Light-emitting elements, display devices, electronic devices, and lighting devices

Abstract

To provide a light-emitting element with high luminous efficiency and high reliability. [Solution] A light-emitting layer comprising a first organic compound, a second organic compound, and a guest material. This is a light-emitting element. The first organic compound has a nitrogen-containing six-membered heteroaromatic skeleton. In this, a nitrogen-containing five-membered heterocyclic skeleton, a secondary amine skeleton, or a primary amine skeleton having an NH group. The content of organic compounds including the first organic compound is 0.03 or less by weight relative to the first organic compound. The weight ratio to the second organic compound is 0.01 or less.

Description

[Technical Field]

[0001] One aspect of the present invention relates to a light-emitting element, or a display device having the light-emitting element, an electronic device, and a light Regarding lighting equipment.

[0002] Furthermore, one aspect of the present invention is not limited to the above-mentioned technical field. One aspect of the technical field relates to a product, method, or method of manufacture. Or, one aspect of the present invention. This refers to a process, machine, manufacture, or composition. Regarding the ter. Therefore, the technical aspects of one aspect of the present invention disclosed more specifically herein Examples include semiconductor devices, display devices, liquid crystal display devices, light-emitting devices, lighting devices, energy storage devices, and memory devices. Examples include devices, methods for driving them, or methods for manufacturing them. . [Background technology]

[0003] In recent years, electroluminescence (EL) Research and development of light-emitting devices using this technology are actively underway. The basic configuration of these light-emitting devices is The device has a configuration in which a layer containing a light-emitting material (EL layer) is sandwiched between a pair of electrodes. By applying a voltage between them, light emission can be obtained from the light-emitting material.

[0004] Since the aforementioned light-emitting element is self-illuminating, the display device using it offers excellent visibility and battery life. It has advantages such as not requiring crystalline materials and consuming less power. Furthermore, it can be manufactured to be thin and lightweight. It also has advantages such as a high response speed.

[0005] An organic compound is used as the luminescent material, and an EL layer containing the luminescent material is provided between a pair of electrodes. In the case of a light-emitting element (for example, an organic EL element), by applying a voltage between a pair of electrodes... Electrons are injected from the cathode and holes from the anode into the EL layer, and an electric current flows. Then, the injected electrons and holes recombine, causing the luminescent organic compound to be excited. This creates an excited state, and light emission can be obtained from the excited, luminescent organic compound.

[0006] The luminescence exhibited by luminescent organic compounds is unique to that particular organic compound. Therefore, By using various organic compounds as luminescent materials, light-emitting devices exhibiting various types of luminescence can be created. You can obtain this.

[0007] One of the important characteristics of such light-emitting elements is efficiency and reliability. Therefore, light emission It is important to reduce impurities that cause a decrease in the efficiency and reliability of the device. Reference 1 focuses on halogen compounds in an EL layer containing organic compounds, and keeps their concentration constant. The following is disclosed as a way to obtain a highly reliable light-emitting element. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] International Publication No. 00 / 41443 [Overview of the project] [Problems that the invention aims to solve]

[0009] While some impurities can degrade characteristics such as the efficiency and reliability of light-emitting elements, Some impurities do not affect the characteristics of the light-emitting element. Identifying the type of impurity is important. However, the impurities contained in the light-emitting element Because the content is small, it is often difficult to identify impurities. Also, impurities can cause luminescence. The mechanisms that degrade the characteristics of the device are largely unknown.

[0010] Therefore, one aspect of the present invention aims to provide a highly reliable light-emitting element. Alternatively, in one aspect of the present invention, one of the objectives is to provide a light-emitting element with high luminescence efficiency. Alternatively, in one aspect of the present invention, a light-emitting element with reduced power consumption is provided. One of the challenges is to provide a novel light-emitting element. Alternatively, in one aspect of the present invention, the challenge is to provide a novel light-emitting element. One aspect of the present invention is to provide a novel light-emitting device. Alternatively, in one aspect of the present invention, one objective is to provide a novel display device.

