called the drain, and the terminal to which a high potential is applied is called the source. In this specification, for convenience, when explaining the connection relationship of transistors, it may be assumed that the source and drain are fixed, but in reality, the names of the source and drain are interchanged according to the above potential relationship.

[0038] In this specification, the source of a transistor means a source region that is part of a semiconductor film functioning as an active layer, or a source electrode connected to the semiconductor film. Similarly, the drain of a transistor means a drain region that is part of the semiconductor film, or a drain electrode connected to the semiconductor film. Also, the gate means a gate electrode.

[0039] In this specification, the state in which transistors are connected in series means, for example, a state in which only one of the source or drain of the first transistor is connected to only one of the source or drain of the second transistor. Also, the state in which transistors are connected in parallel means a state in which one of the source or drain of the first transistor is connected to one of the source or drain of the second transistor, and the other of the source or drain of the first transistor is connected to the other of the source or drain of the second transistor.

[0040] In this specification, "connection" means electrical connection, corresponding to a state where current, voltage, or potential can be supplied or transmitted. Therefore, the state of being connected does not necessarily refer to the state of direct connection, but also includes the state of being indirectly connected via circuit elements such as wiring, resistors, diodes, and transistors so that current, voltage, or potential can be supplied or transmitted.

[0041] Even if components that are independent on a circuit diagram are connected in this specification, in reality, for example, when a part of the wiring functions as an electrode, there may be a case where one conductive film has the functions of a plurality of components. In this specification, "connection" includes such a case where one conductive film has the functions of a plurality of components within its scope.

[0042] Also, in this specification, one of the first electrode or the second electrode of a transistor refers to the source electrode, and the other refers to the drain electrode.

Advantages of the Invention

[0043] According to one aspect of the present invention, a novel light-emitting device excellent in convenience, usefulness, or reliability can be provided. Or, a novel light-emitting device excellent in convenience, usefulness, or reliability can be provided. Or, a novel electronic device excellent in convenience, usefulness, or reliability can be provided. Or, a novel lighting device excellent in convenience, usefulness, or reliability can be provided.

[0044] Note that the description of these effects does not prevent the existence of other effects. Note that one aspect of the present invention does not necessarily have to have all of these effects. Note that other effects will naturally become apparent from the descriptions in the specification, drawings, claims, etc., and it is possible to extract these other effects from the descriptions in the specification, drawings, claims, etc.

Brief Description of the Drawings

[0045]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Figure 22

Figure 23

Figure 24

Figure 25

Figure 26

Figure 27

Figure 28

Figure 29

Figure 30

Figure 31

Figure 32

Figure 33

Figure 34

Figure 35

Figure 36

Figure 37

Figure 38

Figure 39

Figure 40

Figure 41

Figure 42

Figure 43

Figure 44

Figure 45

Figure 46

Figure 47

Figure 48

Figure 49

Figure 50

Figure 51

[0046] A light-emitting device according to one aspect of the present invention includes a first electrode, a second electrode, a unit, and a first layer. The second electrode has a region overlapping with the first electrode, the unit has a region sandwiched between the first electrode and the second electrode, and the unit includes a second layer and a third layer. The second layer has a region sandwiching the third layer between the second layer and the first electrode, and the second layer contains a light-emitting material. The first layer has a region sandwiched between the third layer and the first electrode. The first layer contains a material having acceptor properties and a first material, and the first layer includes a first region and a second region. The first region has a region sandwiched between the second region and the first electrode, the first region contains a material having acceptor properties at a first concentration, and the second region contains a material having acceptor properties at a second concentration. Note that the second concentration is higher than zero and lower than the first concentration.

[0047] As a result, the driving voltage can be suppressed. Alternatively, the temperature dependence of the operating characteristics can be suppressed. As a result, a novel light-emitting device excellent in convenience, usefulness, or reliability can be provided.

[0048] The embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and those skilled in the art can easily understand that the form and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention is not construed as being limited to the description of the embodiments shown below. In the configuration of the invention described below, the same parts or parts having the same function are commonly used with the same reference numerals among different drawings, and the repeated description thereof is omitted.

[0049] (Embodiment 1) In this embodiment, the configuration of the light-emitting device 150 according to one aspect of the present invention will be described with reference to FIG. 1.

[0050] <Configuration Example 1 of Light-Emitting Device 150> The light-emitting device 150 described in this embodiment has an electrode 101, an electrode 102, a unit 103, and a layer 104 (see FIG. 1A). Note that the electrode 102 has a region overlapping with the electrode 101.

[0051] 《Configuration Example 1 of Unit 103》 The unit 103 has a region sandwiched between the electrode 101 and the electrode 102, and the unit 103 includes a layer 111 and a layer 112. For example, the electrode 101 can be used as an anode and the electrode 102 can be used as a cathode.

[0052] For example, a layer selected from functional layers such as a hole transport layer, an electron transport layer, a carrier blocking layer, and an exciton blocking layer can be used for the unit 103.

[0053] 《Configuration Example 1 of Layer 111》 The layer 111 has a region sandwiching the layer 112 between itself and the electrode 101, and the layer 111 contains a light-emitting material EM.

[0054] Note that the layer 111 contains a host material. Also, the layer 111 can be referred to as a light-emitting layer. Preferably, the layer 111 is arranged in a region where holes and electrons recombine. Thereby, the energy generated by the recombination of carriers can be efficiently converted into light and emitted. Also, preferably, the layer 111 is arranged away from the metal used for the electrode or the like. Thereby, the quenching phenomenon caused by the metal used for the electrode or the like can be suppressed.

[0055] For example, a fluorescent substance, a phosphorescent substance, or a substance showing thermally activated delayed fluorescence (TADF) can be used as the light-emitting material. Thereby, the energy generated by the recombination of carriers can be emitted as light EL1 from the light-emitting material (see FIG. 1A).

[0056] [Fluorescent Substance] The fluorescent light-emitting substance can be used in layer 111. For example, the fluorescent light-emitting substances exemplified below can be used in layer 111. Note that the present invention is not limited thereto, and various known fluorescent light-emitting substances can be used in layer 111.

[0057] Specifically, 5,6-bis[4-(10-phenyl-9-anthryl)phenyl]-2,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-anthryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra(tert-butyl)perylene (abbreviation: TBP), 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), N,N''-(2-tert-butylanthracene-9,10-diyl-di-4,1-phenylene)bis[N,N',N'-triphenyl-1,4-phenylenediamine] (abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), N,N,N',N',N'',N'',N''',N''' - octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), coumarin 30, N-(9,10-diphenyl-2-anthryl)-N,9-Diphenyl-9H-carbazol-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(1,1'-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(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(1,1'-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(1,1'-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)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-mPhAFD), 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: BisDCJTM), N,N'-(pyrene-1,6-diyl)bis[(6,N-diphenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03), 3,10-bis[N-(9-phenyl-9H-carbazol-2-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10PCA2Nbf(IV)-02), 3,10-bis[N-(dibenzofuran-3-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10FrA2Nbf(IV)-02), etc. can be used.,

[0058] In particular, condensed aromatic diamine compounds typified by pyrene diamine compounds such as 1,6FLPAPrn, 1,6mMemFLPAPrn, and 1,6BnfAPrn-03 are preferred because they have high hole trapping properties and excellent luminescence efficiency or reliability.,

[0059] [Phosphorescent material 1] In addition, a phosphorescent material can be used for layer 111. For example, the phosphorescent materials exemplified below can be used for layer 111. Note that the present invention is not limited thereto, and various known phosphorescent materials can be used for layer 111.,

[0060] Specifically, an organometallic iridium complex having a 4H-triazole skeleton or the like can be used for layer 111. Specifically, tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN2]phenyl-κC}iridium(III) (abbreviation: [Ir(mpptz-dmp)3]), tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Mptz)3]), tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPrptz-3b)3]), etc. can be used.

[0061] Also, for example, an organometallic iridium complex having a 1H-triazole skeleton or the like can be used. Specifically, 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]), etc. can be used.

[0062] Also, for example, an organometallic iridium complex having an imidazole skeleton or the like can be used. Specifically, 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]), etc. can be used.

[0063] Also, for example, an organometallic iridium complex having a phenylpyridine derivative having an electron-withdrawing group as a ligand or the like can be used. Specifically, bis[2-(4’,6’-difluorophenyl)pyridinato-N,C 2’Iridium(III) tetrakis(1 - pyrazolyl)borate (abbreviation: FIr6), bis[2-(4’,6’-difluorophenyl)pyridinato-N,C 2’ Iridium(III) picolinate (abbreviation: FIr pic), bis{2-[3’,5’-bis(trifluoromethyl)phenyl]pyridinato-N,C 2’}Iridium(III) picolinate (abbreviation: [Ir(CF3ppy)2(pic)]), bis[2-(4’,6’-difluorophenyl)pyridinato-N,C 2’ Iridium(III) acetylacetonate (abbreviation: FIr acac), etc. can be used.

[0064] These are compounds that exhibit blue phosphorescent emission and are compounds having a peak in the emission wavelength from 440 nm to 520 nm.

[0065] [Phosphorescent substance 2] Also, for example, an organometallic iridium complex having a pyrimidine skeleton or the like can be used for layer 111. Specifically, 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-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm)2(acac)]), etc. can be used.

[0066] In addition, for example, an organometallic iridium complex having a pyrazine skeleton can be used. Specifically, (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-Me)2(acac)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-iPr)2(acac)]), etc. can be used.

[0067] In addition, for example, an organometallic iridium complex having a pyridine skeleton can be used. Specifically, tris(2-phenylpyridinato-N,C 2’ )iridium(III) (abbreviation: [Ir(ppy)3]), bis(2-phenylpyridinato-N,C 2’ )iridium(III) acetylacetonate (abbreviation: [Ir(ppy)2(acac)]), bis(benzo[h]quinolinato)iridium(III) acetylacetonate (abbreviation: [Ir(bzq)2(acac)]), tris(benzo[h]quinolinato)iridium(III) (abbreviation: [Ir(bzq)3]), tris(2-phenylquinolinato-N,C 2’ )iridium(III) (abbreviation: [Ir(pq)3]), bis(2-phenylquinolinato-N,C 2’ )iridium(III) acetylacetonate (abbreviation: [Ir(pq)2(acac)]), [2-d3-methyl-(2-pyridinyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(5-d3-methyl-2-pyridyl-κN2)phenyl-κ]iridium(III) (abbreviation: [Ir(5mppy-d3)2(mbfpypy-d3)]), [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)]), etc. can be used.

[0068] In addition, for example, rare earth metal complexes or the like can be used. Specifically, tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: [Tb(acac)3(Phen)]), etc. can be mentioned.

[0069] These are mainly compounds that exhibit green phosphorescent emission and have a peak in the emission wavelength range from 500 nm to 600 nm. In addition, an organometallic iridium complex having a pyrimidine skeleton is particularly preferable because it is also remarkably excellent in reliability or luminescence efficiency.

[0070] [Phosphorescent substance 3] In addition, for example, an organometallic iridium complex having a pyrimidine skeleton or the like can be used for layer 111. Specifically, (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(III) (abbreviation: [Ir(5mdppm)2(dibm)]), bis[4,6-bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(5mdppm)2(dpm)]), bis[4,6-di(naphthalen-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(d1npm)2(dpm)]), etc. can be used.

[0071] In addition, for example, an organometallic iridium complex having a pyrazine skeleton or the like can be used. Specifically, (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)]), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq)2(acac)]), etc. can be used.

[0072] In addition, for example, an organometallic iridium complex having a pyridine skeleton or the like can be used. Specifically, tris(1-phenylisoquinolinato-N,C2’ ) Iridium(III) (abbreviation: [Ir(piq)3]), bis(1-phenylisoquinolinato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(piq)2(acac)]), etc. can be used.

[0073] Also, for example, a platinum complex or the like can be used. Specifically, 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: PtOEP), etc. can be used.

[0074] Also, for example, a rare earth metal complex or the like can be used. Specifically, tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: [Eu(DBM)3(Phen)]), tris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviation: [Eu(TTA)3(Phen)]), etc. can be used.

[0075] These are compounds that exhibit red phosphorescent emission and have an emission peak at 600 nm to 700 nm. In addition, an organometallic iridium complex having a pyrazine skeleton can obtain red emission with a chromaticity that can be favorably used in a display device.

[0076] [Substance showing thermally activated delayed fluorescence (TADF)] A substance showing thermally activated delayed fluorescence (TADF) (also referred to as a TADF material) can be used for layer 111. For example, the TADF materials exemplified below can be used for layer 111. Note that the present invention is not limited thereto, and various known TADF materials can be used for layer 111.

[0077] For example, fullerenes and their derivatives, acridines and their derivatives, eosin derivatives, etc. can be used as TADF materials. Also, metal-containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (Pd), etc. can be used as TADF materials.

[0078] Specifically, protoporphyrin-tin fluoride complex (SnF2(Proto IX)), mesoporphyrin-tin fluoride complex (SnF2(Meso IX)), hematoporphyrin-tin fluoride complex (SnF2(Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (SnF2(Copro III-4Me)), octaethylporphyrin-tin fluoride complex (SnF2(OEP)), etioporphyrin-tin fluoride complex (SnF2(Etio I)), octaethylporphyrin-platinum chloride complex (PtCl2OEP), etc. with the structural formulas shown below can be used.

[0079]

Chemical formula

[0080] Also, for example, heterocyclic compounds having one or both of a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring can be used as TADF materials.

[0081] Specifically, 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ), 9-(4,6-diphenyl-1,3,5-triazin-2-yl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCCzTzn), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 2-[4-(10H-phenoxazin-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthen-9-one (abbreviation: ACRXTN), bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracene]-10'-one (abbreviation: ACRSA), etc. can be used.

[0082]

Chemical formula

[0083] Since the heterocyclic compound has a π-electron-excessive heterocyclic aromatic ring and a π-electron-deficient heterocyclic aromatic ring, it has both high electron transportability and hole transportability, which is preferable. Among them, among the skeletons having a π-electron-deficient heterocyclic aromatic ring, a pyridine skeleton, a diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), and a triazine skeleton are preferable because they are stable and have good reliability. In particular, a benzofuropyrimidine skeleton, a benzothienopyrimidine skeleton, a benzofuropyrazine skeleton, and a benzothienopyrazine skeleton are preferable because they have high acceptability and good reliability.

[0084] Among the skeletons having a π-electron-excessive heteroaromatic ring, an acridine skeleton, a phenoxazine skeleton, a phenothiazine skeleton, a furan skeleton, a thiophene skeleton, and a pyrrole skeleton are preferred because they are stable and have good reliability. Among them, a dibenzofuran skeleton is preferred as the furan skeleton, and a dibenzothiophene skeleton is preferred as the thiophene skeleton. Among the pyrrole skeletons, an indole skeleton, a carbazole skeleton, an indolocarbazole skeleton, a bicarbazole skeleton, and a 3-(9-phenyl-9H-carbazol-3-yl)-9H-carbazole skeleton are particularly preferred.

[0085] In addition, a substance in which a π-electron-excessive heteroaromatic ring and a π-electron-deficient heteroaromatic ring are directly bonded is particularly preferred because the electron-donating property of the π-electron-excessive heteroaromatic ring and the electron-accepting property of the π-electron-deficient heteroaromatic ring are both enhanced, and the energy difference between the S1 level and the T1 level becomes small, so that thermally activated delayed fluorescence can be efficiently obtained. Instead of the π-electron-deficient heteroaromatic ring, an aromatic ring bonded with an electron-withdrawing group such as a cyano group may be used. Further, as the π-electron-excessive skeleton, an aromatic amine skeleton, a phenazine skeleton, etc. can be used.

[0086] In addition, as the π-electron-deficient skeleton, a xanthene skeleton, a thioxanthene dioxide skeleton, an oxadiazole skeleton, a triazole skeleton, an imidazole skeleton, an anthraquinone skeleton, a boron-containing skeleton such as phenylborane or borantrene, an aromatic ring or heteroaromatic ring having a nitrile group or a cyano group such as benzonitrile or cyanobenzene, a carbonyl skeleton such as benzophenone, a phosphine oxide skeleton, a sulfone skeleton, etc. can be used.

[0087] Thus, a π-electron-deficient skeleton and a π-electron-excessive skeleton can be used instead of at least one of the π-electron-deficient heteroaromatic ring and the π-electron-excessive heteroaromatic ring.

[0088] Note that the TADF material is a material having a function capable of converting energy from triplet excitation energy to singlet excitation energy by reverse intersystem crossing with a small difference between the S1 level and the T1 level. Therefore, upconversion (reverse intersystem crossing) of triplet excitation energy to singlet excitation energy is possible with a small amount of thermal energy, and the singlet excited state can be efficiently generated. Further, the triplet excitation energy can be converted into light emission.

[0089] In addition, an exciplex (also referred to as an exciplex, exiplex or exciplex) that forms an excited state with two types of substances has a function as a TADF material in which the difference between the S1 level and the T1 level is extremely small and the triplet excitation energy can be converted into singlet excitation energy.

[0090] Note that as an index of the T1 level, a phosphorescence spectrum observed at a low temperature (for example, from 77K to 10K) may be used. As the TADF material, when a tangent is drawn at the trailing edge on the short wavelength side of the fluorescence spectrum, the energy of the wavelength of the extrapolated line is defined as the S1 level, and a tangent is drawn at the trailing edge on the short wavelength side of the phosphorescence spectrum, and the energy of the wavelength of the extrapolated line is defined as the T1 level, it is preferable that the difference between S1 and T1 is 0.3 eV or less, and more preferably 0.2 eV or less.

[0091] In addition, when the TADF material is used as a light-emitting substance, it is preferable that the S1 level of the host material is higher than the S1 level of the TADF material. Further, it is preferable that the T1 level of the host material is higher than the T1 level of the TADF material.

[0092] 《Configuration Example 1 of Layer 104》 Layer 104 includes a region sandwiched between layer 112 and electrode 101 (see Fig. 1A).

[0093] Layer 104 includes a material AM having acceptor properties and a material HT1. Note that a material including the material AM having acceptor properties and the material HT1 can be referred to as a composite material.

[0094] Material AM with acceptability For example, a compound having an electron-withdrawing group (halogen group or cyano group) can be used as the material with acceptability. Note that the organic compound with acceptability is easy to vaporize and form a film. Thereby, the productivity of the light-emitting device can be enhanced.

[0095] Specifically, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviation: F6-TCNNQ), 2-(7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyrene-2-ylidene) malononitrile, etc. can be used as the material with acceptability.

[0096] In particular, a compound in which an electron-withdrawing group is bonded to a condensed aromatic ring having a plurality of heteroatoms such as HAT-CN is thermally stable and preferable.

[0097] In addition, a [3]radialene derivative having an electron-withdrawing group (especially a halogen group such as a fluoro group or a cyano group) is preferable because of its very high electron-accepting property.

