Light emitting device

Abstract

A light emitting device having good characteristics is provided. One embodiment of the present invention is a light emitting device including a first electrode, a second electrode, and an organic compound layer between the first electrode and the second electrode, the organic compound layer including at least a light emitting layer and an electron injection layer, the electron injection layer contains a first organic compound including a phenanthroline skeleton having an electron-donating group, the first organic compound having a water solubility in pure water of 20 mg / L or less and a glass transition temperature of 80 DEG C or more, and the outline of the light-emitting layer substantially coincides with the outline of the electron injection layer in plan view.

Description

Technical Field

[0001] One aspect of the present invention relates to a light-emitting device.

[0002] Note that one aspect of the present invention is not limited to the above technical field. As an example of the technical field of one aspect of the present invention, semiconductor devices, display devices, light-emitting devices, power storage devices, storage devices, electronic devices, lighting devices, input devices (e.g., touch sensors), input / output devices (e.g., touch panels), and driving methods or manufacturing methods of the above devices can be cited. Background Art

[0003] In recent years, display devices have been applied to various uses. For example, as uses of large display devices, research and development have been carried out on home television devices (also referred to as TVs or television receivers), digital signage, and public information displays (PIDs: Public Information Display), etc. As uses of small display devices, research and development have been carried out on smartphones or tablet terminals equipped with touch panels, etc.

[0004] At the same time, high definition of display devices is also being carried out. As devices that require high-definition display devices, for example, research and development have been carried out on devices for virtual reality (VR: Virtual Reality), augmented reality (AR: Augmented Reality), substitutional reality (SR: Substitutional Reality), and mixed reality (MR: Mixed Reality).

[0005] As a display element for display devices, the development of light-emitting devices (also referred to as light-emitting elements) has been increasingly active. Light-emitting devices (also referred to as EL devices, EL elements) that utilize the electroluminescence (hereinafter referred to as EL) phenomenon, especially organic EL devices mainly using organic compounds, have the following characteristics: it is easy to achieve thinness and light weight; it can respond to input signals at high speed; and it can be driven using a DC constant voltage power supply, etc. Therefore, it is preferably applied to display devices.

[0006] In order to obtain a higher-definition light-emitting device using an organic EL device, a technique of patterning an organic layer by using a photolithography method using a photoresist or the like instead of an evaporation method using a metal mask has been studied. By using the photolithography method, a high-definition display device with an interval of several μm in the EL layer can be obtained (for example, refer to Patent Document 1).

[0007] [Patent Document 1] Japanese PCT International Application Translation No. 2018-521459 Gazette Summary of the Invention

[0008] In known organic EL devices (also referred to as light-emitting devices in this specification), the initial characteristics and reliability of the EL layer are affected when exposed to atmospheric components such as water and oxygen. In common practice steps, the EL layer is processed in an atmosphere close to vacuum. In particular, the electron injection layer uses an alkali metal, an alkaline earth metal, or a compound thereof, and these metals and compounds have a very high reactivity with water or oxygen. When the surface of the EL layer is exposed to the atmosphere, the electron injection layer rapidly deteriorates and loses its function as an electron injection layer.

[0009] However, in the above-described process of processing by photolithography, it is inevitable to expose the surface of the EL layer to the atmosphere.

[0010] One of the objects of one aspect of the present invention is to provide a novel light-emitting device. Another object of one aspect of the present invention is to provide a light-emitting device having good efficiency. Another object of one aspect of the present invention is to provide a light-emitting device having good reliability. Another object of one aspect of the present invention is to provide a light-emitting device having good efficiency and reliability.

[0011] Another object of one aspect of the present invention is to provide a novel light-emitting device manufactured through a photolithography process. Another object of one aspect of the present invention is to provide a light-emitting device having good efficiency manufactured through a photolithography process. Another object of one aspect of the present invention is to provide a light-emitting device having good reliability manufactured through a photolithography process. Another object of one aspect of the present invention is to provide a light-emitting device having good luminous efficiency and reliability manufactured through a photolithography process.

[0012] Another object of one aspect of the present invention is to provide a novel light-emitting device that can be used in a high-definition display device. Another object of one aspect of the present invention is to provide a light-emitting device having good efficiency that can be used in a high-definition display device. Another object of one aspect of the present invention is to provide a light-emitting device having good reliability that can be used in a high-definition display device. Another object of one aspect of the present invention is to provide a light-emitting device having good luminous efficiency and reliability that can be used in a high-definition display device.

[0013] Another object of one aspect of the present invention is to provide a display device with high reliability. Another object of one aspect of the present invention is to provide a high-definition display device. Another object of one aspect of the present invention is to provide a high-definition and highly reliable display device.

[0014] Note that the description of these objects does not preclude the existence of other objects. One embodiment of the present invention does not need to achieve all of the above objects. Objects other than the above objects can be extracted from the descriptions in the specification, the drawings, and the claims.

[0015] One embodiment of the present invention is a light-emitting device including a first electrode, a second electrode, and an organic compound layer disposed between the first electrode and the second electrode. The organic compound layer includes at least a light-emitting layer and an electron injection layer. The electron injection layer contains a first organic compound including a phenanthroline skeleton having an electron-donating group. The water solubility of the first organic compound in pure water is 20 mg / L or less, and the glass transition temperature is 80°C or higher. In a plan view, the outline of the light-emitting layer substantially coincides with the outline of the electron injection layer. One embodiment of the present invention is a light-emitting device including a first electrode, a second electrode, and an organic compound layer disposed between the first electrode and the second electrode. The organic compound layer includes at least a light-emitting layer and an electron injection layer in contact with the second electrode. The electron injection layer contains a first organic compound including a phenanthroline skeleton having an electron-donating group. The first organic compound interacts with the second electrode. The water solubility of the first organic compound in pure water is 20 mg / L or less, and the glass transition temperature is 80°C or higher. In a plan view, the outline of the light-emitting layer substantially coincides with the outline of the electron injection layer.

[0017] In the above light-emitting device, the phenanthroline skeleton is a 1,10-phenanthroline skeleton and has an electron-donating group at at least one of the 4-position and the 7-position.

[0018] In the above light-emitting device, the electron-donating group is at least one of an alkyl group, an alkoxy group, an aryloxy group, an alkylamino group, an arylamino group, and a heterocyclic amino group.

[0019] In the above light-emitting device, the water solubility of the first organic compound in pure water is 0.1 mg / L or more and 10 mg / L or less.

[0020] In the above light-emitting device, the glass transition temperature of the first organic compound is 100°C or higher.

[0021] In the above light-emitting device, when the threshold value of the electron density distribution in atomic units is 0.0004 e / a0 3 the minimum value of the electrostatic potential of the first organic compound is -0.085 E h or less.

[0022] In the above light-emitting device, the acidity coefficient pKa of the first organic compound is 8 or higher.

[0023] One embodiment of the present invention is a light-emitting device including a first electrode, a second electrode, and an organic compound layer disposed between the first electrode and the second electrode. The organic compound layer includes at least a light-emitting layer and an electron injection layer in contact with the second electrode. The electron injection layer contains a first organic compound represented by Structural Formula (100). In a plan view, the outline of the light-emitting layer substantially coincides with the outline of the electron injection layer.

[0024] [Chemical Formula 1]

[0025] In the above light-emitting device, the organic compound layer includes an electron transport layer between the light-emitting layer and the electron injection layer. The electron transport layer contains a second organic compound having a π-deficient heteroaromatic ring. The LUMO energy level of the first organic compound is higher than the LUMO energy level of the second organic compound.

[0026] In the above light-emitting device, the difference between the LUMO energy level of the first organic compound and the LUMO energy level of the second organic compound is 0.2 eV or more and 0.8 eV or less.

[0027] In the above light-emitting device, the second electrode contains at least one of Ag, Mg, and Al.

[0028] In addition, one embodiment of the present invention is a light-emitting device including a plurality of the above light-emitting devices. Each of the plurality of light-emitting devices is any of the above light-emitting devices. Each of the plurality of light-emitting devices includes an organic compound layer including a light-emitting layer and an electron injection layer disposed between a first electrode and a second electrode. The organic compound layers included in the plurality of light-emitting devices are independent of each other among the plurality of light-emitting devices.

[0029] In addition, one embodiment of the present invention is a display module including the above light-emitting device and at least one of a connector and an integrated circuit.

[0030] In addition, one embodiment of the present invention is an electronic device including the above light-emitting device and at least one of a housing, a battery, a camera, a speaker, and a microphone.

[0031] According to one embodiment of the present invention, a novel light-emitting device can be provided. In addition, according to one embodiment of the present invention, a light-emitting device having good efficiency can be provided. In addition, according to one embodiment of the present invention, a light-emitting device having good reliability can be provided. In addition, according to one embodiment of the present invention, a light-emitting device having good efficiency and reliability can be provided.

[0032] In addition, according to one aspect of the present invention, a novel light-emitting device manufactured through a photolithography process can be provided. In addition, according to one aspect of the present invention, a light-emitting device having good efficiency manufactured through a photolithography process can be provided. In addition, according to one aspect of the present invention, a light-emitting device having good reliability manufactured through a photolithography process can be provided. In addition, according to one aspect of the present invention, a light-emitting device having good luminous efficiency and reliability manufactured through a photolithography process can be provided.

[0033] In addition, according to one aspect of the present invention, a novel light-emitting device applicable to a high-definition display device can be provided. In addition, according to one aspect of the present invention, a light-emitting device having good efficiency applicable to a high-definition display device can be provided. In addition, according to one aspect of the present invention, a light-emitting device having good reliability applicable to a high-definition display device can be provided. In addition, according to one aspect of the present invention, a light-emitting device having good luminous efficiency and reliability applicable to a high-definition display device can be provided.

[0034] In addition, according to one aspect of the present invention, a display device with high reliability can be provided. In addition, according to one aspect of the present invention, a high-definition display device can be provided. In addition, according to one aspect of the present invention, a high-definition and highly reliable display device can be provided.

[0035] In addition, according to one aspect of the present invention, a novel organic compound, a novel light-emitting device, a novel display device, a novel display module, and a novel electronic device can be provided.

[0036] Note that the description of these effects does not preclude the existence of other effects. One aspect of the present invention does not necessarily have all of the above effects. Effects other than the above can be extracted from the descriptions in the specification, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1A and Figure 1B is a diagram showing a light-emitting device; Figure 2A and Figure 2B is a diagram showing a light-emitting device; Figure 3A and Figure 3B is a diagram showing a light-emitting device; Figure 4A and Figure 4B are a top view and a cross-sectional view of a light-emitting device; Figures 5A to 5D is a diagram showing a light-emitting device; Figures 6A to 6E is a cross-sectional view showing an example of a manufacturing method of a display device; Figure 7A and Figure 7B is a cross-sectional view showing an example of a method for manufacturing a display device; Figures 8A to 8D is a cross-sectional view showing an example of a method for manufacturing a display device; Figures 9A to 9C is a cross-sectional view showing an example of a method for manufacturing a display device; Figures 10A to 10C is a cross-sectional view showing an example of a method for manufacturing a display device; Figures 11A to 11C is a cross-sectional view showing an example of a method for manufacturing a display device; Figures 12A to 12G is a top view showing an example of the structure of a pixel; Figures 13A to 13I is a top view showing an example of the structure of a pixel; Figure 14A and Figure 14B is a perspective view showing an example of the structure of a display module; Figure 15A and Figure 15B is a cross-sectional view showing an example of the structure of a display device; Figure 16 is a perspective view showing an example of the structure of a display device; Figure 17 is a cross-sectional view showing an example of the structure of a display device; Figure 18 is a cross-sectional view showing an example of the structure of a display device; Figures 19A to 19C is a view showing an example of the structure of a display device; Figure 20 is a cross-sectional view showing an example of the structure of a display device; Figures 21A to 21C is a view showing an example of the structure of a display device; Figures 22A to 22D is a view showing an example of an electronic device; Figures 23A to 23F is a view showing an example of an electronic device; Figures 24A to 24G is a view showing an example of an electronic device; Figure 25 is a view illustrating the structure of a light-emitting device; Figures 26A to 26D is a view illustrating the observation result of an optical microscope of a sample; Figure 27 is a view illustrating the luminance-current density characteristics of a light-emitting device; Figure 28 is a view illustrating the luminance-voltage characteristics of a light-emitting device; Figure 29 is a diagram showing the current efficiency - luminance characteristics of a light - emitting device; Figure 30 is a diagram showing the current density - voltage characteristics of a light - emitting device; Figure 31 is a diagram showing the electroluminescence spectrum of a light - emitting device; Figure 32 is a diagram showing the luminance change of a light - emitting device with respect to the driving time; Figure 33A and Figure 33B is a diagram showing the 1 1H - NMR spectrum of an organic compound; Figure 34A and Figure 34B is a diagram showing the 1 1H - NMR spectrum of an organic compound. Detailed Embodiments

[0038] The embodiments will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the following description, and those of ordinary skill in the art can easily understand the fact that its modes and details can be changed into various forms without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited only to the content described in the following embodiments.

[0039] Ordinal numbers such as "first", "second", etc. in this specification and the like are for avoiding confusion of components, and do not indicate an order or sequence such as a process order or a stacking order. In addition, in order to avoid confusion of components, even in the sentences in this specification and the like without ordinal numbers, ordinal numbers may sometimes be attached to them in the claims. For the sentences with ordinal numbers attached in this specification and the like, different ordinal numbers may sometimes be attached in the claims. For the sentences with ordinal numbers attached in this specification and the like, the ordinal numbers may sometimes be omitted in the claims.

[0040] Note that in this specification and the like, a device manufactured using a metal mask or an FMM (Fine Metal Mask) is sometimes referred to as a device having an MM (Metal Mask) structure. In addition, in this specification and the like, a device not manufactured using a metal mask or an FMM is sometimes referred to as a device having an MML (Metal Mask Less) structure.

[0041] Embodiment 1 Figure 1AA schematic diagram of a light-emitting device according to an aspect of the present invention. A first electrode 101 of the light-emitting device is provided on an insulator 109, and an organic compound layer 103 (also referred to as an EL layer) is included between the first electrode 101 and the second electrode 102. The organic compound layer 103 includes at least a light-emitting layer 113 and an electron injection layer 115. The light-emitting layer 113 is a layer containing a light-emitting substance and emits light when a voltage is applied between the first electrode 101 and the second electrode 102.

[0042] Preferably, as Figure 1A shown, in addition to the light-emitting layer 113 and the electron injection layer 115, the organic compound layer 103 includes functional layers such as a hole injection layer 111, a hole transport layer 112, and an electron transport layer 114. Note that the organic compound layer 103 may also include functional layers other than the above functional layers such as a hole blocking layer, an electron blocking layer, an exciton blocking layer, and an intermediate layer. Conversely, any of the above layers may not be provided.

[0043] As one of the methods for forming an organic film into a specified shape, a vacuum evaporation method using a metal mask (mask evaporation) is widely used. However, recently, with the progress of high density and high definition, due to various reasons represented by problems in position alignment accuracy and problems in the arrangement interval with the substrate, the further high definition of mask evaporation is approaching its limit. On the other hand, it is desired to realize an organic semiconductor device having a denser pattern by processing the shape of the organic film using a photolithography method. Furthermore, the photolithography method is easier to achieve large area formation than mask evaporation, and thus research on organic film processing using the photolithography method is underway.

[0044] On the other hand, it has been known that the organic compound layer in an organic EL device is affected by atmospheric components such as water and oxygen, and the EL layer is processed in an atmosphere of approximate vacuum in common sense steps.

[0045] In particular, an electron injection layer of a light-emitting device often uses an alkali metal or an alkaline earth metal or a compound thereof (hereinafter also referred to as a Li compound, etc.), but these Li compounds, etc. have high reactivity with water or oxygen and rapidly deteriorate when exposed to the atmosphere and lose their function as an electron injection layer.

[0046] However, in the above process of processing using a photolithography method, the surface of the organic compound layer is inevitably exposed to the atmosphere. Therefore, when processing using a photolithography method, the electron injection property of the electron injection layer using an alkali metal compound, etc. is significantly reduced. As a result, the driving voltage of an organic EL device processed using a photolithography method including an electron injection layer using an alkali metal compound, etc. rises and it is difficult to obtain good characteristics.

[0047] Here, in one aspect of the present invention, by using a first organic compound including a phenanthroline skeleton having an electron-donating group as the electron injection layer 115, an organic EL device having good characteristics can be obtained even after a photolithography process of atmospheric exposure of the organic compound layer (EL layer).

[0048] In addition, the solubility of the first organic compound for the electron injection layer 115 in pure water is 20 mg / L or less, preferably 10 mg / L or less, more preferably 8 mg / L or less. Further, when the detection lower limit value of the solubility is 1 mg / L, the solubility in pure water is 20 mg / L or less, preferably 1 mg / L or more and 10 mg / L or less. Alternatively, when the detection lower limit of the solubility measurement method is 0.1 mg / L or less, it is set to 0.1 mg / L or more and 20 mg / L or less, preferably 10 mg / L or less. Note that the lower limit value of the solubility of the first organic compound is the lowest value that can be detected according to the measurement method.

[0049] By using an organic compound having a solubility in pure water of 20 mg / L or less, a light-emitting device having good characteristics can be obtained even when treated with water or a liquid medicine using water as a solvent (i.e., processing by photolithography) in the manufacturing process.

[0050] In addition, the glass transition temperature (Tg) of the first organic compound for the electron injection layer 115 is 80 °C or higher, preferably 100 °C or higher and 180 °C or lower, more preferably 100 °C or higher and 130 °C or lower. When the glass transition temperature (Tg) is 80 °C or higher, the heat resistance is improved, and a light-emitting device having good characteristics can be obtained even when subjected to the heat treatment required for the deposition process or the heat treatment of the drying process.

[0051] And, the above-mentioned first organic compound contacts the second electrode 102 and interacts with the metal or metal oxide for the second electrode 102. That is, by the interaction between the first organic compound for the electron injection layer 115 and the metal or metal oxide for the second electrode 102, a donor energy level (singly occupied molecular orbital (SOMO) energy level or highest occupied molecular orbital (HOMO) energy level) is formed. By the interaction between the electron injection layer 115 and the second electrode 102, the donor energy level (SOMO energy level or HOMO energy level) becomes a high energy level, and the electron injection barrier from the electron injection layer 115 to the electron transport layer 114 can be reduced.

[0052] Note that the energy levels of the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) of the first organic compound are generally estimated by cyclic voltammetry (CV), photoelectron spectroscopy, photoabsorption spectroscopy, inverse photoelectron spectroscopy, etc. When comparing the values of different compounds, it is preferable to use the values estimated by the same measurement for comparison.

[0053] In addition, the SOMO energy level is an orbital derived from the unpaired electrons contained in the metal. When the metal or metal oxide used for the second electrode 102 interacts with the first organic compound, the SOMO energy level can also be distributed on the orbitals of the first organic compound. In other words, it can be said that the electron orbitals of the metal or metal oxide interact with the electron orbitals of the first organic compound.

[0054] In addition, as the atoms in the first organic compound that can interact with the metal or metal oxide, heteroatoms having lone pairs of electrons can be cited. For example, oxygen (O), nitrogen (N), sulfur (S), and phosphorus (P) can be cited, and nitrogen is preferred. Since nitrogen has a high electronegativity, it is easy to generate an interaction with the metal or metal oxide. In addition, since nitrogen can form a conjugated bond in the first organic compound, an organic compound with high carrier transportability can be realized by using nitrogen in the molecule, particularly in a heteroaromatic ring. Note that the heteroaromatic ring is more preferably an even-membered ring such as a six-membered ring or an eight-membered ring. By adopting this structure, the lone pair of electrons on nitrogen is not involved in conjugation, so it is easy to generate an interaction with the metal or metal oxide.

[0055] In other words, the metal or metal oxide and the first organic compound form a donor energy level (SOMO energy level or HOMO energy level) through interaction, which can reduce the electron injection barrier to the electron transport layer 114, and electrons can be smoothly injected from the electron injection layer 115 to the electron transport layer 114 and transported, so a light-emitting device with a low driving voltage can be manufactured.

[0056] Furthermore, as the electron transport layer 114 provided in contact with the electron injection layer 115, a second organic compound having a π-deficient heteroaromatic ring with a lone pair of electrons is preferably used. By using a metal or metal oxide for the second electrode 102, a first organic compound having an electron-donating substituent for the electron injection layer 115, and a second organic compound having a π-deficient heteroaromatic ring for the electron transport layer 114, a stable interaction can be generated.

[0057] In addition, in the above structure, since the first organic compound has an electron-donating substituent and thus has a high HOMO level and LUMO level, the difference between the LUMO level of the second organic compound for the electron injection layer 115 and the LUMO level of the organic compound for the electron transport layer 114 can be increased. In other words, when a metal or metal oxide (second electrode), the first organic compound having an electron-donating substituent (electron injection layer 115), and the second organic compound having a π-deficient heteroaromatic ring (electron transport layer 114) interact with each other, further stabilization can be achieved.

[0058] Note that the difference between the LUMO level of the organic compound for the electron injection layer 115 and the LUMO level of the organic compound for the electron transport layer 114 is preferably 0.2 eV or more and 0.8 eV or less.

[0059] In addition, as the second electrode 102, it is preferable to use transition metals such as Ag, Mg, Al (metal elements in Groups 3 to 11) and metal elements in Groups 12 to 14 of typical metals. In particular, Ag (silver) has low reactivity with oxygen and water in the atmosphere and water and chemical solutions used in the lithography process. Therefore, when it is used in a light-emitting device, there is less deterioration caused by water and oxygen that may occur when using a metal with a small work function.

[0060] As described above, since stabilization can be achieved when the metal or metal oxide for the second electrode 102 interacts with the organic compound for the electron injection layer, even after a lithography process including exposure of the organic compound layer 103 including the electron injection layer 115 to the atmosphere, electrons can be smoothly injected from the electron injection layer 115 and transported to the adjacent electron transport layer. Therefore, a light-emitting device with an inhibited rise in driving voltage, good luminous efficiency, and good reliability can be manufactured using the lithography process.

[0061] Thus, the light-emitting device structure of one embodiment of the present invention is resistant to oxygen and water in the atmosphere and water and chemical solutions used in the lithography process, and therefore, a light-emitting device with good moisture resistance, water resistance, oxygen resistance, chemical resistance, low driving voltage, and good luminous efficiency can be provided.

[0062] <<First Organic Compound That Can Be Used for the Electron Injection Layer 115>> Next, an organic compound that interacts with a metal or metal oxide will be described.

[0063] As the first organic compound, an organic compound including a π-deficient heteroaromatic ring can be used. Further, in order for the first organic compound to interact with a metal or a metal oxide and act as an electron donor (electron giver) to the second organic compound, the π-deficient heteroaromatic ring preferably has a non-bonding electron pair, and the non-bonding electron pair preferably has an electron-donating property. That is, the first organic compound preferably includes a basic π-deficient heteroaromatic ring. Further, since nitrogen has a high electronegativity, it easily interacts with a metal or a metal oxide. Further, since nitrogen can form a conjugated bond in an organic compound, by using nitrogen in a molecule, particularly in a heteroaromatic ring, an organic compound with high carrier transport property can be realized. Therefore, the first organic compound preferably includes a heteroaromatic ring containing nitrogen. Note that the heteroaromatic ring is more preferably an even-membered ring such as a six-membered ring or an eight-membered ring. By adopting this structure, the non-bonding electron pair on nitrogen is not involved in conjugation, and thus it easily interacts with a metal or a metal oxide. Further, in order to smoothly inject and transport electrons from the electron injection layer to the electron transport layer, the first organic compound preferably has an electron transport property. Specifically, for example, the first organic compound preferably includes a pyridine ring.

[0064] Further, the first organic compound is preferably a material including two or more π-deficient heteroaromatic rings having non-bonding electron pairs, and the two or more π-deficient heteroaromatic rings are bonded or fused to each other. Thereby, when a metal or a metal oxide as a bidentate ligand or a polydentate ligand having two or more teeth interacts with the first organic compound and the second organic compound, it becomes stable, and thus an electron injection layer that is not easily deteriorated even after a photolithography process accompanied by exposure to the atmosphere can be formed. Specifically, for example, the first organic compound preferably includes a heteroaromatic ring containing two or more pyridine rings. Among them, the nitrogen atom of an organic compound having a bipyridine skeleton easily coordinates with a metal, and thus it easily interacts with a metal or a metal oxide, and is therefore preferred.

[0065] Further, a phenanthroline ring has rigidity and high stability, and is therefore preferred. In particular, in a phenanthroline ring, two nitrogen atoms in an organic compound having a 1,10-phenanthroline ring can coordinate to a metal, and thus it easily interacts with a metal or a metal oxide, and is therefore preferred.

[0066] Further, the first organic compound may also have a structure in which a plurality of phenanthroline rings are connected by a single bond or through a divalent group. As a specific example of the divalent group, for example, an alkylene group, an arylene group, etc. can be cited.

[0067] An alkylene group represents a divalent group obtained by removing two hydrogen atoms from an alkane. As a specific example of the alkylene group, a divalent group having a structure in which one hydrogen atom is further removed from the specific examples of the alkyl group described later can be cited.

[0068] An arylene represents a divalent group obtained by removing two hydrogen atoms from an aromatic hydrocarbon. As a specific example, a divalent group having a structure in which one hydrogen atom is further removed from the specific examples of the aryl group described below can be cited. The arylene may also have a substituent, and specific examples of the substituent include an alkyl group, an alkoxy group, a phenyl group, and the like.

[0069] In addition, the first organic compound preferably has an electron-donating substituent. Thereby, since the first organic compound can have a high HOMO energy level and a high LUMO energy level, the difference between the LUMO energy level of the first organic compound and the LUMO energy level of the second organic compound can be increased, and when the metal or metal oxide, the first organic compound, and the second organic compound interact, further stabilization of the intermediate layer can be achieved, so that an electron injection layer that is not easily deteriorated even after a photolithography process accompanied by atmospheric exposure can be formed.

[0070] In addition, as the first organic compound, an organic compound including a phenanthroline ring having an electron-donating group is more preferably used. In particular, by introducing an electron-donating group into the 1,10-phenanthroline ring, the electron density of the phenanthroline ring can be increased, and the efficiency of interaction with a metal or metal oxide can be improved. And preferably, at least one of the 4-position and the 7-position of the 1,10-phenanthroline ring has an electron-donating group. By introducing an electron-donating group at the 4-position and the 7-position, the electron density of the nitrogen atoms at the 1-position and the 10-position para thereto can be increased. In addition, steric hindrance around the nitrogen atoms at the 1-position and the 10-position can be avoided, and the electron density around the nitrogen atoms can be increased. Therefore, it can easily interact with a metal or metal oxide, so it is preferred.

[0071] When measuring an organic compound by nuclear magnetic resonance spectroscopy ( 1 H-NMR), a deviation in the resonance frequency occurs due to the influence of the electron density as the chemical environment in which the nuclide ( 1 H) is located, and a chemical shift occurs in the 1 H-NMR spectrum. For example, when the electron density of the nuclide ( 1 H) becomes high, a signal appears on the high magnetic field side (0 ppm) in the 1 H-NMR spectrum, and thus it can be known that the electron density near the nuclide ( 1 H) becomes high. When the electron density of the nitrogen atoms at the 1-position and the 10-position of the 1,10-phenanthroline ring is high, the electron density of the adjacent hydrogen atoms ( 1 H) at the 2-position and the 9-position or the 3-position and the 8-position is also high, and therefore a signal appears on the high magnetic field side (0 ppm) in the 1 H-NMR spectrum.

[0072] Specifically, the state that is liable to produce an interaction with a metal refers to the state in which the hydrogens (H) at the 2-position and 9-position adjacent to the nitrogen (N) in the 1,10-phenanthroline skeleton of the first organic compound are chemically shifted toward the high magnetic field side. This is because: by the substituents bonded to the phenanthroline skeleton of the first organic compound supplying electrons to the phenanthroline skeleton, the electron density of the nitrogen in the phenanthroline skeleton is increased.

[0073] In addition, when a substituent is bonded to the 2-position or 9-position of the phenanthroline skeleton of the first organic compound, the hydrogen (H) at the 3-position or 8-position adjacent to the substituent is chemically shifted toward the high magnetic field side.

[0074] In particular, for an interaction with a Group 13 metal such as In, the 1 chemical shift of the 1H-NMR is less than 7.5 ppm, preferably 7.0 ppm or less.

[0075] Specific examples of the electron-donating group include an alkyl group, an alkoxy group, an aryloxy group, an alkylamino group, an arylamino group, a heterocyclic amino group, etc. However, the electron-donating group preferably introduced into a π-deficient heteroaromatic ring such as a phenanthroline ring is not limited thereto. As long as a group that can increase the electron density of a π-deficient heteroaromatic ring is introduced into a π-deficient heteroaromatic ring such as a phenanthroline ring, it can be used as the electron-donating group. In addition, the electron-donating group may also be introduced into a π-deficient heteroaromatic ring such as a phenanthroline ring via an arylene group such as a phenylene group, and the arylene group is preferably a p-phenylene group.

[0076] An alkyl group represents a monovalent group obtained by removing one hydrogen atom from an alkane (C n H 2n+2 ). Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a neopentyl group, a hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, a neohexyl group, a 3-methylpentyl group, a 2-methylpentyl group, a 2-ethylbutyl group, a 1,2-dimethylbutyl group, a 2,3-dimethylbutyl group, etc.