[0011] Furthermore, the description of the above problems does not preclude the existence of other problems. Also, one aspect of the present invention is not necessarily However, it is not necessary to solve all of these problems. Other issues not mentioned above should be described in the specification, etc. This is self-evident, and it is possible to extract issues other than those mentioned above from the description in the specification, etc. ru. [Means for solving the problem]

[0012] One aspect of the present invention is a light-emitting element having a light-emitting layer, wherein the light-emitting layer comprises a first organic compound and The first organic compound has a nitrogen-containing six-membered heteroaromatic skeleton and emits light. In the layer, a nitrogen-containing five-membered heterocyclic skeleton having an NH group, a secondary amine skeleton having an NH group, The content of an organic compound containing a primary amine skeleton having an NH group is the same as that of the first organic compound. This is a light-emitting element with a weight ratio of 0.03 or less.

[0013] Another aspect of the present invention is a light-emitting element having a light-emitting layer, wherein the light-emitting layer is a first The device comprises an organic compound and a guest material, wherein the first organic compound has a pyridine skeleton and a diazine skeleton. , or having at least one triazine skeleton, and in the light-emitting layer, a pillow having an NH group A skeleton, an imidazole skeleton having an NH group, a triazole skeleton having an NH group, an NH group Organic compounds containing a tetrazole skeleton or an aromatic amine skeleton having an NH group The light-emitting element is one in which the content is 0.03 or less by weight relative to the first organic compound.

[0014] Another aspect of the present invention is a light-emitting element having a light-emitting layer, wherein the light-emitting layer is a first The material comprises an organic compound, a second organic compound, and a guest material, wherein the first organic compound is nitrogen-containing. The second organic compound has a six-membered heteroaromatic skeleton, and the second organic compound has a nitrogen-containing five-membered heterocyclic skeleton or a tertiary amino acid. Having at least one of the n skeletons, and in the luminescent layer, a nitrogen-containing five-membered heterocyclic skeleton having an NH group, Organic compounds containing a secondary amine skeleton having an NH group, or a primary amine skeleton having an NH group The light-emitting element is one in which the content of the substance is 0.01 or less by weight relative to the second organic compound.

[0015] Another aspect of the present invention is a light-emitting element having a light-emitting layer, wherein the light-emitting layer is a first The material comprises a first organic compound, a second organic compound, and a guest material, wherein the first organic compound is pyridium A second organic compound having at least one of the following skeletons: a diazine skeleton, a diazine skeleton, or a triazine skeleton. These are pyrrole skeletons, imidazole skeletons, triazole skeletons, tetrazole skeletons, or aromatic skeletons. Having at least one aromatic amine skeleton, and in the luminescent layer, a pyrrole skeleton having an NH group, Imidazole skeleton having an NH group, triazole skeleton having an NH group, te The content of organic compounds containing a trazole skeleton or an aromatic amine skeleton having an NH group is The light-emitting element is present in a weight ratio of 0.01 or less to the second organic compound.

[0016] Furthermore, in each of the above configurations, the NH bond is released from the excited state of the organic compound having the NH group. The effect of one embodiment of the present invention is that the activation energy required for dissociation is 0.3 eV or less. It is large. Also, the stabilization energy when the NH bond in the NH group dissociates is 0 eV. When the value is less than the specified value, the effects of one aspect of the present invention are greater.

[0017] Furthermore, in each of the above configurations, the light-emitting layer has nitrogen atoms that have unpaired electrons, and is nitrogen-containing five-membered Organic compounds containing a heterocyclic skeleton or an aromatic amine skeleton in which the nitrogen atom has unpaired electrons Preferably, the content is 0.03 or less by weight ratio to the first organic compound. In the photolayer, the content of an organic compound in which a hydrogen atom is further bonded to the first organic compound is, Preferably, the weight ratio to the first organic compound is 0.03 or less.

[0018] Furthermore, in each of the above configurations, the light-emitting layer has nitrogen atoms that have unpaired electrons, and is nitrogen-containing five-membered Organic compounds containing a heterocyclic skeleton or an aromatic amine skeleton in which the nitrogen atom has unpaired electrons Preferably, the content is 0.01 or less by weight ratio to the second organic compound. In the photolayer, the content of an organic compound in which a hydrogen atom is further bonded to the first organic compound is, Preferably, the weight ratio to the second organic compound is 0.01 or less.

[0019] Furthermore, in each of the above configurations, the guest material converts the triplet excitation energy into light emission. It is preferable that the guest material has the ability to do so. Furthermore, it is preferable that the guest material contains iridium. stomach.