[0098] 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.

[0099] Material HT1 For example, a material having hole transporting properties can be used as the material HT1.

[0100] [Material having hole transporting properties] As the material having hole transporting properties, it preferably has a hole mobility of 1×10 -6 cm 2 / Vs or more. For example, a compound having an aromatic amine skeleton, a compound having a carbazole skeleton, a compound having a thiophene skeleton, a compound having a furan skeleton, etc. can be used.

[0101] Also, as the material having hole transporting properties, an amine compound or an organic compound having a π-electron excess type heteroaromatic ring skeleton is preferable. For example, a compound having an aromatic amine skeleton, a compound having a carbazole skeleton, a compound having a thiophene skeleton, a compound having a furan skeleton, etc. can be used.

[0102] Examples of the compound having an aromatic amine skeleton include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluorene-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluorene-2-amine (abbreviation: PCBASF), etc. can be used.

[0103] Examples of the compound having a carbazole skeleton include 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), 3,3'-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP), etc. can be used.

[0104] Examples of compounds having a thiophene skeleton include, for example, 4,4’,4’’-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV), etc., which can be used.

[0105] Examples of compounds having a furan skeleton include, for example, 4,4’,4’’-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II), etc., which can be used.

[0106] Among the above, compounds having an aromatic amine skeleton or a carbazole skeleton are preferable because they have good reliability, high hole transportability, and contribute to reducing the driving voltage.

[0107] <<Constitution Example 2 of Layer 104>> Layer 104 includes region 104A and region 104B. Region 104A includes a region sandwiched between region 104B and electrode 101, and region 104A contains a material AM having acceptor properties at a concentration C1. In other words, in layer 104, there is a distribution in the concentration of the material having acceptor properties.

[0108] Region 104B contains a material AM having acceptor properties at a concentration C2, and the concentration C2 is higher than zero and lower than the concentration C1.

[0109] Thereby, the driving voltage can be suppressed. Or, the temperature dependence of the operating characteristics can be suppressed. As a result, a novel light-emitting device excellent in convenience, usefulness, or reliability can be provided.

[0110] <<Constitution Example 2 of Light-Emitting Device 150>> In addition, in the light-emitting device 150 according to one aspect of the present invention, the unit 103 includes a layer 113 (see FIG. 1A).

[0111] <<Configuration Example 1 of Layer 113>> The layer 113 includes a region sandwiched between the electrode 102 and the layer 111, and the layer 113 contains a material OMC. The material OMC is an organic complex of an alkali metal or an organic complex of an alkaline earth metal.

[0112] A material containing an alkali metal, an alkali metal compound or an alkali metal complex and a substance having electron-transporting properties can be used as the electron-transporting material. In particular, when a substance having a relatively deep HOMO level of -5.7 eV or more and -5.4 eV or less is used for the composite material of the hole injection layer, the reliability of the light-emitting device can be improved. It is more preferable that the HOMO level of the electron-transporting material is -6.0 eV or more.

[0113] For example, it preferably contains an 8-hydroxyquinolinate structure. Specifically, 8-hydroxyquinolinate-lithium (abbreviation: Liq), 8-hydroxyquinolinate-sodium (abbreviation: Naq), etc. can be used.

[0114] In particular, a complex of a monovalent metal ion, especially a complex of lithium, is preferable, and Liq is more preferable. When an 8-hydroxyquinolinate structure is included, a methyl-substituted product thereof (for example, a 2-methyl-substituted product or a 5-methyl-substituted product) can also be used. Further, in the electron-transporting layer, it is preferable that there is a concentration difference (including the case where it is 0) in the thickness direction of the simple substance, compound or complex of an alkali metal or an alkaline earth metal.

[0115] <<Configuration Example 1 of Layer 112>> The layer 112 includes a region 112A and a region 112B. The region 112B includes a region sandwiched between the layer 111 and the region 112A, and the region 112B contains a material HT2.

[0116] <<Material HT2>> A material having hole transporting properties can be used for layer 112. For example, the material having hole transporting properties that can be used for layer 104 can be used for material HT2. Also, layer 112 can be referred to as a hole transport layer. Note that a substance having a band gap larger than the band gap of the luminescent material included in layer 111 is preferably used for region 112B. Thereby, energy transfer from the excitons generated in layer 111 to region 112B can be suppressed.

[0117] Note that material HT1 has a first HOMO level HOMO1, and the first HOMO level HOMO1 is -5.7 eV or more and -5.4 eV or less (see FIG. 1B). Also, material HT2 has a second HOMO level HOMO2, and the second HOMO level HOMO2 is in the range of -0.2 eV or more and 0 eV or less with respect to the first HOMO level HOMO1.

[0118] <Configuration Example 3 of Light Emitting Device 150> Also, in light emitting device 150 according to one aspect of the present invention, layer 111 includes a host material HOST, and the host material HOST has a first LUMO level LUMO1 (see FIG. 1B).

[0119] 《Host Material HOST》 A material having carrier transporting properties can be used for the host material HOST. For example, a material having hole transporting properties, a material having electron transporting properties, a TADF material, a material having an anthracene skeleton, a mixed material, etc. can be used for the host material.

[0120] [Material Having Hole Transporting Properties] For example, the material having hole transporting properties that can be used for layer 112 can be used for the host material HOST.

[0121] [Material Having Electron Transporting Properties] An organic compound having an anthracene skeleton can be used for the material having electron transporting properties. In particular, an organic compound containing both an anthracene skeleton and a heterocyclic skeleton can be preferably used.

[0122] For example, an organic compound containing both an anthracene skeleton and a nitrogen-containing 5-membered ring skeleton or an organic compound containing both an anthracene skeleton and a nitrogen-containing 6-membered ring skeleton can be used. Alternatively, an organic compound containing both a nitrogen-containing 5-membered ring skeleton containing two heteroatoms in the ring and an anthracene skeleton or an organic compound having a nitrogen-containing 6-membered ring skeleton containing two heteroatoms in the ring can be used. Specifically, a pyrazole ring, an imidazole ring, an oxazole ring, a thiazole ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, etc. can be preferably used for the heterocyclic skeleton.

[0123] In addition, as the material having electron transporting properties, a metal complex or an organic compound having a π-electron deficient heterocyclic aromatic ring skeleton is preferable. As the organic compound having a π-electron deficient heterocyclic aromatic ring skeleton, for example, a heterocyclic compound having a polyazole skeleton, a heterocyclic compound having a diazine skeleton, and a heterocyclic compound having a pyridine skeleton are preferable. In particular, a heterocyclic compound having a diazine skeleton or a heterocyclic compound having a pyridine skeleton has good reliability and is preferable. In addition, a heterocyclic compound having a diazine (pyrimidine or pyrazine) skeleton has high electron transporting properties and can reduce the driving voltage.

[0124] As the metal complex, for example, bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq2), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ), etc. can be used.

[0125] Examples of the heterocyclic compound having a polyazole skeleton include 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 2,2’,2’’-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), and the like.

[0126] Examples of the heterocyclic compound having a diazine skeleton include 2-[3-(dibenzothiophen-4-yl)phenyl]dibenz[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3’-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenz[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3’-(9H-carbazol-9-yl)biphenyl-3-yl]dibenz[f,h]quinoxaline (abbreviation: 2mCzBPDBq), 4,6-bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,8-bis[3-(dibenzothiophen-4-yl)phenyl]benzo[h]quinazoline (abbreviation: 4,8mDBtP2Bqn), and the like.

[0127] Examples of the heterocyclic compound having a pyridine skeleton include 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB), and the like.

[0128] [TADF material] The TADF material exemplified above can be used as a host material. When the TADF material is used as the host material, the triplet excitation energy generated by the TADF material is converted into singlet excitation energy by reverse intersystem crossing, and further, by transferring the energy to the luminescent material, the luminous efficiency of the light-emitting device can be enhanced. At this time, the TADF material functions as an energy donor, and the luminescent material functions as an energy acceptor.

[0129] This is very effective when the above luminescent material is a fluorescent luminescent material. Also, at this time, in order to obtain a high luminous efficiency, it is preferable that the S1 level of the TADF material is higher than the S1 level of the fluorescent luminescent material. Also, it is preferable that the T1 level of the TADF material is higher than the S1 level of the fluorescent luminescent material. Therefore, it is preferable that the T1 level of the TADF material is higher than the T1 level of the fluorescent luminescent material.

[0130] Also, it is preferable to use a TADF material that exhibits luminescence with a wavelength that overlaps with the wavelength of the absorption band on the lowest energy side of the fluorescent luminescent material. By doing so, the transfer of excitation energy from the TADF material to the fluorescent luminescent material becomes smooth, and luminescence can be obtained efficiently, which is preferable.

[0131] In addition, in order to efficiently generate singlet excitation energy from triplet excitation energy through reverse intersystem crossing, it is preferable that carrier recombination occurs in the TADF material. Further, it is preferable that the triplet excitation energy generated in the TADF material does not transfer to the triplet excitation energy of the fluorescent substance. For this purpose, it is preferable that the fluorescent substance has a protecting group around the lumophore (skeleton responsible for luminescence) of the fluorescent substance. As the protecting group, a substituent having no π bond is preferable, a saturated hydrocarbon is preferable, and specifically, an alkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, and a trialkylsilyl group having 3 to 10 carbon atoms can be mentioned. It is more preferable that there are a plurality of protecting groups. Since a substituent having no π bond has poor function of transporting carriers, it is possible to increase the distance between the TADF material and the lumophore of the fluorescent substance with little influence on carrier transport or carrier recombination.

[0132] Here, the lumophore refers to an atomic group (skeleton) that causes luminescence in the fluorescent substance. The lumophore preferably has a skeleton having a π bond, preferably contains an aromatic ring, and preferably has a condensed aromatic ring or a condensed heteroaromatic ring.

[0133] Examples of the condensed aromatic ring or the condensed heteroaromatic ring include a phenanthrene skeleton, a stilbene skeleton, an acridone skeleton, a phenoxazine skeleton, and a phenothiazine skeleton. In particular, fluorescent substances having a naphthalene skeleton, an anthracene skeleton, a fluorene skeleton, a chrysene skeleton, a triphenylene skeleton, a tetracene skeleton, a pyrene skeleton, a perylene skeleton, a coumarin skeleton, a quinacridone skeleton, and a naphthobisbenzofuran skeleton are preferable because of their high fluorescence quantum yields.

[0134] [Material having an anthracene skeleton] When a fluorescent substance is used as the luminescent substance, a material having an anthracene skeleton is suitable as the host material. When a substance having an anthracene skeleton is used as the host material of the fluorescent substance, it is possible to realize a light-emitting layer with good luminous efficiency and durability.

[0135] As the substance having an anthracene skeleton used as the host material, a substance having a diphenylanthracene skeleton, particularly a substance having a 9,10-diphenylanthracene skeleton, is preferable because it is chemically stable. Further, when the host material has a carbazole skeleton, it is preferable because the hole injection and transport properties are enhanced. However, when the host material contains a benzocarbazole skeleton in which a benzene ring is further condensed with carbazole, the HOMO is about 0.1 eV shallower than that of carbazole, and holes can easily enter, so it is more preferable.

[0136] In particular, when the host material contains a dibenzocarbazole skeleton, the HOMO is about 0.1 eV shallower than that of carbazole, making it easier for holes to enter. In addition, it has excellent hole transport properties and high heat resistance, so it is suitable. Therefore, a substance having both a 9,10-diphenylanthracene skeleton and a carbazole skeleton (or a benzocarbazole skeleton or a dibenzocarbazole skeleton) is more preferable as the host material. From the above viewpoints of hole injection and transport properties, a benzofluorene skeleton or a dibenzofluorene skeleton may be used instead of the carbazole skeleton.

[0137] Examples of the substance having an anthracene skeleton include 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 9-[4-(10-phenyl-9-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]-benzo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl-10-{4-(9-phenyl-9H-fluoren-9-yl)biphenyl-4'-yl}anthracene (abbreviation: FLPPA), 9-(1-naphthyl)-10-[4-(2-naphthyl)phenyl]anthracene (abbreviation: αN-βNPAnth), etc. can be used.

[0138] In particular, CzPA, cgDBCzPA, 2mBnfPPA, and PCzPA exhibit very good properties.

[0139] [Constitution Example 1 of Mixed Material] Furthermore, a material obtained by mixing a plurality of substances can be used as the host material. For example, a material obtained by mixing a material having electron transporting properties and a material having hole transporting properties can be suitably used as the host material. By mixing a material having electron transporting properties and a material having hole transporting properties, the carrier transporting property of layer 111 can be easily adjusted. In addition, the control of the recombination region can also be easily performed. The weight ratio of the material having hole transporting properties to the material having electron transporting properties contained in the mixed material may be Hole transporting material: Electron transporting material = 1:19 to 19:1.

[0140] [Constitution Example 2 of Mixed Material] In addition, a material mixed with a phosphorescent substance can be used as the host material. The phosphorescent substance can be used as an energy donor that supplies excitation energy to the fluorescent substance when the fluorescent substance is used as the luminescent substance.

[0141] In addition, a mixed material containing a material that forms an exciplex can be used as the host material. For example, a material in which the emission spectrum of the formed exciplex overlaps with the wavelength of the absorption band on the lowest energy side of the luminescent substance can be used as the host material. Thereby, energy transfer becomes smooth and the emission efficiency can be improved. Or, the driving voltage can be suppressed.

[0142] Note that at least one of the materials that form the exciplex may be a phosphorescent substance. By doing so, the triplet excitation energy can be efficiently converted into singlet excitation energy by reverse intersystem crossing.

[0143] As a combination of materials that efficiently form an exciplex, it is preferable that the HOMO level of the hole-transporting material is equal to or higher than the HOMO level of the electron-transporting material. Also, it is preferable that the LUMO level of the hole-transporting material is equal to or higher than the LUMO level of the electron-transporting material. Note that the LUMO level and HOMO level of the material can be derived from the electrochemical properties (reduction potential and oxidation potential) of the material measured by cyclic voltammetry (CV) measurement.

[0144] Note that the formation of the exciplex can be confirmed, for example, by comparing the emission spectrum of the hole-transporting material, the emission spectrum of the electron-transporting material, and the emission spectrum of a mixed film obtained by mixing these materials, and observing the phenomenon that the emission spectrum of the mixed film shifts to a longer wavelength (or has a new peak on the longer wavelength side) than the emission spectra of the individual materials. Alternatively, the formation of the exciplex can be confirmed by comparing the transient photoluminescence (PL) of the hole-transporting material, the transient PL of the electron-transporting material, and the transient PL of a mixed film obtained by mixing these materials, and observing differences in transient responses such as the transient PL lifetime of the mixed film having a longer-lived component or a larger proportion of a delayed component than the transient PL lifetimes of the individual materials. Also, the above-mentioned transient PL may be read as transient electroluminescence (EL). That is, the formation of the exciplex can also be confirmed by comparing the transient EL of the hole-transporting material, the transient EL of the electron-transporting material, and the transient EL of a mixed film of these materials, and observing differences in transient responses.

[0145] 《Configuration Example 2 of Unit 103》 Also, Unit 103 includes layer 113 (see Fig. 1A).

[0146] 《Configuration Example 2 of Layer 113》 For example, a material having electron transporting properties can be used for layer 113. Further, layer 113 can be referred to as an electron transport layer. Note that a configuration in which a substance having a band gap larger than the band gap of the luminescent material contained in layer 111 is used for layer 113 is preferable. Thereby, energy transfer from excitons generated in layer 111 to layer 113 can be suppressed.

[0147] [Material having electron transporting properties] As the material having electron transporting properties, the electron mobility at the square root of the electric field strength [V / cm] of 600 is 1×10 -7 cm 2 / Vs or more and 5×10 -5 cm 2 / Vs or less is preferable. By suppressing the electron transporting property in the electron transport layer, the amount of electrons injected into the light emitting layer can be controlled. Or, it is possible to prevent the light emitting layer from being in a state of excessive electrons.

[0148] For example, a material having electron transporting properties that can be used for layer 111 can be used for layer 113. Specifically, a material having electron transporting properties that can be used for a host material can be used for layer 113.

[0149] 《Configuration Example 3 of Layer 113》 Layer 113 includes region 113A and region 113B. Region 113A includes a region sandwiched between region 113B and layer 111, and region 113A contains material ET. Note that region 113B contains material OMC.

[0150] Material ET has a second LUMO level LUMO2, and the second LUMO level LUMO2 is in the range of -0.4 eV or more and -0.1 eV or less, preferably -0.4 eV or more and -0.15 eV or less with respect to the first LUMO level LUMO1 (see FIG. 1B).

[0151] 《Configuration Example 3 of Layer 104》 Further, in one aspect of the present invention, region 104A is in contact with electrode 101.

[0152] This makes it easier to inject holes from the electrode 101 into the region 104A. Alternatively, the reliability can be improved while suppressing the driving voltage. As a result, a novel light-emitting device excellent in convenience, usefulness, or reliability can be provided.

[0153] <<Configuration Example of Electrode 101>> For example, a conductive material can be used for the electrode 101. Specifically, metals, alloys, conductive compounds, and mixtures thereof can be used for the electrode 101. For example, a material having a work function of 4.0 eV or more can be preferably used.

[0154] For example, indium tin oxide (ITO), indium tin oxide containing silicon or silicon oxide, indium zinc oxide, tungsten oxide, indium oxide containing zinc oxide (IWZO), etc. can be used.

[0155] Also, for example, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), or nitrides of metal materials (for example, titanium nitride), etc. can be used. Or, graphene can be used.

[0156] <<Configuration Example of Electrode 102>> For example, a conductive material can be used for the electrode 102. Specifically, metals, alloys, electrically conductive compounds, and mixtures thereof can be used for the electrode 102. For example, a material having a smaller work function than that of the electrode 101 can be used for the electrode 102. Specifically, a material having a work function of 3.8 eV or less can be preferably used.

[0157] For example, elements belonging to Group 1 of the periodic table, elements belonging to Group 2 of the periodic table, rare earth metals, and alloys containing these can be used for the electrode 102.

[0158] Specifically, lithium (Li), cesium (Cs), etc., magnesium (Mg), calcium (Ca), strontium (Sr), etc., europium (Eu), ytterbium (Yb), etc., and alloys containing these (MgAg, AlLi) can be used for the electrode 102.

[0159] 《Configuration Example of Layer 105》 The light-emitting device 150 described in this embodiment has a layer 105. The layer 105 includes a region sandwiched between the electrode 102 and the unit 103.

[0160] For example, a material having electron-injecting properties can be used for the layer 105. Specifically, a substance having donor properties can be used for the layer 105. Alternatively, a composite material in which a substance having donor properties is contained in a material having electron-transporting properties can be used for the layer 105. Thereby, for example, it is possible to facilitate the injection of electrons from the electrode 102. Alternatively, the driving voltage of the light-emitting device can be reduced. Alternatively, various conductive materials can be used for the electrode 102 regardless of the work function. Specifically, Al, Ag, ITO, indium tin oxide containing silicon or silicon oxide, etc. can be used for the electrode 102.