[0077] An alkoxy group represents a monovalent group having a structure in which an alkyl group is bonded to an oxygen atom. Specific examples of the alkoxy group include a methoxy group, an ethoxy group, a n-propoxy group, an isopropoxy group, a n-butoxy group, a sec-butoxy group, an isobutoxy group, a tert-butoxy group, a n-pentyloxy group, an isopentyloxy group, a sec-pentyloxy group, a tert-pentyloxy group, a neopentyloxy group, a n-hexyloxy group, an isohexyloxy group, a sec-hexyloxy group, a tert-hexyloxy group, a neohexyloxy group, etc.

[0078] An aryloxy group represents a monovalent group having an aryl group bonded to an oxygen atom. An aryl group represents a monovalent group obtained by removing one hydrogen atom from one of the ring-forming carbon atoms of a monocyclic or polycyclic aromatic compound. Specific examples of the aryloxy group include a phenoxy group, an o-tolyloxy group, an m-tolyloxy group, a p-tolyloxy group, a mesityloxy group, an o-biphenylyloxy group, an m-biphenylyloxy group, a p-biphenylyloxy group, a 1-naphthyloxy group, a 2-naphthyloxy group, a 2-fluorenyloxy group, etc. The aryloxy group may also have a substituent. Specific examples of the substituent include an alkyl group, an alkoxy group, a phenyl group, etc.

[0079] An alkylamino group represents a monovalent group obtained by removing one hydrogen from the nitrogen atom of a primary or secondary amine in which one or two alkyl groups are bonded to the nitrogen atom. Specific examples of the alkylamino group include, for example, a dimethylamino group, a diethylamino group, etc.

[0080] An arylamino group represents a monovalent group obtained by removing one hydrogen from the nitrogen atom of a primary or secondary amine in which one or two aryl groups are bonded to the nitrogen atom. Specific examples of the arylamino group include a diphenylamino group, a bis(α-naphthyl)amino group, a bis(m-tolyl)amino group, etc. The arylamino group may also have a substituent. Specific examples of the substituent include an alkyl group, an alkoxy group, a phenyl group, etc.

[0081] In addition, an amino group having a structure in which both an alkyl group and an aryl group are bonded to the nitrogen atom can be said to be either an alkylamino group or an arylamino group. Specific examples of such an amino group include, for example, an N-methyl-N-phenylamino group, etc.

[0082] A heterocyclic amino group represents a monovalent group obtained by removing one hydrogen atom from one of the ring-forming nitrogen atoms of a heterocyclic amine. Note that here, the heterocyclic amine refers to a monocyclic or polycyclic heterocyclic compound and represents a compound in which at least one of the ring-forming atoms is a nitrogen atom bonded to a hydrogen atom. Specific examples of the heterocyclic amino group include the groups represented by the following structural formulas (R-1) to (R-26). Note that the heterocyclic amino group may also have a substituent. Specific examples of the substituent include an alkyl group, an alkoxy group, a phenyl group, etc.

[0083] [Chemical formula 2]

[0084] Note that when the heterocyclic amino group is aromatic and the non-bonding electron pair of the nitrogen atom contributes to the aromaticity, the electron-donating property to the phenanthroline ring sometimes decreases compared to the case where the non-bonding electron pair of the nitrogen atom does not contribute to the aromaticity. Therefore, among the above heterocyclic amino groups, a heterocyclic amino group in which the non-bonding electron pair of the nitrogen atom does not contribute to the aromaticity is more preferably used. Specifically, the groups represented by structural formula (R-1), structural formula (R-2), structural formula (R-3), structural formula (R-4), structural formula (R-5), structural formula (R-8), structural formula (R-9), structural formula (R-10), structural formula (R-12), structural formula (R-14), structural formula (R-15), structural formula (R-16), structural formula (R-17), or (R-21) are more preferably used as electron-donating groups. Among them, the groups represented by structural formula (R-3), structural formula (R-4), structural formula (R-8), or structural formula (R-21) have high electron-donating properties and can further increase the electron density of the phenanthroline ring, so they are preferred.

[0085] In addition, as specific examples of the electron-donating group, the groups represented by the following structural formulas (R-27) and (R-29) can be cited.

[0086] [Chemical formula 3]

[0087] Note that the organic compound including a π-deficient heterocyclic ring that can be used as the first organic compound may also have both the above electron-donating group and substituents other than that. As specific examples of the substituents other than the above electron-donating group that can be introduced into the π-deficient heterocyclic ring, aryl groups can also be cited. As specific examples of the aryl group, phenyl, o-tolyl, m-tolyl, p-tolyl, mesityl, o-biphenylyl, m-biphenylyl, p-biphenylyl, 1-naphthyl, 2-naphthyl, 2-fluorenyl, etc. can be cited. The aryl group may also have substituents. As specific examples of the substituent, alkyl groups, alkoxy groups, phenyl groups, etc. can be cited.

[0088] The organic compounds represented by structural formula (100) and structural formulas (301) to (307) are specific examples of the organic compounds including a π-deficient heterocyclic ring that can be used as the first organic compound. Note that the organic compounds that can be used as the first organic compound are not limited thereto.

[0089] [Chemical formula 4]

[0090] In addition, when the minimum negative value of the electrostatic potential (ESP) of the first organic compound is small (the absolute value of the negative value is large), the stability of the interaction with a metal or metal oxide is improved, which is therefore preferred. In an organic compound including a π-deficient heteroaromatic ring, the electrostatic potential tends to have a negative value around the nitrogen atom of the π-deficient heteroaromatic ring. However, by introducing an electron-donating group onto the π-deficient heteroaromatic ring, the electrostatic potential around the nitrogen atom of the π-deficient heteroaromatic ring can be further reduced (the absolute value of the negative value is increased). The electrostatic potential refers to the interaction energy between a positive point charge with a unit electric charge and the electron distribution of a molecule. In addition, the value of the electrostatic potential also varies according to the threshold value of the electron density distribution. In order to improve the efficiency of the interaction with a metal or metal oxide, the minimum value of the electrostatic potential of the first organic compound is preferably smaller (larger in the negative direction) than the minimum value of the electrostatic potential of a phenanthroline ring without substituents. Specifically, when the threshold value of the electron density distribution in atomic units is 0.0004e / a0 3 the minimum value of the electrostatic potential is preferably -0.085 E h (E h represents Hartree energy (1 E h = 27.211 eV)) or less, more preferably -0.090 E h or less, even more preferably -0.092 E h or less. In addition, when the threshold value of the electron density distribution is 0.003e / a0 3 the minimum value of the electrostatic potential is preferably -0.12 E h or less, more preferably -0.13 E h or less.

[0091] <<Estimating the properties of the first organic compound using quantum chemical calculations>> Estimate the minimum value of the electrostatic potential (ESP) of the organic compound that can be used as the first organic compound described above using quantum chemical calculations.

[0092] As the quantum chemical calculation program, Gaussian09 is used. The calculation is performed using SGI8600 manufactured by HPE. The most stable structure of the first organic compound in the ground state is calculated using density functional theory (DFT). 6-311G(d, p) is used as the basis function and B3LYP is used as the functional.

[0093] The following table shows the analysis results of the electrostatic potential in the ground state of the first organic compound. The electrostatic potential refers to the interaction energy between a positive point charge with a unit electric charge and the electron distribution of the molecule. In addition, the value of the electrostatic potential also varies according to the threshold of the electron density distribution. The following table shows the electrostatic potential of the electron density distribution when the threshold of the electron density distribution is set to 0.0004 e / a0 3 or 0.003 e / a0 3 in atomic units.

[0094] [Table 1]

[0095] Note that the organic compounds represented by Structural Formulas (100) and (301) to (307) in the table can be referred to the above description. In addition, the following shows the structural formulas of Bphen, mPPhen2P, NBphen, and Phen in the table shown as the organic compounds that can be used as the first organic compound.

[0096] [Chemical Formula 5]

[0097] As can be seen from the above table, in the organic compounds represented by Structural Formulas (100) and (301) to (303), when the threshold of the electron density distribution is 0.0004 e / a0 3 in atomic units, the minimum value of ESP is -0.085 E h Therefore, it is most suitable as the first organic compound. On the other hand, it can be seen that the minimum value of ESP of the organic compounds represented by Structural Formulas (304) to (307) is greater than -0.085 E h .

[0098] It can be seen that the organic compounds represented by Structural Formulas (100) and (301) to (303) are organic compounds having electron-donating groups at the 4th and 7th positions of the 1,10-phenanthroline ring, and thus have the most preferable values.

[0099] The organic compound represented by Structural Formula (304) is an organic compound having electron-donating groups at the 4th and 7th positions of the 1,10-phenanthroline ring, and uses an N-carbazolyl group as the electron-donating group. In the N-carbazolyl group, the non-bonding electron pair of the nitrogen atom contributes to aromaticity. Therefore, compared with the group in which the non-bonding electrons of the nitrogen atom do not contribute to aromaticity, the electron-donating property to the phenanthroline ring is reduced, and thus the minimum value of ESP is not easily decreased, resulting in the above results.

[0100] The organic compounds represented by structural formulas (305) to (307) are organic compounds having electron-donating groups at the 2-position and 9-position of the 1,10-phenanthroline ring. The electron-donating groups introduced at the 2-position and 9-position have low electron-donating ability to the nitrogen atoms at the 1-position and 10-position of the phenanthroline ring. Therefore, the electron-donating groups in the 1,10-phenanthroline ring are preferably located at the 4-position and 7-position.

[0101] Note that the LUMO energy level of the second organic compound is more preferably lower than the LUMO energy level of the first organic compound. Thereby, electrons can be easily supplied from the donor energy level formed by the first organic compound and the metal or metal oxide to the second organic compound. In addition, the second organic compound preferably has electron-transporting properties, and for this purpose, the LUMO energy level of the second organic compound is preferably lower than the LUMO energy level of the first organic compound.

[0102] For example, the LUMO energy level of the first organic compound is preferably -3.0 eV or more and -2.0 eV or less, more preferably -2.7 eV or more and -2.0 eV or less. In addition, the LUMO energy level of the second organic compound is preferably -3.0 eV or more and -2.0 eV or less, more preferably -3.0 eV or more and -2.5 eV or less. Thereby, electrons can be easily supplied from the donor energy level formed by the first organic compound and the metal or metal oxide to the second organic compound. In addition, electron transport in the second organic compound becomes easy thereby.

[0103] Note that the HOMO energy level and LUMO energy level of an organic compound are generally estimated by methods such as CV (cyclic voltammetry), photoelectron spectroscopy, photoabsorption spectroscopy, inverse photoelectron spectroscopy, etc. When comparing the values of different compounds, it is preferable to use the values estimated by the same measurement for comparison.

[0104] In addition, when the first organic compound has a high basicity, the hole-transporting property of the electron injection layer can be significantly reduced by interacting with holes to prevent holes from being transported from the electron injection layer to the electron transport layer, and thus a highly efficient light-emitting device can be obtained, so it is preferable. Specifically, the acidity coefficient pKa is preferably 8 or more, more preferably 10 or more, and further preferably 12 or more.

[0105] In addition, when the acidity coefficient pKa of the organic compound is unknown, by investigating the acidity coefficient pKa of each skeleton of the organic compound, the largest acidity coefficient pKa among them can be regarded as the acidity coefficient pKa of the organic compound.

[0106] In addition, the acidity coefficient can also be calculated. For example, the acidity coefficient pKa can be calculated using the following calculation method.

[0107] The initial structure of the molecular structure of each molecule as a computational model adopts the most stable structure (singlet ground state) obtained by first-principles calculation.

[0108] As the above first-principles calculation, use Jaguar, a quantum chemistry calculation software manufactured by Inc., calculates the most stable structure in the singlet ground state through density functional theory (DFT). Use 6-31G** as the basis function and B3LYP-D3 as the functional. As the structure for performing quantum chemistry calculations, use Maestro GUI manufactured by Inc., and perform conformational analysis with Mixed torsional / Low-mode sampling for sampling.

[0109] In the pKa calculation, one or more atoms in each molecule are designated as basic positions. Use Macro Model to explore the structure in which the protonated molecule is stable in water, and use the conformational isomer with the lowest energy obtained by conformational exploration using the OPLS2005 force field. Use the pKa calculation module of Jaguar to optimize its structure with B3LYP / 6-31G*, then perform a single-point calculation with cc-pVTZ(+), and calculate the pKa value using the empirical correction for functional groups. Among the molecules in which one or more atoms are designated as basic positions, use the largest value in the obtained results as the pKa value. Show the obtained pKa values.

[0110] The acidity coefficient pKa of 2,9hpp2Phen is 13.35, the acidity coefficient pKa of 4,7hpp2Phen is 13.42, the acidity coefficient pKa of Pyrrd-Phen is 11.23, the acidity coefficient pKa of mPPhen2P is 5.16, the acidity coefficient pKa of NBphen is 5.59, and the acidity coefficient pKa of Bphen is 5.62.

[0111] <<Metals or metal oxides that can be used for the second electrode 102>> As the metal, typical metals or transition metals can be used.

[0112] As typical metals, alkali metals (Group 1 elements) such as Li, Na, K, Cs, alkaline earth metals (Group 2 elements) such as Mg, Ca, Ba, Group 12 elements such as Zn, earth metals (Group 13 elements) such as Al, In, Group 14 elements such as Sn, or their compounds can be used.

[0113] When an alkali metal, an alkaline earth metal, or a compound thereof is used as the metal, the donor energy level formed by the interaction between the first organic compound and the second organic compound can be a high energy level. As a result, electrons can be smoothly injected from the electron injection layer and transported to the electron transport layer, and a light-emitting device with a low driving voltage and high-efficiency light emission can be provided, so it is preferred.

[0114] As the transition metal, a Group 3 element including Y and lanthanide elements such as Eu and Yb, a Group 7 element such as Mn, a Group 8 element such as Fe, a Group 9 element such as Co, a Group 10 element such as Ni and Pt, a Group 11 element such as Cu, Ag, and Au, or a compound thereof can be used. The transition metal has low reactivity with components such as water and oxygen in the atmosphere, so it is preferred.

[0115] Among the above metals, it is more preferred to use a metal belonging to an odd group (Group 1, Group 3, Group 5, Group 7, Group 9, Group 11, or Group 13). Among these transition metals belonging to odd groups, a metal having one electron (unpaired electron) in the outermost orbital is likely to form a SOMO with the first organic compound, so it is particularly preferred.

[0116] In addition, a metal with a low melting point and can be deposited by vacuum evaporation is likely to form a mixed layer with the organic compound, so it is preferred. Specifically, for example, metals belonging to Group 11 elements and Group 13 elements have low melting points, so they can be applied to vacuum evaporation. In addition, metals belonging to Group 11 elements and Group 13 elements are stable to oxygen and water in the atmosphere, so they are preferred.

[0117] <<Second organic compound that can be used for the electron transport layer 114>> The electron transport layer preferably has a π-deficient heteroaromatic ring. As the π-deficient heteroaromatic ring contained in the second organic compound, a heteroaromatic ring having an oxazole skeleton (imidazole ring, pyrazole ring, oxazole ring, thiazole ring, triazole ring, oxadiazole ring, thiadiazole ring), a heteroaromatic ring having a pyridine skeleton, a heteroaromatic ring having a diazine skeleton, and a heteroaromatic ring having a triazine skeleton are preferably used. Among them, a diazine ring (pyrazine ring, pyrimidine ring, pyridazine ring) or a triazine ring is electrochemically stable and has high electron transportability, so it is preferred.

[0118] By appropriately using the above metal or metal oxide, the above first organic substance, and the above second organic substance, a light-emitting device with high luminous efficiency can be provided.

[0119] Embodiment 2 In this embodiment, a light-emitting device according to one aspect of the present invention will be described in detail.

[0120] Figure 1ASchematic diagram of a light-emitting device according to an aspect of the present invention. In the light-emitting device, a first electrode 101 is provided on an insulator 109, and an organic compound layer 103 is included between the first electrode 101 and the second electrode 102. The organic compound layer 103 includes at least a light-emitting layer 113 and an electron injection layer 115. The light-emitting layer 113 is a layer containing a light-emitting substance and emits light when a voltage is applied between the first electrode 101 and the second electrode 102.

[0121] As Figure 1A shown, the organic compound layer 103 preferably includes functional layers such as a hole injection layer 111, a hole transport layer 112, an electron transport layer 114, and an electron injection layer 115 in addition to the light-emitting layer 113. In addition, the organic compound layer 103 may include functional layers such as a hole blocking layer, an exciton blocking layer, and an intermediate layer in addition to the above functional layers. Conversely, any of the above layers may not be provided.

[0122] In addition, the electron injection layer 115 is a layer including a metal or a metal oxide, an organic compound (first organic compound) containing a first π-deficient heteroaromatic ring having an electron-donating group, and an organic compound (second organic compound) having a second π-deficient heteroaromatic ring as described in Embodiment Mode 1. The electron injection layer 115 may further include other organic compounds (third organic compounds).

[0123] The specific structure of the electron injection layer 115 has been described in detail in Embodiment Mode 1, so repeated description is omitted here.

[0124] Note that although in the present embodiment, an example is shown in which the first electrode 101 is an electrode including an anode, the second electrode 102 is an electrode including a cathode, and the first electrode 101 is formed on one side of the insulator 109, a structure in which the second electrode 102 is formed on one side of the insulator 109, that is, a so-called reverse laminate structure, may also be employed. In this case, the light-emitting device has a laminate structure in which the second electrode 102, the electron injection layer 115, (the electron transport layer 114,) the light-emitting layer 113, (the hole transport layer 112, the hole injection layer 111,) and the first electrode 101 are laminated in this order from the insulator 109 side. When the light-emitting device having this reverse laminate structure is employed, the relatively stable hole injection layer 111 becomes the surface, and thus a light-emitting device with higher reliability can be realized.

[0125] In addition, the first electrode 101 and the second electrode 102 are formed into a single-layer structure or a laminate structure. When having a laminate structure, the layer in contact with the organic compound layer 103 is used as an anode or a cathode. When the electrode has a laminate structure, there is no limitation on the work function of the layers other than the layer in contact with the organic compound layer 103, and materials can be selected according to required characteristics such as resistance value, processability, reflectance, transmittance, and stability.

[0126] The anode is preferably formed of a metal, alloy, conductive compound, or a mixture thereof having a large work function (specifically, 4.0 eV or more). Specifically, for example, indium tin oxide (ITO), indium tin silicon oxide (ITSO) containing silicon or silicon oxide, indium zinc oxide, indium tungsten zinc oxide (IWZO) containing tungsten oxide and zinc oxide, etc. can be cited. Although these conductive metal oxide films are usually formed by sputtering, sol-gel methods or the like can also be applied. As an example of the forming method, a method of forming indium zinc oxide by sputtering using a target in which 1 wt% to 20 wt% of zinc oxide is added to indium oxide can be cited. In addition, indium tungsten zinc oxide (IWZO) containing tungsten oxide and zinc oxide can be formed by sputtering using a target in which 0.5 wt% to 5 wt% of tungsten oxide and 0.1 wt% to 1 wt% of zinc oxide are added to indium oxide. In addition, as materials for the anode, for example, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), titanium (Ti), aluminum (Al), or nitrides of metal materials (for example, titanium nitride) etc. can be cited. In addition, a layer formed by laminating them can also be used as the anode. For example, a film in which Al, Ti, and ITSO are sequentially laminated on Ti has high efficiency due to good reflectivity and can achieve a high resolution of several thousand ppi, so it is preferred. In addition, graphene can also be used as a material for the anode. In addition, by using a composite material that can form the hole injection layer 111 described later for the layer in contact with the anode (typically the hole injection layer), there is no need to consider the work function when selecting the electrode material.

[0127] The hole injection layer 111 is in contact with the anode and has a function of facilitating the injection of holes into the organic compound layer 103. Phthalocyanine compounds or complexes such as phthalocyanine (abbreviation: H2Pc) and copper phthalocyanine (abbreviation: CuPc) etc.; aromatic amine compounds such as 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), 4,4'-bis(N-{4-[N'-(3-methylphenyl)-N'-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNTPD) etc.; or polymers such as poly(3,4-ethylenedioxythiophene) / (polystyrene sulfonic acid) (abbreviation: PEDOT / PSS) etc. can be used to form the hole injection layer 111.

[0128] In addition, the hole injection layer 111 may also be composed of a substance having an electron-accepting property. As the substance having an electron-accepting property, an organic compound having an electron-withdrawing group (halogen group, cyano group) can be used, and examples thereof include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloroquinone, 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, and the like. In particular, compounds such as HAT-CN in which an electron-withdrawing group is bonded to a fused aromatic ring having a plurality of heteroatoms are thermally stable, and thus are preferred. In addition, [3]axylene derivatives including an electron-withdrawing group (especially a halogen group such as a fluorine group, a cyano group, etc.) have a very high electron-accepting property and are particularly preferred. Specifically, examples thereof include α,α',α''-1,2,3-cyclopropanetriylidene tris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α,α',α''-1,2,3-cyclopropanetriyl tris[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], α,α',α''-1,2,3-cyclopropanetriyl tris[2,3,4,5,6-pentafluorobenzeneacetonitrile], and the like. As the substance having an electron-accepting property, in addition to the above organic compounds, transition metal oxides such as molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, and manganese oxide can also be used.

[0129] In addition, the hole injection layer 111 is preferably formed using a composite material containing the above-mentioned material having an electron-accepting property and an organic compound having a hole-transporting property.

[0130] As the organic compound having a hole-transporting property for the composite material, various organic compounds such as aromatic amine compounds, heteroaromatic compounds, aromatic hydrocarbons, and polymer compounds (oligomers, dendrimers, polymers, etc.) can be used. As the organic compound having a hole-transporting property for the composite material, it is preferably an organic compound having a hole mobility of 1×10 -6 cm 2 / Vs or more. The organic compound having a hole-transporting property for the composite material is preferably a compound containing a fused aromatic hydrocarbon ring or a π-electron-rich heteroaromatic ring. As the fused aromatic hydrocarbon ring, an anthracene ring, a naphthalene ring, etc. are preferred. In addition, as the π-electron-rich heteroaromatic ring, a fused aromatic ring containing at least any one of a pyrrole skeleton, a furan skeleton, and a thiophene skeleton is preferred, and specifically, a carbazole ring, a dibenzothiophene ring, or a ring in which these rings are further fused with an aromatic ring or a heteroaromatic ring is preferred.

[0131] In addition, a composite material containing the above-described material having an electron-accepting property and an organic compound having a hole-transporting property effectively causes an interaction between the materials. Therefore, as the spin density measured by the electron spin resonance method (ESR) for the film containing the composite material, the spin density attributed to the signal observed around a g-value of 2.00 is preferably 1×10 17 spins / cm 3 or more.

[0132] Such an organic compound having a hole-transporting property preferably has any one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton. In particular, it may be an aromatic amine having a substituent including a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine including a naphthalene ring, or an aromatic monoamine in which 9-fluorenyl is bonded to the nitrogen of the amine via an arylene group. Note that when these organic compounds having a hole-transporting property are substances including N,N-bis(4-biphenyl)amino, a light-emitting device having a long lifetime can be manufactured, and thus they are preferred.

[0133] As the above-mentioned organic compound having hole-transporting properties, specifically, 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-aminotriphenylbenzene (abbreviation: DBfBB1TP), N-[4-(dibenzothiophen-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'-binaphthalen-2-yl)triphenylamine (abbreviation: BBAαNβNB), 4,4'-diphenyl-4''-(7;1'-binaphthalen-2-yl)triphenylamine (abbreviation: BBAαNβNB-03), 4,4'-diphenyl-4''-(7-phenyl)naphthalen-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4,4'-diphenyl-4''-(6;2'-binaphthalen-2-yl)triphenylamine (abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-(7;2'-binaphthalen-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diphenyl-4''-(4;2'-binaphthalen-1-yl)triphenylamine (abbreviation: BBAβNαNB), 4,4'-diphenyl-4''-(5;2'-binaphthalen-1-yl)triphenylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenyl)-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB), 4-(3-biphenyl)-4'[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: mTPBiAβNBi), 4-(4-biphenyl)-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(biphenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carbazol-9-yl)biphenyl-4-yl]-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBNBSF), N,N-bis(biphenyl-4-yl)-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: BBASF), N,N-bis(biphenyl-4-yl)-9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: BBASF(4)), N-(biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: oFBiSF), N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)dibenzofuran-4-amine (abbreviation: FrBiF), N-[4-(1-naphthyl)phenyl]-N-[3-(6-phenyldibenzofuran-4-yl)phenyl]-1-naphthylamine (abbreviation: mPDBfBNBN), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine (abbreviation: BPAFLBi), 4-phenyl-4'-(9-phenyl-9H-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'-bis(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF), N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF), N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluorene-4-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-Spirobi-9H-fluorene-3-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluorene-2-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi-9H-fluorene-1-amine, etc.

[0134] In addition, as materials having hole-transporting properties, as other aromatic amine compounds, N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), 4,4'-bis(N-{4-[N'-(3-methylphenyl)-N'-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), etc. can also be used.

[0135] By forming the hole injection layer 111, the hole injection property can be improved, and thus a light-emitting device with a low driving voltage can be obtained.

[0136] In addition, organic compounds having electron-accepting properties among substances having electron-accepting properties can be easily formed by vapor deposition, so they are materials that are easy to use.

[0137] The hole transport layer 112 is formed by including an organic compound having hole-transporting properties. As the organic compound having hole-transporting properties, it preferably has a hole mobility of 1×10 -6 cm 2 / Vs or more.

[0138] Examples of the above hole-transporting materials include compounds with an aromatic amine backbone such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviation: TPD), N,N'-bis(9,9'-spirobi[9H-fluorene]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (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'-bis(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]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF), etc.;1,3-Bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-bis(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 9,9'-diphenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCCP), 9,9'-bis(biphenyl-4-yl)-3,3'-bi-9H-carbazole (abbreviation: BisBPCz), 9,9'-bis(biphenyl-3-yl)-3,3'-bi-9H-carbazole (abbreviation: BismBPCz), 9-(biphenyl-3-yl)-9'-(biphenyl-4-yl)-9H,9'H-3,3'-bicarbazole (abbreviation: mBPCCBP), 9-(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: βNCCP), 9-(3-biphenyl)-9'-(2-naphthyl)-3,3'-bi-9H-carbazole (abbreviation: βNCCmBP), 9-(4-biphenyl)-9'-(2-naphthyl)-3,3'-bi-9H-carbazole (abbreviation: βNCCBP), 9,9'-di-2-naphthyl-3,3'-9H,9'H-bicarbazole (abbreviation: BisβNCz), 9-(2-naphthyl)-9'-[1,1':4',1''-terphenyl]-3-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':3',1''-terphenyl]-3-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':3',1''-terphenyl]-5'-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':4',1''-terphenyl]-4-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-[1,1':3',1''-terphenyl]-4-yl-3,3'-9H,9'H-bicarbazole, 9-(2-naphthyl)-9'-(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole, 9-phenyl-9'-(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole (abbreviation: PCCzTp), 9,9'-bis(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole, 9-(4-biphenyl)-9'-(triphenylene-2-yl)-3,3'-9H,9'H-bicarbazole, 9-(triphenylene-2-yl)-9'-[1,1':3',1''-terphenyl]-4-yl-3,3'-9H,9'H-bicarbazole and other compounds with a carbazole skeleton;Compounds with a thiophene backbone such as 4,4',4''-(benzene-1,3,5-triyl)tris(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); and compounds with a furan backbone such as 4,4',4''-(benzene-1,3,5-triyl)tris(dibenzofuran) (abbreviation: DBF3P-II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II). Among them, compounds with an aromatic amine backbone and compounds with a carbazole backbone have high reliability and excellent hole transport properties and contribute to reducing the driving voltage, so they are preferred. Note that materials having hole transport properties, which are also cited as materials for the hole injection layer 111, can also be appropriately used as materials constituting the hole transport layer 112.;

[0139] The light-emitting layer 113 is a layer containing a light-emitting substance, and preferably contains a light-emitting substance and a host material. Note that the light-emitting layer may also contain other materials. In addition, it may be a laminate of two layers with different compositions.

[0140] The light-emitting substance may be a fluorescent light-emitting substance, a phosphorescent light-emitting substance, a substance presenting thermally activated delayed fluorescence (TADF), or other light-emitting substances.

[0141] In the light-emitting layer, as materials that can be used as fluorescent light-emitting substances, for example, the following substances can be cited. Note that, in addition, other fluorescent light-emitting substances can also be used.