[0020] Another aspect of the present invention involves the light-emitting element of each of the above configurations and a color filter or transistor. A display device having at least one zista. Another aspect of the present invention is the said It is an electronic device having a display device and at least one of a housing or a touch sensor. Another aspect of the present invention relates to the light-emitting element of each of the above configurations and at least one housing or touch sensor. It is a lighting device having one and a light-emitting device. Another aspect of the present invention is a light-emitting device having a light-emitting element. Furthermore, electronic devices having light-emitting devices are also included in the scope. Therefore, the term "light" in this specification is also used. A light device refers to an image display device or a light source (including lighting devices). connectors, for example, FPC (Flexible Printed Circuit), Display module with TCP (Tape Carrier Package) attached , a display module with a printed circuit board located beyond the TCP, or a COG ( A display module with an IC (integrated circuit) directly mounted using the Chip-On-Glass (Chip-On-Glass) method. This is also one aspect of the present invention. [Effects of the Invention]

[0021] According to one aspect of the present invention, a highly reliable light-emitting element can be provided. A highly efficient light-emitting element can be provided. Alternatively, according to one aspect of the present invention, power consumption It is possible to provide a light-emitting element with reduced noise. Alternatively, according to one aspect of the present invention, a novel A light-emitting element can be provided. Alternatively, according to one aspect of the present invention, a novel light-emitting device can be provided. It can be provided. Or, according to one aspect of the present invention, a novel display device can be provided. can.

[0022] Furthermore, the description of these effects does not preclude the existence of other effects. One aspect of the present invention is: It is not necessarily required to have all of these effects. Other effects are described in the specification. This is obvious from the descriptions in the specifications, drawings, and claims, and the descriptions in the specifications, drawings, and claims Therefore, it is possible to extract effects other than those mentioned above. [Brief explanation of the drawing]