[0161] [Material 1 with Electron-Injecting Properties] For example, an alkali metal, an alkaline earth metal, a rare earth metal, or a compound thereof can be used as the substance having donor properties. Alternatively, an organic compound such as tetrathianaphthacene (abbreviation: TTN), nickelocene, decamethylnickelocene, etc. can also be used as the substance having donor properties.

[0162] Specifically, an alkali metal compound (including oxides, halides, carbonates), an alkaline earth metal compound (including oxides, halides, carbonates), or a compound of a rare earth metal (including oxides, halides, carbonates), etc. can be used for the material having electron-injecting properties.

[0163] Specifically, lithium oxide, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), lithium carbonate, cesium carbonate, lithium 8-hydroxyquinolinate (abbreviation: Liq), etc. can be used for materials having electron injection properties.

[0164] [Material 2 with electron injection properties] For example, a composite material containing an alkali metal or an alkaline earth metal or their compounds and a substance having electron transport properties can be used for materials having electron injection properties.

[0165] For example, a material having electron transport properties that can be used for unit 103 can be used for materials having electron injection properties.

[0166] Also, a material containing a fluoride of an alkali metal in a microcrystalline state and a substance having electron transport properties or a material containing a fluoride of an alkaline earth metal in a microcrystalline state and a substance having electron transport properties can be used for materials having electron injection properties.

[0167] In particular, a material containing 50 wt% or more of a fluoride of an alkali metal or a fluoride of an alkaline earth metal can be preferably used. Or, an organic compound having a bipyridine skeleton can be preferably used. Thereby, the refractive index of layer 105 can be reduced. Or, the external quantum efficiency of the light-emitting device can be improved.

[0168] [Material 3 with electron injection properties] Also, electride can be used for materials having electron injection properties. For example, a substance obtained by adding electrons at a high concentration to a mixed oxide of calcium and aluminum, etc. can be used for materials having electron injection properties.

[0169] Note that this embodiment can be appropriately combined with other embodiments shown in this specification.

[0170] (Embodiment 2) In this embodiment, the configuration of the light-emitting device 150 according to one aspect of the present invention will be described with reference to FIG. 2A.

[0171] FIG. 2A is a cross-sectional view for explaining the configuration of a light-emitting device according to one aspect of the present invention, which has a configuration different from the configuration shown in FIG. 1.

[0172] <Configuration example of the light-emitting device 150> The light-emitting device 150 described in this embodiment includes an electrode 101, an electrode 102, a unit 103, an intermediate layer 106, and a unit 103(12) (see FIG. 2A). Further, a layer 104(12) and a layer 105(12) can be used.

[0173] Note that a configuration similar to the layer 104 described in Embodiment 1 can be used for the layer 104(12), and a configuration similar to the layer 105 described in Embodiment 1 can be used for the layer 105(12).

[0174] The unit 103 includes a region sandwiched between the electrode 101 and the electrode 102, the unit 103(12) includes a region sandwiched between the electrode 101 and the unit 103, and the intermediate layer 106 includes a region sandwiched between the unit 103(12) and the unit 103. Further, the layer 105(12) includes a region sandwiched between the unit 103(12) and the intermediate layer 106.

[0175] The light-emitting device 150 has a plurality of stacked units. Note that the number of the plurality of stacked units is not limited to 2, and three or more units can be stacked. Note that a configuration including the intermediate layer 106 and the plurality of units may be referred to as a stacked light-emitting device or a tandem light-emitting device. Thereby, high-brightness light emission can be enabled while keeping the current density low. Or the reliability can be improved. Or the driving voltage can be reduced as compared with the same brightness. Or the power consumption can be suppressed.

[0176] <<Configuration example of the unit 103(12)>> The configuration that can be used for unit 103 can be used for unit 103(12). For example, the same configuration as unit 103 can be used for unit 103(12).

[0177] Alternatively, a configuration different from unit 103 can be used for unit 103(12). For example, a configuration with a light emission color different from that of unit 103 can be used for unit 103(12). Specifically, unit 103 that emits red light and green light and unit 103(12) that emits blue light can be used. Thereby, a light emitting device that emits light of a desired color can be provided. Or, for example, a light emitting device that emits white light can be provided.

[0178] 《Configuration example of intermediate layer 106》 The intermediate layer 106 includes layer 104 and layer 106A. The intermediate layer 106 has a function of supplying electrons to one of unit 103 and unit 103(12) and supplying holes to the other.

[0179] Layer 104 includes an acceptor material AM and material HT1, and layer 104 includes region 104A and region 104B. Also, region 104A is a region sandwiched between region 104B and electrode 101, and region 104A contains acceptor material AM having a concentration C1.

[0180] Region 104B contains acceptor material AM having a concentration C2, and concentration C2 is higher than zero and lower than concentration C1.

[0181] Thereby, the driving voltage can be suppressed. Or, the temperature dependence of the operating characteristics can be suppressed. As a result, a novel light emitting device excellent in convenience, usefulness or reliability can be provided.

[0182] Incidentally, layer 104 can be referred to as a charge generation layer. The charge generation layer has a function of supplying electrons to the anode side and holes to the cathode side by applying a voltage. Specifically, it can supply electrons to unit 103(12) disposed on the anode side.

[0183] 《Configuration Example of Layer 106A》 Layer 106A includes a region sandwiched between layer 104 and unit 103(12). Incidentally, layer 106A can be referred to as, for example, an electron relay layer.

[0184] For example, a substance having electron transporting properties can be used for the electron relay layer. Thereby, the layer in contact with the anode side of the electron relay layer can be separated from the layer in contact with the cathode side of the electron relay layer. Or, the interaction between the layer in contact with the anode side of the electron relay layer and the layer in contact with the cathode side of the electron relay layer can be reduced. Or, electrons can be smoothly supplied to the layer in contact with the anode side of the electron relay layer.

[0185] For example, a substance having electron transporting properties can be preferably used for the electron relay layer. Specifically, a substance having a LUMO level can be preferably used for the electron relay layer between the LUMO level of acceptor material AM having acceptor properties used for layer 104 and the LUMO level of hole transporting material HT1 having hole transporting properties used for layer 104.

[0186] For example, a substance having electron transporting properties and having a LUMO level in the range of -5.0 eV or more, preferably -5.0 eV or more and -3.0 eV or less can be used for the electron relay layer.

[0187] Specifically, a phthalocyanine-based material can be used for the electron relay layer. Or, a metal complex having a metal-oxygen bond and an aromatic ligand can be used for the electron relay layer.

[0188] Incidentally, this embodiment can be appropriately combined with other embodiments shown in this specification.

[0189] (Embodiment 3) In this embodiment, the configuration of the light-emitting device 150 according to one aspect of the present invention will be described with reference to FIG. 2B.

[0190] FIG. 2B is a cross-sectional view for explaining the configuration of a light-emitting device according to one aspect of the present invention, which has a configuration different from the configuration shown in FIG. 1.

[0191] <Configuration example of the light-emitting device 150> Further, the light-emitting device 150 described in this embodiment has an electrode 101, an electrode 102, a unit 103, a layer 104, and an intermediate layer 106 (see FIG. 2B).

[0192] Note that the light-emitting device 150 is different from the configuration shown in FIG. 1 in that it has an intermediate layer 106 between the layer 105 and the electrode 102. Here, the different parts will be described in detail, and for the parts where the same configuration can be used, the above description will be incorporated by reference.

[0193] 《Configuration example of the intermediate layer 106》 The intermediate layer 106 includes a region sandwiched between the unit 103 and the electrode 102, and the intermediate layer 106 includes a layer 106A and a layer 106B.

[0194] 《Configuration example of the layer 106A》 The layer 106A includes a region sandwiched between the layer 106B and the layer 105. For example, the electron relay layer described in Embodiment 2 can be used as the layer 106A.

[0195] 《Configuration example of the layer 106B》 The layer 106B can be referred to as a charge generation layer, for example. The charge generation layer has a function of supplying electrons to the anode side and holes to the cathode side by applying a voltage. Specifically, it can supply electrons to the unit 103 disposed on the anode side.

[0196] Further, for example, a composite material exemplified as a material having hole injection properties can be used for the charge generation layer. Further, for example, a laminated film in which a film containing the composite material and a film containing a material having hole transport properties are laminated can be used for the charge generation layer.

[0197] <Method for manufacturing the light emitting device 150> For example, each layer of the electrode 101, the electrode 102, the unit 103, and the intermediate layer 106 can be formed by using a dry method, a wet method, a vapor deposition method, a droplet discharge method, a coating method, a printing method, or the like. Further, each layer of the unit 103(12) can also be formed by using a similar method. Further, different methods can be used for forming each component.

[0198] Specifically, the light emitting device 150 can be manufactured by using a vacuum vapor deposition apparatus, an inkjet apparatus, a coating apparatus such as a spin coater, a gravure printing apparatus, an offset printing apparatus, a screen printing apparatus, or the like.

[0199] For example, an electrode can be formed by using a wet method using a paste of a metal material or a sol-gel method. Specifically, an indium oxide-zinc oxide film can be formed by a sputtering method using a target in which 1 to 20 wt% of zinc oxide is added to indium oxide. Further, an indium oxide (IWZO) film containing tungsten oxide and zinc oxide can be formed by a sputtering method using a target containing 0.5 to 5 wt% of tungsten oxide and 0.1 to 1 wt% of zinc oxide with respect to indium oxide.

[0200] Note that the present embodiment can be appropriately combined with other embodiments shown in this specification.

[0201] (Embodiment 4) In this embodiment, the configuration of the light emitting panel 700 according to one aspect of the present invention will be described with reference to FIG. 3.

[0202] <Configuration example of the light emitting panel 700> The light-emitting panel 700 described in this embodiment has a light-emitting device 150 and a light-emitting device 150(2) (Fig. 3).

[0203] For example, the light-emitting device described in any one of Embodiments 1 to 3 can be used as the light-emitting device 150.

[0204] <Configuration Example of Light-Emitting Device 150(2)> The light-emitting device 150(2) described in this embodiment has an electrode 101(2), an electrode 102, and a unit 103(2) (see Fig. 3). For example, a part of the configuration of the light-emitting device 150 can be used as a part of the configuration of the light-emitting device 150(2). Thereby, a part of the configuration can be made common. Or, the manufacturing process can be simplified.

[0205] 《Configuration Example of Unit 103(2)》 The unit 103(2) includes a region sandwiched between the electrode 101(2) and the electrode 102. The unit 103(2) also includes a layer 111(2). For example, a light-emitting material that emits light of a color different from that of the layer 111 included in the unit 103 can be used for the layer 111(2).

[0206] The unit 103(2) has a single-layer structure or a laminated structure. For example, a layer selected from functional layers such as a hole transport layer, an electron transport layer, a carrier blocking layer, and an exciton blocking layer can be used for the unit 103(2).

[0207] The unit 103(2) includes a region where electrons injected from one electrode recombine with holes injected from the other electrode. For example, it includes a region where holes injected from the electrode 101(2) recombine with electrons injected from the electrode 102.

[0208] 《Configuration Example of Layer 104(2)》 Layer 104(2) includes a region sandwiched between the electrode 101 and the unit 103. Note that layer 104(2) can be referred to as a hole injection layer. For example, a material having hole injection properties can be used for layer 104(2).

[0209] Specifically, an acceptor material and a composite material can be used for layer 104(2). Note that an organic compound and an inorganic compound can be used for the acceptor material. By applying an electric field, the acceptor material can extract electrons from an adjacent hole transport layer (or hole transport material).

[0210] [Example 1 of a material having hole injection properties] An acceptor material can be used for the material having hole injection properties. Thereby, for example, holes can be easily injected from the electrode 101. Or, the driving voltage of the light-emitting device can be reduced.

[0211] For example, the acceptor material described in Embodiment 1 can be used for the material having hole injection properties.

[0212] In addition, molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, manganese oxide, etc. can be used for the acceptor material.

[0213] In addition, phthalocyanine-based complex compounds such as phthalocyanine (abbreviation: H2Pc) or copper phthalocyanine (CuPc), and compounds having an aromatic amine skeleton such as 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (abbreviation: DNTPD) can be used.

[0214] In addition, polymers such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS) can be used.

[0215] [Example 2 of material having hole injection property] The composite material can be used for the material having hole injection property. For example, a composite material in which a material having acceptor property is contained in a material having hole transporting property can be used. Thereby, the material for forming the electrode can be selected in a wide range regardless of the work function. Or, not only the material having a large work function but also the material having a small work function can be used for the electrode 101.

[0216] Various organic compounds can be used for the material having hole transporting property of the composite material. For example, a compound having an aromatic amine skeleton, a carbazole derivative, an aromatic hydrocarbon, a polymer compound (oligomer, dendrimer, polymer, etc.) can be used for the material having hole transporting property of the composite material. Note that a substance having a hole mobility of 1×10 -6 cm 2 / Vs or more can be preferably used.

[0217] In addition, for example, a substance having a relatively deep HOMO level with a HOMO level of -5.7 eV or more and -5.4 eV or less can be preferably used for the material having hole transporting property of the composite material. Thereby, the injection of holes into the hole transporting layer can be facilitated. Or, the reliability of the light emitting device can be improved.

[0218] Examples of the compound having an aromatic amine skeleton include N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), etc.

[0219] Examples of the carbazole derivative include 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA), 1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene, etc.

[0220] Examples of aromatic hydrocarbons include, for example, 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA), 2-tert-butyl-9,10-bis[2-(1-naphthyl)phenyl]anthracene, 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene, 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene, 9,9’-bianthryl, 10,10’-diphenyl-9,9’-bianthryl, 10,10’-bis(2-phenylphenyl)-9,9’-bianthryl, 10,10’-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9’-bianthryl, anthracene, tetracene, rubrene, perylene, 2,5,8,11-tetra(tert-butyl)perylene, etc. can be used.

[0221] Examples of aromatic hydrocarbons having a vinyl group include, for example, 4,4’-bis(2,2-diphenylvinyl)biphenyl (abbreviation: DPVBi), 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviation: DPVPA), etc. can be used.

[0222] For example, pentacene, coronene, etc. can also be used.

[0223] As the high molecular compound, for example, 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), poly[N,N’-bis(4-butylphenyl)-N,N’-bis(phenyl)benzidine] (abbreviation: Poly-TPD), etc. can be used.

[0224] Also, for example, a substance having any one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton can be suitably used as a material having hole transporting properties of the composite material. Further, an aromatic amine having a substituent containing a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine having a naphthalene ring, or a substance comprising an aromatic monoamine in which a 9-fluorenyl group is bonded to the nitrogen of the amine via an arylene group can be used. In addition, when a substance having an N,N-bis(4-biphenyl)amino group is used, the reliability of the light emitting device can be improved.

[0225] Examples of materials having hole-transporting properties among these composite materials include N-(4-biphenyl)-6,N-diphenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf), 4,4'-bis(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)-4''-phenyltriphenylamine (abbreviation: BnfBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf(8)), N,N-bis(4-biphenyl)benzo[b]naphtho[2,3-d]furan-4-amine (abbreviation: BBABnf(II)(4)), N,N-bis[4-(dibenzofuran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB1TP), N-[4-(dibenzothiophene-4-yl)phenyl]-N-phenyl-4-biphenylamine (abbreviation: ThBA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenylamine (abbreviation: BBAβNB), 4-[4-(2-naphthyl)phenyl]-4',4''-diphenyltriphenylamine (abbreviation: BBAβNBi), 4,4'-diphenyl-4''-(6;1'-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)naphthyl-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4,4'-diphenyl-4''-(6;2'-binaphthyl-2-yl)triphenylamine (abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-(7;2'-binaphthyl-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diphenyl-4''-(4;2'-binaphthyl-1-yl)triphenylamine (abbreviation: BBAβNαNB), 4,4'-Diphenyl-4''-(5;2'-binaphthalen-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 (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(1,1'-biphenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-diphenyl-4'-(2-naphthyl)-4''-{9-(4-biphenylyl)carbazole}triphenylamine (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(4-biphenylyl)-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: BBASF), N,N-bis(1,1'-biphenyl-4-yl)-9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: BBASF(4)), N-(1,1'-biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluorene-2-yl)-9,9'-spirobi(9H-fluorene)-4-amine (abbreviation: oFBiSF), N-(4-biphenyl)-N-(dibenzofuran-4-yl)-9,9-Dimethyl-9H-fluorene-2-amine (abbreviation: FrBiF), N-[4-(1-naphthyl)phenyl]-N-[3-(6-phenyldibenzofuran-4-yl)phenyl]-1-naphthylamine (abbreviation: mPDBfBNBN), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluorene-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-[4-(9-phenylfluorene-9-yl)phenyl]triphenylamine (abbreviation: BPAFLBi), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluorene-2-amine (abbreviation: PCBASF), N-(1,1'-biphenyl-4-yl)-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluorene-2-amine (abbreviation: PCBBiF), N,N-bis(9,9-dimethyl-9H-fluorene-2-yl)-9,9'-spirobi-9H-fluorene-4-amine, N,N-bis(9,9-dimethyl-9H-fluorene-2-yl)-9,9'-spirobi-9H-fluorene-3-amine, N,N-bis(9,9-dimethyl-9H-fluorene-2-yl)-9,9'-spirobi-9H-fluorene-2-amine, N,N-bis(9,9-dimethyl-9H-fluorene-2-yl)-9,9'-spirobi-9H-fluorene-1-amine, etc. can be used.,

[0226] [Example 3 of materials having hole injection properties] A composite material containing a material having hole transporting properties, a material having acceptor properties, and a fluoride of an alkali metal or an alkaline earth metal can be used for a material having hole injecting properties. In particular, a composite material in which the fluorine atoms are 20% or more in atomic ratio can be preferably used. Thereby, the refractive index of layer 111 can be decreased. Or, a layer having a low refractive index can be formed inside the light-emitting device. Or, the external quantum efficiency of the light-emitting device can be improved.

[0227] Note that this embodiment can be appropriately combined with other embodiments described in this specification.

[0228] (Embodiment 5) In this embodiment, a light-emitting device using the light-emitting device described in any one of Embodiments 1 to 4 will be described.

[0229] In this embodiment, a light-emitting device manufactured using the light-emitting device described in any one of Embodiments 1 to 4 will be described with reference to FIG. 4. Note that FIG. 4A is a top view showing the light-emitting device, and FIG. 4B is a cross-sectional view obtained by cutting FIG. 4A along A-B and C-D. This light-emitting device includes a drive circuit portion (source line drive circuit 601), a pixel portion 602, and a drive circuit portion (gate line drive circuit 603), which are indicated by dotted lines, as a means for controlling the light emission of the light-emitting device. Further, 604 is a sealing substrate, 605 is a sealing material, and the inside surrounded by the sealing material 605 is a space 607.