[0142] Examples include 5,6-bis[4-(10-phenyl-9-anthryl)phenyl]-2,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-anthryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenyldiphenyl-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra-tert-butyldiperylene (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-benzenediamine) (abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-benzenediamine (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(biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracen-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracen-9-amine (abbreviation: DPhAPhA), Coumarin 545T, N,N'-diphenylquinacridone (abbreviation: DPQd), Rubrene, 5,12-bis(biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]vinyl}-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)vinyl]-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)vinyl]-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)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]vinyl}-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)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), N,N'-diphenyl-N,N'-(1,6-pyrene-diyl)bis[(6-phenylbenzo[b]naphtho[1,2-d]furan)-8-amine (abbreviation: 1,6BnfAPrn-03), N,N'-diphenyl-N,N'-bis[(9-phenyl-9H-carbazol-2-yl)]naphtho[2,3-b;6,7-b']bisbenzofuran-3,10-diamine (abbreviation: 3,10PCA2Nbf(IV)-02), 3,10-bis[N-(dibenzofuran-3-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10FrA2Nbf(IV)-02), etc. In particular, fused aromatic diamine compounds represented by pyrene diamine compounds such as 1,6FLPAPrn, 1,6mMemFLPAPrn, 1,6BnfAPrn-03, etc. have high hole trapping properties, high luminous efficiency, and high reliability, so they are preferred.,

[0143] In addition, 5,9-diphenyl-5,9-diaza-13b-borataanthra[3,2,1-de]anthracene (abbreviation: DABNA1), 9-[(1,1'-diphenyl)-3-yl]-N,N,5,11-tetraphenyl-5,9-dihydro-5,9-diaza-13b-borataanthra[3,2,1-de]anthracen-3-amine (abbreviation: DABNA2), 2,12-di(tert-butyl)-5,9-bis(4-tert-butylphenyl)-N,N-diphenyl-5H,9H-[1,4]benzazaborolo[2,3,4-kl]phenazaborole-7-amine (abbreviation: DPhA-tBu4DABNA), 2,12-di(tert-butyl)-N,N,5,9-tetrakis(4-tert-butylphenyl)-5H,9H-[1,4]benzazaborolo[2,3,4-kl]phenazaborole-7-amine (abbreviation: tBuDPhA-tBu4DABNA), 2,12-di(tert-butyl)-5,9-bis(4-tert-butylphenyl)-7-methyl-5H,9H-[1,4]benzazaborolo[2,3,4-kl]phenazaborole (abbreviation: Me-tBu4DABNA), N 7 ,N 7 ,N 13 ,N 13, 5, 9, 11, 15 - octaphenyl - 5H, 9H, 11H, 15H - [1,4]benzazaborino[2,3,4 - kl][1,4]benzazaborino[4’,3’,2’:4,5][1,4]benzazaborino[3,2 - b]phenazaborine - 7,13 - diamine (abbreviation: ν - DABNA), 2 - (4 - tert - butylphenyl)benzo[5,6]indolo[3,2,1 - jk]benzo[b]carbazole (abbreviation: tBuPBibc), and other nitrogen - and boron - containing fused heteroaromatic compounds, especially compounds having a diaza - bora - naphtho - anthracene skeleton have a narrow - width emission spectrum and can thus obtain blue light emission with good color purity, and can therefore be used appropriately.

[0144] In addition to the above, 9,10,11 - tris[3,6 - bis(1,1 - dimethylethyl) - 9H - carbazol - 9 - yl] - 2,5,15,18 - tetra(1,1 - dimethylethyl)indolo[3,2,1 - de]indolo[3’,2’,1’:8,1][1,4]benzazaborino[2,3,4 - kl]phenazaborine (abbreviation: BBCz - G), 9,11 - bis[3,6 - bis(1,1 - dimethylethyl) - 9H - carbazol - 9 - yl] - 2,5,15,18 - tetra(1,1 - dimethylethyl)indolo[3,2,1 - de]indolo[3’,2’,1’:8,1][1,4]benzazaborino[2,3,4 - kl]phenazaborine (abbreviation: BBCz - Y), etc. can also be used appropriately.

[0145] When a phosphorescent light - emitting material is used as the light - emitting material in the light - emitting layer, examples of the materials that can be used are as follows.

[0146] Examples include: tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN2]phenyl-κC}iridium(III) (abbreviation: [Ir(mpptz-dmp)3]), tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazole)iridium(III) (abbreviation: [Ir(Mptz)3]) and other organometallic iridium complexes with a 4H-triazole backbone; tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazole]iridium(III) (abbreviation: [Ir(Mptz1-mp)3]), tris(1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazole)iridium(III) (abbreviation: [Ir(Prptz1-Me)3]) and other organometallic iridium complexes with a 1H-triazole backbone; fac-tris[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation: [Ir(iPrpim)3]), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: [Ir(dmpimpt-Me)3]), tris(2-{1-[2,6-bis(1-methylethyl)phenyl]-1H-imidazol-2-yl-κN3}-4-cyanophenyl-κC) (abbreviation: CNImIr) and other organometallic iridium complexes with an imidazole backbone; tris[(6-tert-butyl-3-phenyl-2H-imidazo[4,5-b]pyrazin-1-yl-κC2)phenyl-κC]iridium(III) (abbreviation: [Ir(cb)3]) and other organometallic complexes with a benzimidazolylidene backbone; and bis[2-(4’,6’-difluorophenyl)pyridinato-N,C 2’ iridium(III) tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4’,6’-difluorophenyl)pyridinato-N,C 2’ iridium(III) picolinate (abbreviation: FIrpic), bis{2-[3’,5’-bis(trifluoromethyl)phenyl]pyridinato-N,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)) and other organometallic iridium complexes with phenylpyridine derivatives having an electron-withdrawing group as ligands. The above substances are compounds that emit blue phosphorescence and are compounds having a luminescence peak in the wavelength region of 450 nm to 520 nm.

[0147] In addition, examples include: tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)3]), tris(4-tert-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-norbornanyl)-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)]) and other organometallic iridium complexes with a pyrimidine skeleton; (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)]) and other organometallic iridium complexes with a pyrazine skeleton; 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’)Organic metal iridium complexes with a pyridine skeleton such as iridium(III) acetylacetonate (abbreviation: [Ir(pq)2(acac)]), [2-d3-methyl-8-(2-pyridyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(5-d3-methyl-2-pyridyl-κN2)phenyl-κC]iridium(III) (abbreviation: [Ir(5mppy-d3)2(mbfpypy-d3)]), [2-d3-methyl-(2-pyridyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(2-pyridyl-κN)phenyl-κC]iridium(III) (abbreviation: [Ir(ppy)2(mbfpypy-d3)]), [2-(4-d3-methyl-5-phenyl-2-pyridyl-κN2)phenyl-κC]bis[2-(5-d3-methyl-2-pyridyl-κN2)phenyl-κC]iridium(III) (abbreviation: [Ir(5mppy-d3)2(mdppy-d3)]), [2-methyl-(2-pyridyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(2-pyridyl-κN)phenyl-κC]iridium(III) (abbreviation: [Ir(ppy)2(mbfpypy)]), [2-(4-methyl-5-phenyl-2-pyridyl-κN)phenyl-κC]bis[2-(2-pyridyl-κN)phenyl-κC]iridium(III) (abbreviation: [Ir(ppy)2(mdppy)]); and rare earth metal complexes such as tris(acetylacetonato)(monophenanthroline) terbium(III) (abbreviation: [Tb(acac)3(Phen)]). The above substances are mainly compounds that exhibit green phosphorescence and have a luminescence peak in the wavelength region of 500 nm to 600 nm. In addition, organic metal iridium complexes with a pyrimidine skeleton are particularly preferred because they have particularly excellent reliability or luminescence efficiency.

[0148] In addition, examples include: bis[4,6-bis(3-methylphenyl)pyrimidinato](dibenzoylmethanato)iridium(III) (abbreviation: [Ir(5mdppm)2(dibm)]), bis[4,6-bis(3-methylphenyl)pyrimidinato](di-neopentanoylmethanato)iridium(III) (abbreviation: [Ir(5mdppm)2(dpm)]), bis[4,6-bis(naphthalen-1-yl)pyrimidinato](di-neopentanoylmethanato)iridium(III) (abbreviation: [Ir(d1npm)2(dpm)]) and other organometallic iridium complexes having a pyrimidine skeleton; bis(2,3,5-triphenylpyrazinato)(acetylacetonato)iridium(III) (abbreviation: [Ir(tppr)2(acac)]), bis(2,3,5-triphenylpyrazinato)(di-neopentanoylmethanato)iridium(III) (abbreviation: [Ir(tppr)2(dpm)]), bis(acetylacetonato)[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq)2(acac)]) and other organometallic iridium complexes having a pyrazine skeleton; tris(1-phenylisoquinoline-N,C 2’ )iridium(III) (abbreviation: [Ir(piq)3]), bis(1-phenylisoquinoline-N,C 2’ )iridium(III) acetylacetonate (abbreviation: [Ir(piq)2(acac)]), (3,7-diethyl-4,6-nonanedionato-κO4,κO6)bis[2,4-dimethyl-6-[7-(1-methylethyl)-1-isoquinolinyl-κN]phenyl-κC]iridium(III), (3,7-diethyl-4,6-nonanedionato-κO4,κO6)bis[2,4-dimethyl-6-[5-(1-methylethyl)-2-quinolinyl-κN]phenyl-κC]iridium(III) and other organometallic iridium complexes having a pyridine skeleton; platinum complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: PtOEP); and rare earth metal complexes such as tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: [Eu(DBM)3(Phen)]), tris[1-(2-thienoyl)-3,3,3-trifluoroacetone](monophenanthroline)europium(III) (abbreviation: [Eu(TTA)3(Phen)]). The above substances are compounds that exhibit red phosphorescence and have a luminescence peak in the wavelength region of 600 nm to 700 nm. In addition, organometallic iridium complexes having a pyrazine skeleton can obtain red luminescence with good chromaticity.

[0149] In addition, in addition to the above phosphorescent compounds, known phosphorescent compounds can also be selected and used.

[0150] As TADF materials, fullerenes and their derivatives, acridine and its derivatives, eosin derivatives, etc. can be used. In addition, metal-containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), palladium (Pd), etc. can also be cited. As the metal-containing porphyrin, for example, 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. represented by the following structural formulas can also be cited.

[0151] [Chemical formula 6]

[0152] In addition, 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-dihydroacridin)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracene]-10'-one (abbreviation: ACRSA), etc., which have one or both of a heteroaromatic ring with rich π-electrons and a heteroaromatic ring with deficient π-electrons, can be used. This heteroaromatic compound has a heteroaromatic ring with rich π-electrons and a heteroaromatic ring with deficient π-electrons, and both have high electron transportability and hole transportability, so it is preferred. Among them, in the skeleton with a heteroaromatic ring with deficient π-electrons, the pyridine skeleton, diazine skeletons (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), and triazine skeleton are stable and have good reliability, so they are preferred. In particular, the benzofuranopyrimidine skeleton, benzothiophenopyrimidine skeleton, benzofuranopyrazine skeleton, and benzothiophenopyrazine skeleton have high electron acceptor properties and good reliability, so they are preferred. In addition, in the skeleton with a heteroaromatic ring with rich π-electrons, the acridine skeleton, phenoxazine skeleton, phenothiazine skeleton, furan skeleton, thiophene skeleton, and pyrrole skeleton are stable and have good reliability, so it is preferred to have at least one of the above skeletons. In addition, as the furan skeleton, a dibenzofuran skeleton is preferably used, and as the thiophene skeleton, a dibenzothiophene skeleton is preferably used. As the pyrrole skeleton, an indole skeleton, a carbazole skeleton, an indolecarbazole skeleton, a bicarbazole skeleton, and a 3-(9-phenyl-9H-carbazol-3-yl)-9H-carbazole skeleton are particularly preferably used. In a substance in which a heteroaromatic ring with rich π-electrons and a heteroaromatic ring with deficient π-electrons are directly bonded, both the electron-donating property of the heteroaromatic ring with rich π-electrons and the electron-accepting property of the heteroaromatic ring with deficient π-electrons are high, and the energy difference between the S1 energy level and the T1 energy level becomes smaller, so thermally activated delayed fluorescence can be obtained efficiently, so it is particularly preferred. Note that an aromatic ring bonded with an electron-withdrawing group such as a cyano group can also be used instead of the heteroaromatic ring with deficient π-electrons. In addition, as the rich π-electron skeleton, an aromatic amine skeleton, a phenazine skeleton, etc. can be used.In addition, as the π-deficient electron skeleton, an oxygen heterocycle 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 boranthrene, 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. Thus, at least one of the π-deficient electron skeleton and the π-rich electron skeleton can be used in place of the π-deficient electron heteroaromatic ring and the π-rich electron heteroaromatic ring.

[0153] [Chemical formula 7]

[0154] The TADF material refers to a material in which the energy difference between the S1 energy level and the T1 energy level is small and has the function of converting triplet excitation energy into singlet excitation energy through reverse intersystem crossing. Therefore, the triplet excitation energy can be up-converted into singlet excitation energy (reverse intersystem crossing) by a small amount of thermal energy and singlet excited states can be efficiently generated. In addition, the triplet excitation energy can be converted into light emission.

[0155] An exciplex formed by two substances in the excited state has the function of a TADF material that can convert triplet excitation energy into singlet excitation energy because the energy difference between the S1 energy level and the T1 energy level is extremely small.

[0156] Note that as an index of the T1 energy level, a phosphorescence spectrum observed at low temperature (for example, 77K to 10K) can be used. For TADF materials, preferably, when the wavelength energy of the extrapolated line obtained by drawing a tangent at the tail on the short wavelength side of the fluorescence spectrum is the S1 energy level and the wavelength energy of the extrapolated line obtained by drawing a tangent at the tail on the short wavelength side of the phosphorescence spectrum is the T1 energy level, the difference between S1 and T1 is 0.3 eV or less, more preferably 0.2 eV or less.

[0157] In addition, when a TADF material is used as the light-emitting substance, the S1 energy level of the host material is preferably higher than the S1 energy level of the TADF material. In addition, the T1 energy level of the host material is preferably higher than the T1 energy level of the TADF material.

[0158] As the host material of the light-emitting layer, various charge transport materials such as a material having electron transport properties and / or a material having hole transport properties, and the above-mentioned TADF materials can be used.

[0159] As the material having hole transporting property, an organic compound having an amine skeleton, a π-electron rich heteroaromatic ring skeleton, etc. is preferably used. As the π-electron rich heteroaromatic ring, a fused aromatic ring containing at least any one of an acridine skeleton, a phenoxazine skeleton, a phenothiazine skeleton, a furan skeleton, a thiophene skeleton, and a pyrrole skeleton is preferred, and specifically, a carbazole ring, a dibenzothiophene ring, or a ring in which these rings are further fused with an aromatic ring or a heteroaromatic ring is preferred.

[0160] Such an organic compound having hole transporting property preferably has any one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton. In particular, it can be an aromatic amine having a substituent including a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine including a naphthalene ring, or an aromatic monoamine in which 9-fluorenyl is bonded to the nitrogen of the amine through an arylene group. Note that when these organic compounds having hole transporting property are substances including N,N-bis(4-biphenyl)amino, a light-emitting device having a long lifetime can be manufactured, so they are preferred.

[0161] Examples of such organic compounds include: 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviation: TPD), N,N'-bis(9,9'-spirobi[9H-fluorene]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (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'-bis(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]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF), etc., compounds having an aromatic amine skeleton; 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-bis(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 9,9'-diphenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCCP), etc., compounds having a carbazole skeleton; 4,4',4''-(benzene-1,3,5-triyl)tris(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., compounds having a thiophene skeleton; and 4,4',4''-(benzene-1,3,5-triyl)tris(dibenzofuran) (abbreviation: DBF3P-II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II), etc., compounds having a furan skeleton. Among them, compounds having an aromatic amine skeleton and compounds having a carbazole skeleton have good reliability and high hole transportability and contribute to reducing the driving voltage, so they are preferred. In addition, organic compounds exemplified as examples of hole-transporting materials for the hole-transporting layer can also be used.

[0162] As the material having electron transporting property, for example, bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq2), bis(2-methyl-8-hydroxyquinolinato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), bis(8-hydroxyquinolinato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ) and other metal complexes, and organic compounds having π-deficient heteroaromatic rings are preferably used. As the organic compounds containing a heteroaromatic skeleton of the π-deficient type, for example, organic compounds containing a heteroaromatic ring having an oxazole skeleton, organic compounds containing a heteroaromatic ring having a pyridine skeleton, organic compounds containing a heteroaromatic ring having a diazine skeleton, and organic compounds containing a heteroaromatic ring having a triazine skeleton can be cited.

[0163] Among them, organic compounds containing a heteroaromatic ring having a diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), organic compounds containing a heteroaromatic ring having a pyridine skeleton, or organic compounds containing a heteroaromatic ring having a triazine skeleton have good reliability, and thus are preferred. In particular, organic compounds containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton and organic compounds containing a heteroaromatic ring having a triazine skeleton have high electron transporting property, which helps to reduce the driving voltage. In addition, benzofuranopyrimidine skeleton, benzothiophenopyrimidine skeleton, benzofuranopyrazine skeleton, and benzothiophenopyrazine skeleton have high electron accepting property and high reliability, and thus are preferred.

[0164] Examples of organic compounds having a π-electron-deficient heteroaromatic ring 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-[ Organic compounds having an azole skeleton, such as 3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviated as mDBTBIm-II), 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (abbreviated as BzOs); 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviated as 35DCzPPy), 1,3,5-tris[3-(3-pyridyl)phenyl]benzene (abbreviated as TmPyPB), bathophenanthroline (abbreviated as Bphen), bathocuproin (abbreviated as BCP), 2,9-di(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviated as NBphen), 2,2'-(1,3-phenylene)bis( Organic compounds containing a heteroaromatic ring having a pyridine skeleton, such as 2-[3-(2-triphenyl)phenyl]-1,10-phenanthroline (abbreviated as mPPhen2P), 2-[3-(2-triphenyl)phenyl]-1,10-phenanthroline (abbreviated as mTpPPhen), 2-phenyl-9-(2-triphenyl)-1,10-phenanthroline (abbreviated as Ph-TpPhen), 2-[4-(9-phenanthrenyl)-1-naphthyl]-1,10-phenanthroline (abbreviated as PnNPhen), and 2-[4-(2-triphenyl)phenyl]-1,10-phenanthroline (abbreviated as pTpPPhen); 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as 2mDBTPDB q-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as: 2mDBTBPDBq-II), 2-[3'-(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as: 2mCzBPDBq), 2-{3-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}dibenzo[f,h]quinoxaline (abbreviated as: 2mPCCzPDBq), 2-[4'-(9-phenyl-9H-carbazol-3-yl)-3,1'-biphenyl-1-yl]dibenzo[f,h]quinoxaline (abbreviated as: 2mpPCBPDBq), 2-[4-(3,6-Diphenyl-9H-carbazol-9-yl)phenyl]dibenzof[f,h]quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(Dibenzothiophen-4-yl)phenyl]dibenzof[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), 6-[3-(Dibenzothiophen-4-yl)phenyl]dibenzof[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 9-[3'-(Dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9mDBtBPNfpr), 9-[3'-(Dibenzothiophen-4-yl)biphenyl-4-yl]naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9pmDBtBPNfpr), 4,6-Bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-Bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6-Bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm), 9,9'-[Pyrimidine-4,6-diylbis(biphenyl-3,3'-diyl)]bis(9H-carbazole) (abbreviation: 4,6mCzBP2Pm), 8-(Biphenyl-4-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8BP-4mDBtPBfpm), 3,8-Bis[3-(dibenzothiophen-4-yl)phenyl]benzofuro[2,3-b]pyrazine (abbreviation: 3,8mDBtP2Bfpr), 4,8-Bis[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 4,8mDBtP2Bfpm), 8-[3'-(Dibenzothiophen-4-yl)(biphenyl-3-yl)]naphtho[1',2':4,5]furo[3,2-d]pyrimidine (abbreviation: 8mDBtBPNfpm), 8-[(2,2'-Binaphthalen)-6-yl]-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8(βN2)-4mDBtPBfpm), 2,2'-(Pyridine-2,6-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 2,6(P-Bqn)2Py), 2,2'-(Pyridine-2,6-diyl)bis{4-[4-(naphthalen-2-yl)phenyl]-6-phenylpyrimidine} (abbreviation: 2,6(NP-PPm)2Py), 6-(Biphenyl-3-yl)-4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), 2,6-Bis(4-naphthalen-1-ylphenyl)-4-[4-(pyridin-3-yl)phenyl]pyrimidine (abbreviation: 2,4NP-6PyPPm), 4-[3,5-bis(9H-carbazol-9-yl)phenyl]-2-phenyl-6-(biphenyl-4-yl)pyrimidine (abbreviation: 6BP-4Cz2PPm), 7-[4-(9-phenyl-9H-carbazol-2-yl)quinazolin-2-yl]-7H-dibenzo[c,g]carbazole (abbreviation: PC-cgDBCzQz) and other organic compounds with a diazine backbone; 2-(biphenyl-4-yl)-4-phenyl-6-(9,9'-spirobi[9H-fluorene]-2-yl)-1,3,5-triazine (abbreviation: BP-SFTzn), 2-{3-[3-(benzo[b]naphtho[1,2-d]furan-8-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mBnfBPTzn), 2-{3-[3-(benzo[b]naphtho[1,2-d]furan-6-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mBnfBPTzn-02), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 9-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTzn-02), 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFBPTzn), 5-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]carbazole (abbreviation: mINc(II)PTzn), 2-{3-[3-(dibenzothiophen-4-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mDBtBPTzn), 2,4,6-tris[3'-(pyridin-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviation: TmPPPyTz), 2-[3-(2,6-dimethyl-3-pyridyl)-5-(9-phenanthryl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mPn-mDMePyPTzn), 11-[4-(biphenyl-4-yl)-6-phenyl-1,3,5-triazin-2-yl]-11,12-dihydro-12-phenyl-indolo[2,3-a]carbazole (abbreviation: BP-Icz(II)Tzn), 2-[3'-(triphenylene-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mTpBPTzn), 3-[9-(4,6-diphenyl-1,3,5-(triazin-2-yl)-2-dibenzofuranyl]-9-phenyl-9H-carbazole (abbreviation: PCDBfTzn), 2-(biphenyl-3-yl)-4-phenyl-6-{8-[(1,1':4',1''-terphenyl)-4-yl]-1-dibenzofuranyl}-1,3,5-triazine (abbreviation: mBP-TPDBfTzn), 2-[4-(2-naphthyl)phenyl]-4-phenyl-6-spiro[9H-fluorene-9,9'-[9H]xanthene]-4-yl-1,3,5-triazine (abbreviation: βNP-SFx(4)Tzn), 2-phenyl-4,6-bis[3-(triphenylsilyl)phenyl]-1,3,5-triazine (abbreviation: mSiTrz), etc., which are organic compounds containing a heteroaromatic ring having a triazine skeleton. In addition, an organic compound containing a heteroaromatic ring having a diazine skeleton, an organic compound containing a heteroaromatic ring having a pyridine skeleton, or an organic compound containing a heteroaromatic ring having a triazine skeleton has high reliability, and thus is preferred. In particular, an organic compound containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton and an organic compound containing a heteroaromatic ring having a triazine skeleton have high electron transport properties, which helps to reduce the driving voltage.

[0165] As a TADF material that can be used as a host material, the same materials as those listed above as TADF materials can be used. When a TADF material is used as a host material, the triplet excitation energy generated by the TADF material is converted into singlet excitation energy through reverse intersystem crossing and further energy is transferred to the luminescent material, thereby improving the luminous efficiency of the light-emitting device. At this time, the TADF material is used as an energy donor and the luminescent material is used as an energy acceptor.

[0166] This is very effective when the above luminescent material is a fluorescent luminescent material. In addition, at this time, in order to obtain high luminous efficiency, the S1 energy level of the TADF material is preferably higher than the S1 energy level of the fluorescent luminescent material. In addition, the T1 energy level of the TADF material is preferably higher than the S1 energy level of the fluorescent luminescent material. Therefore, the T1 energy level of the TADF material is preferably higher than the T1 energy level of the fluorescent luminescent material.

[0167] In addition, it is preferable to use a TADF material that emits light with a wavelength overlapping the absorption band on the lowest energy side of the fluorescent luminescent material. Thereby, the excitation energy is smoothly transferred from the TADF material to the fluorescent luminescent material, and high-efficiency light emission can be obtained, so it is preferred.

[0168] In order to efficiently generate singlet excitation energy from triplet excitation energy through reverse intersystem crossing, it is preferable to generate carrier recombination in the TADF material. In addition, it is preferable that the triplet excitation energy generated in the TADF material does not transfer to the triplet excitation energy of the fluorescent emitter. For this purpose, the fluorescent emitter preferably has a protecting group around the emitter (the skeleton that causes luminescence) possessed by the fluorescent emitter. As this protecting group, a substituent without a π bond is preferable, and a saturated hydrocarbon is preferable. Specifically, an alkyl group having 3 or more and 10 or less carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 or more and 10 or less carbon atoms, or a trialkylsilyl group having 3 or more and 10 or less carbon atoms can be cited. More preferably, it has a plurality of protecting groups. Since the substituent without a π bond has almost no function of transporting carriers, it has almost no influence on carrier transport or carrier recombination, and can keep the emitter of the TADF material and the fluorescent emitter away from each other. Here, the emitter refers to the atomic group (skeleton) that causes luminescence in the fluorescent emitter. The emitter preferably has a skeleton with a π bond, preferably contains an aromatic ring, and preferably has a fused aromatic ring or a fused heteroaromatic ring. As the above-mentioned emitter, for example, a phenanthrene skeleton, a stilbene skeleton, an acridone skeleton, a phenoxazine skeleton, a phenothiazine skeleton, a naphthalene skeleton, an anthracene skeleton, a fluorene skeleton, a skeleton, a triphenylene skeleton, a tetracene skeleton, a pyrene skeleton, a perylene skeleton, a coumarin skeleton, a quinacridone skeleton, a naphthobisbenzofuran skeleton, etc. In particular, fluorescent emitters having a naphthalene skeleton, an anthracene skeleton, a fluorene skeleton, a skeleton, a triphenylene skeleton, a tetracene skeleton, a pyrene skeleton, a perylene skeleton, a coumarin skeleton, a quinacridone skeleton, a naphthobisbenzofuran skeleton have a high fluorescence quantum yield, so they are preferable.

[0169] In the case where a fluorescent luminescent substance is used as the luminescent substance, as the host material, a material having an anthracene skeleton is preferably used. By using a substance having an anthracene skeleton as the host material of the fluorescent luminescent substance, a luminescent layer with high luminous efficiency and durability can be achieved. Among the substances having an anthracene skeleton used as the host material, substances having a diphenylanthracene skeleton, especially a 9,10-diphenylanthracene skeleton, are chemically stable, so they are preferred. In addition, when the host material has a carbazole skeleton, the hole injection / transport property is improved, so it is preferred. In the case of including a benzocarbazole skeleton in which a benzene ring is fused to carbazole, its HOMO level is about 0.1 eV higher than that when including a carbazole skeleton, and holes are easily injected, so it is more preferred. In particular, when the host material has a dibenzocarbazole skeleton, its HOMO level is about 0.1 eV higher than that when including a carbazole skeleton, and not only are holes easily injected, but also the hole transport property and heat resistance are improved, so it is preferred. Therefore, a substance further preferably used as the host material is a substance having a 9,10-diphenylanthracene skeleton and a carbazole skeleton (or a benzocarbazole skeleton or a dibenzocarbazole skeleton). Note that from the above viewpoint of hole injection / transport property, a benzofluorene skeleton or a dibenzofluorene skeleton can also be used instead of the carbazole skeleton. Examples of such substances 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-anthryl)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), 9-(1-naphthyl)-10-(2-naphthyl)anthracene (abbreviation: α,βADN), 2-(10-phenylanthracen-9-yl)dibenzofuran, 2-(10-phenyl-9-anthryl)-benzo[b]naphtho[2,3-d]furan (abbreviation: Bnf(II)PhA), 9-(2-naphthyl)-10-[3-(2-naphthyl)phenyl]anthracene (abbreviation: βN-mβNPAnth), 1-{4-[10-(biphenyl-4-yl)-9-anthryl]phenyl}-2-ethyl-1H-benzimidazole (abbreviation: EtBImPBPhA), etc. In particular, CzPA, cgDBCzPA, 2mBnfPPA, and PCzPA exhibit very good properties, so they are preferred.

[0170] In addition, the host material may also be a material that mixes multiple substances. When using a mixed host material, it is preferable to mix a material with electron-transporting properties and a material with hole-transporting properties. By mixing a material with electron-transporting properties and a material with hole-transporting properties, it becomes easier to adjust the transport properties of the light-emitting layer 113, and it is also possible to more simply control the recombination region. The weight ratio of the content of the material with hole-transporting properties to the content of the material with electron-transporting properties may be from 1:19 to 19:1.

[0171] Note that, as part of the above-mentioned mixed materials, a phosphorescent light-emitting substance may be used. The phosphorescent light-emitting substance can be used as an energy donor that supplies excitation energy to the fluorescent light-emitting substance when the fluorescent light-emitting substance is used as the light-emitting substance.

[0172] In addition, these mixed materials may also be used to form an exciplex. By selecting the mixed materials in such a way as to form an exciplex that emits light with a wavelength overlapping the absorption band on the lowest energy side of the light-emitting substance, energy transfer can be made smooth, and thus light emission can be obtained efficiently, so it is preferable. In addition, by adopting this structure, the driving voltage can be reduced, so it is preferable.

[0173] Note that at least any one of the materials forming the exciplex may be a phosphorescent light-emitting substance. Thereby, triplet excitation energy can be efficiently converted into singlet excitation energy through reverse intersystem crossing.