[0230] Note that the routing wiring 608 is a wiring for transmitting signals input to the source line drive circuit 601 and the gate line drive circuit 603, and receives a video signal, a clock signal, a start signal, a reset signal, etc. from an FPC (flexible printed circuit) 609 serving as an external input terminal. Although only the FPC is illustrated here, a printed wiring board (PWB) may be attached to this FPC. The light-emitting device in this specification includes not only the light-emitting device main body but also a state in which an FPC or a PWB is attached thereto.

[0231] Next, the cross-sectional structure will be described with reference to FIG. 4B. Although a drive circuit section and a pixel section are formed on the element substrate 610, here, a source line drive circuit 601 which is a drive circuit section and one pixel in the pixel section 602 are shown.

[0232] The element substrate 610 may be made of a substrate such as glass, quartz, organic resin, metal, alloy, semiconductor, or a plastic substrate made of FRP (Fiber Reinforced Plastics), PVF (polyvinyl fluoride), polyester, acrylic resin, etc.

[0233] The structure of the transistor used for the pixel or the drive circuit is not particularly limited. For example, it may be an inverted staggered type transistor or a staggered type transistor. Also, it may be a top gate type transistor or a bottom gate type transistor. The semiconductor material used for the transistor is not particularly limited, and for example, silicon, germanium, silicon carbide, gallium nitride, etc. can be used. Alternatively, an oxide semiconductor containing at least one of indium, gallium, and zinc such as an In-Ga-Zn based metal oxide may be used.

[0234] The crystallinity of the semiconductor material used for the transistor is also not particularly limited, and any of an amorphous semiconductor, a semiconductor having crystallinity (microcrystalline semiconductor, polycrystalline semiconductor, single crystal semiconductor, or a semiconductor having a crystal region in part) may be used. Using a semiconductor having crystallinity is preferable because deterioration of transistor characteristics can be suppressed.

[0235] Here, in addition to the transistor provided in the pixel or the drive circuit, for semiconductor devices such as transistors used for a touch sensor described later, it is preferable to apply an oxide semiconductor. In particular, it is preferable to apply an oxide semiconductor having a wider bandgap than silicon. By using an oxide semiconductor having a wider bandgap than silicon, the current in the off state of the transistor can be reduced.

[0236] The above-mentioned oxide semiconductor preferably contains at least indium (In) or zinc (Zn). More preferably, it is an oxide semiconductor containing an oxide represented by In-M-Zn system oxide (M is a metal such as Al, Ti, Ga, Ge, Y, Zr, Sn, La, Ce or Hf).

[0237] In particular, as the semiconductor layer, it is preferable to use an oxide semiconductor film having a plurality of crystal parts, wherein the c-axis of the crystal part is oriented perpendicular to the surface to be formed of the semiconductor layer or the upper surface of the semiconductor layer, and there is no grain boundary between adjacent crystal parts.

[0238] By using such a material as the semiconductor layer, fluctuations in electrical characteristics can be suppressed, and a highly reliable transistor can be realized.

[0239] In addition, due to its low off-current, the transistor having the above-mentioned semiconductor layer can hold the charge accumulated in the capacitor through the transistor for a long period of time. By applying such a transistor to a pixel, it is also possible to stop the drive circuit while maintaining the gradation of the image displayed in each display area. As a result, an electronic device with extremely low power consumption can be realized.

[0240] For the purpose of stabilizing the characteristics of the transistor, etc., it is preferable to provide an underlying film. As the underlying film, an inorganic insulating film such as a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or a silicon nitride oxide film can be used, and it can be formed as a single layer or by lamination. The underlying film can be formed by a sputtering method, a CVD (Chemical Vapor Deposition) method (such as a plasma CVD method, a thermal CVD method, an MOCVD (Metal Organic CVD) method, etc.), an ALD (Atomic Layer Deposition) method, a coating method, a printing method, etc. Note that the underlying film may not be provided if not necessary.

[0241] Note that FET623 represents one of the transistors formed in the source line drive circuit 601. Also, the drive circuit may be formed of various CMOS circuits, PMOS circuits, or NMOS circuits. Further, in this embodiment, a driver integrated type in which the drive circuit is formed on the substrate is shown, but this is not necessarily required, and the drive circuit can also be formed externally instead of on the substrate.

[0242] Also, the pixel portion 602 is formed of a plurality of pixels including a switching FET611, a current control FET612, and a first electrode 613 electrically connected to its drain, but is not limited thereto, and may be a pixel portion combining three or more FETs and a capacitive element.

[0243] Note that an insulator 614 is formed covering the end of the first electrode 613. Here, it can be formed by using a positive photosensitive acrylic resin film.

[0244] Also, in order to make the coating property of the EL layer or the like formed later good, a curved surface having a curvature is formed at the upper end or the lower end of the insulator 614. For example, when a positive photosensitive acrylic resin is used as the material of the insulator 614, it is preferable to provide a curved surface having a curvature radius (0.2 μm or more and 3 μm or less) only at the upper end of the insulator 614. Also, either a negative photosensitive resin or a positive photosensitive resin can be used as the insulator 614.

[0245] On the first electrode 613, an EL layer 616 and a second electrode 617 are respectively formed. Here, as the material used for the first electrode 613 that functions as an anode, it is desirable to use a material with a large work function. For example, in addition to single-layer films such as ITO films, indium tin oxide films containing silicon, indium oxide films containing 2 wt% or more and 20 wt% or less of zinc oxide, titanium nitride films, chromium films, tungsten films, Zn films, Pt films, etc., a laminate of a titanium nitride film and a film mainly composed of aluminum, a three-layer structure of a titanium nitride film, a film mainly composed of aluminum, and a titanium nitride film, etc. can be used. Note that when a laminated structure is used, the resistance as a wiring is low, good ohmic contact can be achieved, and it can further function as an anode.

[0246] Also, the EL layer 616 is formed by various methods such as a vapor deposition method using a vapor deposition mask, an inkjet method, and a spin coating method. The EL layer 616 includes the configuration as described in any one of Embodiments 1 to 4. Further, as other materials constituting the EL layer 616, low molecular compounds or high molecular compounds (including oligomers and dendrimers) may be used.

[0247] Furthermore, as the material used for the second electrode 617 formed on the EL layer 616 and functioning as a cathode, it is preferable to use a material with a small work function (Al, Mg, Li, Ca, or their alloys or compounds (MgAg, MgIn, AlLi, etc.)). Note that when the light generated in the EL layer 616 is transmitted through the second electrode 617, it is good to use a laminate of a thin metal film with a reduced film thickness and a transparent conductive film (ITO, indium oxide containing 2 wt% or more and 20 wt% or less of zinc oxide, indium tin oxide containing silicon, zinc oxide (ZnO), etc.) as the second electrode 617.

[0248] Note that a light-emitting device is formed by the first electrode 613, the EL layer 616, and the second electrode 617. The light-emitting device is the light-emitting device described in any one of Embodiments 1 to 4. Note that a plurality of light-emitting devices are formed in the pixel portion, and in the light-emitting device of the present embodiment, both the light-emitting device described in any one of Embodiments 1 to 4 and the light-emitting device having other configurations may be mixed.

[0249] Furthermore, by bonding the sealing substrate 604 to the element substrate 610 with the sealing material 605, a structure is formed in which the light-emitting device 618 is provided in the space 607 surrounded by the element substrate 610, the sealing substrate 604, and the sealing material 605. Note that the space 607 is filled with a filling material, and in addition to the case where an inert gas (such as nitrogen or argon) is filled, it may be filled with a sealing material. By forming a concave portion in the sealing substrate and providing a drying material therein, deterioration due to the influence of moisture can be suppressed, which is a preferable configuration.

[0250] Note that it is preferable to use an epoxy-based resin or glass frit for the sealing material 605. Further, it is desirable that these materials hardly transmit moisture and oxygen. In addition to a glass substrate or a quartz substrate, a plastic substrate made of FRP (Fiber Reinforced Plastics), PVF (polyvinyl fluoride), polyester, acrylic resin, or the like can be used as the material for the sealing substrate 604.

[0251] Although not shown in FIGS. 4A and 4B, a protective film may be provided on the second electrode. The protective film may be formed of an organic resin film or an inorganic insulating film. Further, the protective film may be formed so as to cover the exposed portion of the sealing material 605. Further, the protective film can be provided so as to cover the exposed side surfaces of the surfaces and side surfaces of the pair of substrates, the sealing layer, the insulating layer, and the like.

[0252] For the protective film, a material that is difficult to permeate impurities such as water can be used. Therefore, it is possible to effectively suppress the diffusion of impurities such as water from the outside to the inside.

[0253] As the material constituting the protective film, oxides, nitrides, fluorides, sulfides, ternary compounds, metals, polymers, etc. can be used. For example, materials containing aluminum oxide, hafnium oxide, hafnium silicate, lanthanum oxide, silicon oxide, strontium titanate, tantalum oxide, titanium oxide, zinc oxide, niobium oxide, zirconium oxide, tin oxide, yttrium oxide, cerium oxide, scandium oxide, erbium oxide, vanadium oxide or indium oxide, etc., or materials containing aluminum nitride, hafnium nitride, silicon nitride, tantalum nitride, titanium nitride, niobium nitride, molybdenum nitride, zirconium nitride or gallium nitride, etc., nitrides containing titanium and aluminum, oxides containing titanium and aluminum, oxides containing aluminum and zinc, sulfides containing manganese and zinc, sulfides containing cerium and strontium, oxides containing erbium and aluminum, oxides containing yttrium and zirconium, etc. can be used.

[0254] The protective film is preferably formed using a film-forming method with good step coverage. One such technique is the atomic layer deposition (ALD) method. It is preferable to use a material that can be formed using the ALD method for the protective film. By using the ALD method, a protective film that is dense, has reduced defects such as cracks or pinholes, or has a uniform thickness can be formed. Also, the damage given to the processing member when forming the protective film can be reduced.

[0255] For example, by forming the protective film using the ALD method, a protective film that is uniform and has few defects can be formed on a surface having a complex uneven shape or on the upper, side, and back surfaces of a touch panel.

[0256] As described above, a light-emitting device manufactured using the light-emitting device according to any one of Embodiments 1 to 4 can be obtained.

[0257] Since the light-emitting device in this embodiment uses the light-emitting device according to any one of Embodiments 1 to 4, a light-emitting device having good characteristics can be obtained. Specifically, since the light-emitting device according to any one of Embodiments 1 to 4 has good luminous efficiency, it is possible to obtain a light-emitting device with low power consumption.

[0258] FIG. 5 shows an example of a full-color light-emitting device formed by forming a light-emitting device that exhibits white light emission and providing a coloring layer (color filter) or the like. FIG. 5A shows a substrate 1001, an underlying insulating film 1002, a gate insulating film 1003, gate electrodes 1006, 1007, 1008, a first interlayer insulating film 1020, a second interlayer insulating film 1021, a peripheral portion 1042, a pixel portion 1040, a drive circuit portion 1041, first electrodes 1024W, 1024R, 1024G, 1024B of the light-emitting device, a partition 1025, an EL layer 1028, a second electrode 1029 of the light-emitting device, a sealing substrate 1031, a sealing material 1032, and the like.

[0259] Also, in FIG. 5A, the coloring layers (red coloring layer 1034R, green coloring layer 1034G, blue coloring layer 1034B) are provided on a transparent base material 1033. Further, a black matrix 1035 may be provided. The transparent base material 1033 provided with the coloring layer and the black matrix is aligned and fixed to the substrate 1001. Note that the coloring layer and the black matrix 1035 are covered with an overcoat layer 1036. Also, in FIG. 5A, there are a light-emitting layer in which light does not pass through the coloring layer and exits to the outside, and a light-emitting layer in which light passes through the coloring layers of each color and exits to the outside. Since the light that does not pass through the coloring layer is white, and the light that passes through the coloring layer is red, green, or blue, an image can be expressed with four-color pixels.

[0260] In FIG. 5B, an example is shown in which the coloring layers (red coloring layer 1034R, green coloring layer 1034G, blue coloring layer 1034B) are formed between the gate insulating film 1003 and the first interlayer insulating film 1020. Thus, the coloring layers may be provided between the substrate 1001 and the sealing substrate 1031.

[0261] In addition, in the light-emitting device described above, the light-emitting device has a structure (bottom emission type) in which light is extracted from the substrate 1001 side where the FET is formed, but a structure (top emission type) in which light is extracted from the sealing substrate 1031 side may also be used. A cross-sectional view of the top emission type light-emitting device is shown in FIG. 6. In this case, a substrate that does not transmit light can be used for the substrate 1001. Until the connection electrodes connecting the FET and the anode of the light-emitting device are fabricated, the device is formed in the same manner as the bottom emission type light-emitting device. Thereafter, a third interlayer insulating film 1037 is formed to cover the electrode 1022. This insulating film may serve as a planarization film. The third interlayer insulating film 1037 can be formed using the same material as the second interlayer insulating film, or other known materials.

[0262] The first electrodes 1024W, 1024R, 1024G, and 1024B of the light-emitting device are anodes here, but they may be cathodes. Also, in the case of a top emission type light-emitting device as shown in FIG. 6, it is preferable that the first electrode is a reflective electrode. The configuration of the EL layer 1028 is the same as the configuration described as the unit 103 in any one of Embodiments 1 to 4, and has an element structure that can obtain white light emission.

[0263] In a top emission structure as shown in FIG. 6, sealing can be performed with a sealing substrate 1031 provided with a coloring layer (red coloring layer 1034R, green coloring layer 1034G, blue coloring layer 1034B). A black matrix 1035 may be provided on the sealing substrate 1031 so as to be located between pixels. The coloring layer (red coloring layer 1034R, green coloring layer 1034G, blue coloring layer 1034B) or the black matrix may be covered with an overcoat layer 1036. Note that a substrate having translucency is used as the sealing substrate 1031. Here, an example of full-color display using four colors of red, green, blue, and white is shown, but it is not particularly limited, and full-color display may be performed using four colors of red, yellow, green, and blue or three colors of red, green, and blue.

[0264] In a top emission type light-emitting device, application of a microcavity structure can be suitably performed. A light-emitting device having a microcavity structure can be obtained by using a first electrode as a reflective electrode and a second electrode as a semi-transmissive / semi-reflective electrode. At least an EL layer is provided between the reflective electrode and the semi-transmissive / semi-reflective electrode, and at least a light-emitting layer serving as a light-emitting region is provided.

[0265] Note that the reflective electrode has a visible light reflectance of 40% to 100%, preferably 70% to 100%, and a resistivity of 1×10 -2 Ωcm or less. Further, the semi-transmissive / semi-reflective electrode has a visible light reflectance of 20% to 80%, preferably 40% to 70%, and a resistivity of 1×10 -2 Ωcm or less.

[0266] Light emitted from the light-emitting layer included in the EL layer is reflected by the reflective electrode and the semi-transmissive / semi-reflective electrode and resonates.

[0267] The optical distance between the reflective electrode and the semi-transmissive / semi-reflective electrode of the light-emitting device can be changed by changing the thicknesses of a transparent conductive film or the above-described composite material, carrier transport material, or the like. Thereby, between the reflective electrode and the semi-transmissive / semi-reflective electrode, light having a resonant wavelength can be enhanced and light having a non-resonant wavelength can be attenuated.

[0268] Note that, since the light (first reflected light) reflected by the reflective electrode and returned causes significant interference with the light (first incident light) directly incident from the light-emitting layer on the semi-transmissive / semi-reflective electrode, it is preferable to adjust the optical distance between the reflective electrode and the light-emitting layer to (2n - 1)λ / 4 (where n is a natural number of 1 or more and λ is the wavelength of the light emission to be amplified). By adjusting the optical distance, the phases of the first reflected light and the first incident light can be matched, and the light emission from the light-emitting layer can be amplified more.

[0269] Note that, in the above configuration, the EL layer may have a structure with a plurality of light-emitting layers or a structure with a single light-emitting layer. For example, in combination with the configuration of the tandem-type light-emitting device described above, it may be applied to a configuration in which a plurality of EL layers are provided with a charge generation layer sandwiched between them in one light-emitting device, and a single or a plurality of light-emitting layers are formed in each EL layer.

[0270] By having a microcavity structure, it becomes possible to enhance the light emission intensity in the front direction of a specific wavelength, and thus power consumption can be reduced. In the case of a light-emitting device that displays an image with four sub-pixels of red, yellow, green, and blue, in addition to the luminance improvement effect by yellow light emission, a microcavity structure can be applied for each color wavelength in all the sub-pixels, resulting in a light-emitting device with good characteristics.

[0271] Since the light-emitting device in the present embodiment uses the light-emitting device described in any one of Embodiments 1 to 4, a light-emitting device with good characteristics can be obtained. Specifically, since the light-emitting device described in any one of Embodiments 1 to 4 has good luminous efficiency, it is possible to make a light-emitting device with low power consumption.

[0272] So far, the active matrix light-emitting device has been described. From the following, a passive matrix light-emitting device will be described. FIG. 7 shows a passive matrix light-emitting device manufactured by applying the present invention. Note that FIG. 7A is a perspective view showing the light-emitting device, and FIG. 7B is a cross-sectional view obtained by cutting FIG. 7A along the X-Y plane. In FIG. 7, an EL layer 955 is provided between an electrode 952 and an electrode 956 on a substrate 951. The end of the electrode 952 is covered with an insulating layer 953. Then, a partition layer 954 is provided on the insulating layer 953. The side walls of the partition layer 954 have an inclination such that the distance between one side wall and the other side wall becomes narrower as it approaches the substrate surface. That is, the cross-section of the partition layer 954 in the short side direction is trapezoidal, and the bottom side (the side facing the same direction as the surface direction of the insulating layer 953 and in contact with the insulating layer 953) is shorter than the upper side (the side facing the same direction as the surface direction of the insulating layer 953 and not in contact with the insulating layer 953). By providing the partition layer 954 in this way, it is possible to prevent defects in the light-emitting device caused by static electricity or the like. Also, in the passive matrix light-emitting device, the light-emitting device described in any one of Embodiments 1 to 4 is used, and a light-emitting device with good reliability or a light-emitting device with low power consumption can be obtained.

[0273] As described above, since the light-emitting device can control each of a large number of minute light-emitting devices arranged in a matrix, it is a light-emitting device that can be suitably used as a display device for image display.

[0274] In addition, this embodiment can be freely combined with other embodiments.

[0275] (Embodiment 6) In this embodiment, an example in which the light-emitting device described in any one of Embodiments 1 to 4 is used as an illumination device will be described with reference to FIG. 8. FIG. 8B is a top view of the illumination device, and FIG. 8A is a cross-sectional view taken along the e-f plane in FIG. 8B.

[0276] In the lighting device according to the present embodiment, a first electrode 401 is formed on a translucent substrate 400 that is a support. The first electrode 401 corresponds to the electrode 101 in any one of Embodiments 1 to 4. When extracting light emission from the first electrode 401 side, the first electrode 401 is formed of a translucent material.

[0277] A pad 412 for supplying a voltage to the second electrode 404 is formed on the substrate 400.

[0278] An EL layer 403 is formed on the first electrode 401. The EL layer 403 corresponds to the configuration of the unit 103 in any one of Embodiments 1 to 4, or the combined configuration of the unit 103(2), layer 104, layer 105, and intermediate layer 106. For these configurations, please refer to the relevant description.

[0279] The second electrode 404 is formed to cover the EL layer 403. The second electrode 404 corresponds to the electrode 102 in any one of Embodiments 1 to 4. When extracting light emission from the first electrode 401 side, the second electrode 404 is formed of a material with high reflectivity. The second electrode 404 is connected to the pad 412 to supply a voltage.

[0280] As described above, the lighting device according to the present embodiment has a light-emitting device having the first electrode 401, the EL layer 403, and the second electrode 404. Since the light-emitting device has high luminous efficiency, the lighting device according to the present embodiment can be a lighting device with low power consumption.

[0281] The lighting device is completed by fixing and sealing the substrate 400 on which the light-emitting device having the above configuration is formed and a sealing substrate 407 using sealing materials 405 and 406. Either of the sealing materials 405 and 406 may be used. Further, a desiccant can be mixed into the inner sealing material 406 (not shown in FIG. 8B), whereby moisture can be adsorbed, leading to an improvement in reliability.

[0282] Further, by extending and providing a part of the pad 412 and the first electrode 401 outside the sealing materials 405 and 406, it can be used as an external input terminal. Also, an IC chip 420 with a converter or the like mounted thereon may be provided.

[0283] As described above, the lighting device according to the present embodiment uses the light-emitting device described in any one of Embodiments 1 to 4 for the EL element, and can be a lighting device with low power consumption.

[0284] (Embodiment 7) In the present embodiment, an example of an electronic device including, in a part thereof, the light-emitting device described in any one of Embodiments 1 to 4 will be described. The light-emitting device described in any one of Embodiments 1 to 4 is a light-emitting device with good luminous efficiency and low power consumption. As a result, the electronic device described in the present embodiment can be an electronic device having a light-emitting portion with low power consumption.

[0285] Examples of electronic devices to which the above light-emitting device is applied include, for example, a television device (also referred to as a TV or a television receiver), a monitor for a computer, a digital camera, a digital video camera, a digital photo frame, a mobile phone (also referred to as a cellular phone or a mobile phone device), a portable game machine, a portable information terminal, an audio reproduction device, and a large game machine such as a pachinko machine. Specific examples of these electronic devices are shown below.

[0286] FIG. 9A shows an example of a television device. In the television device, a display unit 7103 is incorporated in a housing 7101. Here, a configuration in which the housing 7101 is supported by a stand 7105 is shown. The display unit 7103 can display video, and the display unit 7103 is configured by arranging the light-emitting devices described in any one of Embodiments 1 to 4 in a matrix.

[0287] The operation of the television device can be performed by an operation switch provided on the housing 7101 or by a separate remote control operation unit 7110. Channel or volume operations can be performed using the operation keys 7109 provided on the remote control operation unit 7110, and the video displayed on the display unit 7103 can be operated. Further, the remote control operation unit 7110 may be configured to include a display unit 7107 for displaying information output from the remote control operation unit 7110.

[0288] In addition, the television device is configured to include a receiver or a modem, etc. General television broadcasts can be received by the receiver, and by connecting to a wired or wireless communication network via the modem, one-way (sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication can also be performed.

[0289] FIG. 9B shows a computer, including a main body 7201, a housing 7202, a display unit 7203, a keyboard 7204, an external connection port 7205, a pointing device 7206, etc. Note that this computer is manufactured by arranging the light-emitting devices described in any one of Embodiments 1 to 4 in a matrix and using them for the display unit 7203. The computer in FIG. 9B may be in the form shown in FIG. 9C. The computer in FIG. 9C is provided with a second display unit 7210 instead of the keyboard 7204 and the pointing device 7206. The second display unit 7210 is a touch panel type, and input can be performed by operating the input display shown on the second display unit 7210 with a finger or a dedicated pen. In addition, the second display unit 7210 can display not only input displays but also other images. Also, the display unit 7203 may be a touch panel. By connecting the two screens with a hinge, it is possible to prevent problems such as damage or breakage of the screens when storing or transporting.

[0290] FIG. 9D shows an example of a mobile terminal. The mobile phone includes, in addition to a display unit 7402 incorporated in a housing 7401, operation buttons 7403, an external connection port 7404, a speaker 7405, a microphone 7406, and the like. Note that the mobile phone has a display unit 7402 manufactured by arranging the light-emitting devices described in any one of Embodiments 1 to 4 in a matrix form.

[0291] The mobile terminal shown in FIG. 9D may be configured such that information can be input by touching the display unit 7402 with a finger or the like. In this case, operations such as making a call or creating an e-mail can be performed by touching the display unit 7402 with a finger or the like.

[0292] The screen of the display unit 7402 mainly has three modes. The first is a display mode mainly for displaying images, the second is an input mode mainly for inputting information such as characters, and the third is a display + input mode in which the two modes of the display mode and the input mode are mixed.

[0293] For example, when making a call or creating an e-mail, the display unit 7402 may be set to a character input mode mainly for inputting characters, and an input operation of the characters displayed on the screen may be performed. In this case, it is preferable to display a keyboard or number buttons on most of the screen of the display unit 7402.

[0294] In addition, by providing a detection device having sensors such as a gyro and an acceleration sensor inside the mobile terminal to detect the inclination, the orientation (portrait or landscape) of the mobile terminal can be determined, and the screen display of the display unit 7402 can be automatically switched.

[0295] The switching of the screen mode is performed by touching the display unit 7402 or operating the operation buttons 7403 of the housing 7401. It can also be switched according to the type of image displayed on the display unit 7402. For example, if the image signal displayed on the display unit is video data, it is switched to the display mode, and if it is text data, it is switched to the input mode.

[0296] Also, in the input mode, when detecting a signal detected by the light sensor of the display unit 7402 and there is no input by the touch operation of the display unit 7402 for a certain period, it may be controlled to switch the screen mode from the input mode to the display mode.

[0297] The display unit 7402 can also function as an image sensor. For example, by touching the display unit 7402 with a palm or a finger and imaging a palm print, a fingerprint, etc., personal authentication can be performed. Also, if a backlight that emits near-infrared light or a sensing light source that emits near-infrared light is used for the display unit, finger veins, palm veins, etc. can also be imaged.

[0298] FIG. 10A is a schematic diagram showing an example of a cleaning robot.

[0299] The cleaning robot 5100 has a display 5101 arranged on the upper surface, a plurality of cameras 5102 arranged on the side surface, a brush 5103, and an operation button 5104. Although not shown, the lower surface of the cleaning robot 5100 is provided with tires, a suction port, etc. The cleaning robot 5100 is further provided with various sensors such as an infrared sensor, an ultrasonic sensor, an acceleration sensor, a piezo sensor, a light sensor, and a gyro sensor. Also, the cleaning robot 5100 is provided with wireless communication means.

[0300] The cleaning robot 5100 can move automatically, detect dust 5120, and suck the dust from the suction port provided on the lower surface.

[0301] Also, the cleaning robot 5100 can analyze the image taken by the camera 5102 and determine the presence or absence of obstacles such as walls, furniture, or steps. Also, when an object that is likely to get caught in the brush 5103, such as wiring, is detected by image analysis, the rotation of the brush 5103 can be stopped.

[0302] The display 5101 can display the remaining battery level, the amount of dust sucked, etc. The display 5101 may display the route traveled by the cleaning robot 5100. Further, the display 5101 may be a touch panel, and the operation buttons 5104 may be provided on the display 5101.

[0303] The cleaning robot 5100 can communicate with a portable electronic device 5140 such as a smartphone. The image captured by the camera 5102 can be displayed on the portable electronic device 5140. Therefore, the owner of the cleaning robot 5100 can know the state of the room even when away from home. Also, the display on the display 5101 can be confirmed on a portable electronic device 5140 such as a smartphone.

[0304] The light-emitting device according to one aspect of the present invention can be used for the display 5101.

[0305] The robot 2100 shown in FIG. 10B includes an arithmetic unit 2110, an illuminance sensor 2101, a microphone 2102, an upper camera 2103, a speaker 2104, a display 2105, a lower camera 2106, an obstacle sensor 2107, and a moving mechanism 2108.

[0306] The microphone 2102 has a function of detecting the user's voice and environmental sounds, etc. Also, the speaker 2104 has a function of emitting sound. The robot 2100 can communicate with the user using the microphone 2102 and the speaker 2104.

[0307] The display 2105 has a function of displaying various information. The robot 2100 can display the information desired by the user on the display 2105. The display 2105 may be equipped with a touch panel. Also, the display 2105 may be a removable information terminal, and by installing it at a fixed position of the robot 2100, charging and data transfer are made possible.

[0308] The upper camera 2103 and the lower camera 2106 have the function of imaging the surroundings of the robot 2100. Also, the obstacle sensor 2107 can detect the presence or absence of obstacles in the traveling direction when the robot 2100 moves forward using the moving mechanism 2108. The robot 2100 can recognize the surrounding environment and move safely using the upper camera 2103, the lower camera 2106, and the obstacle sensor 2107. The light-emitting device according to one aspect of the present invention can be used for the display 2105.

[0309] FIG. 10C is a diagram showing an example of a goggle-type display. The goggle-type display includes, for example, a housing 5000, a display unit 5001, a speaker 5003, an LED lamp 5004, a connection terminal 5006, a sensor 5007 (including a function of measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays), a microphone 5008, a display unit 5002, a support unit 5012, earphones 5013, and the like.

[0310] The light-emitting device according to one aspect of the present invention can be used for the display unit 5001 and the display unit 5002.

[0311] FIG. 11 is an example in which the light-emitting device according to any one of Embodiments 1 to 4 is used in an electric stand which is a lighting device. The electric stand shown in FIG. 11 has a housing 2001 and a light source 2002, and as the light source 2002, the lighting device described in Embodiment 6 may be used.

[0312] FIG. 12 shows an example in which the light-emitting device described in any one of Embodiments 1 to 4 is used as an indoor lighting device 3001. Since the light-emitting device described in any one of Embodiments 1 to 4 is a light-emitting device with high luminous efficiency, it can be made into a lighting device with low power consumption. In addition, since the light-emitting device described in any one of Embodiments 1 to 4 can be made into a large area, it can be used as a large-area lighting device. Further, since the light-emitting device described in any one of Embodiments 1 to 4 is thin, it can be used as a thin lighting device.

[0313] The light-emitting device described in any one of Embodiments 1 to 4 can also be mounted on the windshield or dashboard of an automobile. FIG. 13 shows one aspect in which the light-emitting device described in any one of Embodiments 1 to 4 is used for the windshield or dashboard of an automobile. Display areas 5200 to 5203 are display areas provided using the light-emitting device described in any one of Embodiments 1 to 4.

[0314] Display area 5200 and display area 5201 are display devices equipped with the light-emitting device described in any one of Embodiments 1 to 4 provided on the windshield of an automobile. The light-emitting device described in any one of Embodiments 1 to 4 can be made into a so-called see-through display device in which the opposite side can be seen through by fabricating the first electrode and the second electrode with light-transmissive electrodes. In the case of a see-through display, even if it is installed on the windshield of an automobile, it can be installed without obstructing the view. When providing a transistor or the like for driving, it is preferable to use a light-transmissive transistor such as an organic transistor made of an organic semiconductor material or a transistor using an oxide semiconductor.

[0315] The display area 5202 is a display device equipped with the light-emitting device according to any one of Embodiments 1 to 4 provided in the pillar portion. The display area 5202 can complement the field of view blocked by the pillar by projecting the video from the imaging means provided on the vehicle body. Similarly, the display area 5203 provided in the dashboard portion can complement the field of view blocked by the vehicle body and enhance safety by projecting the video from the imaging means provided outside the vehicle to make up for the blind spot. By projecting the video so as to complement the invisible portion, it is possible to perform safety confirmation more naturally without a sense of discomfort.

[0316] The display area 5203 can provide various information by displaying navigation information, speed or rotation, travel distance, remaining fuel amount, gear state, air conditioning settings, etc. The display can appropriately change the display items or layout according to the user's preference. Note that these information can also be provided in the display areas 5200 to 5202. In addition, the display areas 5200 to 5203 can also be used as lighting devices.

[0317] Also, FIGS. 14A to 14C show a foldable portable information terminal 9310. FIG. 14A shows the portable information terminal 9310 in the unfolded state. FIG. 14B shows the portable information terminal 9310 in a state changing from one of the unfolded state or the folded state to the other. FIG. 14C shows the portable information terminal 9310 in the folded state. The portable information terminal 9310 has excellent portability in the folded state and excellent display listability due to a seamless wide display area in the unfolded state.

[0318] The display panel 9311 is supported by three housings 9315 connected by a hinge 9313. Note that the display panel 9311 may be a touch panel (input / output device) equipped with a touch sensor (input device). Also, the display panel 9311 can be reversibly deformed from the unfolded state to the folded state of the portable information terminal 9310 by bending between the two housings 9315 via the hinge 9313. The light-emitting device according to one aspect of the present invention can be used for the display panel 9311.

[0319] Note that the configuration shown in this embodiment can be used by appropriately combining the configurations shown in Embodiments 1 to 4.

[0320] As described above, the application range of the light-emitting device including the light-emitting device described in any one of Embodiments 1 to 4 is extremely wide, and this light-emitting device can be applied to electronic devices in all fields. By using the light-emitting device described in any one of Embodiments 1 to 4, an electronic device with low power consumption can be obtained.

[0321] Note that this embodiment can be appropriately combined with other embodiments shown in this specification.

Example

[0322] In this example, the structures, manufacturing methods, and characteristics of the light-emitting devices 1 to 5 according to one aspect of the present invention will be described with reference to FIGS. 15 to 51.

[0323] FIGS. 15A and 15B are cross-sectional views for explaining the configuration of the manufactured light-emitting device.

[0324] FIG. 16 is a diagram for explaining the current density-luminance characteristics of the light-emitting device 1.

[0325] FIG. 17 is a diagram for explaining the luminance-current efficiency characteristics of the light-emitting device 1.

[0326] FIG. 18 is a diagram for explaining the voltage-luminance characteristics of the light-emitting device 1.

[0327] FIG. 19 is a diagram for explaining the voltage-current characteristics of the light-emitting device 1.

[0328] FIG. 20 is a diagram for explaining the luminance-external quantum efficiency characteristics of the light-emitting device 1. Note that assuming the light distribution characteristics of the light-emitting device are of the Lambertian type, the external quantum efficiency was calculated from the luminance observed from the front and the emission spectrum.

[0329] FIG. 21 is a diagram for explaining the emission spectrum when the light-emitting device 1 emits light at a luminance of 1000 cd / m 2 of.

[0330] FIG. 22 is a diagram for explaining the normalized luminance-time change characteristics when the light-emitting device 1 emits light at a constant current density of 50 mA / cm 2 . Note that the normalized luminance-time change characteristics when the comparative light-emitting device emits light at a constant current density of 50 mA / cm 2 are also shown.

[0331] FIG. 23 is a diagram for explaining the current density-luminance characteristics of the light-emitting device 2.

[0332] FIG. 24 is a diagram for explaining the luminance-current efficiency characteristics of the light-emitting device 2.

[0333] FIG. 25 is a diagram for explaining the voltage-luminance characteristics of the light-emitting device 2.

[0334] FIG. 26 is a diagram for explaining the voltage-current characteristics of the light-emitting device 2.

[0335] FIG. 27 is a diagram for explaining the luminance-external quantum efficiency characteristics of the light-emitting device 2. Note that assuming the light distribution characteristics of the light-emitting device are of the Lambertian type, the external quantum efficiency was calculated from the luminance observed from the front and the emission spectrum.

[0336] FIG. 28 is when the light-emitting device 2 is at 1000 cd / m 2This is a diagram for explaining the emission spectrum when light is emitted at the luminance of

[0337] Figure 29 is a diagram for explaining the normalized luminance-time change characteristics when the light-emitting device 2 is caused to emit light at a constant current density of 50 mA / cm 2 The normalized luminance-time change characteristics when the comparative light-emitting device is caused to emit light at a constant current density of 50 mA / cm 2 are also shown.

[0338] Figure 30 is a diagram for explaining the current density-luminance characteristics of the light-emitting device 3.

[0339] Figure 31 is a diagram for explaining the luminance-current efficiency characteristics of the light-emitting device 3.

[0340] Figure 32 is a diagram for explaining the voltage-luminance characteristics of the light-emitting device 3.

[0341] Figure 33 is a diagram for explaining the voltage-current characteristics of the light-emitting device 3.

[0342] Figure 34 is a diagram for explaining the luminance-external quantum efficiency characteristics of the light-emitting device 3. The external quantum efficiency was calculated from the luminance and emission spectrum observed from the front, assuming that the light distribution characteristics of the light-emitting device are of the Lambertian type.

[0343] Figure 35 is a diagram for explaining the emission spectrum when the light-emitting device 3 is caused to emit light at a luminance of 1000 cd / m 2

[0344] Figure 36 is a diagram for explaining the normalized luminance-time change characteristics when the light-emitting device 3 is caused to emit light at a constant current density of 50 mA / cm 2 The normalized luminance-time change characteristics when the comparative light-emitting device is caused to emit light at a constant current density of 50 mA / cm 2 are also shown.

[0345] Figure 37 is a diagram for explaining the current density-luminance characteristics of the light-emitting device 4.

[0346] ​FIG. 38 is a diagram for explaining the luminance-current efficiency characteristics of the light-emitting device 4.

[0347] FIG. 39 is a diagram for explaining the voltage-luminance characteristics of the light-emitting device 4.

[0348] FIG. 40 is a diagram for explaining the voltage-current characteristics of the light-emitting device 4.

[0349] FIG. 41 is a diagram for explaining the luminance-external quantum efficiency characteristics of the light-emitting device 4. Note that assuming the light distribution characteristics of the light-emitting device are of the Lambertian type, the external quantum efficiency was calculated from the luminance and emission spectrum observed from the front.

[0350] FIG. 42 is a diagram for explaining the emission spectrum when the light-emitting device 4 emits light at a luminance of 1000 cd / m 2 of the emission spectrum when the light-emitting device 4 emits light at a luminance of 1000 cd / m.

[0351] FIG. 43 is a diagram for explaining the normalized luminance-time change characteristics when the light-emitting device 4 emits light at a constant current density of 50 mA / cm 2 Note that the normalized luminance-time change characteristics when the comparative light-emitting device emits light at a constant current density of 50 mA / cm 2 are also shown.