[0174] Regarding the combination of materials for efficiently forming an exciplex, the HOMO level of the material with hole-transporting properties is preferably higher than the HOMO level of the material with electron-transporting properties. In addition, the LUMO level of the material with hole-transporting properties is preferably higher than the LUMO level of the material with electron-transporting properties. Note that the LUMO level and HOMO level of the material can be obtained from the electrochemical characteristics (reduction potential and oxidation potential) of the material measured by cyclic voltammetry (CV) measurement.

[0175] Note that the formation of an exciplex can be confirmed, for example, by comparing the emission spectra of a hole-transporting material, the emission spectra of an electron-transporting material, and the emission spectra of a mixed film formed by mixing these materials. When it is observed that the emission spectrum of the mixed film is shifted to the longer wavelength side (or has a new peak on the longer wavelength side) compared to the emission spectra of the respective materials, it indicates the formation of an exciplex. Alternatively, by comparing the transient photoluminescence (PL) of a hole-transporting material, the transient PL of an electron-transporting material, and the transient PL of a mixed film formed by mixing these materials, when it is observed that the transient PL lifetime of the mixed film has a long-lived component or the ratio of the delayed component becomes larger compared to the transient PL lifetimes of the respective materials, it indicates the formation of an exciplex. In addition, the above transient PL can be referred to as transient electroluminescence (EL). In other words, by comparing the transient EL of a hole-transporting material, the transient EL of an electron-transporting material, and the transient EL of a mixed film of these materials, and observing the difference in the transient response, the formation of an exciplex can be confirmed.

[0176] The electron transport layer 114 is a layer containing a substance having electron transport properties. As the material having electron transport properties, it is preferably a substance having an electron mobility of 1×10 -7 cm 2 / Vs or more, preferably 1×10 -6 cm 2 / Vs or more when the square root of the electric field strength [V / cm] is 600. In addition, as long as the substance has higher electron transport properties than hole transport properties, substances other than the above can also be used. As the above organic compound, an organic compound having a π-deficient heteroaromatic ring is preferably used. As the organic compound containing a π-deficient heteroaromatic ring, for example, an organic compound containing a heteroaromatic ring having an oxazole skeleton, an organic compound containing a heteroaromatic ring having a pyridine skeleton, an organic compound containing a heteroaromatic ring having a diazine skeleton, and an organic compound containing a heteroaromatic ring having a triazine skeleton, one or more of them are preferably used.

[0177] As the organic compound having electron-transporting properties that can be used in the above-described electron-transporting layer 114, the organic compound having electron-transporting properties in the above-described light-emitting layer 113 and the organic compounds exemplified as the second organic compound that can be used in the electron-injecting layer 115 in Embodiment 1 can be similarly used. Among them, organic compounds containing a heteroaromatic ring having a diazine skeleton, organic compounds containing a heteroaromatic ring having a pyridine skeleton, and organic compounds containing a heteroaromatic ring having a triazine skeleton have good reliability, and thus are preferred. In particular, organic compounds containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton and organic compounds containing a heteroaromatic ring having a triazine skeleton have high electron-transporting properties, which helps to reduce the driving voltage. In particular, organic compounds having a phenanthroline skeleton such as mTpPPhen, PnNPhen, and mPPhen2P are preferred, and organic compounds having a phenanthroline dimer structure such as mPPhen2P have excellent stability, and thus are more preferred. In addition, it is preferable to use organic compounds having electron-transporting properties and a high HOMO level such as 2mPCCzPDBq and DACT-II, whereby a light-emitting device with a low driving voltage can be obtained.

[0178] In addition, the electron-transporting layer preferably contains an organic compound having electron-transporting properties with an acidity coefficient pKa of less than 4.

[0179] Note that the electron-transporting layer 114 may also have a stacked structure. In addition, when the electron-transporting layer 114 has a stacked structure, the layer in contact with the light-emitting layer 113 may also be used as a hole-blocking layer. When the electron-transporting layer in contact with the light-emitting layer is used as a hole-blocking layer, it is preferable to use a material whose HOMO level is 0.5 eV or more lower than the HOMO level of the material contained in the light-emitting layer.

[0180] An electron-injecting layer 115 is formed between the electron-transporting layer 114 and the second electrode 102. The structure of the electron-injecting layer 115 has been described in detail in Embodiment 1, and thus repeated description is omitted.

[0181] The second electrode 102 is an electrode including a cathode. The second electrode 102 may also have a stacked structure. In this case, the layer in contact with the organic compound layer 103 is used as the cathode. As the material for forming the cathode, metals, alloys, conductive compounds, and mixtures thereof with a small work function (specifically, 3.8 eV or less) can be used. Specific examples of such cathode materials include alkali metals such as lithium (Li) or cesium (Cs), elements belonging to Group 1 or Group 2 of the periodic table such as magnesium (Mg), calcium (Ca), or strontium (Sr), alloys containing them (MgAg, AlLi), compounds (lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), etc.), rare earth metals such as europium (Eu) and ytterbium (Yb), and alloys containing them. However, by providing an electron injection layer 115 or a thin film of the above-mentioned material with a small work function between the second electrode 102 and the electron transport layer, various conductive materials such as Al, Ag, ITO, indium tin oxide containing silicon or silicon oxide, etc. can be used as the cathode regardless of the work function size.

[0182] When the second electrode 102 is made of a material having transparency to visible light, a light-emitting device that emits light from the second electrode 102 side can be formed. When the first electrode 101 is made of a material having transparency to visible light, a light-emitting device that emits light from the first electrode 101 side can be formed.

[0183] These conductive materials can be formed by dry methods such as vacuum evaporation and sputtering, inkjet methods, spin coating methods, etc. In addition, they can also be formed by wet methods such as sol-gel methods or wet methods using pastes of metal materials.

[0184] In addition, when it is a top-emission type light-emitting device, the light extraction efficiency can be improved by evaporating an organic compound on the second electrode to form a cover layer. The cover layer can be a single-layer structure or a stacked structure. When it is a stacked structure, the light extraction efficiency can be further improved by using organic compounds with different refractive indices respectively.

[0185] In addition, as a method for forming the organic compound layer 103, various methods can be used regardless of dry methods or wet methods. For example, vacuum evaporation, gravure printing, offset printing, screen printing, inkjet methods, spin coating methods, etc. can also be used.

[0186] In addition, the above-mentioned respective electrodes or layers can also be formed by using different deposition methods.

[0187] Next, with reference to Figure 1B The manner of a light-emitting device having a structure in which a plurality of light-emitting units are stacked (also referred to as a stacked device or a tandem device) will be described. This light-emitting device is a light-emitting device having a plurality of light-emitting units between an anode and a cathode. One light-emitting unit has a structure withFigure 1A The organic compound layer 103 shown has substantially the same structure. That is to say, it can be said that Figure 1B the light-emitting device shown is a light-emitting device having a plurality of light-emitting units, while Figure 1A the light-emitting device shown is a light-emitting device having one light-emitting unit.

[0188] In Figure 1B , a first light-emitting unit 511 and a second light-emitting unit 512 are stacked between a first electrode 501 and a second electrode 502, and an intermediate layer 513 is provided between the first light-emitting unit 511 and the second light-emitting unit 512. The first electrode 501 and the second electrode 502 respectively correspond to Figure 1A the first electrode 101 and the second electrode 102 in Figure 1A , and the same materials as those described in

[0189] The intermediate layer 513 has a function of injecting electrons into one light-emitting unit and injecting holes into the other light-emitting unit when a voltage is applied to the first electrode 501 and the second electrode 502. That is to say, in Figure 1B , when a voltage is applied in such a way that the potential of the anode is higher than the potential of the cathode, the intermediate layer 513 may be a layer that injects electrons into the first light-emitting unit 511 and injects holes into the second light-emitting unit 512.

[0190] The intermediate layer 513 includes a charge generation layer. In addition, the charge generation layer at least includes a P-type layer 117. The P-type layer 117 is preferably formed using the composite material that constitutes the hole injection layer 111 described above. In addition, the P-type layer 117 may also be formed by laminating a film containing the electron acceptor material and a film containing the hole transport material as the materials that constitute the composite material. By applying a potential to the P-type layer 117, electrons and holes are respectively injected into the electron transport layer 114 and the cathode, causing the light-emitting device to operate.

[0191] In addition, the intermediate layer 513 preferably further includes one or both of an electron relay layer 118 and an N-type layer 119 in addition to the P-type layer 117.

[0192] The electron relay layer 118 contains at least a substance with electron-transporting properties, can prevent the interaction between the N-type layer 119 and the P-type layer 117, and can transfer electrons smoothly. Preferably, the LUMO energy level of the substance with electron-transporting properties contained in the electron relay layer 118 is set between the LUMO energy level of the electron-accepting substance in the P-type layer 117 and the LUMO energy level of the substance contained in the layer in the electron transport layer 114 that contacts the intermediate layer 513. Specifically, the LUMO energy level of the substance with electron-transporting properties in the electron relay layer 118 is -5.0 eV or more, preferably -5.0 eV or more and -3.0 eV or less. In addition, as the substance with electron-transporting properties in the electron relay layer 118, a phthalocyanine material or a metal complex having a metal-oxygen bond and an aromatic ligand is preferably used.

[0193] For the N-type layer 119, substances with high electron-injecting properties such as alkali metals, alkaline earth metals, rare earth metals, and compounds of these substances (alkali metal compounds (including oxides such as lithium oxide, halides, carbonates such as lithium carbonate and cesium carbonate), alkaline earth metal compounds (including oxides, halides, carbonates), or compounds of rare earth metals (including oxides, halides, carbonates)) can be used.

[0194] In addition, when the N-type layer 119 contains a substance with electron-transporting properties and a donor substance, as the donor substance, in addition to alkali metals, alkaline earth metals, rare earth metals, and compounds of these substances (alkali metal compounds (including oxides such as lithium oxide, halides, carbonates such as lithium carbonate and cesium carbonate), alkaline earth metal compounds (including oxides, halides, carbonates), or compounds of rare earth metals (including oxides, halides, carbonates)), organic compounds such as tetrathianaphthacene (abbreviation: TTN), nickelocene, and decamethylnickelocene can also be used. In addition, as the substance with electron-transporting properties, the same materials as those described above for the electron transport layer 114 can be used.

[0195] Alternatively, a mixed layer including an organic compound having a phenanthroline skeleton with an electron-donating group, an organic compound containing a metal or a metal oxide and including a π-deficient heteroaromatic ring, which is described in Embodiment 1, can be formed at the same position as the N-type layer 119 instead of the N-type layer 119. When adopting this structure, a tandem light-emitting device with good characteristics can also be manufactured.

[0196] When the surface on the anode side of the light-emitting unit is in contact with the intermediate layer 513, the charge generation layer of the intermediate layer 513 can also function as the hole injection layer of the light-emitting unit, so the light-emitting unit may not be provided with a hole injection layer. When the surface on the cathode side of the light-emitting unit is in contact with the intermediate layer 513, the intermediate layer 513 can also function as the electron injection layer of the light-emitting unit, so the light-emitting unit may not be provided with an electron injection layer.

[0197] Although a light-emitting device having two light-emitting units is described in Figure 1B a light-emitting device in which three or more light-emitting units are stacked can be similarly applied. As the light-emitting device according to the present embodiment, by separating and arranging a plurality of light-emitting units using the intermediate layer 513 between a pair of electrodes, an element can be realized which can achieve high-brightness light emission while maintaining a low current density and has a long lifespan. In addition, a light-emitting device capable of low-voltage driving and low power consumption can be realized.

[0198] In addition, by making the light-emitting colors of the respective light-emitting units different, light emission of a desired color can be obtained for the entire light-emitting device. For example, by obtaining red and green light-emitting colors from a first light-emitting unit and a blue light-emitting color from a second light-emitting unit in a light-emitting device having two light-emitting units, a light-emitting device that emits white light throughout the light-emitting device can be obtained.

[0199] In addition, each layer and electrode such as the above-mentioned organic compound layer 103, the first light-emitting unit 511, the second light-emitting unit 512, and the intermediate layer 513 can be formed by methods such as evaporation (including vacuum evaporation), droplet ejection (also called inkjet), coating, gravure printing, etc. In addition, it can also include low molecular materials, medium molecular materials (including oligomers, dendrimers), or high molecular materials.

[0200] Figure 2A is a diagram of two adjacent light-emitting devices (light-emitting device 130a, light-emitting device 130b) included in a display device according to one aspect of the present invention.

[0201] The light-emitting device 130a includes an organic compound layer 103a between a first electrode 101a on an insulating layer 175 and a second electrode 102 opposite to the first electrode 101a. Although the organic compound layer 103a is shown to have a structure including a hole injection layer 111a, a hole transport layer 112a, a light-emitting layer 113a, an electron transport layer 114a, and an electron injection layer 115a, the organic compound layer 103a may also have a stacked structure different from the above structure.

[0202] The light-emitting device 130b includes an organic compound layer 103b between a first electrode 101b on an insulating layer 175 and a second electrode 102 opposite to the first electrode 101b. Although the organic compound layer 103b is shown to have a structure including a hole injection layer 111b, a hole transport layer 112b, a light-emitting layer 113b, an electron transport layer 114b, and an electron injection layer 115b, the organic compound layer 103b may also have a stacked structure different from the above structure.

[0203] The structures of the electron transport layer 114a and the electron injection layer 115a in the light-emitting device 130a and the structures of the electron transport layer 114b and the electron injection layer 115b in the light-emitting device 130b are preferably the structures described in Embodiment 1.

[0204] The second electrode 102 is preferably a continuous layer shared by the light-emitting device 130a and the light-emitting device 130b. In addition, the organic compound layer 103a and the organic compound layer 103b are processed by photolithography after forming the electron injection layer 115a and after forming the electron injection layer 115b, respectively, so they are independent of each other. A light-emitting device according to one embodiment of the present invention can obtain a light-emitting device with good characteristics even if it is processed by photolithography after forming the electron injection layer 115a and after forming the electron injection layer 115b, respectively. In addition, as Figure 3A shown, the electron injection layer 115a and the electron injection layer 115b may also be a continuous layer shared by the light-emitting device 130a and the light-emitting device 130b.

[0205] In addition, the end portions (contours) of the organic compound layer 103a are processed by photolithography, so they are substantially consistent in the direction perpendicular to the substrate. In addition, the end portions (contours) of the organic compound layer 103b are processed by photolithography, so they are substantially consistent in the direction perpendicular to the substrate.

[0206] In addition, due to the processing by photolithography, there is a gap d between the organic compound layer 103a and the organic compound layer 103b. In addition, by processing the EL layer by photolithography, the distance between the first electrode 101a and the first electrode 101b can be made smaller than that distance during mask evaporation, and it can be 0.5 μm or more and 5 μm or less.

[0207] Figure 2B is a diagram of two adjacent series-connected light-emitting elements (light-emitting devices 130c, 130d) manufactured by photolithography.

[0208] The light-emitting device 130c includes an organic compound layer 103c between the first electrode 101c and the second electrode on the insulating layer 175. The organic compound layer 103c has a structure in which the first light-emitting unit 501c and the second light-emitting unit 502c are stacked with the intermediate layer 116c therebetween. Note that, although Figure 2B an example of stacking two light-emitting units is shown, three or more light-emitting units may also be stacked. The first light-emitting unit 501c includes a hole injection layer 111c, a first hole transport layer 112c_1, a first light-emitting layer 113c_1, and a first electron transport layer 114c_1. The intermediate layer 116c includes a P-type layer 117c, an electron relay layer 118c, and an N-type layer 119c. Regardless of the presence or absence of the electron relay layer 118c. The second light-emitting unit 502c includes a second hole transport layer 112c_2, a second light-emitting layer 113c_2, a second electron transport layer 114c_2, and an electron injection layer 115c.

[0209] The light-emitting device 130d includes an organic compound layer 103d between the first electrode 101d and the second electrode on the insulating layer 175. The organic compound layer 103d has a structure in which the first light-emitting unit 501d and the second light-emitting unit 502d are stacked with the intermediate layer 116d therebetween. Note that, although Figure 2B an example of stacking two light-emitting units is shown, three or more light-emitting units may also be stacked. The first light-emitting unit 501d includes a hole injection layer 111d, a first hole transport layer 112d_1, a first light-emitting layer 113d_1, and a first electron transport layer 114d_1. The intermediate layer 116d includes a P-type layer 117d, an electron relay layer 118d, and an N-type layer 119d. Regardless of the presence or absence of the electron relay layer 118d. The second light-emitting unit 502d includes a second hole transport layer 112d_2, a second light-emitting layer 113d_2, a second electron transport layer 114d_2, and an electron injection layer 115d.

[0210] In the light-emitting device 130c and the light-emitting device 130d, the electron injection layers 115c and 115d preferably have the structures described in Embodiment 1.

[0211] The second electrode 102 is preferably a continuous layer shared by the light-emitting device 130c and the light-emitting device 130d. In addition, since the organic compound layer 103c and the organic compound layer 103d are processed by photolithography after forming the electron injection layer 115c and after forming the electron injection layer 115d, respectively, they are independent of each other. A light-emitting device according to one aspect of the present invention can obtain a light-emitting device having good characteristics even when processed by photolithography after forming the electron injection layer 115c and after forming the electron injection layer 115d, respectively. In addition, as Figure 3BAs shown, the electron injection layers 115c and 115d may also be continuous layers shared by the light-emitting devices 130c and 130d.

[0212] In addition, the end portions (contours) of the organic compound layer 103c are processed by photolithography, so they are substantially aligned in the direction perpendicular to the substrate. In addition, the end portions (contours) of the organic compound layer 103d are processed by photolithography, so they are substantially aligned in the direction perpendicular to the substrate.

[0213] In addition, due to the processing by photolithography, there is a gap d between the organic compound layer 103c and the organic compound layer 103d. In addition, by processing the EL layer by photolithography, the distance between the first electrodes 101c and 101d can be made smaller than that distance during mask evaporation, and it can be 0.5 μm or more and 5 μm or less.

[0214] The light-emitting device according to one embodiment of the present invention processes the organic compound layer by photolithography, and can be processed with sufficient precision, thereby enabling the manufacture of a high-definition display device. In addition, since the photolithography process can be performed on the electron injection layer far from the light-emitting layer without being contaminated by alkali metals, a light-emitting device with good characteristics can be realized. As described above, the light-emitting device according to one embodiment of the present invention having the above structure can realize a high-definition display device and a light-emitting device with good characteristics.

[0215] In addition, since the organic compound layers of the light-emitting device according to one embodiment of the present invention are processed simultaneously by photolithography, the contours of the layers included in the organic compound layer are substantially aligned. Here, "substantially aligned" in this specification means that the difference between the contour A of layer A and the contour B of layer B included in the organic compound layer is within 5% of the width of the organic compound layer on the line perpendicular to the contour of the part being compared. In addition, when the end face of the organic compound layer is in a tapered shape, continuous change of the contour is allowed.

[0216] The structure of this embodiment can be used in appropriate combination with other structures.

[0217] Embodiment 3 As Figure 4A and Figure 4B shown, a plurality of light-emitting devices 130 are formed on the insulating layer 175 to constitute a display device. In this embodiment, a display device according to one embodiment of the present invention will be described in detail.

[0218] The display device 100 includes a pixel portion 177 in which a plurality of pixels 178 are arranged in a matrix. The pixel 178 includes a sub-pixel 110R, a sub-pixel 110G, and a sub-pixel 110B.

[0219] In this specification and the like, sometimes, for example, the term "sub-pixel 110" is used to describe the common content among sub-pixel 110R, sub-pixel 110G, and sub-pixel 110B. In addition, regarding other components differentiated by letters, sometimes the reference numerals omitting the letters are used to describe the common content among those components.

[0220] Sub-pixel 110R emits red light, sub-pixel 110G emits green light, and sub-pixel 110B emits blue light. Thus, an image can be displayed on pixel section 177. Note that, in the present embodiment, sub-pixels of three colors, red (R), green (G), and blue (B), are taken as an example for description, and sub-pixels of other colors can also be combined. In addition, the number of sub-pixels is not limited to three and can also be four or more. As four sub-pixels, for example, sub-pixels of four colors, R, G, B, and white (W); sub-pixels of four colors, R, G, B, and Y; and sub-pixels of four colors, R, G, B, and infrared light (IR) can be cited; and so on.

[0221] In this specification and the like, sometimes the row direction is denoted as the X direction and the column direction is denoted as the Y direction. The X direction intersects with the Y direction, for example, perpendicularly.

[0222] In Figure 4A In the example shown, sub-pixels of different colors are arranged and configured in the X direction, and sub-pixels of the same color are arranged and configured in the Y direction. Note that sub-pixels of different colors can also be arranged and configured in the Y direction, and sub-pixels of the same color can be arranged and configured in the X direction.

[0223] A connection section 140 is provided outside pixel section 177, and an area 141 can also be provided. For example, area 141 is provided between pixel section 177 and connection section 140. An organic compound layer 103 is provided in area 141. In addition, a conductive layer 151C is provided in connection section 140.

[0224] In Figure 4A In the example shown, area 141 and connection section 140 are located on the right side of pixel section 177, but there is no particular limitation on the positions of area 141 and connection section 140. In addition, area 141 and connection section 140 can also be one or more.

[0225] Figure 4B is an example of a cross-sectional view along the dash-dot line A1 - A2 in Figure 4A As Figure 4BAs shown, the display device 100 includes an insulating layer 171, a conductive layer 172 on the insulating layer 171, an insulating layer 173 on the insulating layer 171 and the conductive layer 172, an insulating layer 174 on the insulating layer 173, and an insulating layer 175 on the insulating layer 174. The insulating layer 171 is disposed on a substrate (not shown). The insulating layer 175, the insulating layer 174, and the insulating layer 173 are provided with openings reaching the conductive layer 172, and plugs 176 are disposed in such a manner as to be embedded in the openings.

[0226] In the pixel portion 177, a light-emitting device 130 is disposed on the insulating layer 175 and the plugs 176. A protective layer 131 is disposed so as to cover the light-emitting device 130. The substrate 120 is bonded to the protective layer 131 by a resin layer 122. In addition, it is preferable to provide an inorganic insulating layer 125 and an insulating layer 127 on the inorganic insulating layer 125 between adjacent light-emitting devices 130.

[0227] Figure 4B Cross-sections of a plurality of inorganic insulating layers 125 and a plurality of insulating layers 127 are shown, but when looking down on the display device 100, the inorganic insulating layer 125 and the insulating layer 127 are preferably formed as continuous single layers, respectively. That is, the inorganic insulating layer 125 and the insulating layer 127 are preferably insulating layers having openings in the first electrode.

[0228] Figure 4B Light-emitting devices 130R, 130G, and 130B are shown as the light-emitting device 130. The light-emitting colors of the light-emitting devices 130R, 130G, and 130B are different from each other. For example, the light-emitting device 130R can emit red light, the light-emitting device 130G can emit green light, and the light-emitting device 130B can emit blue light. In addition, the light-emitting device 130R, the light-emitting device 130G, or the light-emitting device 130B can also emit other visible light or infrared light.

[0229] A display device according to one embodiment of the present invention may have, for example, a top emission structure that emits light in a direction opposite to the substrate on which the light-emitting device is formed. In addition, a display device according to one embodiment of the present invention may also have a bottom emission structure.

[0230] Examples of the light-emitting substance contained in the light-emitting device 130 include organic compounds or organometallic complexes such as substances that emit fluorescence (fluorescent materials), substances that emit phosphorescence (phosphorescent materials), and substances that exhibit thermally activated delayed fluorescence (thermally activated delayed fluorescence (TADF) materials). In addition, inorganic compounds such as quantum dots can also be used.

[0231] The light-emitting device 130R has the structure shown in Embodiment 1, including a first electrode (pixel electrode) composed of a conductive layer 151R and a conductive layer 152R, an organic compound layer 103R on the first electrode, a common layer 104 on the organic compound layer 103R, and a second electrode (common electrode) 102 on the common layer 104. The common layer 104 may or may not be provided. However, when the common layer 104 is provided, damage to the organic compound layer 103R during processing can be reduced, so it is preferred. When the common layer 104 is provided, the common layer 104 is preferably an electron injection layer. In addition, when the common layer 104 is provided, the stacked structure of the organic compound layer 103R and the common layer 104 corresponds to the organic compound layer 103 in Embodiment 2.

[0232] The light-emitting device 130G has the structure shown in Embodiment 1, including a first electrode (pixel electrode) composed of a conductive layer 151G and a conductive layer 152G, an organic compound layer 103G on the first electrode, a common layer 104 on the organic compound layer 103G, and a second electrode (common electrode) 102 on the common layer 104. The common layer 104 may or may not be provided. However, when the common layer 104 is provided, damage to the organic compound layer 103G during processing can be reduced, so it is preferred. When the common layer 104 is provided, the common layer 104 is preferably an electron injection layer. In addition, when the common layer 104 is provided, the stacked structure of the organic compound layer 103G and the common layer 104 corresponds to the organic compound layer 103 in Embodiment 2.

[0233] The light-emitting device 130B has the structure shown in Embodiment 1, including a first electrode (pixel electrode) composed of a conductive layer 151B and a conductive layer 152B, an organic compound layer 103B on the first electrode, a common layer 104 on the organic compound layer 103B, and a second electrode (common electrode) 102 on the common layer 104. The common layer 104 may or may not be provided. However, when the common layer 104 is provided, damage to the organic compound layer 103B during processing can be reduced, so it is preferred. When the common layer 104 is provided, the common layer 104 is preferably an electron injection layer. In addition, when the common layer 104 is provided, the stacked structure of the organic compound layer 103B and the common layer 104 corresponds to the organic compound layer 103 in Embodiment 2.

[0234] One of the pixel electrode and the common electrode included in the light-emitting device is used as the anode, and the other is used as the cathode. Hereinafter, unless otherwise specified, the description will be made on the premise that the pixel electrode is used as the anode and the common electrode is used as the cathode.

[0235] The organic compound layers 103R, 103G, and 103B are independently formed in an island shape for each light-emitting device or for each light-emitting color. By forming the organic compound layer 103 in an island shape for each light-emitting device 130, leakage current between adjacent light-emitting devices 130 can also be suppressed in the high-definition display device. As a result, crosstalk can be suppressed, and a display device with extremely high contrast can be realized. In particular, a display device with high current efficiency at low brightness can be realized.

[0236] The island-shaped organic compound layer 103 is formed by depositing an EL film and processing the EL film using a lithography technique.

[0237] In addition, in the display device according to one embodiment of the present invention, the first electrode (pixel electrode) of the light-emitting device preferably has a stacked structure. For example, in Figure 4B the example shown, the first electrode of the light-emitting device 130 has a stacked structure of a conductive layer 151 and a conductive layer 152. For example, when the display device 100 has a top emission structure and the pixel electrode of the light-emitting device 130 is used as an anode, it is preferable that the conductive layer 151 is a layer with a high visible light reflectance, and the conductive layer 152 is, for example, a layer with visible light transmissivity and a large work function. When the display device 100 has a top emission structure, the higher the visible light reflectance of the pixel electrode, the higher the light extraction efficiency of the light emitted from the organic compound layer 103. In addition, when the pixel electrode is used as an anode, the larger the work function of the pixel electrode, the easier it is to inject holes into the organic compound layer 103. As a result, by the pixel electrode of the light-emitting device 130 having a stacked structure of a conductive layer 151 with a high visible light reflectance and a conductive layer 152 with a large work function, the light-emitting device 130 can be a light-emitting device with high light extraction efficiency and low driving voltage.

[0238] When the conductive layer 151 is a layer with a high visible light reflectance, the visible light reflectance of the conductive layer 151 is, for example, preferably 40% or more and 100% or less, or 70% or more and 100% or less. In addition, when the conductive layer 152 is an electrode with visible light transmissivity, the visible light transmittance is, for example, preferably 40% or more.

[0239] Here, when the pixel electrode has a stacked structure of multiple layers, the pixel electrode is deteriorated, for example, due to the reaction between the multiple layers. For example, when the film formed after forming the pixel electrode is removed by a wet etching method, galvanic corrosion occurs due to the liquid medicine contacting the pixel electrode.

[0240] In view of this, in the display device 100 of the present embodiment, an insulating layer 156 is formed so as to cover the side surfaces of the conductive layer 151 and the conductive layer 152. Thereby, for example, even when removing the film formed after forming the pixel electrode including the conductive layer 151 and the conductive layer 152 by using a wet etching method, it is possible to suppress the chemical solution from contacting the conductive layer 151. Therefore, for example, it is possible to suppress the occurrence of galvanic corrosion in the pixel electrode. Therefore, the display device 100 can be manufactured by a method with a high yield, so that an inexpensive display device can be realized. In addition, it is possible to suppress the occurrence of defects in the display device 100, so that the display device 100 can be a highly reliable display device.

[0241] As the conductive layer 151, for example, a metal material can be used. Specifically, for example, metals such as aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), neodymium (Nd), etc. and alloys obtained by appropriately combining them can also be used.

[0242] As the conductive layer 152, an oxide containing one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon can be used. For example, a conductive oxide containing one or more of indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, zinc oxide containing gallium, titanium oxide, indium zinc oxide containing gallium, indium zinc oxide containing aluminum, indium tin oxide containing silicon, and indium zinc oxide containing silicon is preferably used. In particular, the indium tin oxide containing silicon has a relatively large work function, and its work function is, for example, 4.0 eV or more, so it can be suitably used as the conductive layer 152.