[0352] FIGS. 44A and 44B are cross-sectional views for explaining the structure of the fabricated light-emitting device.

[0353] FIG. 45 is a diagram for explaining the current density-luminance characteristics of the light-emitting device 5.

[0354] FIG. 46 is a diagram for explaining the luminance-current efficiency characteristics of the light-emitting device 5.

[0355] FIG. 47 is a diagram for explaining the voltage-luminance characteristics of the light-emitting device 5.

[0356] FIG. 48 is a diagram for explaining the voltage-current characteristics of the light-emitting device 5.

[0357] FIG. 49 is a diagram for explaining the luminance-external quantum efficiency characteristics of the light-emitting device 5. Note that assuming that the light distribution characteristics of the light-emitting device are of the Lambertian type, the external quantum efficiency was calculated from the luminance and the emission spectrum observed from the front.

[0358] FIG. 50 is a diagram for explaining the emission spectrum when the light-emitting device 5 emits light at a luminance of 1000 cd / m 2 .

[0359] FIG. 51 is a diagram for explaining the normalized luminance-time change characteristics when the light-emitting device 5 emits light at a constant current density of 50 mA / cm 2 . Note that the normalized luminance-time change characteristics when a comparative light-emitting device emits light at a constant current density of 50 mA / cm 2 are also shown.

[0360] <Light-emitting device 1> The fabricated light-emitting device 1 described in this example has the same configuration as the light-emitting device 150 (see FIG. 15A). The light-emitting device 150 has an electrode 101, an electrode 102, a unit 103, and a layer 104, and the electrode 102 has a region overlapping with the electrode 101.

[0361] The unit 103 has a region sandwiched between the electrode 101 and the electrode 102, and the unit 103 has a layer 111 and a layer 112.

[0362] The layer 111 has a region sandwiching the layer 112 between it and the electrode 101, and the layer 111 contains a light-emitting material EM. Note that in the light-emitting device 1, 3,10PCA2Nbf(IV)-02 was used as the light-emitting material EM.

[0363] The layer 104 has a region sandwiched between the layer 112 and the electrode 101, and the layer 104 contains a material AM having acceptor properties and a material HT1, and the layer 104 has a region 104A and a region 104B. Note that in the light-emitting device 1, an electron acceptor material (abbreviation: OCHD-001) was used as the material AM having acceptor properties. Also, BBABnf was used as the material HT1.

[0364] Region 104A is a region sandwiched between region 104B and electrode 101. Region 104A contains material AM having acceptor properties at concentration C1, and region 104B contains material AM having acceptor properties at concentration C2. Note that concentration C2 is higher than zero and lower than concentration C1. In the light-emitting device 1, region 104A was formed using only OCHD-001, and region 104B was formed using BBABnf and OCHD-001.

[0365] Layer 112 includes region 112A and region 112B. Region 112B is a region sandwiched between layer 111 and region 112A, and region 112B contains material HT2. In the light-emitting device 1, PCzN2 was used as material HT2.

[0366] Also, material HT1 has a first HOMO level, and the first HOMO level was -5.7 eV or more and -5.4 eV or less. According to cyclic voltammetry (CV) measurement, the HOMO level of BBABnf was -5.56 eV.

[0367] Material HT2 has a second HOMO level, and the second HOMO level was in the range of -0.2 eV or more and 0 eV or less with respect to the first HOMO level. According to CV measurement, the HOMO level of PCzN2 was -5.71 eV.

[0368] Layer 113 is a region sandwiched between electrode 102 and layer 111. Layer 113 contains material OMC, and material OMC is an organic complex of an alkali metal or an organic complex of an alkaline earth metal. In the light-emitting device 1, Liq was used as material OMC.

[0369] Layer 111 contains host material HOST, and host material HOST has a first LUMO level. In the light-emitting device 1, αN-βNPAnth was used as host material HOST. Also, according to CV measurement, the LUMO level of αN-βNPAnth was -2.74 eV.

[0370] Unit 103 includes layer 113, layer 113 includes region 113A and region 113B, and region 113A includes a region sandwiched between region 113B and layer 111.

[0371] Region 113A contains material ET, and region 113B contains material OMC. Material ET has a second LUMO level. In the light-emitting device 1, ZADN was used as material ET. According to CV measurement, the LUMO level of ZADN was -2.87 eV. Therefore, the second LUMO level is in the range of -0.4 eV or more and -0.11 eV or less with respect to the first LUMO level.

[0372] Also, region 104A is in contact with electrode 101.

[0373] 《Configuration of Light-Emitting Device 1》 The configuration of light-emitting device 1 is shown in Table 1. Also, the structural formulas of the materials used in the light-emitting device described in this example are shown below.

[0374]

Table 1

[0375]

Chemical Formula

[0376] 《Calculation Method for HOMO Level and LUMO Level of Materials》 Regarding the HOMO level and LUMO level of the materials, they were calculated based on cyclic voltammetry (CV) measurement. The calculation method is shown below.

[0377] As the measuring device, an electrochemical analyzer (manufactured by BAS Inc., model number: ALS model 600A or 600C) was used. For the solution in CV measurement, dehydrated dimethylformamide (DMF) (manufactured by Aldrich Co., Ltd., 99.8%, catalog number: 22705-6) was used as the solvent, and tetra-n-butylammonium perchlorate (n-Bu4NClO4) (manufactured by Tokyo Chemical Industry Co., Ltd., catalog number: T0836), which is a supporting electrolyte, was dissolved to a concentration of 100 mmol / L, and further the measurement target was dissolved to a concentration of 2 mmol / L for preparation.

[0378] Also, as the working electrode, a platinum electrode (manufactured by BAS Inc., PTE platinum electrode) was used, as the auxiliary electrode, a platinum electrode (manufactured by BAS Inc., Pt counter electrode for VC-3 (5 cm)) was used, and as the reference electrode, an Ag / Ag + electrode (manufactured by BAS Inc., RE7 non-aqueous solvent-based reference electrode) was used respectively. Note that the measurement was carried out at room temperature (20 °C or more and 25 °C or less).

[0379] Also, the scan rate during CV measurement was unified to 0.1 V / sec, and the oxidation potential Ea [V] and reduction potential Ec [V] with respect to the reference electrode were measured. Ea was taken as the intermediate potential of the oxidation-reduction wave, and Ec was taken as the intermediate potential of the reduction-oxidation wave. Here, since it is known that the potential energy of the reference electrode used in this example with respect to the vacuum level is -4.94 [eV], the HOMO level [eV] = -4.94 - Ea and the LUMO level [eV] = -4.94 - Ec, and the HOMO level and LUMO level can be obtained respectively from these formulas.

[0380] 《Method for fabricating Light-Emitting Device 1》 The light-emitting device 1 described in this example was fabricated using a method having the following steps.

[0381] [First Step] In the first step, electrode 101 was formed. Specifically, it was formed by a sputtering method using indium tin oxide (abbreviation: ITSO) containing silicon or silicon oxide as a target.

[0382] Note that electrode 101 contains ITSO and has a thickness of 70 nm and an area of 4 mm 2 (2 mm × 2 mm).

[0383] Next, the substrate on which electrode 101 was formed was washed with water, baked at 200 °C for 1 hour, and then subjected to UV ozone treatment for 370 seconds. After that, the substrate was introduced into a vacuum evaporation apparatus whose internal pressure was reduced to about 10 -4 Pa, and vacuum baking was performed at 170 °C for 30 minutes in the heating chamber of the vacuum evaporation apparatus. Then, the substrate was allowed to cool for about 30 minutes.

[0384] [Second step] In the second step, region 104A was formed on electrode 101. Specifically, after reducing the pressure inside the vacuum evaporation apparatus to 10 -4 Pa, the material was vapor-deposited using the resistance heating method.

[0385] Note that region 104A contains OCHD-001 and has a thickness of 1 nm.

[0386] [Third step] In the third step, region 104B was formed on region 104A. Specifically, the materials were co-evaporated using the resistance heating method.

[0387] Note that region 104B contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.10 and has a thickness of 10 nm.

[0388] [Fourth step] In the fourth step, region 112A was formed on region 104B. Specifically, the material was vapor-deposited using the resistance heating method.

[0389] Note that region 112A includes BBABnf and has a thickness of 20 nm.

[0390] [Fifth Step] In the fifth step, region 112B was formed on region 112A. Specifically, the material was vapor-deposited using a resistance heating method.

[0391] Note that region 112B includes 3,3’-(naphthalene-1,4-diyl)bis(9-phenyl-9H-carbazole) (abbreviation: PCzN2) and has a thickness of 10 nm.

[0392] [Sixth Step] In the sixth step, layer 111 was formed on region 112B. Specifically, the materials were co-vapor-deposited using a resistance heating method.

[0393] Note that layer 111 includes αN-βNPAnth and 3,10PCA2Nbf(IV)-02 at a weight ratio of αN-βNPAnth:3,10PCA2Nbf(IV)-02 = 1:0.015 and has a thickness of 25 nm.

[0394] [Seventh Step] In the seventh step, region 113A was formed on layer 111. Specifically, the materials were co-vapor-deposited using a resistance heating method.

[0395] Note that region 113A includes 2-{4-[9,10-di(naphthalen-2-yl)-2-anthryl]phenyl}-1-phenyl-1H-benzimidazole (abbreviation: ZADN) and Liq at a weight ratio of ZADN:Liq = 0.3:1 and has a thickness of 17.5 nm.

[0396] [Eighth Step] In the eighth step, region 113B was formed on region 113A. Specifically, the materials were co-vapor-deposited using a resistance heating method.

[0397] Note that region 113B contains ZADN and Liq at a ratio of ZADN:Liq = 1:0.3 (by weight) and has a thickness of 17.5 nm.

[0398] [Ninth Step] In the ninth step, electrode 102 was formed on region 113B. Specifically, a material was vapor-deposited using a resistive heating method.

[0399] Note that electrode 102 contains Al and has a thickness of 120 nm.

[0400] 《Operating Characteristics of Light-Emitting Device 1》 When power was supplied, light-emitting device 1 emitted light EL1 (see Fig. 15A). The operating characteristics of light-emitting device 1 were measured (see Figs. 16 to 22). Note that the measurements were carried out at room temperature.

[0401] When light-emitting device 1 was made to emit light at a luminance of about 1000 cd / m 2 Table 2 shows the main initial characteristics (Note that the initial characteristics of other light-emitting devices are also described in Table 2, and their configurations will be described later).

[0402]

Table 2

[0403] It was found that light-emitting device 1 exhibited good characteristics. For example, the voltage required to emit light at a luminance of 1000 cd / m 2 was lower than that of comparative light-emitting device 1A. Also, when light-emitting device 1 was continuously made to emit light at a constant current density of 50 mA / cm 2 , the decrease in luminance was less than that of comparative light-emitting device 1A (see Fig. 22). Specifically, the decrease in luminance was improved after about 525 hours. For example, at about 940 hours, the characteristic of decreasing to 92.1% of the initial luminance was improved to 93.6% of the initial luminance. As a result, it was possible to improve the reliability while suppressing the driving voltage. As a result, it was possible to provide a novel light-emitting device excellent in convenience, usefulness, or reliability.

[0404] Note that, unlike the comparative light-emitting device 1A, the light-emitting device 1 includes not only a region where the layer 104 contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.10, but also a region 104A that contains OCHD-001 at a high concentration.

[0405] <Light-emitting device 2> The configuration of the light-emitting device 2 is shown in Table 3. In the fabricated light-emitting device 2 described in this example, the concentration of the acceptor material AM contained in the region 104B is lower than that of the light-emitting device 1. Specifically, the region 104B of the light-emitting device 1 contains OCHD-001 at a concentration of 0.10 with respect to BBABnf, and the region 104B of the light-emitting device 2 contains OCHD-001 at a concentration of 0.03 with respect to BBABnf. Here, the different parts will be described in detail, and for the parts using the same configuration, the above description will be incorporated by reference.

[0406]

Table 3

[0407] 《Fabrication method of the light-emitting device 2》 The light-emitting device 2 was fabricated using a method having the following steps.

[0408] Note that the fabrication method of the light-emitting device 2 is different from that of the light-emitting device 1 in the step of forming the region 104B. Specifically, the co-evaporation of OCHD-001 so that the weight ratio becomes 0.03 with respect to BBABnf is different from the fabrication method of the light-emitting device 1. Here, the different parts will be described in detail, and for the parts using the same method, the above description will be incorporated by reference.

[0409] [Third step] In the third step, the region 104B was formed on the region 104A. Specifically, the materials were co-evaporated using the resistance heating method.

[0410] In addition, region 104B contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.03 and has a thickness of 10 nm.

[0411] 《Operating Characteristics of Light-Emitting Device 2》 The operating characteristics of light-emitting device 2 were measured (see FIGS. 23 to 29). The measurement was performed at room temperature.

[0412] When light-emitting device 2 was made to emit light at a luminance of about 1000 cd / m 2 ^2, the main initial characteristics are shown in Table 2.

[0413] Light-emitting device 2 was found to exhibit good characteristics. For example, the voltage required to emit light at a luminance of 1000 cd / m 2 ^2 was lower than that of comparative light-emitting device 1B. Also, when light-emitting device 2 was continuously made to emit light at a constant current density of 50 mA / cm 2 ^2, the decrease in luminance was less than that of comparative light-emitting device 1B (see FIG. 29). Specifically, the decrease in luminance was improved after about 610 hours. For example, at about 740 hours, the characteristic of decreasing to 94.4% of the initial luminance was improved to 95.3% of the initial luminance. As a result, it was possible to improve the reliability while suppressing the driving voltage. Consequently, it was possible to provide a novel light-emitting device excellent in convenience, usefulness, or reliability.

[0414] Note that, unlike comparative light-emitting device 1B, light-emitting device 2 includes not only the region of layer 104 that contains BBABnf and OCHD-001 but also region 104A that contains OCHD-001 at a high concentration. Further, region 104B of light-emitting device 2 contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.03, and layer 104 of comparative light-emitting device 1B contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.10.

[0415] <Light-Emitting Device 3> The configuration of the light-emitting device 3 is shown in Table 4. In the fabricated light-emitting device 3 described in this embodiment, the concentration of the acceptor material AM contained in region 104B is lower than that of the light-emitting device 2. Specifically, region 104B of the light-emitting device 2 contains OCHD-001 at a concentration of 0.03 with respect to BBABnf, and region 104B of the light-emitting device 3 contains OCHD-001 at a concentration of 0.01 with respect to BBABnf. Here, different parts will be described in detail, and for parts using the same configuration, the above description will be incorporated by reference.

[0416]

Table 4

[0417] 《Fabrication Method of Light-Emitting Device 3》 The light-emitting device 3 was fabricated using a method having the following steps.

[0418] Note that the fabrication method of the light-emitting device 3 is different from that of the light-emitting device 1 in the step of forming region 104B. Specifically, the co-evaporation of OCHD-001 so as to be 0.01 (weight ratio) with respect to BBABnf is different from the fabrication method of the light-emitting device 1. Here, different parts will be described in detail, and for parts using the same method, the above description will be incorporated by reference.

[0419] [Third Step] In the third step, region 104B was formed on region 104A. Specifically, the materials were co-evaporated using a resistance heating method.

[0420] Note that region 104B contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.01 and has a thickness of 10 nm.

[0421] 《Operating Characteristics of Light-Emitting Device 3》 The operating characteristics of the light-emitting device 3 were measured (see FIGS. 30 to 36). The measurement was performed at room temperature.

[0422] When the light-emitting device 3 emits light at a luminance of 1000 cd / m 2 Table 2 shows the main initial characteristics when the light-emitting device 3 emits light at such a luminance level.

[0423] The light-emitting device 3 was found to exhibit good characteristics. For example, the voltage required to emit light at a luminance of 1000 cd / m 2 was lower than that of the comparative light-emitting device 1B. Also, when the light-emitting device 3 was continuously made to emit light at a constant current density of 50 mA / cm 2 the decrease in luminance was less than that of the comparative light-emitting device 1B (see Fig. 36). Specifically, the decrease in luminance was improved after about 570 hours. For example, at about 740 hours, the characteristic of decreasing to 94.5% of the initial luminance was improved to 95.5% of the initial luminance. As a result, it was possible to improve the reliability while suppressing the driving voltage. Consequently, it was possible to provide a novel light-emitting device excellent in convenience, usefulness, or reliability.

[0424] Note that, unlike the comparative light-emitting device 1B, the light-emitting device 3 includes not only the region where layer 104 contains BBABnf and OCHD-001, but also a region 104A that contains OCHD-001 at a high concentration. Also, region 104B of the light-emitting device 3 contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.01, and layer 104 of the comparative light-emitting device 1B contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.10.

[0425] <Light-emitting device 4> The fabricated light-emitting device 4 described in this example has the same configuration as the light-emitting device 150 (see Fig. 15B). The light-emitting device 150 has an electrode 101, an electrode 102, a unit 103, a layer 104, and a unit 103(12), and the electrode 102 has a region that overlaps with the electrode 101. Also, the light-emitting device 150 includes a layer 105 and an intermediate layer 106, and the intermediate layer 106 includes a layer 104 and a layer 106A.

[0426] Unit 103 includes a region sandwiched between electrode 101 and electrode 102, and unit 103 includes layer 111 and layer 112.

[0427] Layer 111 includes a region sandwiching layer 112 between itself and electrode 101, and layer 111 contains a light-emitting material EM. In light-emitting device 4, bis[2-(2-pyridinyl-κN2)phenyl-κC][2-(5-phenyl-2-pyridinyl-κN2)phenyl-κC]iridium(III) (abbreviation: Ir(ppy)2(4dppy)) was used as the light-emitting material EM.

[0428] Layer 104 includes a region sandwiched between layer 112 and electrode 101, layer 104 contains an acceptor material AM and material HT1, and layer 104 includes region 104A and region 104B. In light-emitting device 4, OCHD-001 was used as the acceptor material AM. Also, PCBBiF was used as material HT1.

[0429] Region 104A includes a region sandwiched between region 104B and electrode 101, region 104A contains the acceptor material AM at concentration C1, and region 104B contains the acceptor material AM at concentration C2. Note that concentration C2 is higher than zero and lower than concentration C1. In light-emitting device 4, region 104A was formed using only OCHD-001, and 104B was formed using PCBBiF and OCHD-001.

[0430] 《Configuration of Light-Emitting Device 4》 The configuration of light-emitting device 4 is shown in Table 5. Also, the structural formulas of the materials used in the light-emitting device described in this example are shown below.

[0431]

Table 5

[0432]

Chemical Formula

[0433] "Method for Manufacturing Light-Emitting Device 4" A method having the following steps was used to manufacture the light-emitting device 4.