[0243] The conductive layer 151 and the conductive layer 152 may each have a laminated structure including a plurality of layers containing different materials. In this case, the conductive layer 151 may include a layer using a material such as a conductive oxide that can be used for the conductive layer 152, and the conductive layer 152 may include a layer using a material such as a metal material that can be used for the conductive layer 151. For example, when the conductive layer 151 has a laminated structure of two or more layers, the layer in contact with the conductive layer 152 may be a layer using a material that can be used for the conductive layer 152.

[0244] Note that the end of the insulating layer 156 may also have a tapered shape. Specifically, when the end of the insulating layer 156 has a tapered shape with a taper angle less than 90°, the coverage of the structure provided along the side surface of the insulating layer 156 can be improved.

[0245] Figure 5A It is a diagram when the conductive layer 151 has a laminated structure including a plurality of layers containing different materials. As Figure 5AAs shown, the conductive layer 151 includes a conductive layer 151a, a conductive layer 151b on the conductive layer 151a, and a conductive layer 151c on the conductive layer 151b. That is, Figure 5A the shown conductive layer 151 has a three-layer stacked structure. Thus, in the case where the conductive layer 151 has a stacked structure of multiple layers, it is sufficient that the visible light reflectance of at least one of the layers constituting the conductive layer 151 is higher than that of the conductive layer 152.

[0246] In Figure 5A the shown example, the conductive layer 151b is sandwiched by the conductive layer 151a and the conductive layer 151c. The conductive layer 151a and the conductive layer 151c can use materials that are less likely to deteriorate compared to the conductive layer 151b. For example, the conductive layer 151a can use a material that is less likely to undergo migration due to contact with the insulating layer 175 compared to the conductive layer 151b. In addition, the conductive layer 151c can use a material that is less likely to be oxidized compared to the conductive layer 151b; and the resistivity of its oxide is lower than that of the oxide of the material used for the conductive layer 151b.

[0247] Thus, by adopting the structure in which the conductive layer 151b is sandwiched by the conductive layer 151a and the conductive layer 151c, the selection range of the material of the conductive layer 151b can be expanded. Thereby, for example, the conductive layer 151b can be made into a layer whose visible light reflectance is higher than at least one of the conductive layer 151a and the conductive layer 151c. For example, aluminum can be used as the conductive layer 151b. In addition, an aluminum-containing alloy can also be used as the conductive layer 151b. In addition, titanium can be used as the conductive layer 151a. Although the visible light reflectance of titanium is lower than that of aluminum, it is less likely to undergo migration compared to aluminum even when in contact with the insulating layer 175. And, titanium can be used as the conductive layer 151c. Although the visible light reflectance of titanium is lower than that of aluminum, it is less likely to be oxidized compared to aluminum and the resistivity of its oxide is lower than that of aluminum oxide.

[0248] In addition, silver or a silver-containing alloy can also be used as the conductive layer 151c. Silver has the characteristic that its visible light reflectance is higher than that of titanium. Furthermore, silver has the following characteristics: it is less likely to be oxidized compared to aluminum, and the resistivity of silver oxide is lower than that of aluminum oxide. Thus, when silver or a silver-containing alloy is used as the conductive layer 151c, the visible light reflectance of the conductive layer 151 can be appropriately increased while suppressing the increase in the resistance of the pixel electrode due to the oxidation of the conductive layer 151b. Here, as the silver-containing alloy, for example, an alloy of silver, palladium, and copper (Ag-Pd-Cu, also denoted as APC) can be used. In addition, when silver or a silver-containing alloy is used as the conductive layer 151c and aluminum is used as the conductive layer 151b, the visible light reflectance of the conductive layer 151c can be increased compared to the visible light reflectance of the conductive layer 151b. Here, silver or a silver-containing alloy can also be used as the conductive layer 151b. In addition, silver or a silver-containing alloy can also be used as the conductive layer 151a.

[0249] On the other hand, the etch processability of a film using titanium is superior to that of a film using silver. Therefore, by using titanium as the conductive layer 151c, the conductive layer 151c can be easily formed. In addition, the etch processability of a film using aluminum is also superior to that of a film using silver.

[0250] Thus, by making the conductive layer 151 have a stacked structure of multiple layers, the characteristics of the display device can be improved. For example, the display device 100 can be made into a display device with high light extraction efficiency and high reliability.

[0251] Here, when the light-emitting device 130 adopts a microcavity structure, by using silver or a silver-containing alloy, which is a material with high visible light reflectance, as the conductive layer 151c, the light extraction efficiency of the display device 100 can be appropriately increased.

[0252] As described above, the side surface of the conductive layer 151 preferably has a tapered shape. Specifically, the side surface of the conductive layer 151 preferably has a tapered shape with a taper angle less than 90°. For example, in Figure 5A the conductive layer 151 with the structure shown, it is preferable that the side surface of at least one of the conductive layer 151a, the conductive layer 151b, and the conductive layer 151c has a tapered shape.

[0253] Figure 5AThe conductive layer 151 shown can be formed by lithography. Specifically, first, a conductive film that will become the conductive layer 151a, a conductive film that will become the conductive layer 151b, and a conductive film that will become the conductive layer 151c are sequentially deposited. Next, a resist mask is formed on the conductive film that will become the conductive layer 151c. Then, for example, by an etching method, the conductive film in the region that does not overlap with the resist mask is removed. Here, by processing the conductive film under conditions where the resist mask is more likely to retreat (shrink) compared to the case where the conductive layer 151 is formed with a non-tapered shape (i.e., vertical sides), a conductive layer 151 with tapered sides can be formed.

[0254] Here, when processing the conductive film under conditions where the resist mask is likely to retreat (shrink), the conductive film is sometimes likely to be processed in the horizontal direction. In other words, the isotropy of etching is sometimes higher compared to the case where the conductive layer 151 is formed with vertical sides.

[0255] In addition, when the conductive layer 151 has a stacked structure of multiple layers made of different materials, the ease of processing in the horizontal direction of these multiple layers is sometimes different. For example, the ease of processing in the horizontal direction of the conductive layer 151a, the conductive layer 151b, and the conductive layer 151c is sometimes different.

[0256] In this case, sometimes after processing the conductive film, as Figure 5A shown, a protrusion is formed with the side surface of the conductive layer 151b located inside the side surfaces of the conductive layer 151a and the conductive layer 151c. As a result, there is a concern that the coverage of the conductive layer 152 over the conductive layer 151 is reduced and disconnection of the conductive layer 152 occurs.

[0257] In view of this, it is preferable to provide the insulating layer 156 as Figure 5A shown. Figure 5A An example is shown in which the insulating layer 156 is provided on the conductive layer 151a so as to have a region overlapping with the side surface of the conductive layer 151b. Thereby, disconnection or thinning of the conductive layer 152 due to the protrusion can be suppressed, and thus connection failure or an increase in driving voltage can be suppressed.

[0258] Note that although Figure 5A shows a structure in which the entire side surface of the conductive layer 151b is covered with the insulating layer 156, a part of the side surface of the conductive layer 151b may not be covered with the insulating layer 156. The same applies to the pixel electrode having the structure shown below, and a part of the side surface of the conductive layer 151b may not be covered with the insulating layer 156.

[0259] When the conductive layer 151 has Figure 5AWhen in the structure shown, the conductive layer 152 covers the conductive layers 151a, 151b, 151c and the insulating layer 156 and is electrically connected to the conductive layers 151a, 151b and 151c. Thus, for example, when removing the film deposited after forming the conductive layer 152 by a wet etching method, the liquid medicine can also be prevented from contacting the conductive layers 151a, 151b and 151c. Therefore, corrosion occurring in the conductive layers 151a, 151b and 151c can be suppressed. Therefore, the display device 100 can be manufactured by a method with a high yield. In addition, the occurrence of defects can be suppressed, whereby a display device 100 with high reliability can be realized.

[0260] Here, as Figure 5A shown, the insulating layer 156 preferably has a curved surface. Thus, for example, disconnection occurring in the conductive layer 152 covering the insulating layer 156 can be suppressed compared with the case where it is perpendicular to the side surface of the insulating layer 156 (parallel to the Z direction). In addition, when the side surface of the insulating layer 156 has a tapered shape, specifically a tapered shape with a taper angle less than 90°, for example, disconnection occurring in the conductive layer 152 covering the insulating layer 156 can be suppressed compared with the case where it is perpendicular to the side surface of the insulating layer 156. Thus, the display device 100 can be manufactured by a method with a high yield. In addition, the occurrence of defects is suppressed, and the display device 100 can be made into a display device with high reliability.

[0261] Note that Figure 5A a structure is shown in which the side surface of the conductive layer 151b is located inside the side surfaces of the conductive layer 151a and the conductive layer 151c, but one embodiment of the present invention is not limited thereto. For example, the side surface of the conductive layer 151b may also be located outside the side surface of the conductive layer 151a. In addition, the side surface of the conductive layer 151b may also be located outside the side surface of the conductive layer 151c.

[0262] Figures 5B to 5D Another structure of the first electrode 101 is shown. Figure 5B Shown in Figure 5A the first electrode 101 is a structure in which the insulating layer 156 covers the side surfaces of the conductive layers 151a, 151b and 151c in addition to the side surface of the conductive layer 151b.

[0263] Figure 5C Shown in Figure 5A the first electrode 101 is a structure in which the insulating layer 156 is not provided.

[0264] Figure 5D Shown is a structure in which Figure 5A in the first electrode 101, the conductive layer 151 does not have a stacked structure and the conductive layer 152 has a stacked structure.

[0265] The conductive layer 152a is a layer having a closer adhesion to the conductive layer 152b, for example, higher than that of the insulating layer 175. As the conductive layer 152a, for example, an oxide containing one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon can be used. For example, it is preferable to use a conductive oxide containing one or more of indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, zinc oxide containing gallium, titanium oxide, indium titanium oxide, zinc titanate, aluminum zinc oxide, indium zinc oxide containing gallium, indium zinc oxide containing aluminum, indium tin oxide containing silicon, and indium zinc oxide containing silicon. Thereby, film peeling of the conductive layer 152b can be suppressed. In addition, the conductive layer 152b can be made not to contact the insulating layer 175.

[0266] The conductive layer 152b is a layer having a higher visible light reflectance (for example, the reflectance of light at a specified wavelength in the range of 400 nm or more and less than 750 nm) than the conductive layer 151, the conductive layer 152a, and the conductive layer 152c. The visible light reflectance of the conductive layer 152b can be, for example, 70% or more and 100% or less, preferably 80% or more and 100% or less, more preferably 90% or more and 100% or less. In addition, as the conductive layer 152b, for example, a material having a higher visible light reflectance than aluminum can be used. Specifically, for example, silver or a silver-containing alloy can be used as the conductive layer 152b. As the silver-containing alloy, for example, an alloy of silver, palladium, and copper (APC) can be cited. Thereby, the display device 100 can be made a display device with high light extraction efficiency. Note that a metal other than silver can also be used as the conductive layer 152b.

[0267] When the conductive layer 151 and the conductive layer 152 are used as anodes, the conductive layer 152c is preferably a layer having a large work function. The conductive layer 152c is, for example, a layer having a larger work function than the conductive layer 152b. As the conductive layer 152c, for example, the same material as that which can be used for the conductive layer 152a can be used. For example, the same material can be used for the conductive layer 152a and the conductive layer 152c. For example, when indium tin oxide is used for the conductive layer 152a, indium tin oxide can also be used for the conductive layer 152c.

[0268] Note that when the conductive layer 151 and the conductive layer 152 are used as cathodes, the conductive layer 152c is preferably a layer having a small work function. The conductive layer 152c is, for example, a layer having a smaller work function than the conductive layer 152b.

[0269] In addition, the conductive layer 152c is preferably a layer with a high visible light transmittance (for example, the transmittance of light with a specified wavelength in the range of 400 nm or more and less than 750 nm). For example, the visible light transmittance of the conductive layer 152c is preferably higher than that of the conductive layer 151 and the conductive layer 152b. For example, the visible light transmittance of the conductive layer 152c can be 60% or more and 100% or less, preferably 70% or more and 100% or less, and more preferably 80% or more and 100% or less. Thereby, the light emitted from the organic compound layer 103 and absorbed by the conductive layer 152c can be reduced. In addition, as described above, the conductive layer 152b under the conductive layer 152c can be a layer with a high visible light reflectance. Therefore, the display device 100 can be a display device with high light extraction efficiency.

[0270] Next, with reference to Figures 6A to 11C an example of a manufacturing method of the display device 100 having the Figure 4A shown structure will be described. The organic compound layer of the light-emitting device included in the display device 100 is formed through a manufacturing process including water treatment. By using the organic compound of one aspect of the present invention for the organic layer of the light-emitting device included in the display device of one aspect of the present invention, problems such as dissolution of the layer including the organic compound and penetration of the liquid medicine into the layer using the organic compound can be prevented even when manufacturing is performed through a manufacturing method including water treatment, and thus a light-emitting device with good characteristics can be provided.

[0271] [Example of manufacturing method] The thin films (insulating film, semiconductor film, conductive film, etc.) constituting the display device can be formed by a sputtering method, a chemical vapor deposition (CVD: Chemical Vapor Deposition) method, a vacuum evaporation method, a pulsed laser deposition (PLD: Pulsed Laser Deposition) method, or an ALD method, etc. As the CVD method, there are a plasma-enhanced chemical vapor deposition (PECVD: Plasma Enhanced CVD) method and a thermal CVD method, etc. In addition, as one of the thermal CVD methods, there is a metal organic chemical vapor deposition (MOCVD: Metal Organic CVD) method.

[0272] In addition, the thin films (insulating film, semiconductor film, conductive film, etc.) constituting the display device can be formed by wet deposition methods such as a spin coating method, an impregnation method, a spraying method, an inkjet method, a dispenser method, a screen printing method, an offset printing method, a doctor knife method, a slot die coating method, a roll coating method, a curtain coating method, or a blade coating method.

[0273] In particular, when manufacturing a light-emitting device, vacuum processes such as evaporation and solution processes such as spin coating and inkjet printing can be utilized. As evaporation methods, physical vapor deposition (PVD) methods such as sputtering, ion plating, ion beam evaporation, molecular beam epitaxy, and vacuum evaporation, and chemical vapor deposition (CVD) methods can be cited. In particular, methods such as evaporation (such as vacuum evaporation), coating (dip coating, dye coating, bar coating, spin coating, spray coating), printing (inkjet printing, screen printing (stencil printing), offset printing (lithography), flexographic printing (letterpress printing), gravure printing, or microcontact printing, etc.) can be used to form functional layers (hole injection layer, hole transport layer, hole blocking layer, light-emitting layer, electron blocking layer, electron transport layer, electron injection layer, etc.) included in the organic compound layer.

[0274] In addition, when processing a thin film constituting a display device, for example, photolithography can be used for processing. Alternatively, the thin film can be processed by nanoimprinting, sandblasting, peeling, etc. In addition, island-shaped thin films can be directly formed by a deposition method using a masking mask such as a metal mask.

[0275] As photolithography, for example, lithography can be used. Typically, there are the following two methods of lithography. One is a method of forming a resist mask on a thin film to be processed, processing the thin film by etching, for example, and removing the resist mask. The other is a method of forming a photosensitive thin film and then performing exposure and development to process the thin film into a desired shape.

[0276] In lithography, as the light for exposure, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or light obtained by mixing these lights can be used. In addition, ultraviolet light, KrF laser, ArF laser, etc. can also be used. In addition, immersion exposure technology can be used for exposure. In addition, as the light for exposure, extreme ultraviolet (EUV) light or X-rays can also be used. In addition, instead of the light for exposure, an electron beam can be used. When using extreme ultraviolet light, X-rays, or an electron beam, extremely fine processing can be performed, so it is preferred. In addition, when exposure is performed by scanning a light beam such as an electron beam, a photomask is not required.

[0277] In the etching of a thin film, dry etching, wet etching, sandblasting, etc. can be utilized.

[0278] First, as Figure 6AAn insulating layer 171 is formed on a substrate (not shown). Next, a conductive layer 172 and a conductive layer 179 are formed on the insulating layer 171, and an insulating layer 173 is formed on the insulating layer 171 so as to cover the conductive layer 172 and the conductive layer 179. Next, an insulating layer 174 is formed on the insulating layer 173, and an insulating layer 175 is formed on the insulating layer 174.

[0279] As the substrate, a substrate having at least heat resistance capable of withstanding the subsequent heat treatment can be used. In the case of using an insulating substrate as the substrate, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, an organic resin substrate, or the like can be used. In addition, a single crystal semiconductor substrate or a polycrystalline semiconductor substrate made of silicon or silicon carbide, a compound semiconductor substrate made of silicon germanium, an SOI substrate, or the like can also be used as the semiconductor substrate.

[0280] Next, as Figure 6A shown, an opening reaching the conductive layer 172 is formed in the insulating layer 175, the insulating layer 174, and the insulating layer 173. Next, a plug 176 is formed so as to fill the opening.

[0281] Next, as Figure 6A shown, a conductive film 151f that will later become the conductive layer 151R, the conductive layer 151G, the conductive layer 151B, and the conductive layer 151C is formed on the plug 176 and the insulating layer 175. The conductive film 151f can be formed, for example, by a sputtering method or a vacuum evaporation method. In addition, a metal material can be used as the conductive film 151f, for example.

[0282] Next, as Figure 6A shown, a conductive film 152f that will later become the conductive layer 152R, the conductive layer 152G, the conductive layer 152B, and the conductive layer 152C is formed on the conductive film 151f. The conductive film 152f can be formed, for example, by a sputtering method or a vacuum evaporation method. In addition, a conductive oxide can be used as the conductive film 152f, for example. Alternatively, a laminated structure of a film using a metal material and a film using a conductive oxide on the film can be adopted as the conductive film 152f. For example, a laminated structure of a film using titanium, silver, or a silver-containing alloy and a film using a conductive oxide on the film can be adopted as the conductive film 152f.

[0283] In addition, the conductive film 152f can be formed by ALD method. Here, as the conductive film 152f, an oxide containing one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon can be used. At this time, by repeating the cycle with the introduction of a precursor (which is generally sometimes referred to as a precursor or metal precursor, etc.), the purge of this precursor, the introduction of an oxidant (which is generally sometimes referred to as a reactant, reactant, or non-metal precursor, etc.), and the purge of this oxidant as one cycle, the conductive film 152f can be formed. Here, when forming an oxide film containing multiple metals such as indium tin oxide as the conductive film 152f, the metal composition can be controlled by changing the number of cycles according to the type of precursor.

[0284] For example, in the case of depositing an indium tin oxide film as the conductive film 152f, after introducing a precursor containing indium, this precursor is purged and an oxidant is introduced to form an In-O film. Next, after introducing a precursor containing tin, this precursor is purged and an oxidant is introduced to form an Sn-O film. Here, by making the number of cycles when forming the In-O film more than the number of cycles when forming the Sn-O film, the number of In atoms contained in the conductive film 152f can be made more than the number of Sn atoms.

[0285] In addition, for example, in the case of depositing a zinc oxide film as the conductive film 152f, a Zn-O film is formed by the above process. In addition, for example, in the case of depositing an aluminum zinc oxide film as the conductive film 152f, a Zn-O film and an Al-O film are formed by the above process. In addition, for example, in the case of depositing a titanium oxide film as the conductive film 152f, a Ti-O film is formed by the above process. In addition, for example, in the case of depositing an indium tin oxide film containing silicon as the conductive film 152f, an In-O film, an Sn-O film, and an Si-O film are formed by the above process. In addition, for example, in the case of depositing a zinc oxide film containing gallium, a Ga-O film and a Zn-O film are formed by the above process.

[0286] As a precursor containing indium, for example, triethylindium, trimethylindium, or [1,1,1-trimethyl-N-(trimethylsilyl)amide]-indium can be used. As a precursor containing tin, for example, tin chloride or tin bis(dimethylamide) can be used. As a precursor containing zinc, for example, diethylzinc or dimethylzinc can be used. As a precursor containing gallium, for example, triethylgallium can be used. As a precursor containing titanium, for example, titanium chloride, titanium bis(dimethylamide), or tetraisopropyl titanate can be used. As a precursor containing aluminum, for example, aluminum chloride or trimethylaluminum can be used. As a precursor containing silicon, for example, trisilylamine, bis(diethylamino)silane, tris(dimethylamino)silane, bis(tert-butylamino)silane, or bis(ethylmethylamino)silane can be used. In addition, as the oxidant, water vapor, oxygen plasma, or ozone gas can be used.

[0287] Next, as Figure 6A shown, a resist mask 191 is formed on the conductive film 151f and the conductive film 152f. The resist mask 191 can be formed by coating a photosensitive material (photoresist) and then performing exposure and development.

[0288] Next, as Figure 6B shown, for example, by using an etching method, specifically a dry etching method, the conductive film 151f and the conductive film 152f in the regions not overlapping with the resist mask 191 are removed, thereby forming pixel electrodes including the conductive layer 151 and the conductive layer 152. Note that, in the case where the conductive film 151f includes a layer using a conductive oxide such as indium tin oxide, the layer can also be removed by a wet etching method. Thus, the conductive layer 151 and the conductive layer 152 are formed. Note that, for example, when a part of the conductive film 151f is removed by a dry etching method, recesses may be formed in the region of the insulating layer 175 that does not overlap with the conductive layer 151.

[0289] Note that, after forming the conductive layer 152R, the conductive layer 152G, the conductive layer 152B, and the conductive layer 152C by processing the conductive film 152f using lithography technology, the conductive film 151f can be processed using the conductive layer 152R, the conductive layer 152G, the conductive layer 152B, and the conductive layer 152C as masks. Specifically, for example, after forming the resist mask, a part of the conductive film 152f is removed by an etching method. The conductive film 152f can be removed, for example, by a wet etching method. Note that the conductive film 152f can also be removed by a dry etching method. Then, it is preferable to remove the conductive film 151f by a wet etching method.

[0290] Here, it is preferable to perform a hydrophobization treatment on the conductive layer 152. By the hydrophobization treatment, the surface state of the object to be treated can be changed from hydrophilic to hydrophobic, or the hydrophobicity of the surface of the object to be treated can be increased. By performing the hydrophobization treatment on the conductive layer 152, the adhesion between the conductive layer 152 and the organic compound layer 103 to be formed in a later process can be improved to suppress film peeling. Note that the hydrophobization treatment may not be performed.

[0291] Next, as Figure 6C shown, the resist mask 191 is removed. The resist mask 191 can be removed, for example, by ashing using oxygen plasma. Or, oxygen gas and CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, or a Group 18 element such as He can also be used. Or, the resist mask 191 can be removed by wet etching.

[0292] Next, next, as Figure 6DAs shown, an insulating film 156f that will later become insulating layers 156R, 156G, 156B, and 156C is formed on conductive layers 151R and 152R, conductive layers 151G and 152G, conductive layers 151B and 152B, conductive layers 151C and 152C, and insulating layer 175. The insulating film 156f can be formed, for example, by CVD method, ALD method, sputtering method, or vacuum evaporation method.

[0293] The insulating film 156f can use inorganic materials. As the insulating film 156f, for example, inorganic insulating films such as oxide insulating film, nitride insulating film, oxynitride insulating film, or nitrogen oxide insulating film can be used. For example, as the insulating film 156f, an oxide insulating film, nitride insulating film, oxynitride insulating film, or nitrogen oxide insulating film containing silicon can be used. For example, silicon oxynitride can be used as the insulating film 156f.

[0294] Next, as Figure 6E shown, the insulating film 156f is processed to form insulating layers 156R, 156G, 156B, and 156C. For example, by etching the top surface of the insulating film 156f approximately uniformly, the insulating layer 156 can be formed. The process of etching uniformly like this for planarization is also called etch-back process. In addition, the insulating layer 156 can also be formed using lithography technology.

[0295] Next, as Figure 7A shown, an organic compound film 103Rf that will later become an organic compound layer 103R is formed on conductive layers 152R, 152G, 152B, insulating layers 156R, 156G, 156B, and insulating layer 175.

[0296] As Figure 7A shown, the organic compound film 103Rf is not formed on the conductive layer 152C. For example, by using a mask for defining the deposition range (also called a region mask or a coarse metal mask, etc. to distinguish from a high-precision metal mask), the organic compound film 103Rf can be deposited only in the desired region. By adopting a deposition process using a region mask and a processing process using a resist mask, a light-emitting device can be manufactured with a relatively simple process.

[0297] The organic compound film 103Rf can be formed, for example, by evaporation method, specifically by vacuum evaporation method. In addition, the organic compound film 103Rf can also be formed by methods such as transfer method, printing method, inkjet method, or coating method.

[0298] Next, as Figure 7AAs shown, a sacrificial film 158Rf that will later become a sacrificial layer 158R and a mask film 159Rf that will later become a mask layer 159R are sequentially formed on the organic compound film 103Rf, the conductive layer 152C, and the insulating layer 175.

[0299] Note that, in the present embodiment, an example is shown in which the mask film is composed of a two-layer structure of the sacrificial film 158Rf and the mask film 159Rf, but the mask film may have a single-layer structure or a laminated structure of three or more layers.

[0300] By providing a sacrificial layer on the organic compound film 103Rf, damage to the organic compound film 103Rf during the manufacturing process of the display device can be reduced, and the reliability of the light-emitting device can be improved.

[0301] As the sacrificial film 158Rf, a film with high resistance to the processing conditions of the organic compound film 103Rf is used. Specifically, a film with a large etching selectivity ratio with respect to the organic compound film 103Rf is used. As the mask film 159Rf, a film with a large etching selectivity ratio with respect to the sacrificial film 158Rf is used.

[0302] In addition, the sacrificial film 158Rf and the mask film 159Rf are formed at a temperature lower than the heat-resistant temperature of the organic compound film 103Rf. The substrate temperature when forming the sacrificial film 158Rf and the sacrificial film 159Rf is typically 200°C or lower, preferably 150°C or lower, more preferably 120°C or lower, further preferably 100°C or lower, and still more preferably 80°C or lower.

[0303] As the sacrificial film 158Rf and the mask film 159Rf, a film that can be removed by a wet etching method is preferably used. By using the wet etching method, damage to the organic compound film 103Rf during the processing of the sacrificial film 158Rf and the mask film 159Rf can be reduced compared to the case of using a dry etching method.

[0304] The sacrificial film 158Rf and the mask film 159Rf can be formed, for example, by a sputtering method, an ALD method (thermal ALD method, PEALD method), a CVD method, or a vacuum evaporation method. In addition, they can also be formed by the above-mentioned wet deposition methods.

[0305] The sacrificial film 158Rf formed in contact with the organic compound film 103Rf is preferably formed by a forming method that causes less damage to the organic compound film 103Rf compared to when forming the mask film 159Rf. For example, compared to the sputtering method, it is more preferable to use the ALD method or the vacuum evaporation method to form the sacrificial film 158Rf.

[0306] As the sacrificial film 158Rf and the mask film 159Rf, one or more of a metal film, an alloy film, a metal oxide film, a semiconductor film, an organic insulating film, an inorganic insulating film, etc. can be used, for example.

[0307] As the sacrificial film 158Rf and the mask film 159Rf, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, and tantalum, or alloy materials containing such metal materials can be used respectively, for example. Low melting point materials such as aluminum or silver are particularly preferably used. By using a metal material capable of shielding ultraviolet rays as one or both of the sacrificial film 158Rf and the mask film 159Rf, the irradiation of ultraviolet rays to the organic compound film 103Rf can be suppressed, and the deterioration of the organic compound film 103Rf can be suppressed, so it is preferable.

[0308] In addition, as the sacrificial film 158Rf and the mask film 159Rf, metal oxides such as In-Ga-Zn oxide, indium oxide, In-Zn oxide, In-Sn oxide, indium titanium oxide (In-Ti oxide), indium tin zinc oxide (In-Sn-Zn oxide), indium titanium zinc oxide (In-Ti-Zn oxide), indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide), or indium tin oxide containing silicon, etc. can be used respectively.

[0309] Note that the above gallium can also be replaced by an element M (M is one or more of aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium).

[0310] In addition, as the sacrificial film and the mask film, a film containing a material having light-shielding properties, particularly ultraviolet light-shielding properties, is preferably used. As the light-shielding material, various materials such as a metal, an insulator, a semiconductor, and a semimetal having ultraviolet light-shielding properties can be used. Since a part or all of the sacrificial film and the mask film will be removed in a later process, the sacrificial film and the mask film are preferably films that can be processed by etching, and particularly preferably films with good processability.

[0311] When a semiconductor material such as silicon or germanium is used as the sacrificial film and the mask film, for example, the affinity of this material for the semiconductor manufacturing process is high, so it is preferable. Alternatively, an oxide or nitride of the above semiconductor material can be used. Alternatively, a non-metallic material such as carbon or its compound can be used. In addition, a metal such as titanium, tantalum, tungsten, chromium, aluminum, or an alloy containing one or more of them can be used. In addition, an oxide containing the above metal such as titanium oxide or chromium oxide, or a nitride such as titanium nitride, chromium nitride, or tantalum nitride can be used.

[0312] In addition, by using a film made of a material having ultraviolet light-shielding properties as a sacrificial film or a mask film, it is possible to suppress, for example, ultraviolet light from irradiating the organic compound layer in the exposure process. By suppressing damage to the organic compound layer caused by ultraviolet light, the reliability of the light-emitting device can be improved.

[0313] Note that the same effect is also produced when a film containing a material having ultraviolet light-shielding properties is used as the material for the inorganic insulating film 125f described later.

[0314] In addition, various inorganic insulating films can be used as the sacrificial film 158Rf and the mask film 159Rf, respectively. In particular, an oxide insulating film has a higher adhesion to the organic compound film 103Rf than a nitride insulating film, so it is preferred. For example, inorganic insulating materials such as alumina, hafnium oxide, or silicon oxide can be used for the sacrificial film 158Rf and the mask film 159Rf. As the sacrificial film 158Rf and the mask film 159Rf, an alumina film can be formed by ALD method, for example. By using the ALD method, damage to the substrate (especially to the organic compound layer) can be reduced, so it is preferred.

[0315] For example, an inorganic insulating film (e.g., an alumina film) formed by ALD method can be used as the sacrificial film 158Rf, and an inorganic film (e.g., an In-Ga-Zn oxide film, an aluminum film, or a tungsten film) formed by sputtering method can be used as the mask film 159Rf.

[0316] In addition, the same inorganic insulating film can be used for both the sacrificial layer 158Rf and the inorganic insulating layer 125 to be formed later. For example, an alumina film formed by ALD method can be used for both the sacrificial layer 158Rf and the inorganic insulating layer 125. Here, the sacrificial layer 158Rf and the inorganic insulating layer 125 can be deposited under the same deposition conditions or different deposition conditions. For example, by depositing the sacrificial film 158Rf under the same conditions as the inorganic insulating layer 125, an insulating layer with high barrier properties against at least one of water and oxygen can be formed as the sacrificial film 158Rf. On the other hand, since most or all of the sacrificial film 158Rf will be removed in a later process, it is preferably easy to process. Therefore, the sacrificial layer 158Rf is preferably deposited under conditions with a lower substrate temperature than the inorganic insulating layer 125 during deposition.

[0317] As one or both of the sacrificial film 158Rf and the mask film 159Rf, an organic material may also be used. For example, as the organic material, a material that can be dissolved in a solvent that is at least chemically stable to the film located at the uppermost part of the organic compound film 103Rf may be used. In particular, a material that can be dissolved in water or alcohol can be appropriately used. When depositing the above material, preferably, the material is applied by a wet deposition method in a state where the material is dissolved in a solvent such as water or alcohol, and then a heat treatment for evaporating the solvent is performed. At this time, it is preferable to perform the heat treatment in a reduced-pressure atmosphere, whereby the solvent can be removed at a low temperature and in a short time, and the thermal damage to the organic compound film 103Rf can be reduced.

[0318] As the sacrificial film 158Rf and the mask film 159Rf, organic resins such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerol, pullulan, water-soluble cellulose, a polyamide resin soluble in alcohol, or a fluororesin such as a perfluoropolymer may also be used.

[0319] For example, as the sacrificial film 158Rf, an organic film (e.g., a PVA film) formed by any one of vapor deposition and the above wet deposition method may be used, and as the mask film 159Rf, an inorganic film (e.g., a silicon nitride film) formed by sputtering may be used.

[0320] Next, as Figure 7A shown, a resist mask 190R is formed on the mask film 159Rf. The resist mask 190R can be formed by applying a photosensitive material (photoresist) and performing exposure and development.

[0321] The resist mask 190R can use a positive resist material or a negative resist material.

[0322] The resist mask 190R is provided at a position overlapping the conductive layer 152R. The resist mask 190R is preferably also provided at a position overlapping the conductive layer 152C. Thereby, damage to the conductive layer 152C during the manufacturing process of the display device can be suppressed. Note that the resist mask 190R may not be provided on the conductive layer 152C. In addition, as shown in the cross-sectional view along B1 - B2 in Figure 7A , the resist mask 190R is preferably provided so as to cover the end of the organic compound film 103Rf to the end of the conductive layer 152C (the end on the organic compound film 103Rf side).

[0323] Next, as Figure 7BAs shown, a part of the mask film 159Rf is removed using a resist mask 190R to form a mask layer 159R. The mask layer 159R remains on the conductive layer 152R and the conductive layer 152C. Then, the resist mask 190R is removed. Next, the mask layer 159R is used as a mask (also referred to as a hard mask) to remove a part of the sacrificial film 158Rf to form a sacrificial layer 158R.

[0324] The sacrificial film 158Rf and the mask film 159Rf can be processed by a wet etching method or a dry etching method, respectively. The processing of the sacrificial film 158Rf and the mask film 159Rf is preferably performed by isotropic etching.

[0325] By using the wet etching method, compared with the case of using the dry etching method, the damage to the organic compound film 103Rf during the processing of the sacrificial film 158Rf and the mask film 159Rf can be reduced. When using the wet etching method, for example, it is preferable to use a developing solution, an aqueous solution of tetramethylammonium hydroxide (TMAH), dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or a liquid medicine such as a mixed liquid thereof.

[0326] When processing the mask film 159Rf, the organic compound film 103Rf is not exposed, so the range of choices for the processing method is wider compared with the case of processing the sacrificial film 158Rf. Specifically, when processing the mask film 159Rf, even if an oxygen-containing gas is used as the etching gas, the deterioration of the organic compound film 103Rf can be suppressed.

[0327] In addition, when using the dry etching method for the processing of the sacrificial film 158Rf, the deterioration of the organic compound film 103Rf can be suppressed by not using an oxygen-containing gas as the etching gas. In the case of using the dry etching method, for example, it is preferable to use a gas containing CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, or a Group 18 element such as He as the etching gas.

[0328] For example, when using an aluminum oxide film formed by the ALD method as the sacrificial film 158Rf, a part of the sacrificial film 158Rf can be removed by dry etching using CHF3 and He or CHF3, He, and CH4. In addition, when using an In-Ga-Zn oxide film formed by sputtering as the mask film 159Rf, a part of the mask film 159Rf can be removed by wet etching using dilute phosphoric acid. Or, a part of the mask film 159Rf can be removed by dry etching using CH4 and Ar. Or, a part of the mask film 159Rf can be removed by wet etching using dilute phosphoric acid. In addition, in the case of using a tungsten film formed by sputtering as the mask film 159Rf, a part of the mask film 159Rf can be removed by dry etching using SF6, CF4, and O2 or CF4, Cl2, and O2.

[0329] The resist mask 190R can be removed by the same method as the resist mask 191. The resist mask 190R can be removed, for example, by ashing using oxygen plasma. Alternatively, oxygen gas and CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, or a Group 18 element such as He can also be used. Alternatively, the resist mask 190R can be removed by wet etching. At this time, since the sacrificial film 158Rf is located on the outermost surface and the organic compound film 103Rf is not exposed, damage to the organic compound film 103Rf can be suppressed in the process of removing the resist mask 190R. In addition, the selection range of the method for removing the resist mask 190R can be expanded.

[0330] Next, as Figure 7B shown, the organic compound film 103Rf is processed to form an organic compound layer 103R. For example, the mask layer 159R and the sacrificial layer 158R are used as hard masks to remove a part of the organic compound film 103Rf to form the organic compound layer 103R.

[0331] Thus, as Figure 7B shown, a stacked structure of the organic compound layer 103R, the sacrificial layer 158R, and the mask layer 159R remains on the conductive layer 152R. In addition, the conductive layer 152G and the conductive layer 152B are exposed.

[0332] Figure 7B An example is shown in which the end of the organic compound layer 103R is located outside the end of the conductive layer 152R. By adopting this structure, miniaturization of the pixel can be achieved, and a high-definition display can be manufactured. Note that although not shown in Figure 7B , recesses may sometimes be formed in the region of the insulating layer 175 that does not overlap with the organic compound layer 103R due to the above-described etching process.

[0333] As described above, the resist mask 190R is preferably provided so as to cover the end of the organic compound layer 103R to the end of the conductive layer 152C (the end on the organic compound layer 103R side) between B1 - B2. Thus, as Figure 7B shown, the sacrificial layer 158R and the mask layer 159R are provided so as to cover the end of the organic compound layer 103R to the end of the conductive layer 152C (the end on the organic compound layer 103R side) between the dotted lines B1 - B2. Therefore, exposure of the insulating layer 175, for example, between B1 - B2 can be suppressed. As a result, it is possible to suppress removal of a part of the insulating layer 175, the insulating layer 174, and the insulating layer 173 by etching or the like, resulting in exposure of the conductive layer 179. Therefore, unintentional electrical connection of the conductive layer 179 to other conductive layers can be suppressed. For example, a short circuit between the conductive layer 179 and the common electrode 155 to be formed in a later process can be suppressed.

[0334] Preferably, the organic compound film 103Rf is processed by anisotropic etching. More preferably, anisotropic dry etching is used. Alternatively, wet etching may also be used.

[0335] When using the dry etching method, the deterioration of the organic compound film 103Rf can be suppressed by not using an oxygen-containing gas as the etching gas.

[0336] In addition, an oxygen-containing gas may also be used as the etching gas. When the etching gas contains oxygen, the etching rate can be increased. Therefore, etching can be performed under low-power conditions while maintaining a sufficient etching rate. Therefore, damage to the organic compound film 103Rf can be suppressed. Also, defects such as the adhesion of reaction products generated during etching can be suppressed.

[0337] When using the dry etching method, for example, it is preferable to use a gas containing one or more of H2, CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, and a Group 18 element such as He or Ar as the etching gas. Alternatively, it is preferable to use a gas containing one or more of the above gases and oxygen as the etching gas. Alternatively, oxygen gas may also be used as the etching gas. Specifically, for example, a gas containing H2 and Ar or a gas containing CF4 and He can be used as the etching gas. In addition, for example, a gas containing CF4, He, and oxygen can be used as the etching gas. Further, for example, a gas containing H2 and Ar and an oxygen-containing gas can be used as the etching gas.

[0338] As described above, in one aspect of the present invention, a mask layer 159R is formed by forming a resist mask 190R on the mask film 159Rf and removing a part of the mask film 159Rf using the resist mask 190R. Then, an organic compound layer 103R is formed by using the mask layer 159R as a mask to remove a part of the organic compound film 103Rf. Therefore, it can be said that the organic compound layer 103R is formed by processing the organic compound film 103Rf using lithography. In addition, a part of the organic compound film 103Rf may be removed using the resist mask 190R. Then, the resist mask 190R may also be removed.

[0339] Next, for example, it is preferable to perform a hydrophobization treatment on the conductive layer 152G. When processing the organic compound film 103Rf, for example, the surface state of the conductive layer 152G sometimes becomes hydrophilic. By performing the hydrophobization treatment on the conductive layer 152G, for example, the adhesion between the conductive layer 152G and the layer (here, the organic compound layer 103G) to be formed in a later process can be improved to suppress film peeling. Note that the hydrophobization treatment may not be performed.

[0340] Next, as Figure 8AAs shown, an organic compound film 103Gf which will later become the organic compound layer 103G is formed on the conductive layer 152G, the conductive layer 152B, the insulating layer 156R, the insulating layer 156G, the insulating layer 156B, the mask layer 159R, and the insulating layer 175.

[0341] The organic compound film 103Gf can be formed by the same method as that which can be used when forming the organic compound film 103Rf. Additionally, the organic compound film 103Gf can have the same structure as the organic compound film 103Rf.

[0342] Next, as Figure 8A shown, a sacrificial film 158Gf which will later become the sacrificial layer 158G and a mask film 159Gf which will later become the mask layer 159G are sequentially formed on the organic compound film 103Gf and the mask layer 159R. Then, a resist mask 190G is formed. The materials and formation methods of the sacrificial film 158Gf and the mask film 159Gf are the same as the conditions that can be used for the sacrificial film 158Rf and the mask film 159Rf. The materials and formation methods of the resist mask 190G are the same as the conditions that can be applied to the resist mask 190R.

[0343] The resist mask 190G is provided at a position overlapping with the conductive layer 152G.

[0344] Next, as Figure 8B shown, a part of the mask film 159Gf is removed using the resist mask 190G to form the mask layer 159G. The mask layer 159G remains on the conductive layer 152G. Then, the resist mask 190G is removed. Next, a part of the sacrificial film 158Gf is removed using the mask layer 159G as a mask to form the sacrificial layer 158G. Next, the organic compound film 103Gf is processed to form the organic compound layer 103G. For example, a part of the organic compound film 103Gf is removed using the mask layer 159G and the sacrificial layer 158G as a hard mask to form the organic compound layer 103G.

[0345] Thus, as Figure 8B shown, a stacked structure of the organic compound layer 103G, the sacrificial layer 158G, and the mask layer 159G remains on the conductive layer 152G. In addition, the mask layer 159R and the conductive layer 152B are exposed.

[0346] Next, for example, it is preferable to perform a hydrophobization treatment on the conductive layer 152B. When processing the organic compound film 103Gf, for example, the surface state of the conductive layer 152B sometimes becomes hydrophilic. By performing the hydrophobization treatment on the conductive layer 152B, for example, the adhesion between the conductive layer 152B and the layer to be formed in a later process (here, the organic compound layer 103B) can be improved to suppress film peeling. Note that the hydrophobization treatment may not be performed.

[0347] Next, as Figure 8C shown, an organic compound film 103Bf that will later become the organic compound layer 103B is formed on the conductive layer 152B, the mask layer 159R, the insulating layer 156R, the insulating layer 156G, the insulating layer 156B, the mask layer 159G, and the insulating layer 175.

[0348] The organic compound film 103Bf can be formed in the same manner as the method that can be used when forming the organic compound film 103Rf. Additionally, the organic compound film 103Bf can have the same structure as the organic compound film 103Rf.

[0349] Next, as Figure 8C shown, a sacrificial film 158Bf that will later become the sacrificial layer 158B and a mask film 159Bf that will later become the mask layer 159B are sequentially formed on the organic compound film 103Bf and the mask layer 159R. Then, a resist mask 190B is formed. The materials and formation methods of the sacrificial film 158Bf and the mask film 159Bf are the same as the conditions that can be used for the sacrificial film 158Rf and the mask film 159Rf. The materials and formation methods of the resist mask 190B are the same as the conditions that can be applied to the resist mask 190R.

[0350] The resist mask 190B is provided at a position overlapping with the conductive layer 152B.

[0351] Next, as Figure 8D shown, a part of the mask film 159Bf is removed using the resist mask 190B to form the mask layer 159B. The mask layer 159B remains on the conductive layer 152B. Then, the resist mask 190B is removed. Next, a part of the sacrificial film 158Bf is removed using the mask layer 159B as a mask to form the sacrificial layer 158B. Next, the organic compound film 103Bf is processed to form the organic compound layer 103B. For example, a part of the organic compound film 103Bf is removed using the mask layer 159B and the sacrificial layer 158B as a hard mask to form the organic compound layer 103B.

[0352] Thus, as Figure 8D shown, a stacked structure of the organic compound layer 103B, the sacrificial layer 158B, and the mask layer 159B remains on the conductive layer 152B. In addition, the mask layer 159R and the mask layer 159G are exposed.

[0353] Note that the sides of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B are each preferably perpendicular or substantially perpendicular to the formation surface. For example, the angle formed by the formation surface and these sides is preferably 60 degrees or more and 90 degrees or less.

[0354] As described above, the distance between two adjacent organic compound layers among the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B formed using lithography technology can be reduced to 8 μm or less, 5 μm or less, 3 μm or less, 2 μm or less, or 1 μm or less. Here, for example, this distance can be defined based on the distance between the opposing ends of two adjacent organic compound layers among the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B. In this way, by reducing the distance between the island-shaped organic compound layers, a display device with high clarity and a large aperture ratio can be provided. In addition, the distance between the first electrodes of adjacent light-emitting devices can also be reduced, for example, to 10 μm or less, 8 μm or less, 5 μm or less, 3 μm or less, 2 μm or less. In addition, the distance between the first electrodes of adjacent light-emitting devices is preferably 2 μm or more and 5 μm or less.

[0355] Next, as Figure 9A shown, it is preferable to remove the mask layer 159R, the mask layer 159G, and the mask layer 159B. Depending on subsequent processes, the sacrificial layer 158R, the sacrificial layer 158G, the sacrificial layer 158B, the mask layer 159R, the mask layer 159G, and the mask layer 159B may remain in the display device. By removing the mask layer 159R, the mask layer 159G, and the mask layer 159B at this stage, it is possible to prevent the mask layer 159R, the mask layer 159G, and the mask layer 159B from remaining in the display device. For example, when a conductive material is used for the mask layer 159R, the mask layer 159G, and the mask layer 159B, by removing the mask layer 159R, the mask layer 159G, and the mask layer 159B in advance, it is possible to suppress the generation of leakage current and the formation of capacitance due to the remaining mask layer 159R, the mask layer 159G, and the mask layer 159B.

[0356] Note that although the case of removing the mask layer 159R, the mask layer 159G, and the mask layer 159B is described as an example in this embodiment, it is also possible not to remove the mask layer 159R, the mask layer 159G, and the mask layer 159B. For example, when the mask layer 159R, the mask layer 159G, and the mask layer 159B contain the above-mentioned material having ultraviolet light-shielding properties, it is preferable to enter the next process without removing the above mask layer in order to protect the organic compound layer from ultraviolet light.

[0357] As the process for removing the mask layer, the same method as the process for processing the mask film can be used. By using the wet etching method, compared with the case of using the dry etching method, the damage to the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B during the removal of the mask layer can be reduced.

[0358] Alternatively, the mask layer can also be removed by dissolving it in a solvent such as water or alcohol. Examples of the alcohol include ethanol, methanol, isopropyl alcohol (IPA), or glycerol.

[0359] After removing the mask layer, a drying process can also be performed to remove the water contained in the organic compound layers 103R, 103G, and 103B and the water adsorbed on the surfaces of the organic compound layers 103R, 103G, and 103B. For example, a heat treatment can be performed in an inert gas atmosphere or a reduced pressure atmosphere. The heat treatment can be performed at a substrate temperature of 50°C or higher and 200°C or lower, preferably 60°C or higher and 150°C or lower, and more preferably 70°C or higher and 120°C or lower. By using a reduced pressure atmosphere, drying can be performed at a lower temperature, so it is preferred.

[0360] Next, as Figure 9B shown, an inorganic insulating film 125f that will later become the inorganic insulating layer 125 is formed so as to cover the organic compound layers 103R, 103G, 103B, the sacrificial layers 158R, 158G, and 158B.

[0361] As described later, an insulating film that will later become the insulating layer 127 is formed in contact with the top surface of the inorganic insulating film 125f. Therefore, the top surface of the inorganic insulating film 125f preferably has high affinity with the material for this insulating film (for example, a photosensitive resin composition containing an acrylic resin). To improve this affinity, surface treatment can also be performed to hydrophobize (or increase its hydrophobicity) the top surface of the inorganic insulating film 125f. For example, it is preferred to perform treatment using a silylating agent such as hexamethyldisilazane (HMDS). By hydrophobizing the top surface of the inorganic insulating film 125f in this way, the insulating film 127f can be formed with high adhesion. In addition, as the surface treatment, the above-mentioned hydrophobization treatment can also be performed.

[0362] Next, as Figure 9C shown, an insulating film 127f that will later become the insulating layer 127 is formed on the inorganic insulating film 125f.

[0363] The inorganic insulating film 125f and the insulating film 127f are preferably deposited by a formation method that causes less damage to the organic compound layers 103R, 103G, and 103B. In particular, since the inorganic insulating film 125f is formed in contact with the side surfaces of the organic compound layers 103R, 103G, and 103B, the inorganic insulating film 125f is preferably deposited by a formation method that causes less damage to the organic compound layers 103R, 103G, and 103B than when depositing the insulating film 127f.

[0364] In addition, the inorganic insulating film 125f and the insulating film 127f are each formed at a temperature lower than the heat-resistant temperature of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B. By increasing the substrate temperature during deposition, an inorganic insulating film 125f with a low impurity concentration and high barrier properties against at least one of water and oxygen can be formed even if its thickness is thin.

[0365] The substrate temperature when forming the inorganic insulating film 125f and the insulating film 127f is preferably 60 °C or higher, 80 °C or higher, 100 °C or higher, or 120 °C or higher and 200 °C or lower, 180 °C or lower, 160 °C or lower, 150 °C or lower, or 140 °C or lower.

[0366] As the inorganic insulating film 125f, it is preferable to form an insulating film with a thickness of 3 nm or more, 5 nm or more, or 10 nm or more and 200 nm or less, 150 nm or less, 100 nm or less, or 50 nm or less within the above substrate temperature range.

[0367] The inorganic insulating film 125f is preferably formed by, for example, the ALD method. By using the ALD method, deposition damage can be reduced, and a film with high coverage can be deposited, so it is preferable. As the inorganic insulating film 125f, for example, it is preferable to form an aluminum oxide film by the ALD method.

[0368] In addition to this, the inorganic insulating film 125f can also be formed by a sputtering method, a CVD method, or a PECVD method with a deposition rate higher than that of the ALD method. Thereby, a display device with high reliability can be manufactured with high productivity.

[0369] The insulating film 127f is preferably formed by the above wet deposition method. The insulating film 127f is preferably formed by spin coating using a photosensitive material, and more specifically, it is preferably formed using a photosensitive resin composition containing an acrylic resin.

[0370] For example, it is preferable to form the insulating film 127f using a resin composition containing a polymer, an acid generator, and a solvent. The polymer is formed using one or more monomers and has a structure in which one or more structural units (also referred to as constituent units) are repeated regularly or irregularly. As the acid generator, one or both of a compound that generates an acid by irradiating light and a compound that generates an acid by heating can be used. The resin composition may further contain one or more of a photosensitizer, a sensitizer, a catalyst, an adhesion aid, a surfactant, and an antioxidant.

[0371] In addition, it is preferable to perform a heat treatment (also referred to as pre-baking) after forming the insulating film 127f. This heat treatment is performed at a temperature lower than the heat-resistant temperature of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B. The substrate temperature during the heat treatment is preferably 50°C or higher and 200°C or lower, more preferably 60°C or higher and 150°C or lower, and still more preferably 70°C or higher and 120°C or lower. Thereby, the solvent in the insulating film 127f can be removed.

[0372] Next, exposure is performed to expose a part of the insulating film 127f with visible light or ultraviolet light. Here, when a positive photosensitive resin composition containing an acrylic resin is used for the insulating film 127f, visible light or ultraviolet light is irradiated to the region where the insulating layer 127 will not be formed in the subsequent process. The insulating layer 127 is formed in the region sandwiched by any two of the conductive layers 152R, the conductive layer 152G, and the conductive layer 152B and around the conductive layer 152C. Therefore, visible light or ultraviolet light is irradiated to the conductive layers 152R, the conductive layer 152G, the conductive layer 152B, and the conductive layer 152C. Note that when a negative photosensitive material is used for the insulating film 127f, visible light or ultraviolet light is irradiated to the region where the insulating layer 127 will be formed.

[0373] By means of the exposed region of the insulating film 127f, the width of the insulating layer 127 to be formed later can be controlled. In the present embodiment, processing is performed such that the insulating layer 127 has a portion overlapping the top surface of the conductive layer 151.

[0374] The light used for exposure preferably has an i-line (wavelength 365 nm). In addition, the light used for exposure may also have at least one of a g-line (wavelength 436 nm) and an h-line (wavelength 405 nm).

[0375] Here, by providing an oxygen barrier insulating layer (such as an alumina film, etc.) as one or both of the sacrificial layers 158 (sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B) and the inorganic insulating film 125f, oxygen diffusion into the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B can be suppressed. When light (visible light or ultraviolet light) is irradiated onto the organic compound layer, sometimes the organic compounds contained in the organic compound layer become excited states and promote reactions with oxygen in the atmosphere. Specifically, when light (visible light or ultraviolet light) is irradiated onto the organic compound layer in an oxygen-containing atmosphere, oxygen may bond to the organic compounds contained in the organic compound layer. By providing the sacrificial layer 158 and the inorganic insulating film 125f on the island-shaped organic compound layer, oxygen in the atmosphere bonding to the organic compounds contained in the organic compound layer can be suppressed.

[0376] Next, as Figure 10AAs shown, development is performed to remove the exposed areas of insulating film 127f, thereby forming insulating layer 127a. Insulating layer 127a is formed in an area sandwiched between any two of conductive layers 152R, 152G, and 152B, and in an area surrounding conductive layer 152C. When an acrylic resin is used for insulating film 127f, an alkaline solution, such as TMAH, can be used as a developer.

[0377] Next, residues left during development (so-called scum) may be removed. For example, the residues may be removed by ashing using oxygen plasma.

[0378] Alternatively, etching may be performed to adjust the surface height of the insulating layer 127a. The insulating layer 127a may also be processed by, for example, ashing using oxygen plasma. Furthermore, if a non-photosensitive material is used as the insulating film 127f, the surface height of the insulating film 127f may also be adjusted by, for example, ashing.

[0379] Then, if Figure 10B As shown, an etching process is performed using insulating layer 127a as a mask to remove a portion of inorganic insulating film 125f, thereby reducing the thickness of a portion of sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B. Thus, inorganic insulating layer 125 is formed under insulating layer 127a. Furthermore, the surfaces of the thinner portions of sacrificial layer 158R, sacrificial layer 158G, and sacrificial layer 158B are exposed. Hereinafter, the etching process using insulating layer 127a as a mask may be referred to as the first etching process.

[0380] The first etching process can be performed by dry etching or wet etching. When the inorganic insulating film 125f is deposited using the same material as the sacrificial layers 158R, 158G, and 158B, the first etching process can be performed at once, which is preferable.

[0381] By using the insulating layer 127 a having tapered side surfaces as a mask for etching, the side surfaces of the inorganic insulating layer 125 and the upper end portions of the side surfaces of the sacrificial layers 158R, 158G, and 158B can be tapered more easily.

[0382] When dry etching is performed, a chlorine-based gas is preferably used. As the chlorine-based gas, one gas selected from Cl2, BCl3, SiCl4, and CCl4, or a mixture of two or more thereof, can be used. Furthermore, one gas selected from oxygen, hydrogen, helium, and argon, or a mixture of two or more thereof, can be appropriately added to the chlorine-based gas. By utilizing dry etching, regions with reduced thickness in the sacrificial layers 158R, 158G, and 158B can be formed with excellent in-plane uniformity.

[0383] As a dry etching device, a dry etching device having a high-density plasma source can be used. For example, as a dry etching device having a high-density plasma source, an inductively coupled plasma (ICP: Inductively Coupled Plasma) etching device or the like can be used. Alternatively, a capacitively coupled plasma (CCP: Capacitively Coupled Plasma) etching device including parallel plate electrodes can be used. The capacitively coupled plasma etching device including parallel plate electrodes can also adopt a structure in which a high-frequency voltage is applied to one of the parallel plate electrodes. Alternatively, a structure in which multiple different high-frequency voltages are applied to one of the parallel plate electrodes can also be adopted. Alternatively, a structure in which a high-frequency voltage of the same frequency is applied to each of the parallel plate electrodes can also be adopted. Alternatively, a structure in which high-frequency voltages of different frequencies are applied to each of the parallel plate electrodes can also be adopted.

[0384] Furthermore, when dry etching is performed, byproducts generated during the dry etching may be deposited on the top and side surfaces of the insulating layer 127a. As a result, components in the etching gas, components in the inorganic insulating film 125f, and components in the sacrificial layers 158R, 158G, and 158B may be included in the insulating layer 127 after the display device is completed.

[0385] In addition, the first etching process is preferably performed using wet etching. By using a wet etching method, damage to the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B can be further reduced compared to the case of using a dry etching method. For example, wet etching can be performed using an alkaline solution. For example, TMAH, an alkaline solution, can be used for wet etching of an aluminum oxide film. In this case, wet etching can be performed using a coating method. When the inorganic insulating film 125f is deposited using the same material as the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B, the above-mentioned etching process can be performed at one time, which is preferred.

[0386] In the first etching process, the sacrificial layers 158R, 158G, and 158B are not completely removed, and the etching process is stopped with the thickness reduced. Thus, by leaving the corresponding sacrificial layers 158R, 158G, and 158B on the organic compound layers 103R, 103G, and 103B, damage to the organic compound layers 103R, 103G, and 103B can be prevented in subsequent processing steps.

[0387] Next, the entire substrate is preferably exposed to visible light or ultraviolet light to irradiate the insulating layer 127a. The energy density of this exposure is preferably higher than 0 mJ / cm 2and is 800 mJ / cm 2 Hereinafter, it is more preferably higher than 0 mJ / cm 2 and is 500 mJ / cm 2 Hereinafter. By performing such exposure after development, the transparency of the insulating layer 127a can sometimes be improved. In addition, sometimes the substrate temperature required for the heat treatment for deforming the insulating layer 127a into a tapered shape in the subsequent process can be reduced.

[0388] Here, by providing an oxygen barrier insulating layer (such as an alumina film or the like) as the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B, oxygen diffusion into the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B can be suppressed. When light (visible light or ultraviolet light) is irradiated onto the organic compound layer, sometimes the organic compounds contained in the organic compound layer become excited states and promote reactions with oxygen in the atmosphere. Specifically, when light (visible light or ultraviolet light) is irradiated onto the organic compound layer in an oxygen-containing atmosphere, oxygen may bond to the organic compounds contained in the organic compound layer. By providing the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B on the island-shaped organic compound layer, oxygen in the atmosphere bonding to the organic compounds contained in the organic compound layer can be suppressed.