[0434] [First Step] In the first step, the electrode 101 was formed. Specifically, indium tin oxide (ITSO) containing silicon or silicon oxide was used as the target, and it was formed by sputtering.

[0435] Note that the electrode 101 contains ITSO, has a thickness of 70 nm, and an area of 4 mm 2 (2 mm × 2 mm).

[0436] Next, the substrate on which the electrode 101 was formed was washed with water, baked at 200 °C for 1 hour, and then subjected to UV ozone treatment for 370 seconds. After that, the substrate was introduced into a vacuum evaporation apparatus whose internal pressure was reduced to about 10 -4 Pa, and vacuum baking was performed at 170 °C for 30 minutes in the heating chamber of the vacuum evaporation apparatus. Then, the substrate was allowed to cool for about 30 minutes.

[0437] [Second Step] In the second step, layer 104(12) was formed on the electrode 101. Specifically, the material was vapor-deposited using the resistance heating method.

[0438] Note that layer 104(12) contains OCHD-001 and has a thickness of 1 nm.

[0439] [Third Step] In the third step, region 112A(12) was formed on layer 104(12). Specifically, the material was vapor-deposited using the resistance heating method.

[0440] Note that region 112A(12) contains BBABnf and has a thickness of 20 nm.

[0441] [Fourth Step] In the fourth step, region 112B(12) was formed on region 112A(12). Specifically, a material was vapor-deposited using a resistance heating method.

[0442] Note that region 112B(12) contains PCzN2 and has a thickness of 10 nm.

[0443] [Step 5] In the fifth step, layer 111(12) was formed on region 112B(12). Specifically, materials were co-vapor-deposited using a resistance heating method.

[0444] Note that layer 111(12) contains cgDBCzPA and 3,10PCA2Nbf(IV)-02 at a weight ratio of cgDBCzPA:3,10PCA2Nbf(IV)-02 = 1:0.015 and has a thickness of 25 nm.

[0445] [Step 6] In the sixth step, region 113A(12) was formed on layer 111(12). Specifically, a material was vapor-deposited using a resistance heating method.

[0446] Note that region 113A(12) contains cgDBCzPA and has a thickness of 10 nm.

[0447] [Step 7] In the seventh step, region 113B(12) was formed on region 113A(12). Specifically, a material was vapor-deposited using a resistance heating method.

[0448] Note that region 113B(12) contains 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen) and has a thickness of 10 nm.

[0449] [Step 8] In the eighth step, layer 105(12) was formed on region 113B(12). Specifically, a material was vapor-deposited using a resistance heating method.

[0450] Note that layer 105(12) contains lithium oxide (abbreviation: Li2O) and has a thickness of 0.1 nm.

[0451] [Step 9] In Step 9, layer 106A was formed on layer 105(12). Specifically, the material was vapor-deposited using the resistance heating method.

[0452] Note that layer 106A contains CuPc and has a thickness of 2 nm.

[0453] [Step 10] In Step 10, region 104A was formed on layer 106A. Specifically, the material was vapor-deposited using the resistance heating method.

[0454] Note that region 104A contains OCHD-001 and has a thickness of 1 nm.

[0455] [Step 11] In Step 11, region 104B was formed on region 104A. Specifically, the materials were co-vapor-deposited using the resistance heating method.

[0456] Note that region 104B contains PCBBiF and OCHD-001 at a weight ratio of PCBBiF:OCHD-001 = 1:0.1 and has a thickness of 10 nm.

[0457] [Step 12] In Step 12, layer 112 was formed on region 104B. Specifically, the material was vapor-deposited using the resistance heating method.

[0458] Note that layer 112 contains PCBBiF and has a thickness of 15 nm.

[0459] [Step 13] In Step 13, layer 111 was formed on layer 112. Specifically, the materials were co-vapor-deposited using the resistance heating method.

[0460] Layer 111 contains 8-(1,1'-biphenyl-4-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8BP-4mDBtPBfpm), 9-(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: βNCCP), and Ir(ppy)2(4dppy) at a weight ratio of 8BP-4mDBtPBfpm:βNCCP:Ir(ppy)2(4dppy) = 0.6:0.4:0.1 and has a thickness of 40 nm.

[0461] [Step 14] In Step 14, region 113A was formed on layer 111. Specifically, the material was vapor-deposited using the resistance heating method.

[0462] Region 113A contains 9,9'-(pyrimidine-4,6-diyl-di-3,1-phenylene)bis(9H-carbazole) (abbreviation: 4,6mCzP2Pm) and has a thickness of 20 nm.

[0463] [Step 15] In Step 15, region 113B was formed on region 113A. Specifically, the material was vapor-deposited using the resistance heating method.

[0464] Region 113B contains NBPhen and has a thickness of 15 nm.

[0465] [Step 16] In Step 16, layer 105 was formed on region 113B. Specifically, the material was vapor-deposited using the resistance heating method.

[0466] Layer 105 contains lithium fluoride (abbreviation: LiF) and has a thickness of 1 nm.

[0467] [Step 17] In Step 17, electrode 102 was formed on layer 105. Specifically, the material was vapor-deposited using the resistance heating method.

[0468] Note that the electrode 102 contains Al and has a thickness of 120 nm.

[0469] 《Operating Characteristics of Light-Emitting Device 4》 When power is supplied, the light-emitting device 4 emits light EL1 and light EL12 (see Fig. 15B). The operating characteristics of the light-emitting device 4 were measured (see Figs. 37 to 43). Note that the measurement was performed at room temperature.

[0470] The main initial characteristics of the light-emitting device 4 are shown in Table 2.

[0471] The light-emitting device 4 was found to exhibit good characteristics. For example, the voltage required to emit light at a luminance of 1000 cd / m 2 was lower than that of the comparative light-emitting device 2 and the comparative light-emitting device 3. Also, when the light-emitting device 4 was continuously made to emit light at a constant current density of 50 mA / cm 2 , the decrease in luminance was less than that of the comparative light-emitting device 2 (see Fig. 43). For example, at about 185 hours, the characteristic of decreasing to 90.2% of the initial luminance was improved to 92.6% of the initial luminance. As a result, the reliability could be improved while suppressing the driving voltage. As a result, a novel light-emitting device excellent in convenience, usefulness, or reliability could be provided.

[0472] Note that, unlike the comparative light-emitting device 2, the light-emitting device 4 includes not only a region where the layer 104 contains PCBBiF and OCHD-001 at a weight ratio of PCBBiF:OCHD-001 = 1:0.10, but also a region 104A that contains OCHD-001 at a high concentration. As a result, electrons can be supplied to the anode side and holes can be supplied to the cathode side at a low voltage. Also, unlike the comparative light-emitting device 3, the light-emitting device 4 includes not only a region where the layer 104 contains OCHD-001 at a high concentration, but also a region 104B that contains PCBBiF and OCHD-001 at a weight ratio of PCBBiF:OCHD-001 = 1:0.10. As a result, the thickness of the layer 104 can be increased. Alternatively, using the layer 104, the unevenness generated by laminating a plurality of layers can be covered. Alternatively, the non-uniformity generated at the interface due to the unevenness can be relaxed using the layer 104. Alternatively, an increase in the operating voltage caused by the non-uniformity of the interface can be prevented. Alternatively, electrons can be supplied to the anode side and holes can be supplied to the cathode side at a low voltage. Note that the total thickness of the region 104B of the light-emitting device 4 and the layer 112 is equal to the thickness of the layer 112 of the comparative light-emitting device 3.

[0473] <Light-emitting device 5> The fabricated light-emitting device 5 described in this embodiment has the same configuration as the light-emitting device 150 (see Fig. 44A). The light-emitting device 150 includes an electrode 101, an electrode 102, a unit 103(12), and a layer 104(12), and the electrode 102 has a region overlapping with the electrode 101. Also, the light-emitting device 150 includes a unit 103, an intermediate layer 106, and a layer 105.

[0474] The unit 103(12) has a region sandwiched between the electrode 101 and the electrode 102, and the unit 103(12) includes a layer 111(12) and a layer 112(12).

[0475] The layer 111(12) has a region sandwiching the layer 112(12) between itself and the electrode 101, and the layer 111(12) contains a light-emitting material EM. Note that in the light-emitting device 5, 3,10PCA2Nbf(IV)-02 was used as the light-emitting material EM.

[0476] Layer 104(12) includes a region sandwiched between layer 112(12) and electrode 101. Layer 104(12) contains an acceptor material AM and material HT1, and layer 104(12) includes region 104A(12) and region 104B(12). In light-emitting device 5, OCHD-001 was used for the acceptor material AM, and BBABnf was used for material HT1.

[0477] Region 104A(12) includes a region sandwiched between region 104B(12) and electrode 101. Region 104A(12) contains the acceptor material AM at concentration C1, and region 104B(12) contains the acceptor material AM at concentration C2. Note that concentration C2 is higher than zero and lower than concentration C1. In light-emitting device 5, region 104A(12) was formed using only OCHD-001, and region 104B(B) was formed using BBABnf and OCHD-001.

[0478] Unit 103 includes layer 113. Layer 113 includes region 113A and a sixth region 113B, and region 113A includes a region sandwiched between region 113B and layer 111.

[0479] Intermediate layer 106 includes a region sandwiched between unit 103(12) and unit 103.

[0480] 《Configuration of Light-Emitting Device 5》 The configuration of light-emitting device 5 is shown in Table 6. Also, the structural formula of the materials used in the light-emitting device described in this example is shown in Example 1.

[0481]

Table 6

[0482] 《Fabrication Method of Light-Emitting Device 5》 The light-emitting device 5 described in this example was fabricated using a method having the following steps.

[0483] [First Step] In the first step, a reflective film REF was formed. Specifically, it was formed by a sputtering method using an alloy (abbreviation: APC) containing silver (Ag), palladium (Pd), and copper (Cu) as a target.

[0484] Note that the reflective film REF contains APC and has a thickness of 100 nm.

[0485] [Second step] In the second step, an electrode 101 was formed on the reflective film REF. Specifically, it was formed by a sputtering method using ITSO.

[0486] Note that the electrode 101 contains ITSO, has a thickness of 85 nm, and an area of 4 mm 2 (2 mm × 2 mm).

[0487] Next, the substrate on which the electrode 101 was formed was washed with water, baked at 200 °C for 1 hour, and then subjected to UV ozone treatment for 370 seconds. Then, the substrate was introduced into a vacuum evaporation apparatus whose internal pressure was reduced to about 10 -4 Pa, and vacuum baking was performed at 170 °C for 30 minutes in the heating chamber of the vacuum evaporation apparatus. Then, the substrate was allowed to cool for about 30 minutes.

[0488] [Third step] In the third step, a region 104A(12) was formed on the electrode 101. Specifically, a material was deposited using a resistance heating method.

[0489] Note that the region 104A(12) contains OCHD - 001 and has a thickness of 1 nm.

[0490] [Fourth step] In the fourth step, a region 104B(12) was formed on the region 104A(12). Specifically, a material was co - deposited using a resistance heating method.

[0491] Note that region 104B(12) contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.03 and has a thickness of 10 nm.

[0492] [Fifth step] In the fifth step, region 112A(12) was formed on region 104B(12). Specifically, the material was vapor-deposited using the resistance heating method.

[0493] Note that region 112A(12) contains BBABnf and has a thickness of 45 nm.

[0494] [Sixth step] In the sixth step, region 112B(12) was formed on region 112A(12). Specifically, the material was vapor-deposited using the resistance heating method.

[0495] Note that region 112B(12) contains PCzN2 and has a thickness of 10 nm.

[0496] [Seventh step] In the seventh step, layer 111(12) was formed on region 112B(12). Specifically, the materials were co-vapor-deposited using the resistance heating method.

[0497] Note that layer 111(12) contains αN-βNPAnth and 3,10PCA2Nbf(IV)-02 at a weight ratio of αN-βNPAnth:3,10PCA2Nbf(IV)-02 = 1:0.015 and has a thickness of 25 nm.

[0498] [Eighth step] In the eighth step, region 113A(12) was formed on layer 111(12). Specifically, the material was vapor-deposited using the resistance heating method.

[0499] Note that region 113A(12) contains 2mDBTBPDBq-II and has a thickness of 15 nm.

[0500] [Ninth step] In the 9th step, region 113B(12) was formed on region 113A(12). Specifically, a material was vapor-deposited using a resistance heating method.

[0501] Note that region 113B(12) contains NBPhen and has a thickness of 10 nm.

[0502] [10th step] In the 10th step, layer 105(12) was formed on region 113B(12). Specifically, a material was vapor-deposited using a resistance heating method.

[0503] Note that layer 105(12) contains Li2O and has a thickness of 0.05 nm.

[0504] [11th step] In the 11th step, layer 106A was formed on layer 105(12). Specifically, a material was vapor-deposited using a resistance heating method.

[0505] Note that layer 106A contains CuPc and has a thickness of 2 nm.

[0506] [12th step] In the 12th step, layer 104 was formed on layer 106A. Specifically, a material was vapor-deposited using a resistance heating method.

[0507] Note that layer 104 contains OCHD-001 and has a thickness of 2.5 nm.

[0508] [13th step] In the 13th step, layer 112 was formed on layer 104. Specifically, a material was vapor-deposited using a resistance heating method.

[0509] Note that layer 112 contains PCBBiF and has a thickness of 25 nm.

[0510] [14th step] In the 14th step, layer 111 was formed on layer 112. Specifically, the materials were co-evaporated using a resistive heating method.

[0511] Note that layer 111 contains 8BP-4mDBtPBfpm, βNCCP, and Ir(ppy)2(4dppy) at a weight ratio of 8BP-4mDBtPBfpm:βNCCP:Ir(ppy)2(4dppy) = 0.5:0.5:0.1 and has a thickness of 40 nm.

[0512] [15th step] In the 15th step, region 113A was formed on layer 111. Specifically, the materials were evaporated using a resistive heating method.

[0513] Note that region 113A contains 4,6mCzP2Pm and has a thickness of 25 nm.

[0514] [16th step] In the 16th step, region 113B was formed on region 113A. Specifically, the materials were evaporated using a resistive heating method.

[0515] Note that region 113B contains NBPhen and has a thickness of 15 nm.

[0516] [17th step] In the 17th step, layer 105 was formed on region 113B. Specifically, the materials were evaporated using a resistive heating method.

[0517] Note that layer 105 contains LiF and has a thickness of 1 nm.

[0518] [18th step] In the 18th step, electrode 102A was formed on layer 105. Specifically, the materials were co-evaporated using a resistive heating method.

[0519] Note that electrode 102A contains Ag and Mg at a volume ratio of Ag:Mg = 1:0.1 and has a thickness of 15 nm.

[0520] [Step 19] In Step 19, electrode 102B was formed on electrode 102A. Specifically, it was formed by a sputtering method using indium tin oxide (abbreviation: ITO) as a target.

[0521] Note that electrode 102B contains ITO and has a thickness of 70 nm.

[0522] 《Operating Characteristics of Light-Emitting Device 5》 When power was supplied, light-emitting device 5 emitted light EL1 and light EL12 (see Fig. 44A). The operating characteristics of light-emitting device 5 were measured (see Figs. 45 to 51). Note that the measurement was performed at room temperature. Also, the light transmitted through the blue color layer was measured. Thereby, the blue light contained in the light emitted by light-emitting device 5 was measured. Specifically, mainly light EL12 was measured (see Fig. 44A).

[0523] The main initial characteristics of light-emitting device 5 are shown in Table 2.

[0524] Light-emitting device 5 was found to exhibit good characteristics. For example, the voltage required to emit light at a luminance of 1000 cd / m 2 was lower than that of comparative light-emitting device 4. Also, when light-emitting device 5 was continuously made to emit light at a constant current density of 50 mA / cm 2 , the decrease in luminance was less than that of comparative light-emitting device 4 (see Fig. 51). Thereby, the reliability could be improved while suppressing the driving voltage. As a result, a novel light-emitting device excellent in convenience, usefulness, or reliability could be provided.

[0525] Note that, unlike the comparative light-emitting device 4, the light-emitting device 5 includes not only a region where the layer 104(12) contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.03, but also a region 104A(12) that contains OCHD-001 at a high concentration. As a result, holes can be supplied to the unit 103(12) at a low voltage. Also, unlike the comparative light-emitting device 4, the light-emitting device 5 includes not only a region where the layer 104(12) contains OCHD-001 at a high concentration, but also a region 104B(12) that contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.03. As a result, the thickness of the layer 104(12) can be increased. Alternatively, using the layer 104(12), the unevenness generated on the electrode 101 can be covered. Alternatively, the non-uniformity generated at the interface due to the unevenness can be alleviated using the layer 104(12).

[0526] (Reference Example 1) The configuration of the comparative light-emitting device 1 is shown in Table 7.

[0527] In the fabricated comparative light-emitting device 1 described in this example, the layer 104 contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.10.

[0528] [Table 7]

[0529] 《Fabrication Method of Comparative Light-Emitting Device 1》 The comparative light-emitting device 1A and the comparative light-emitting device 1B were fabricated using a method having the following steps. Note that the comparative light-emitting device 1A and the comparative light-emitting device 1B were fabricated to have the same configuration.

[0530] Note that the manufacturing method of the comparative light-emitting device 1 is different from the manufacturing methods of the light-emitting devices 1 to 3 in that, in the step of forming the layer 104, a region containing OCHD-001 at a high concentration is not formed, and only BBABnf and OCHD-001 are co-evaporated so that BBABnf:OCHD-001 = 1:0.10 (weight ratio). Therefore, the second step is omitted, and after the first step, the process proceeds to the third step. Here, the different parts will be described in detail, and for the parts using the same method, the above description will be incorporated by reference.

[0531] [Third step] In the third step, the layer 104 was formed on the electrode 101. Specifically, the materials were co-evaporated using the resistance heating method.

[0532] Note that the layer 104 contains BBABnf and OCHD-001 at a ratio of BBABnf:OCHD-001 = 1:0.10 (weight ratio) and has a thickness of 10 nm.

[0533] 《Operating characteristics of the comparative light-emitting device 1》 The operating characteristics of the comparative light-emitting device 1A and the comparative light-emitting device 1B were measured. The measurements were performed at room temperature.

[0534] The main initial characteristics of the comparative light-emitting device 1A and the comparative light-emitting device 1B are shown in Table 2.

[0535] (Reference Example 2) The configuration of the comparative light-emitting device 2 is shown in Table 8.

[0536] The fabricated comparative light-emitting device 2 described in this example has a layer 104 containing PCBBiF and OCHD-001 at a ratio of PCBBiF:OCHD-001 = 1:0.10 (weight ratio).

[0537]

Table 8

[0538] 《Manufacturing method of the comparative light-emitting device 2》 The comparative light-emitting device 2 was fabricated using a method having the following steps.