[0389] Next, a heat treatment (also referred to as post-baking) is performed. By performing the heat treatment, the insulating layer 127a can be deformed into an insulating layer 127 ( Figure 10C ) having a tapered shape on its side surface. This heat treatment is performed at a temperature lower than the heat-resistant temperature of the organic compound layer. The heat treatment can be performed at a substrate temperature of 50°C or higher and 200°C or lower, preferably 60°C or higher and 150°C or lower, and more preferably 70°C or higher and 130°C or lower. The heating atmosphere can be either an air atmosphere or an inert gas. In addition, the heating atmosphere can be either an air atmosphere or a reduced-pressure atmosphere. In the heat treatment of this step, it is preferable to increase the substrate temperature compared to the heat treatment (pre-baking) after forming the insulating film 127f. Thereby, the adhesion between the insulating layer 127 and the inorganic insulating layer 125 can be improved, and the corrosion resistance of the insulating layer 127 can also be improved.

[0390] In the first etching process, by not completely removing the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B and leaving the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B in a state where the thickness is thinned, damage and deterioration of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B can be prevented during this heat treatment. Thereby, the reliability of the light-emitting device can be improved.

[0391] Note that depending on the material of the insulating layer 127 and the temperature, time, and atmosphere of the post-baking, sometimes a concave curved surface shape is formed on the side surface of the insulating layer 127. For example, the higher the temperature or the longer the time in the post-baking conditions, the more likely the shape of the insulating layer 127 is to change, and thus a concave curved surface shape is sometimes formed.

[0392] Next, as Figure 11A shown, the insulating layer 127 is used as a mask for an etching process to remove a part of the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B. Note that sometimes a part of the inorganic insulating layer 125 is also removed. Thereby, openings are respectively formed in the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B, and the top surfaces of the organic compound layer 103R, the organic compound layer 103G, the organic compound layer 103B, and the conductive layer 152C are exposed. Hereinafter, the etching process using the insulating layer 127 as a mask is sometimes referred to as the second etching process.

[0393] The end portion of the inorganic insulating layer 125 is covered by the insulating layer 127. In addition, Figure 11A an example is shown in which a part of the end portion of the sacrificial layer 158G (specifically, the tapered shape portion formed by the first etching process) is covered by the insulating layer 127 and the tapered shape portion formed by the second etching process is exposed.

[0394] When the first etching process is not performed and the etching processes of the inorganic insulating layer 125 and the mask layer are performed at once after the post-baking, sometimes the inorganic insulating layer 125 and the mask layer under the end portion of the insulating layer 127 disappear due to side etching to form a cavity. Due to this cavity, unevenness is generated on the surface of the common electrode 155, and disconnection is likely to occur in the common electrode 155. Even if the inorganic insulating layer 125 and the mask layer are side-etched to form a cavity after the first etching process, the cavity can be filled by the insulating layer 127 through the subsequent post-baking. Then, in the second etching process, the mask layer with a further reduced thickness is etched, so the amount of side etching is less, cavities are not easily formed, and the cavities that can be formed can also be extremely small. Therefore, the surface on which the common electrode 155 is formed can be made flatter.

[0395] The insulating layer 127 may also cover the entire end portion of the sacrificial layer 158G. For example, sometimes the end portion of the insulating layer 127 droops to cover the end portion of the sacrificial layer 158G. In addition, for example, sometimes the end portion of the insulating layer 127 contacts the top surface of at least one of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B. As described above, when the insulating layer 127a after development is not exposed, the shape of the insulating layer 127 is sometimes likely to change.

[0396] The second etching process is performed using wet etching. By using the wet etching method, damage to the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B can be reduced compared to the case of using the dry etching method. The wet etching can be performed using an alkaline solution such as TMAH.

[0397] On the other hand, when the second etching process is performed using the wet etching method, if there are gaps at the interfaces between the organic compound layer 103 and the sacrificial layer 158, between the organic compound layer 103 and the inorganic insulating layer 125, and between the organic compound layer 103 and the insulating layer 175 due to problems such as the adhesion between the organic compound layer 103 and other layers, the chemical solution used in the second etching process sometimes enters these gaps and contacts the pixel electrode. Here, when the chemical solution contacts both the conductive layer 151 and the conductive layer 152, sometimes the conductive layer with the lower natural potential of the conductive layer 151 and the conductive layer 152 corrodes due to galvanic corrosion. For example, when aluminum is used as the conductive layer 151 and indium tin oxide is used as the conductive layer 152, sometimes the conductive layer 152 corrodes. As a result, the yield of the display device sometimes decreases. In addition, the reliability of the display device sometimes decreases.

[0398] As described above, by forming the insulating layer 156 so as to have a region overlapping with the side surface of the conductive layer 151 and forming the insulating layer 156 so as to cover the conductive layer 151 and the conductive layer 152, disconnection of the inorganic insulating layer 125 can be prevented. Therefore, for example, it is possible to prevent the chemical solution from contacting the underlying structure such as the conductive layer 151 during the second etching process. Thereby, corrosion of the pixel electrode can be prevented.

[0399] As described above, by providing the insulating layer 127, the inorganic insulating layer 125, the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B, between each light-emitting device, it is possible to suppress poor connection due to disconnection in the common electrode 155 and an increase in resistance due to a portion with a relatively thin local thickness. Thereby, the display device according to one embodiment of the present invention can improve the display quality.

[0400] In addition, a heat treatment may also be performed after a part of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B is exposed. By this heat treatment, water contained in each organic compound layer and water adsorbed on the surface of each organic compound layer can be removed. In addition, the shape of the insulating layer 127 sometimes changes due to this heat treatment. Specifically, the insulating layer 127 sometimes expands so as to cover at least one of the end portions of the inorganic insulating layer 125, the end portions of the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B, and the top surfaces of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B.

[0401] When the temperature of the heat treatment is too low, water contained in each organic compound layer and water adsorbed on the surface of each organic compound layer cannot be removed. In addition, when the temperature of the heat treatment is too high, deterioration of the organic compound layer 103 and excessive change in the shape of the insulating layer 127 sometimes occur. Therefore, the heat treatment temperature is preferably higher than the temperature at which water dissociates from the organic compound layer 103 and lower than the glass transition temperature of the organic compound contained in the organic compound layer 103, and more preferably lower than the glass transition temperature of the organic compound contained in the top surface of the organic compound layer 103. Specifically, the substrate temperature is preferably 80°C or higher and 130°C or lower, more preferably 90°C or higher and 120°C or lower, further preferably 100°C or higher and 120°C or lower, and even more preferably 100°C or higher and 110°C or lower. The heating atmosphere can be either an air atmosphere or an inert gas. Note that the heating atmosphere can be an atmospheric pressure atmosphere or a reduced pressure atmosphere, and a reduced pressure atmosphere is preferably used to prevent re-adsorption of the water dissociated from the organic compound layer 103.

[0402] Through this heat treatment, water contained in each organic compound layer, water adsorbed on the surface of each organic compound layer, etc. can be sufficiently removed without deterioration of the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B and excessive change in the shape of the insulating layer 127. Thereby, a decrease in the characteristics of the light-emitting device can be prevented.

[0403] Next, as Figure shown, a common layer 104 and a common electrode 155 are formed on the organic compound layer 103R, the organic compound layer 103G, the organic compound layer 103B, the conductive layer 152C, and the insulating layer 127. The common layer 104 and the common electrode 155 can be formed by a method such as sputtering or vacuum evaporation. Alternatively, the common layer 104 can be formed by evaporation and the common electrode 155 can be formed by sputtering.

[0404] Next, as ​ shown, a protective layer 131 is formed on the common electrode 155. The protective layer 131 can be formed by a method such as vacuum evaporation, sputtering, CVD, or ALD.

[0405] Next, the substrate 120 is bonded to the protective layer 131 using the resin layer 122, whereby a display device can be manufactured. As described above, in the method for manufacturing a display device according to one embodiment of the present invention, the insulating layer 156 is provided on the sides of the conductive layer 151 and the conductive layer 152. Thereby, the yield of the display device can be improved and the occurrence of defects can be suppressed.

[0406] As described above, in the method for manufacturing a display device according to one embodiment of the present invention, the island-shaped organic compound layer 103R, the island-shaped organic compound layer 103G, and the island-shaped organic compound layer 103B are not formed using a high-precision metal mask but are formed by depositing a film on one surface and then processing it, so that the island-shaped layers can be formed with a uniform thickness. Moreover, a high-definition display device or a display device with a high aperture ratio can be achieved. In addition, even when the definition or aperture ratio is high and the distance between sub-pixels is extremely short, it is possible to suppress the contact between the organic compound layer 103R, the organic compound layer 103G, and the organic compound layer 103B in adjacent sub-pixels. Therefore, it is possible to suppress the occurrence of leakage current between sub-pixels. As a result, crosstalk can be prevented and a display device with an extremely high contrast can be achieved. In addition, a display device having good characteristics can be provided even when it includes a tandem light-emitting device manufactured by a lithography technique.

[0407] The structure of this embodiment can be used in appropriate combination with the structures of other embodiments.

[0408] Embodiment 4 In this embodiment, with reference to ​ and ​ a light-emitting device according to one embodiment of the present invention will be described.

[0409] [Layout of pixels] In this embodiment, a pixel layout different from ​ will be mainly described. The arrangement of sub-pixels is not particularly limited, and various arrangement methods can be adopted. As the arrangement of sub-pixels, for example, stripe arrangement, S-stripe arrangement, matrix arrangement, delta arrangement, Bayer arrangement, and Pentile arrangement can be cited.

[0410] In this embodiment, the top surface shape of the sub-pixels shown in the drawings corresponds to the top surface shape of the light-emitting region.

[0411] In addition, as the top surface shape of the sub-pixels, for example, polygons such as triangles, quadrangles (including rectangles and squares), pentagons, etc., the above-mentioned polygonal shapes with rounded corners, ellipses, or circles can be cited.

[0412] In addition, the circuit layout constituting the sub-pixels is not limited to the range of the sub-pixels shown in the drawings, and can also be arranged outside thereof.

[0413] ​ The pixel 178 shown adopts an S-stripe arrangement. ​ The pixel 178 shown is composed of three sub-pixels: a sub-pixel 110R, a sub-pixel 110G, and a sub-pixel 110B.

[0414] ​The pixel 178 shown includes a sub-pixel 110R having a top surface shape of an approximate trapezoid or an approximate triangle with rounded corners, a sub-pixel 110G having a top surface shape of an approximate trapezoid or an approximate triangle with rounded corners, and a sub-pixel 110B having a top surface shape of an approximate quadrilateral or an approximate hexagon with rounded corners. Additionally, the light-emitting area of the sub-pixel 110R is larger than that of the sub-pixel 110G. Thus, the shapes and sizes of the respective sub-pixels can be determined independently. For example, the size of a sub-pixel including a highly reliable light-emitting device can be smaller.

[0415] ​ The pixels 124a and 124b shown adopt a Pentile arrangement. In ​ the example shown, pixels 124a including sub-pixels 110R and 110G and pixels 124b including sub-pixels 110G and 110B are alternately arranged.

[0416] ​ The pixels 124a and 124b shown adopt a Delta arrangement. Pixel 124a includes two sub-pixels (sub-pixels 110R and 110G) in the upper row (the first row) and one sub-pixel (sub-pixel 110B) in the lower row (the second row). Pixel 124b includes one sub-pixel (sub-pixel 110B) in the upper row (the first row) and two sub-pixels (sub-pixels 110R and 110G) in the lower row (the second row).

[0417] ​ An example is shown where each sub-pixel has a top surface shape of an approximate quadrilateral with rounded corners, ​ an example is shown where each sub-pixel has a circular top surface shape, ​ an example is shown where each sub-pixel has a hexagonal top surface shape.

[0418] In ​ each sub-pixel is arranged inside a hexagonal region arranged in a tight pattern. Each sub-pixel is arranged in such a way that when focusing on one sub-pixel, it is surrounded by six sub-pixels. In addition, it is arranged such that sub-pixels emitting light of the same color are not adjacent. For example, each sub-pixel is arranged such that when focusing on the sub-pixel 110R, it is surrounded by three sub-pixels 110G and three sub-pixels 110B arranged alternately.

[0419] ​ An example is shown where sub-pixels of each color are arranged in a zigzag shape. Specifically, when viewed from above, the positions of the upper sides of two sub-pixels arranged in the row direction (for example, sub-pixel 110R and sub-pixel 110G or sub-pixel 110G and sub-pixel 110B) are staggered.

[0420] In ​Among the pixels shown, for example, it is preferable that the sub-pixel 110R is a sub-pixel R that emits red light, the sub-pixel 110G is a sub-pixel G that emits green light, and the sub-pixel 110B is a sub-pixel B that emits blue light. Note that the structure of the sub-pixels is not limited to this, and the colors presented by the sub-pixels and their arrangement order can be appropriately determined. For example, the sub-pixel 110G can be set as the sub-pixel R that emits red light, and the sub-pixel 110R can be set as the sub-pixel G that emits green light.

[0421] In photolithography, the finer the pattern to be processed, the more the influence of light diffraction cannot be ignored. Therefore, when transferring the pattern of the photomask through exposure, its fidelity deteriorates, and it is difficult to process the resist mask into the desired shape. Therefore, even if the pattern of the photomask is rectangular, it is easy to form a pattern with rounded corners. Therefore, the top surface shape of the sub-pixels sometimes has a polygonal shape with rounded corners, an oval shape, or a circular shape, etc.

[0422] Moreover, in the manufacturing method of a light-emitting device according to one aspect of the present invention, the organic compound layer is processed into an island shape using a resist mask. The resist film formed on the organic compound layer needs to be cured at a temperature lower than the heat-resistant temperature of the organic compound layer. Therefore, depending on the heat-resistant temperature of the material of the organic compound layer and the curing temperature of the resist material, the curing of the resist film may sometimes be insufficient. An insufficiently cured resist film may sometimes have a shape that deviates from the desired shape when being processed. As a result, the top surface shape of the organic compound layer sometimes has a polygonal shape with rounded corners, an oval shape, or a circular shape, etc. For example, when a resist mask with a square top surface shape is to be formed, a resist mask with a circular top surface shape may sometimes be formed and the top surface shape of the organic compound layer is circular.

[0423] In order to make the top surface shape of the organic compound layer be the desired shape, a technique of pre-correcting the mask pattern in such a way that the designed pattern and the transferred pattern are consistent (OPC (Optical Proximity Correction) technique) can also be used. Specifically, in the OPC technique, for example, correction patterns are added to the graphic corners on the mask pattern.

[0424] As ​ shown, a pixel can include four types of sub-pixels.

[0425] ​ The pixel 178 shown adopts a stripe arrangement.

[0426] ​ An example is shown where each sub-pixel has a rectangular top surface shape. ​ An example is shown where each sub-pixel has a top surface shape connecting two semi-circles and a rectangle. ​ An example is shown where each sub-pixel has an oval top surface shape.

[0427] ​ The pixels 178 shown are arranged in a matrix.

[0428] ​ An example is shown in which each sub-pixel has a square top surface shape. ​ An example is shown in which each sub-pixel has an approximately square top surface shape with rounded corners. ​ An example is shown in which each sub-pixel has a circular top surface shape.

[0429] ​ and ​ An example is shown in which one pixel 178 is composed of two rows and three columns.

[0430] ​ The pixel 178 shown includes three sub-pixels (sub-pixel 110R, sub-pixel 110G, sub-pixel 110B) in the upper row (the first row) and one sub-pixel (sub-pixel 110W) in the lower row (the second row). In other words, the pixel 178 includes the sub-pixel 110R in the left column (the first column), the sub-pixel 110G in the central column (the second column), the sub-pixel 110B in the right column (the third column), and the sub-pixel 110W straddling these three columns.

[0431] ​ The pixel 178 shown includes three sub-pixels (sub-pixel 110R, sub-pixel 110G, sub-pixel 110B) in the upper row (the first row) and three sub-pixels 110W in the lower row (the second row). In other words, the pixel 178 includes the sub-pixel 110R and the sub-pixel 110W in the left column (the first column), the sub-pixel 110G and the sub-pixel 110W in the central column (the second column), and the sub-pixel 110B and the sub-pixel 110W in the right column (the third column). As ​ shown, by making the configurations of the sub-pixels in the upper and lower rows consistent, for example, dust that may be generated in the manufacturing process can be efficiently removed. Thereby, a light-emitting device with high display quality can be provided.

[0432] In ​ and ​ In the pixel 178 shown, the sub-pixels 110R, 110G, and 110B are arranged in a stripe pattern, so the display quality can be improved.

[0433] ​ ]>An example is shown in which one pixel 178 is composed of three rows and two columns.

[0434] ​The pixel 178 shown includes sub-pixel 110R in the upper row (the first row), sub-pixel 110G in the central row (the second row), sub-pixel 110B spanning the first row to the second row, and one sub-pixel (sub-pixel 110W) in the lower row (the third row). In other words, the pixel 178 includes sub-pixel 110R and sub-pixel 110G in the left column (the first column), sub-pixel 110B in the right column (the second column), and sub-pixel 110W spanning these two columns.

[0435] In ​ In the pixel 178 shown, the layout of sub-pixel 110R, sub-pixel 110G, and sub-pixel 110B is a so-called S stripe arrangement, so the display quality can be improved.

[0436] ​ The pixel 178 shown is composed of four sub-pixels: sub-pixel 110R, sub-pixel 110G, sub-pixel 110B, and sub-pixel 110W. For example, sub-pixel 110R can be set as a sub-pixel that emits red light, sub-pixel 110G can be set as a sub-pixel that emits green light, sub-pixel 110B can be set as a sub-pixel that emits blue light, and sub-pixel 110W can be set as a sub-pixel that emits white light. Additionally, at least one of sub-pixel 110R, sub-pixel 110G, sub-pixel 110B, and sub-pixel 110W can be set as a sub-pixel that emits cyan light, magenta light, yellow light, or near-infrared light.

[0437] As described above, in a light-emitting device according to one embodiment of the present invention, various layouts can be adopted for pixels composed of sub-pixels including light-emitting devices.

[0438] This embodiment can be appropriately combined with other embodiments or examples. In addition, in this specification, when multiple structural examples are shown in one embodiment, these structural examples can be appropriately combined.

[0439] Embodiment 5 In this embodiment, a display device according to one embodiment of the present invention will be described.

[0440] The display device of this embodiment can be a high-definition display device. Therefore, for example, the display device of this embodiment can be used as the display unit of information terminal devices (wearable devices) such as watch-type and bracelet-type devices, as well as the display unit of wearable devices that can be worn on the head, such as VR devices like head-mounted displays (HMDs) and glasses-type AR devices.

[0441] In addition, the display device of the present embodiment can be a high-resolution display device or a large display device. Therefore, for example, the display device of the present embodiment can be used as the display unit of the following devices: electronic devices with a large screen such as television devices, desktop or notebook personal computers, monitors for computers, etc., digital signage, and large game machines such as pachinko machines; digital cameras; digital video cameras; digital photo frames; mobile phones; portable game machines; portable information terminals; and sound reproduction devices.

[0442] [Display module] ​ A perspective view showing the display module 280. The display module 280 includes a display device 100A and an FPC 290. Note that the display device included in the display module 280 is not limited to the display device 100A, and can also be any one of the display devices 100B to 100E to be described later.

[0443] The display module 280 includes a substrate 291 and a substrate 292. The display module 280 includes a display unit 281. The display unit 281 is the image display area in the display module 280, and is an area where light from each pixel provided in the following pixel unit 284 can be seen.

[0444] ​ It is a perspective schematic diagram of the structure on the side of the substrate 291. A circuit unit 282 is laminated on the substrate 291, a pixel circuit unit 283 is laminated on the circuit unit 282, and a pixel unit 284 is laminated on the pixel circuit unit 283. In addition, a terminal unit 285 for connecting to the FPC 290 is provided on a portion of the substrate 291 that does not overlap with the pixel unit 284. The terminal unit 285 and the circuit unit 282 are electrically connected through a wiring unit 286 composed of a plurality of wirings.

[0445] The pixel unit 284 includes a plurality of pixels 284a arranged periodically. ​ An enlarged view of one pixel 284a is shown on the right side. The pixel 284a can adopt various structures described in the above embodiment.

[0446] The pixel circuit unit 283 includes a plurality of pixel circuits 283a arranged periodically.

[0447] One pixel circuit 283a controls the driving of a plurality of elements included in one pixel 284a.

[0448] The circuit unit 282 includes a circuit for driving each pixel circuit 283a of the pixel circuit unit 283. For example, it preferably includes one or both of a gate line driving circuit and a source line driving circuit. In addition, it can also have at least one of an arithmetic circuit, a storage circuit, and a power supply circuit, etc.

[0449] The FPC 290 is used as a wiring for supplying a video signal, a power potential, etc. from the outside to the circuit section 282. In addition, an IC can be mounted on the FPC 290.

[0450] The display module 280 may adopt a structure in which one or both of the pixel circuit section 283 and the circuit section 282 are stacked on the lower side of the pixel section 284, so that the display section 281 can have an extremely high aperture ratio (effective display area ratio).

[0451] The above-mentioned display module 280 has extremely high clarity, so it can be suitably used for VR devices such as HMDs or glasses-type AR devices. For example, in the structure of viewing the display section of the display module 280 through a lens, since the display module 280 has a display section 281 with extremely high clarity, even if the user magnifies the display section with the lens, pixels cannot be seen, and thus a display with a high sense of immersion can be achieved. In addition, the display module 280 is not limited to this, and can also be applied to electronic devices having a relatively small display section.

[0452] [Display device 100A] ​ The shown display device 100A includes a substrate 301, a light-emitting device 130R, a light-emitting device 130G, a light-emitting device 130B, a capacitor 240, and a transistor 310.

[0453] The substrate 301 corresponds to ​ and ​ the substrate 291 in . The transistor 310 is a transistor having a channel formation region in the substrate 301. As the substrate 301, for example, a semiconductor substrate such as a single-crystalline silicon substrate can be used. The transistor 310 includes a part of the substrate 301, a conductive layer 311, a low-resistance region 312, an insulating layer 313, and an insulating layer 314. The conductive layer 311 is used as a gate electrode. The insulating layer 313 is located between the substrate 301 and the conductive layer 311 and is used as a gate insulating layer. The low-resistance region 312 is a region in the substrate 301 doped with impurities and is used as a source or a drain. The insulating layer 314 covers the side surface of the conductive layer 311.

[0454] In addition, an element isolation layer 315 is provided in a manner of being embedded in the substrate 301 between two adjacent transistors 310.

[0455] In addition, an insulating layer 261 is provided to cover the transistor 310, and a capacitor 240 is provided on the insulating layer 261.

[0456] The capacitor 240 includes a conductive layer 241, a conductive layer 245, and an insulating layer 243 disposed therebetween. The conductive layer 241 is used as one electrode in the capacitor 240, the conductive layer 245 is used as the other electrode in the capacitor 240, and the insulating layer 243 is used as the dielectric of the capacitor 240.

[0457] The conductive layer 241 is disposed on the insulating layer 261 and embedded in the insulating layer 254. The conductive layer 241 is electrically connected to one of the source and drain of the transistor 310 through a plug 271 embedded in the insulating layer 261. The insulating layer 243 is disposed so as to cover the conductive layer 241. The conductive layer 245 is disposed in a region overlapping the conductive layer 241 with the insulating layer 243 therebetween.

[0458] An insulating layer 255 is disposed so as to cover the capacitor 240. An insulating layer 174 is disposed on the insulating layer 255, and an insulating layer 175 is disposed on the insulating layer 174. Light-emitting devices 130R, 130G, and 130B are disposed on the insulating layer 175. Insulators are disposed in regions between adjacent light-emitting devices.

[0459] An insulating layer 156R is disposed so as to include a region overlapping the side surface of the conductive layer 151R, an insulating layer 156G is disposed so as to include a region overlapping the side surface of the conductive layer 151G, and an insulating layer 156B is disposed so as to include a region overlapping the side surface of the conductive layer 151B. In addition, a conductive layer 152R is disposed so as to cover the conductive layer 151R and the insulating layer 156R, a conductive layer 152G is disposed so as to cover the conductive layer 151G and the insulating layer 156G, and a conductive layer 152B is disposed so as to cover the conductive layer 151B and the insulating layer 156B. A sacrificial layer 158R is located on the organic compound layer 103R, a sacrificial layer 158G is located on the organic compound layer 103G, and a sacrificial layer 158B is located on the organic compound layer 103B.

[0460] The conductive layers 151R, 151G, and 151B are electrically connected to one of the source and drain of the transistor 310 through plugs 256 embedded in the insulating layers 243, 255, 174, and 175, the conductive layer 241 embedded in the insulating layer 254, and the plug 271 embedded in the insulating layer 261. Various conductive materials can be used for the plugs.

[0461] In addition, a protective layer 131 is disposed on the light-emitting devices 130R, 130G, and 130B. A substrate 120 is bonded to the protective layer 131 with a resin layer 122. Details of the components from the light-emitting devices 130 to the substrate 120 can be referred to in Embodiment 4. The substrate 120 corresponds to ​ the substrate 292.

[0462] ​ shows ​ a modified example of the display device 100A shown. ​ The display device shown includes a coloring layer 132R, a coloring layer 132G, and a coloring layer 132B, and the light-emitting device 130 has a region overlapping one of the coloring layer 132R, the coloring layer 132G, and the coloring layer 132B. In ​ the display device shown, the light-emitting device 130 can emit white light, for example. In addition, for example, the coloring layer 132R, the coloring layer 132G, and the coloring layer 132B can transmit red light, green light, and blue light, respectively.

[0463] [Display device 100B] ​ shows a perspective view of the display device 100B, ​ shows a cross-sectional view of the display device 100C.

[0464] The display device 100B has a structure in which a bonding substrate 352 and a substrate 351 are bonded. In ​ this, the substrate 352 is shown by a dashed line.

[0465] The display device 100B includes a pixel portion 177, a connection portion 140, a circuit 356, wirings 355, etc. ​ shows an example in which the display device 100B is mounted with an IC 354 and an FPC 353. Therefore, ​ the structure shown can also be referred to as a display module including the display device 100B, an IC (integrated circuit), and an FPC. Here, the substrate of the display device on which a connector such as an FPC is mounted or the substrate on which an IC is mounted is called a display module.

[0466] The connection portion 140 is provided outside the pixel portion 177. The connection portion 140 can be one or more. In the connection portion 140, a common electrode of the light-emitting device is electrically connected to a conductive layer, and a potential can be supplied to the common electrode.

[0467] As the circuit 356, for example, a scan line driving circuit can be used.

[0468] The wiring 355 has a function of supplying signals and power to the pixel portion 177 and the circuit 356. The signals and power are input to the wiring 355 from the outside via the FPC 353 or input to the wiring 355 from the IC 354.

[0469] ​An example of setting the IC 354 on the substrate 351 by means of COG (Chip On Glass) or COF (Chip On Film) is shown. As the IC 354, for example, an IC including a scan line driving circuit or a signal line driving circuit can be used. Note that the display device 100B and the display module do not necessarily have to be provided with an IC. In addition, for example, the IC can also be mounted on the FPC by means of COF.

[0470] ​ An example of a cross-section of a part of the area including the FPC 353, a part of the circuit 356, a part of the pixel portion 177, a part of the connection portion 140, and a part of the area including the end portion of the display device 100B in the display device 100C is shown. ​

[0471] [Display device 100C] ​ The display device 100C shown includes a transistor 201, a transistor 205, a light-emitting device 130R that emits red light, a light-emitting device 130G that emits green light, and a light-emitting device 130B that emits blue light, etc. between the substrate 351 and the substrate 352.

[0472] Details of the light-emitting device 130R, the light-emitting device 130G, and the light-emitting device 130B can be referred to in Embodiment 4.

[0473] The light-emitting device 130R includes a conductive layer 224R, a conductive layer 151R on the conductive layer 224R, and a conductive layer 152R on the conductive layer 151R. The light-emitting device 130G includes a conductive layer 224G, a conductive layer 151G on the conductive layer 224G, and a conductive layer 152G on the conductive layer 151G. The light-emitting device 130B includes a conductive layer 224B, a conductive layer 151B on the conductive layer 224B, and a conductive layer 152B on the conductive layer 151B.

[0474] The conductive layer 224R is connected to the conductive layer 222b included in the transistor 205 through an opening provided in the insulating layer 214. The end portion of the conductive layer 151R is located outside the end portion of the conductive layer 224R. The insulating layer 156R is provided in such a way as to include a region in contact with the side surface of the conductive layer 151R, and the conductive layer 152R is provided so as to cover the conductive layer 151R and the insulating layer 156R.

[0475] The conductive layers 224G, 151G, 152G, and insulating layer 156G in the light-emitting device 130G, the conductive layers 224B, 151B, 152B, and insulating layer 156B in the light-emitting device 130B, and the conductive layers 224R, 151R, 152R, and insulating layer 156R in the light-emitting device 130R are the same, so detailed descriptions thereof are omitted.

[0476] Recesses are formed in the conductive layers 224R, 224G, and 224B so as to cover the openings provided in the insulating layer 214. The recesses are filled with the layer 128.

[0477] The layer 128 has a function of flattening the recesses of the conductive layers 224R, 224G, and 224B. The conductive layers 151R, 151G, and 151B electrically connected to the conductive layers 224R, 224G, and 224B are provided on the conductive layers 224R, 224G, 224B, and the layer 128. Therefore, the region overlapping with the recesses of the conductive layers 224R, 224G, and 224B can also be used as a light-emitting region, and the aperture ratio of the pixel can be increased.

[0478] The layer 128 can also be an insulating layer or a conductive layer. The layer 128 can appropriately use various inorganic insulating materials, organic insulating materials, and conductive materials. In particular, the layer 128 is preferably formed using an insulating material, and more preferably formed using an organic insulating material. For example, the layer 128 can use the organic insulating material that can be used for the insulating layer 127 described above.

[0479] A protective layer 131 is provided on the light-emitting devices 130R, 130G, and 130B. The protective layer 131 and the substrate 352 are bonded by the adhesive layer 142. A light-shielding layer 157 is provided on the substrate 352. The light-emitting device 130 can be sealed using a solid-sealing structure, a hollow-sealing structure, or the like. In ​ this case, the space between the substrate 352 and the substrate 351 is filled with the adhesive layer 142, that is, a solid-sealing structure is adopted. Alternatively, the space can also be filled with an inert gas (such as nitrogen or argon), that is, a hollow-sealing structure is adopted. At this time, the adhesive layer 142 can also be provided in a manner that does not overlap with the light-emitting device. In addition, the space can also be filled with a resin different from the adhesive layer 142 provided in a frame shape.

[0480] ​An example is shown below: The connection part 140 includes a conductive layer 224C obtained by processing a conductive film identical to the conductive layers 224R, 224G, and 224B, a conductive layer 151C obtained by processing a conductive film identical to the conductive layers 151R, 151G, and 151B, and a conductive layer 152C obtained by processing a conductive film identical to the conductive layers 152R, 152G, and 152B. In addition, ​ An example is shown in which the insulating layer 156C is provided in such a manner as to include a region overlapping with the side surface of the conductive layer 151C.

[0481] The display device 100C is a top-emission structure display device. The light-emitting device emits light to the side of the substrate 352. The substrate 352 is preferably made of a material with high visible light transmittance. The pixel electrode contains a material that reflects visible light, and the counter electrode (common electrode 155) contains a material that transmits visible light.

[0482] An insulating layer 211, an insulating layer 213, an insulating layer 215, and an insulating layer 214 are sequentially provided on the substrate 351. A part of the insulating layer 211 is used as a gate insulating layer for each transistor. A part of the insulating layer 213 is used as a gate insulating layer for each transistor. The insulating layer 215 is provided so as to cover the transistors. The insulating layer 214 is provided so as to cover the transistors and is used as a planarization layer. In addition, there is no particular limitation on the number of gate insulating layers and the number of insulating layers covering the transistors, and it may be one or two or more.

[0483] Preferably, an inorganic insulating film is used as the insulating layer 211, the insulating layer 213, and the insulating layer 215.

[0484] Preferably, an organic insulating layer is used as the insulating layer 214 serving as a planarization layer.

[0485] The transistors 201 and 205 include: a conductive layer 221 serving as a gate; an insulating layer 211 serving as a gate insulating layer; conductive layers 222a and 222b serving as source and drain electrodes; a semiconductor layer 231; an insulating layer 213 serving as a gate insulating layer; and a conductive layer 223 serving as a gate.

[0486] A connection portion 204 is provided in a region of the substrate 351 that does not overlap with the substrate 352. In the connection portion 204, a source electrode or a drain electrode of the transistor 201 is electrically connected to the FPC 353 through the conductive layer 166 and the connection layer 242. The following example is shown: The conductive layer 166 has a laminated structure of a conductive film obtained by processing a conductive film identical to the conductive layer 224R, the conductive layer 224G, and the conductive layer 224B, a conductive film obtained by processing a conductive film identical to the conductive layer 151R, the conductive layer 151G, and the conductive layer 151B, and a conductive film obtained by processing a conductive film identical to the conductive layer 152R, the conductive layer 152G, and the conductive layer 152B. The conductive layer 166 is exposed on the top surface of the connection portion 204. Therefore, the connection portion 204 can be electrically connected to the FPC 353 through the connection layer 242.

[0487] Preferably, a light-shielding layer 157 is provided on the surface of the substrate 352 on the side of the substrate 351. The light-shielding layer 157 can be provided between adjacent light-emitting devices, in the connection portion 140, the circuit 356, etc. In addition, various optical members can be arranged outside the substrate 352.

[0488] Each of the substrate 351 and the substrate 352 can adopt a material that can be used for the substrate 120.

[0489] As the adhesive layer 142, a material that can be used for the resin layer 122 can be used.

[0490] As the connection layer 242, an anisotropic conductive film (ACF: Anisotropic Conductive Film), an anisotropic conductive paste (ACP: Anisotropic Conductive Paste), etc. can be used.

[0491] [Display device 100D] ​ The shown display device 100D and ​ The main difference from the shown display device 100C is that the display device 100D is a bottom-emission structure display device.

[0492] The light-emitting device emits light to the side of the substrate 351. The substrate 351 preferably uses a material with high transmittance to visible light. On the other hand, there is no limitation on the light transmittance of the material used for the substrate 352.

[0493] Preferably, a light-shielding layer 317 is formed between the substrate 351 and the transistor 201 and between the substrate 351 and the transistor 205. ​ An example is shown in which a light-shielding layer 317 is provided on the substrate 351, an insulating layer 153 is provided on the light-shielding layer 317, and transistors 201, 205, etc. are provided on the insulating layer 153.

[0494] The light-emitting device 130R includes a conductive layer 112R, a conductive layer 126R on the conductive layer 112R, and a conductive layer 129R on the conductive layer 126R.

[0495] The light-emitting device 130B includes a conductive layer 112B, a conductive layer 126B on the conductive layer 112B, and a conductive layer 129B on the conductive layer 126B.

[0496] The conductive layers 112R, 112B, 126R, 126B, 129R, and 129B all use materials with high transmittance to visible light. As the second electrode 102, a material that reflects visible light is preferably used.

[0497] Note that although ​ the light-emitting device 130G is not shown in the figure, the light-emitting device 130G is also provided.

[0498] In addition, ​ examples such as those showing that the top surface of the layer 128 has a flat portion are shown, but the shape of the layer 128 is not particularly limited.

[0499] [Display device 100D2] ​ The shown display device 100D2 is an example of a display device with a bottom emission structure different from that of ​ the shown display device 100D. The difference between the display device 100D2 and the display device 100D is that the former includes an organic resin layer 180. ​ The shown display device 100D2 includes a substrate 351, a light-emitting device 130R, and a light-emitting device 130W. Note that in the drawings, the symbols of the same components as those in ​ are sometimes omitted, and the detailed content can be referred to ​ for the description.

[0500] In addition, ​ the top surface layout of the pixel 178 (pixel 178a and pixel 178b) including the sub-pixels 110 (sub-pixel 110R, sub-pixel 110G, sub-pixel 110B, sub-pixel 110W) is shown, ​ the top view of the organic resin layer 180 in the region where the sub-pixels 110R and 110G included in the pixel 178 are formed is shown. In addition, the width 110Rw in the light-emitting region of the sub-pixel 110R is between the light-shielding layers 317 and 317.

[0501] As ​ shown, the organic resin layer 180 is provided on the insulating layer 214. As ​ the region surrounded by the dotted line in ​As shown, the organic resin layer 180 includes concave portions 181 (concave portion 181a, concave portion 181b) having a curved surface at least in the region where sub-pixels are formed. In addition, the concave portion 181 may be provided outside the light-emitting region like the concave portion 181c. By providing the concave portion 181c, the light generated in the region overlapping the light-shielding layer 317 or the light entering the region overlapping the light-shielding layer 317 is refracted, and it can be extracted from the light-emitting region, thereby improving the light-emitting efficiency.

[0502] The plurality of concave portions 181 may also be formed in a matrix shape. The concave portion 181a and the concave portion 181b may be provided in contact with each other or may be provided with a flat surface therebetween.

[0503] In addition, although ​ it is shown that the top surface shape of the concave portion is hexagonal ( ​ ) and the cross-sectional shape is semi-circular ( ​ ), other shapes may be adopted as needed. For example, as the top surface shape of the concave portion, polygons such as triangles, quadrilaterals (including rectangles, squares), pentagons, etc., shapes in which the corners of the above polygons are rounded, ellipses or circles, etc. can be cited.

[0504] As the organic resin layer 180, an insulating layer containing an organic material can be used. For example, as the organic resin layer 180, acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimide amide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenolic resin, and precursors of the above resins, etc. can be used. In addition, as the organic resin layer 180, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinyl pyrrolidone, polyethylene glycol, polyglycerol, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin can also be used.

[0505] In addition, as the organic resin layer 180, a photosensitive resin can be used. As the photosensitive resin, a photoresist can also be used. The photosensitive resin can use a positive-type material or a negative-type material.

[0506] The organic resin layer 180 may also contain a material that absorbs visible light. For example, the organic resin layer 180 itself may be composed of a material that absorbs visible light, and the organic resin layer 180 may also contain a pigment that absorbs visible light. As the organic resin layer 180, for example, the following resins can be used: resins that can be used as color filters that transmit red light, blue light, or green light and absorb light of other colors; or resins that contain carbon black as a pigment and are used as black matrices; etc.

[0507] In addition, a first electrode 101 (first electrodes 101R and 101W) is provided on the organic resin layer 180, and an organic compound layer 103 is provided on the first electrode 101. The ends of the first electrode 101 and the organic compound layer 103 may also be covered by an insulating layer 127.

[0508] In addition, the first electrode 101 formed on the organic resin layer 180 has a recess in the same manner as the recess of the organic resin layer 180. The organic compound layer 103 formed on the first electrode 101 has a recess in the same manner as the recess of the first electrode 101. The common layer 104 formed on the organic compound layer 103 has a recess in the same manner as the recess of the organic compound layer 103. Further, the second electrode 102 formed on the common layer 104 has a recess in the same manner as the recess of the common layer 104. In other words, the recesses of the organic resin layer 180, the first electrode 101, the organic compound layer 103, the common layer 104, and the second electrode 102 overlap each other.

[0509] In addition, a common layer 104 is provided on the organic compound layer 103 and the insulating layer 127, and a second electrode 102 is provided on the common layer 104. A protective layer 131 is provided on the second electrode 102 and is bonded to the substrate 352 with an adhesive layer 142 interposed therebetween.

[0510] Note that, although ​ the light-emitting devices 130G and 130B are not shown in

[0511] [Display device 100E] ​ The display device 100E shown ​ is a modified example of the display device 100C shown

[0512] The main difference between the display device 100E and the display device 100C is that the former includes a coloring layer 132R, a coloring layer 132G, and a coloring layer 132B. In the display device 100E, the light-emitting device 130 has a region overlapping one of the coloring layer 132R, the coloring layer 132G, and the coloring layer 132B. The coloring layer 132R, the coloring layer 132G, and the coloring layer 132B may be provided on the surface of the substrate 351 on the side of the substrate 352. The ends of the coloring layer 132R, the ends of the coloring layer 132G, and the ends of the coloring layer 132B may overlap the light-shielding layer 157.

[0513] In the display device 100E, the light-emitting device 130 can emit white light, for example. Additionally, for example, the color filter layer 132R, the color filter layer 132G, and the color filter layer 132B can transmit red light, green light, and blue light, respectively. Further, the display device 100E can also adopt a structure in which the color filter layer 132R, the color filter layer 132G, and the color filter layer 132B are provided between the protective layer 131 and the adhesive layer 142.

[0514] [Display device 100E2] ​ The shown display device 100E2 is ​ a modified example of the shown display device 100E, which includes microlenses 182 on the color filter layer 132R, the color filter layer 132G, and the color filter layer 132B. Note that in the drawings, the symbols of the same components as those in ​ may sometimes be omitted, and the detailed content can be referred to ​ the description of

[0515] Additionally, ​ shows a top view layout of pixels 178 (pixels 178a and 178b) including sub-pixels 110 (sub-pixels 110R, sub-pixels 110G, and sub-pixels 110B). ​ shows a plan view of the microlenses 182 in the region where the sub-pixels 110R and sub-pixels 110G included in the pixel 178 are formed. Note that the region where the common electrode 155 contacts the organic compound layer 103 is the width 110Gw in the light-emitting region of the sub-pixel 110G.

[0516] In ​ the shown display device 100E2, a planarization film 143 is provided on the protective layer 131, and the color filter layer 132R, the color filter layer 132G, and the color filter layer 132B are provided on the planarization film 144. The planarization film 144 is provided so as to cover the color filter layer 132R, the color filter layer 132G, and the color filter layer 132B. The microlenses 182 are provided on the planarization film 144.

[0517] Additionally, as ​ shown, it is preferable to provide the microlenses 182 for each sub-pixel in the region where the sub-pixels are formed.

[0518] Note that in ​ the top surface shape of the microlenses 182 is hexagonal, but other shapes can be adopted as needed. For example, as the top surface shape of the microlenses 182, polygons such as triangles, quadrilaterals (including rectangles and squares), pentagons, etc., shapes in which the corners of the above polygons are rounded, ellipses, or circles can be cited.

[0519] The microlenses 182 can be formed using the same material as the organic resin layer 180.

[0520] This embodiment can be appropriately combined with other embodiments or examples. In addition, in this specification, when multiple structural examples are shown in one embodiment, the structural examples can be appropriately combined.

[0521] Embodiment 6 In this embodiment, an electronic device of one aspect of the present invention will be described.

[0522] The electronic device of this embodiment includes a light-emitting device of one aspect of the present invention in a display unit. The light-emitting device of one aspect of the present invention has high reliability and is easily high-definition and high-resolution. Therefore, it can be used for the display units of various electronic devices.

[0523] Examples of the electronic device include, in addition to electronic devices with a relatively large screen such as a television set, a desktop or notebook personal computer, a monitor for a computer, a digital signage, a large game machine such as a pachinko machine, a digital camera, a digital video camera, a digital photo frame, a mobile phone, a portable game machine, a portable information terminal, and a sound reproduction device.

[0524] In particular, since the light-emitting device of one aspect of the present invention can improve clarity, it can be appropriately used for electronic devices including a relatively small display unit. Examples of such electronic devices include watch-type and bracelet-type information terminal devices (wearable devices), wearable devices that can be worn on the head such as VR devices such as a head-mounted display, glasses-type AR devices, and MR (Mixed Reality) devices.

[0525] One embodiment of the light-emitting device of the present invention preferably has an extremely high resolution such as HD (number of pixels: 1280×720), FHD (number of pixels: 1920×1080), WQHD (number of pixels: 2560×1440), WQXGA (number of pixels: 2560×1600), 4K (number of pixels: 3840×2160), 8K (number of pixels: 7680×4320), etc. In particular, it is preferably set to a resolution of 4K, 8K or higher. In addition, the pixel density (clarity) of the light-emitting device according to one embodiment of the present invention is preferably 100 ppi or more, preferably 300 ppi or more, more preferably 500 ppi or more, further preferably 1000 ppi or more, still further preferably 2000 ppi or more, still further preferably 3000 ppi or more, even further preferably 5000 ppi or more, and further preferably 7000 ppi or more. By using the above light-emitting device having one or both of high resolution and high clarity, the sense of reality and the sense of depth can be further enhanced. In addition, there is no particular limitation on the screen ratio (aspect ratio) of the light-emitting device according to one embodiment of the present invention. For example, the light-emitting device can adapt to various screen ratios such as 1:1 (square), 4:3, 16:9, and 16:10.

[0526] The electronic device of the present embodiment may also include a sensor (the sensor has a function of measuring the following factors: force, displacement, position, speed, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, electric power, radiation, flow rate, humidity, inclination, vibration, odor, or infrared rays).

[0527] The electronic device of the present embodiment can have various functions. For example, it can have the following functions: a function of displaying various information (static images, dynamic images, text images, etc.) on the display unit; a function of a touch panel; a function of displaying a calendar, date, or time, etc.; a function of executing various software (programs); a function of performing wireless communication; a function of reading programs or data stored in a storage medium; etc.

[0528] Use ​ An example of a wearable device that can be worn on the head will be described. These wearable devices have at least one of a function of displaying AR content, a function of displaying VR content, a function of displaying SR (Substitutional Reality) content, and a function of displaying MR content. When the electronic device has a function of displaying at least one of AR, VR, SR, and MR content, the immersion of the user can be enhanced.

[0529] ​ The shown electronic device 700A and ​The illustrated electronic device 700B includes a pair of display panels 751, a pair of outer casings 721, a communication unit (not shown), a pair of mounting portions 723, a control unit (not shown), an imaging unit (not shown), a pair of optical members 753, a bezel 757, and a pair of nose pads 758.

[0530] The display panel 751 can apply the light-emitting device of one aspect of the present invention. Thereby, an electronic device with high reliability can be realized.

[0531] Both the electronic device 700A and the electronic device 700B can project the image displayed on the display panel 751 onto the display area 756 in the optical member 753. Since the optical member 753 has translucency, the user can view the image displayed in the display area overlapping with the transmitted image seen through the optical member 753. Therefore, both the electronic device 700A and the electronic device 700B are electronic devices capable of performing AR display.

[0532] On the electronic device 700A and the electronic device 700B, a camera capable of photographing the front can also be provided as the imaging unit. In addition, by providing an acceleration sensor such as a gyro sensor in the electronic device 700A and the electronic device 700B, the user's head orientation can be detected and the image corresponding to the direction can be displayed on the display area 756.

[0533] The communication unit has a wireless communication device, and an image signal can be supplied through the wireless communication device, for example. In addition, instead of or in addition to the wireless communication device, a connector capable of connecting a cable for supplying an image signal and a power potential may be included.

[0534] In addition, the electronic device 700A and the electronic device 700B are provided with a battery and can be charged in one or both of a wireless manner and a wired manner.

[0535] The outer casing 721 may also be provided with a touch sensor module. The touch sensor module has a function of detecting whether the outer surface of the outer casing 721 is touched. Through the touch sensor module, various processes can be executed by detecting the user's tapping operation or swiping operation, etc. For example, through the tapping operation, processes such as temporarily stopping or playing a moving image can be executed, and through the swiping operation, processes such as fast forward and rewind can be executed, etc. In addition, by providing a touch sensor module on each of the two outer casings 721, the operation range can be expanded.

[0536] As the touch sensor module, various touch sensors can be used. For example, various methods such as the capacitive method, the resistive film method, the infrared method, the electromagnetic induction method, the surface acoustic wave method, and the optical method can be adopted. In particular, it is preferable to apply a capacitive method or optical method sensor to the touch sensor module.

[0537] When using an optical touch sensor, a photoelectric conversion device (also referred to as a photoelectric conversion element) can be used as a light-receiving element. One or both of an inorganic semiconductor and an organic semiconductor can be used in the active layer of the photoelectric conversion device.

[0538] ​ The electronic device 800A shown and ​ The electronic device 800B shown both include a pair of display units 820, a housing 821, a communication unit 822, a pair of mounting units 823, a control unit 824, a pair of imaging units 825, and a pair of lenses 832.

[0539] The display unit 820 can apply the light-emitting device of one aspect of the present invention. Thus, a highly reliable electronic device can be realized.

[0540] The display unit 820 is provided at a position inside the housing 821 where it can be seen through the lens 832. In addition, by displaying different images on each of the pair of display units 820, three-dimensional display using parallax can be performed.

[0541] Both the electronic device 800A and the electronic device 800B can be referred to as VR-oriented electronic devices. A user wearing the electronic device 800A or the electronic device 800B can see the image displayed on the display unit 820 through the lens 832.

[0542] The electronic device 800A and the electronic device 800B preferably have a mechanism in which the left and right positions of the lens 832 and the display unit 820 can be adjusted so that the lens 832 and the display unit 820 are located at the most suitable positions according to the position of the user's eyes. In addition, it preferably has a mechanism in which the focus is adjusted by changing the distance between the lens 832 and the display unit 820.

[0543] The user can mount the electronic device 800A or the electronic device 800B on the head using the mounting unit 823. For example, in ​ it, the mounting unit 823 has a shape like the temple of glasses (also referred to as the temple wire), but is not limited thereto. As long as the user can mount it, the mounting unit 823 can have, for example, a helmet type or a band type shape.

[0544] The imaging unit 825 has a function of acquiring external information. The data acquired by the imaging unit 825 can be output to the display unit 820. An image sensor can be used in the imaging unit 825. In addition, multiple cameras can also be provided to be able to correspond to various perspectives such as telephoto and wide-angle.

[0545] Note that an example including the imaging unit 825 is shown here, and a distance measurement sensor (hereinafter, also referred to as a detection unit) capable of measuring the distance to an object may be provided. In other words, the imaging unit 825 is one mode of the detection unit. As the detection unit, for example, an image sensor or a distance image sensor such as a lidar (Light Detection and Ranging) can be used. By using the image obtained by the camera and the image obtained by the distance image sensor, more information can be obtained, and a more accurate attitude operation can be achieved.

[0546] The electronic device 800A may also include a vibration mechanism used as a bone conduction headphone. For example, as any one or more of the display unit 820, the housing 821, and the mounting unit 823, a structure including the vibration mechanism may be adopted. Thus, there is no need to separately provide audio devices such as a headset, headphones, or speakers, and the user can enjoy images and sounds just by attaching the electronic device 800A.

[0547] Both the electronic device 800A and the electronic device 800B may include input terminals. For example, a cable for supplying an image signal from an image output device or the like and power for charging a battery provided in the electronic device can be connected to the input terminals.

[0548] An electronic device according to one aspect of the present invention may also have a function of wirelessly communicating with the headphone 750. The headphone 750 includes a communication unit (not shown) and has a wireless communication function. The headphone 750 can receive information (such as sound data) from the electronic device through the wireless communication function. For example, ​ The illustrated electronic device 700A has a function of transmitting information to the headphone 750 through the wireless communication function. Additionally, for example, ​ The illustrated electronic device 800A has a function of transmitting information to the headphone 750 through the wireless communication function.

[0549] In addition, the electronic device may also include a headphone unit. ​ The illustrated electronic device 700B includes a headphone unit 727. For example, a structure in which the headphone unit 727 and the control unit are connected in a wired manner may be adopted. A part of the wiring connecting the headphone unit 727 and the control unit may also be arranged inside the housing 721 or the mounting unit 723.

[0550] Similarly, ​The illustrated electronic device 800B includes a headphone unit 827. For example, a structure in which the headphone unit 827 and the control unit 824 are connected in a wired manner can be adopted. A part of the wiring connecting the headphone unit 827 and the control unit 824 can also be disposed inside the housing 821 or the mounting portion 823. In addition, the headphone unit 827 and the mounting portion 823 may include magnets. Thus, it is possible to fix the headphone unit 827 to the mounting portion 823 with magnetic force, making storage easier, so it is preferable.

[0551] The electronic device may also include a sound output terminal capable of connecting to a headphone or a headset. In addition, the electronic device may include one or both of a sound input terminal and a sound input mechanism. As the sound input mechanism, for example, a sound collection device such as a microphone can be used. By providing the sound input mechanism to the electronic device, the electronic device can have the function of a so-called headset.

[0552] Thus, as an electronic device according to one aspect of the present invention, both the glasses type (such as the electronic devices 700A and 700B) and the goggles type (such as the electronic devices 800A and 800B) are preferable.

[0553] In addition, an electronic device according to one aspect of the present invention can transmit information to a headphone in a wired or wireless manner.

[0554] ​ The illustrated electronic device 6500 is a portable information terminal device that can be used as a smartphone.

[0555] The electronic device 6500 includes a housing 6501, a display unit 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, a light source 6508, etc. The display unit 6502 has a touch panel function.

[0556] The display unit 6502 can use a light-emitting device according to one aspect of the present invention. Thus, a highly reliable electronic device can be realized.

[0557] ​ It is a cross-sectional schematic view of an end portion on the microphone 6506 side including the housing 6501.

[0558] A protective member 6510 having translucency is provided on the display surface side of the housing 6501, and a display panel 6511, an optical member 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are provided in a space surrounded by the housing 6501 and the protective member 6510.

[0559] The display panel 6511, the optical member 6512, and the touch sensor panel 6513 are fixed to the protective member 6510 using an adhesive layer (not shown).

[0560] In the region outside the display unit 6502, a part of the display panel 6511 is folded back, and an FPC 6515 is connected to the folded-back part. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to a terminal provided on the printed circuit board 6517.

[0561] The display panel 6511 can use the light-emitting device of one mode of the present invention. Thus, an extremely lightweight electronic device can be realized. In addition, since the display panel 6511 is extremely ...

Claims

1. A light-emitting device, comprising: A first electrode; A second electrode; And An organic compound layer, Wherein the organic compound layer is located between the first electrode and the second electrode, The organic compound layer at least includes a light-emitting layer and an electron injection layer, The electron injection layer contains a first organic compound including a phenanthroline skeleton having an electron-donating group, The water solubility of the first organic compound in pure water is 20 mg / L or less and the glass transition temperature is 80 °C or higher, And, when viewed from above, the contour of the light-emitting layer coincides with or is substantially consistent with the contour of the electron injection layer.

2. A light-emitting device, comprising: A first electrode; A second electrode; And An organic compound layer, Wherein the organic compound layer is located between the first electrode and the second electrode, The organic compound layer at least includes a light-emitting layer and an electron injection layer, The electron injection layer is in contact with the second electrode, The electron injection layer contains a first organic compound including a phenanthroline skeleton having an electron-donating group, The first organic compound interacts with the second electrode, The water solubility of the first organic compound in pure water is 20 mg / L or less and the glass transition temperature is 80 °C or higher, And, when viewed from above, the contour of the light-emitting layer coincides with or is substantially consistent with the contour of the electron injection layer.

3. The light-emitting device according to claim 1, Wherein the phenanthroline skeleton is a 1,10-phenanthroline skeleton, And the electron-donating group is located at at least one of the 4-position and the 7-position of the 1,10-phenanthroline skeleton.

4. The light-emitting device according to claim 3, Wherein the electron-donating group is at least one of an alkyl group, an alkoxy group, an aryloxy group, an alkylamino group, an arylamino group, and a heterocyclic amino group.

5. The light-emitting device according to claim 1, Wherein the water solubility of the first organic compound in pure water is 0.1 mg / L or more and 10 mg / L or less.

6. The light-emitting device according to claim 1, Wherein the glass transition temperature of the first organic compound is 100 °C or higher.

7. The light-emitting device according to claim 1, wherein when the threshold value of the electron density distribution in atomic units is 0.0004 e / a0 3 the minimum value of the electrostatic potential of the first organic compound is -0.085 E h or less.

8. The light-emitting device according to claim 1, Wherein the acidity coefficient pKa of the first organic compound is 8 or more.

9. A light-emitting device, comprising: A first electrode; A second electrode; And An organic compound layer, Wherein the organic compound layer is located between the first electrode and the second electrode, The organic compound layer at least includes a light-emitting layer and an electron injection layer, The electron injection layer is in contact with the second electrode, The electron injection layer contains a first organic compound represented by structural formula (100): And, when viewed from above, the contour of the light-emitting layer coincides with or is substantially consistent with the contour of the electron injection layer.

10. The light-emitting device according to claim 1, Wherein the organic compound layer includes an electron transport layer between the light-emitting layer and the electron injection layer, The electron transport layer contains a second organic compound having a π-deficient heteroaromatic ring, And the LUMO energy level of the first organic compound is higher than the LUMO energy level of the second organic compound.

11. The light emitting device according to claim 10, The difference between the LUMO energy level of the first organic compound and the LUMO energy level of the second organic compound is 0.2 eV or more and 0.8 eV or less.

12. The light emitting device according to claim 1, The second electrode includes at least one of Ag, Mg and Al.

13. The light emitting device according to claim 2, The phenanthroline skeleton is a 1,10-phenanthroline skeleton. The electron-donating group is located at at least one of the 4-position and the 7-position of the 1,10-phenanthroline skeleton.

14. The light emitting device according to claim 13, The electron-donating group is at least one of an alkyl group, an alkoxy group, an aryloxy group, an alkylamino group, an arylamino group and a heterocyclic amino group.

15. The light emitting device according to claim 2, The solubility of the first organic compound in pure water is 0.1 mg / L or more and 10 mg / L or less.

16. The light emitting device according to claim 2, The glass transition temperature of the first organic compound is above 100°C.

17. The light emitting device according to claim 2, wherein when the threshold of the electron density distribution in the atomic unit system is 0.0004 e / a0 3 the minimum value of the electrostatic potential of the first organic compound is -0.085 E h or less.

18. The light emitting device according to claim 2, The acidity coefficient pKa of the first organic compound is greater than 8.

19. The light emitting device according to claim 9, wherein the organic compound layer includes an electron transport layer between the light emitting layer and the electron injection layer, The electron transport layer comprises a second organic compound having a π-electron-deficient heteroaromatic ring, And the LUMO energy level of the first organic compound is higher than the LUMO energy level of the second organic compound.

20. The light emitting device according to claim 19, The difference between the LUMO energy level of the first organic compound and the LUMO energy level of the second organic compound is 0.2 eV or more and 0.8 eV or less.

Images