[0539] Note that the method for fabricating the comparative light-emitting device 2 is different from the method for fabricating the light-emitting device 4 in that, in the step of forming the layer 104, no region containing OCHD-001 at a high concentration is formed, and only PCBBiF and OCHD-001 are co-evaporated so that PCBBiF:OCHD-001 = 1:0.10 (weight ratio). Therefore, the tenth step is omitted, and after the ninth step, the process proceeds to the eleventh step. Here, the different parts will be described in detail, and for the parts using the same method, the above description will be incorporated by reference.

[0540] [Eleventh Step] In the eleventh step, the layer 104 was formed on the layer 106A. Specifically, the materials were co-evaporated using the resistance heating method.

[0541] Note that the layer 104 contains PCBBiF and OCHD-001 at a ratio of PCBBiF:OCHD-001 = 1:0.10 (weight ratio) and has a thickness of 10 nm.

[0542] 《Operating Characteristics of Comparative Light-Emitting Device 2》 The operating characteristics of the comparative light-emitting device 2 were measured. The measurement was performed at room temperature.

[0543] The main initial characteristics of the comparative light-emitting device 2 are shown in Table 2.

[0544] (Reference Example 3) The configuration of the comparative light-emitting device 3 is shown in Table 9.

[0545] In the fabricated comparative light-emitting device 3 described in this example, the layer 104 contains OCHD-001 at a high concentration.

[0546]

Table 9

[0547] "Method for Fabricating Comparative Luminescence Device 3" The comparative luminescence device 3 was fabricated using a method having the following steps.

[0548] Note that the method for fabricating the comparative luminescence device 3 differs from the method for fabricating the luminescence device 4 in that in the step of forming the layer 104, a region containing OCHD-001 at a high concentration is not formed, and only PCBBiF and OCHD-001 are co-evaporated so that PCBBiF:OCHD-001 = 1:0.10 (weight ratio). Therefore, the 11th step is omitted, and following the 10th step, the process proceeds to the 12th step. Here, the different parts will be described in detail, and for the parts using the same method, the above description will be incorporated by reference.

[0549] [Step 10] In the 10th step, the layer 104 was formed on the layer 106A. Specifically, the material was vapor-deposited using the resistance heating method.

[0550] Note that the layer 104 contains OCHD-001 at a high concentration and has a thickness of 1 nm.

[0551] [Step 12] In the 12th step, the layer 112 was formed on the layer 104. Specifically, the material was vapor-deposited using the resistance heating method.

[0552] Note that the layer 112 contains PCBBiF and has a thickness of 25 nm.

[0553] "Operating Characteristics of Comparative Luminescence Device 3" The operating characteristics of the comparative luminescence device 3 were measured. The measurement was performed at room temperature.

[0554] The main initial characteristics of the comparative luminescence device 3 are shown in Table 2.

[0555] (Reference Example 4) The configuration of the comparative luminescence device 4 is shown in Table 10.

[0556] In the fabricated comparative light-emitting device 4 described in this embodiment, layer 104(12) contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.03.

[0557]

Table 10

[0558] 《Fabrication Method of Comparative Light-Emitting Device 4》 The comparative light-emitting device 4 was fabricated using a method having the following steps.

[0559] Note that the fabrication method of the comparative light-emitting device 4 is different from that of the light-emitting device 5 in that in the step of forming layer 104(12), a region containing OCHD-001 at a high concentration is not formed, and only co-evaporation is performed so that BBABnf and OCHD-001 have a weight ratio of BBABnf:OCHD-001 = 1:0.03. Therefore, the third step is omitted, and the process proceeds to the fourth step following the second step. Here, the different parts will be described in detail, and for the parts using the same method, the above description will be incorporated by reference.

[0560] [Fourth Step] In the fourth step, layer 104(12) was formed on electrode 101. Specifically, the materials were co-evaporated using the resistance heating method.

[0561] Note that layer 104(12) contains BBABnf and OCHD-001 at a weight ratio of BBABnf:OCHD-001 = 1:0.03 and has a thickness of 10 nm.

[0562] 《Operating Characteristics of Comparative Light-Emitting Device 4》 The operating characteristics of the comparative light-emitting device 4 were measured. Note that the measurement was performed at room temperature. Also, the light transmitted through the blue coloring layer was measured. Thereby, the blue light contained in the light emitted by the comparative light-emitting device 4 was measured.

[0563] Table 2 shows the main initial characteristics of the comparative light-emitting device 4.

[0564] Note that this embodiment can be appropriately combined with other embodiments shown in this specification.

[0565] For example, in this specification and the like, when it is explicitly described that X and Y are connected, it is disclosed in this specification and the like that X and Y are electrically connected, X and Y are functionally connected, and X and Y are directly connected. Therefore, it is not limited to a predetermined connection relationship, for example, the connection relationship shown in the figure or the text, and those other than the connection relationship shown in the figure or the text are also disclosed in the figure or the text.

[0566] Here, it is assumed that X and Y are objects (for example, devices, elements, circuits, wirings, electrodes, terminals, conductive films, layers, etc.).

[0567] As an example of the case where X and Y are directly connected, it is the case where an element (for example, a switch, a transistor, a capacitor element, an inductor, a resistor element, a diode, a display element, a light-emitting element, a load, etc.) that enables electrical connection between X and Y is not connected between X and Y, and X and Y are connected without passing through an element (for example, a switch, a transistor, a capacitor element, an inductor, a resistor element, a diode, a display element, a light-emitting element, a load, etc.) that enables electrical connection between X and Y.

[0568] As an example of the case where X and Y are electrically connected, one or more elements that enable electrical connection between X and Y (for example, a switch, transistor, capacitor, inductor, resistor, diode, display element, light-emitting element, load, etc.) can be connected between X and Y. Note that the switch has a function of controlling on / off. That is, the switch can be in a conductive state (on state) or a non-conductive state (off state), and has a function of controlling whether to allow current to flow or not. Or, the switch has a function of selecting and switching the path through which current flows. Note that when X and Y are electrically connected, it includes the case where X and Y are directly connected.

[0569] As an example of the case where X and Y are functionally connected, one or more circuits that enable functional connection between X and Y (for example, a logic circuit (inverter, NAND circuit, NOR circuit, etc.), a signal conversion circuit (DA conversion circuit, AD conversion circuit, gamma correction circuit, etc.), a potential level conversion circuit (power supply circuit (boost circuit, buck circuit, etc.), level shifter circuit for changing the potential level of a signal, etc.), a voltage source, a current source, a switching circuit, an amplifier circuit (circuit that can increase signal amplitude or current amount, operational amplifier, differential amplifier circuit, source follower circuit, buffer circuit, etc.), a signal generation circuit, a memory circuit, a control circuit, etc.) can be connected between X and Y. Note that as an example, even if another circuit is interposed between X and Y, when the signal output from X is transmitted to Y, X and Y are considered to be functionally connected. Note that when X and Y are functionally connected, it includes the case where X and Y are directly connected and the case where X and Y are electrically connected.

[0570] In addition, when it is explicitly described that X and Y are electrically connected, the cases where X and Y are electrically connected (i.e., when they are connected with another element or another circuit interposed therebetween), the cases where X and Y are functionally connected (i.e., when they are functionally connected with another circuit interposed therebetween), and the cases where X and Y are directly connected (i.e., when they are connected without another element or another circuit interposed therebetween) shall be those disclosed in this specification and the like. That is, when it is explicitly described that X and Y are electrically connected, it is assumed that the same content as when it is only explicitly described that they are connected is disclosed in this specification and the like.

[0571] In addition, for example, when the source (or the first terminal, etc.) of a transistor is electrically connected to X via (or without) Z1, and the drain (or the second terminal, etc.) of the transistor is electrically connected to Y via (or without) Z2, or when the source (or the first terminal, etc.) of the transistor is directly connected to a part of Z1, another part of Z1 is directly connected to X, the drain (or the second terminal, etc.) of the transistor is directly connected to a part of Z2, and another part of Z2 is directly connected to Y, it can be expressed as follows.

[0572] For example, it can be expressed as "X, the source (or the first terminal, etc.) of the transistor, and the drain (or the second terminal, etc.) of the transistor are electrically connected to each other, and they are electrically connected in the order of X, the source (or the first terminal, etc.) of the transistor, the drain (or the second terminal, etc.) of the transistor, and Y." Or, it can be expressed as "The source (or the first terminal, etc.) of the transistor is electrically connected to X, the drain (or the second terminal, etc.) of the transistor is electrically connected to Y, and X, the source (or the first terminal, etc.) of the transistor, the drain (or the second terminal, etc.) of the transistor, and Y are electrically connected in this order." Or, it can be expressed as "X is electrically connected to Y via the source (or the first terminal, etc.) and the drain (or the second terminal, etc.) of the transistor, and X, the source (or the first terminal, etc.) of the transistor, the drain (or the second terminal, etc.) of the transistor, and Y are provided in this connection order." By using an expression method similar to these examples to define the connection order in the circuit configuration, the source (or the first terminal, etc.) of the transistor and the drain (or the second terminal, etc.) of the transistor can be distinguished to determine the technical scope.

[0573] Alternatively, as another way of expression, for example, it can be expressed as "The source (or the first terminal, etc.) of the transistor is electrically connected to X via at least the first connection path, the first connection path does not have the second connection path, the second connection path is the path between the source (or the first terminal, etc.) of the transistor and the drain (or the second terminal, etc.) of the transistor via the transistor, the first connection path is the path via Z1, the drain (or the second terminal, etc.) of the transistor is electrically connected to Y via at least the third connection path, the third connection path does not have the second connection path, and the third connection path is the path via Z2." Or it can be expressed as "The source (or the first terminal, etc.) of the transistor is electrically connected to X via Z1 by at least the first connection path, the first connection path does not have the second connection path, the second connection path has a connection path via the transistor, the drain (or the second terminal, etc.) of the transistor is electrically connected to Y via Z2 by at least the third connection path, and the third connection path does not have the second connection path." Or it can be expressed as "The source (or the first terminal, etc.) of the transistor is electrically connected to X via Z1 by at least the first electrical path, the first electrical path does not have the second electrical path, the second electrical path is the electrical path from the source (or the first terminal, etc.) of the transistor to the drain (or the second terminal, etc.) of the transistor, the drain (or the second terminal, etc.) of the transistor is electrically connected to Y via Z2 by at least the third electrical path, the third electrical path does not have the fourth electrical path, and the fourth electrical path is the electrical path from the drain (or the second terminal, etc.) of the transistor to the source (or the first terminal, etc.) of the transistor." By defining the connection paths in the circuit configuration using an expression method similar to these examples, it is possible to distinguish between the source (or the first terminal, etc.) and the drain (or the second terminal, etc.) of the transistor and determine the technical scope.

[0574] Note that these expression methods are just examples and are not limited to these expression methods. Here, X, Y, Z1, and Z2 are assumed to be objects (for example, devices, elements, circuits, wirings, electrodes, terminals, conductive films, layers, etc.).

[0575] Note that even when components that are independent on a circuit diagram are shown as being electrically connected, there may be a case where one component has the functions of multiple components. For example, when a part of a wiring also functions as an electrode, one conductive film has the functions of both a wiring component and an electrode component. Therefore, the electrically connected in this specification includes such a case where one conductive film has the functions of multiple components within its scope.

Explanation of Reference Signs

[0576] HOMO1: First HOMO level, HOMO2: Second HOMO level, LUMO1: First LUMO level, LUMO2: Second LUMO level, 101: Electrode, 102: Electrode, 102A: Electrode, 102B: Electrode, 103: Unit, 104: Layer, 104A: Region, 104B: Region, 104(12): Layer, 105: Layer, 106: Intermediate layer, 106A: Layer, 106B: Layer, 111: Layer, 112: Layer, 112A: Region, 112B: Region, 113: Layer, 113A: Region, 113B: Region, 150: Light-emitting device, 400: Substrate, 401: First electrode, 403: EL layer, 404: Second electrode, 405: Sealing material, 406: Sealing material, 407: Sealing substrate, 412: Pad, 420: IC chip, 601: Source line driving circuit, 602: Pixel portion, 603: Gate line driving circuit, 604: Sealing substrate, 605: Sealing material, 607: Space, 608: Wiring, 610: Element substrate, 611: Switching FET, 612: Current control FET, 613: First electrode, 614: Insulator, 616: EL layer, 617: Second electrode, 618: Light-emitting device, 623: FET, 700: Light-emitting panel, 951: Substrate, 952: Electrode, 953: Insulating layer, 954: Partition layer, 955: EL layer, 956: Electrode, 1001: Substrate, 1002: Underlying insulating film, 1003: Gate insulating film, 1006: Gate electrode, 1007: Gate electrode, 1008: Gate electrode, 1020: First interlayer insulating film, 1021: Second interlayer insulating film, 1022: Electrode, 1024B: First electrode, 1024G: First electrode, 1024R: First electrode, 1024W: First electrode, 1025: Partition, 1028: EL layer, 1029: Second electrode, 1031: Sealing substrate, 1032: Sealing material, 1033: Base material, 1034B: Colored layer, 1034G: Colored layer, 1034R: Colored layer, 1035: Black matrix, 1036: Overcoat layer, 1037: Third interlayer insulating film, 1040: Pixel portion, 1041: Driving circuit portion, 1042: Peripheral portion, 2001: Housing, 2002: Light source, 2100: Robot, 2101: Illuminance sensor, 2102: Microphone, 2103: Upper camera, 2104: Speaker, 2105: Display, 2106: Lower camera, 2107: Obstacle sensor, 2108: Moving mechanism, 2110: Arithmetic unit, 3001: Lighting device, 5000: Housing, 5001: Display portion, 5002: Display portion, 5003: Speaker,5004: LED lamp, 5006: Connection terminal, 5007: Sensor, 5008: Microphone, 5012: Support part, 5013: Earphone, 5100: Cleaning robot, 5101: Display, 5102: Camera, 5103: Brush, 5104: Operation button, 5120: Dust, 5140: Portable electronic device, 5200: Display area, 5201: Display area, 5202: Display area, 5203: Display area, 7101: Housing, 7103: Display unit, 7105: Stand, 7107: Display unit, 7109: Operation key, 7110: Remote control operation unit, 7201: Main body, 7202: Housing, 7203: Display unit, 7204: Keyboard, 7205: External connection port, 7206: Pointing device, 7210: Second display unit, 7401: Housing, 7402: Display unit, 7403: Operation button, 7404: External connection port, 7405: Speaker, 7406: Microphone, 9310: Portable information terminal, 9311: Display panel, 9313: Hinge, 9315: Housing,

Claims

1. It has a first electrode, a second electrode, a first unit, a second unit, and an intermediate layer, The first unit is located between the first electrode and the intermediate layer, The intermediate layer is located between the first unit and the second unit, The second unit is located between the intermediate layer and the second electrode, The intermediate layer has a first layer and a second layer, The first layer is located between the first unit and the second layer, The second layer is located between the first layer and the second unit, The first unit has a first light-emitting layer, The second unit has a second light-emitting layer, a third layer, and a fourth layer, The third layer is located between the second layer and the second light-emitting layer, The second light-emitting layer is located between the third layer and the fourth layer, The fourth layer is located between the second light-emitting layer and the second electrode, The first layer has a first material, The second layer has a first compound having a halogen group or a cyano group and a second material, The third layer has a third material, The fourth layer has a fourth material, The second layer has a first region and a second region, The first region is located between the first layer and the second region, The first region contains the first compound at a first concentration, The second region contains the first compound at a second concentration, The second concentration is higher than zero and lower than the first concentration, a light-emitting device.

2. It has a first electrode, a second electrode, a first unit, a second unit, and an intermediate layer, The first unit is located between the first electrode and the intermediate layer, The intermediate layer is located between the first unit and the second unit, The second unit is located between the intermediate layer and the second electrode, The intermediate layer has a first layer and a second layer, The first layer is located between the first unit and the second layer, The second layer is located between the first layer and the second unit, The first unit has a first light-emitting layer, The second unit has a second light-emitting layer, a third layer, and a fourth layer, The third layer is located between the second layer and the second light-emitting layer, The second light-emitting layer is located between the third layer and the fourth layer, The fourth layer is located between the second light-emitting layer and the second electrode, The first layer has a first material, The second layer has a first compound having a halogen group or a cyano group and a second material, The second layer has a first region and a second region, The first region is located between the first layer and the second region, The first region contains the first compound at a first concentration, The second region contains the first compound at a second concentration, The second concentration is higher than zero and lower than the first concentration, The third layer has a third region and a fourth region, The third region is located between the second layer and the fourth region, The fourth region is located between the third region and the second light-emitting layer, The fourth region has a third material, The fourth layer has a fourth material, The HOMO level of the first material is -5.7 eV or more and -5.4 eV or less, The HOMO level of the third material is in the range of -0.2 eV or more and 0 eV or less with respect to the HOMO level of the first material, a light-emitting device.

3. It has a first electrode, a second electrode, a first unit, a second unit, and an intermediate layer, The first unit is located between the first electrode and the intermediate layer, The intermediate layer is located between the first unit and the second unit, The second unit is located between the intermediate layer and the second electrode, The intermediate layer has a first layer and a second layer, The first layer is located between the first unit and the second layer, The second layer is located between the first layer and the second unit, The first unit has a first light-emitting layer, The second unit has a second light-emitting layer, a third layer, and a fourth layer, The third layer is located between the second layer and the second light-emitting layer, The second light-emitting layer is located between the third layer and the fourth layer, The fourth layer is located between the second light-emitting layer and the second electrode, The first layer has a first material, The second layer has a first compound having a halogen group or a cyano group and a second material, The second layer has a first region and a second region, The first region is located between the first layer and the second region, The first region contains the first compound at a first concentration, The second region contains the first compound at a second concentration, wherein the second concentration is higher than zero and lower than the first concentration, the third layer has a third region and a fourth region, the third region is located between the second layer and the fourth region, the fourth region is located between the third region and the second light-emitting layer, the fourth region has a third material, the HOMO level of the first material is not less than -5.7 eV and not more than -5.4 eV, the HOMO level of the third material is in the range of not less than -0.2 eV and not more than 0 eV with respect to the HOMO level of the first material, the fourth layer has a fifth region and a sixth region, the fifth region is located between the second light-emitting layer and the sixth region, the fifth region has a fifth material, the sixth region has a fourth material, the second light-emitting layer has a light-emitting material and a sixth material, a light-emitting device, wherein the LUMO level of the fifth material is in the range of not less than -0.4 eV and not more than -0.1 eV with respect to the LUMO level of the sixth material.

4. The light-emitting device according to any one of claims 1 to 3, wherein the fourth material is an organic complex of an alkali metal or an organic complex of an alkaline earth metal.

5. The light-emitting device according to any one of claims 1 to 4, wherein the first region has only the first compound.

6. A light-emitting device having the light-emitting device according to any one of claims 1 to 5 and a transistor.

7. An electronic device having the light-emitting device according to claim 6 and a sensor, an operation button, a speaker, or a microphone.

Images