[0023] [Figure 1] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention. [Figure 2] A diagram illustrating a reaction according to one aspect of the present invention. [Figure 3] A diagram illustrating a reaction according to one aspect of the present invention. [Figure 4] A diagram illustrating a reaction according to one aspect of the present invention. [Figure 5] A diagram illustrating the correlation between LUMO levels and energy according to one aspect of the present invention. [Figure 6] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention, and a diagram illustrating the correlation of energy levels related to the light-emitting layer. [Figure 7] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention, and a diagram illustrating the correlation of energy levels related to the light-emitting layer. [Figure 8] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention, and a diagram illustrating the correlation of energy levels related to the light-emitting layer. [Figure 9] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention. [Figure 10] A schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention. [Figure 11] A schematic cross-sectional diagram illustrating a method for manufacturing a light-emitting element according to one embodiment of the present invention. [Figure 12] A schematic cross-sectional diagram illustrating a method for manufacturing a light-emitting element according to one embodiment of the present invention. [Figure 13] A top view and a schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 14]A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 15] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 16] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 17] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 18] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 19] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 20] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 21] A schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. [Figure 22] A schematic cross-sectional diagram illustrating the method for fabricating the EL layer. [Figure 23] A conceptual diagram illustrating a droplet dispensing device. [Figure 24] A block diagram and a circuit diagram illustrating a display device according to one embodiment of the present invention. [Figure 25] A circuit diagram illustrating the pixel circuit of a display device according to one embodiment of the present invention. [Figure 26] A circuit diagram illustrating the pixel circuit of a display device according to one embodiment of the present invention. [Figure 27] A perspective view showing an example of a touch panel according to one aspect of the present invention. [Figure 28] A cross-sectional view showing an example of a display device and a touch sensor according to one embodiment of the present invention. [Figure 29] A cross-sectional view showing an example of a touch panel according to one aspect of the present invention. [Figure 30] A block diagram and timing chart diagram of a touch sensor according to one aspect of the present invention. [Figure 31] Circuit diagram of a touch sensor according to one aspect of the present invention. [Figure 32] A perspective view illustrating a display module according to one embodiment of the present invention. [Figure 33] A diagram illustrating an electronic device according to one embodiment of the present invention. [Figure 34]A diagram illustrating an electronic device according to one embodiment of the present invention. [Figure 35] A diagram illustrating an electronic device according to one embodiment of the present invention. [Figure 36] A diagram illustrating an electronic device according to one embodiment of the present invention. [Figure 37] A perspective view illustrating a display device according to one embodiment of the present invention. [Figure 38] A perspective view and a cross-sectional view illustrating a light-emitting device according to one embodiment of the present invention. [Figure 39] A cross-sectional view illustrating a light-emitting device according to one embodiment of the present invention. [Figure 40] A diagram illustrating a lighting device and electronic equipment according to one embodiment of the present invention. [Figure 41] A diagram illustrating a lighting device according to one embodiment of the present invention. [Figure 42] A schematic cross-sectional view illustrating a light-emitting element according to an embodiment. [Figure 43] A diagram illustrating the brightness-current density characteristics of a light-emitting element according to an embodiment. [Figure 44] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 45] A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 46] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 47] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 48] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 49] A diagram illustrating the absorption spectrum and emission spectrum of a compound in an example. [Figure 50] A diagram illustrating the emission spectrum of a compound in an example. [Figure 51] A diagram illustrating the emission spectrum of a light-emitting element according to an embodiment. [Figure 52] A diagram illustrating the correlation between the external quantum efficiency and emission spectral intensity of a light-emitting element in an embodiment. [Figure 53]A diagram illustrating the reliability test results of the light-emitting element according to the embodiment. [Figure 54] A diagram illustrating the correlation between the weight ratio of impurities in a light-emitting element and its reliability in an example. [Figure 55] A diagram illustrating the brightness-current density characteristics of a light-emitting element according to an embodiment. [Figure 56] A diagram illustrating the brightness-voltage characteristics of a light-emitting element according to an embodiment. [Figure 57] A diagram illustrating the current efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 58] A diagram illustrating the external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 59] A diagram illustrating the power efficiency-luminance characteristics of a light-emitting element according to an embodiment. [Figure 60] A diagram illustrating the electroluminescence spectrum of a light-emitting element according to an embodiment. [Figure 61] A diagram illustrating the emission spectrum of a thin film according to the example. [Figure 62] A diagram illustrating the emission spectrum of a thin film according to the example. [Figure 63] A diagram illustrating the emission spectrum of a thin film according to the example. [Figure 64] A diagram illustrating the measurement results of the luminescence quantum yield of a thin film according to the example. [Figure 65] A diagram illustrating the measurement results of the luminescence quantum yield of a thin film according to the example. [Figure 66] A diagram illustrating the measurement results of the luminescence quantum yield of a thin film according to the example. [Figure 67] A diagram illustrating the transient fluorescence characteristics of a thin film according to an example. [Figure 68] A diagram illustrating the transient fluorescence characteristics of a thin film according to an example. [Figure 69] A diagram illustrating the transient fluorescence characteristics of a thin film according to an example. [Modes for carrying out the invention]

[0024] The embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is as follows The description is not limited to the present invention, and the form and details may not depart from the spirit and scope of the present invention. It is possible to change this in various ways. Therefore, the present invention can be described in the embodiments shown below. It is not interpreted as being limited to volume.

[0025] For the sake of ease of understanding, the position, size, and scope of each component shown in the drawings, etc., are as follows: The actual location, size, and range may not be represented. Therefore, the disclosed invention is It is not necessarily limited to the location, size, or scope disclosed in drawings, etc.

[0026] Furthermore, in this specification, the ordinal numbers used as "1st," "2nd," etc., are used for convenience. The order of processes or stacking may not be indicated. For example, "the first" may be written as "the second" or This can be replaced with "third," etc., as appropriate in the explanation. The ordinal numbers used and the ordinal numbers used to specify one aspect of the present invention may not be the same. be.

[0027] Furthermore, in this specification and other documents, when describing the structure of the invention using drawings, the same thing is used The symbols used may be consistent across different drawings.

[0028] Furthermore, in this specification, the terms "membrane" and "layer" are interchangeable. It is possible to change the term. For example, the term "conductive layer" can be changed to the term "conductive film." It may be possible to change it. Or, for example, change the term "insulating film" to "insulating layer". In some cases, it may be possible to change the terminology to this.

[0029] In this specification, etc., the singlet excited state (S * ) is a single with excitation energy It refers to a singlet state. Furthermore, the S1 level is the lowest singlet excitation energy level. It is the excitation energy level of the lowest singlet excited state (S1 state). Multiplet excited state (T * ) refers to a triplet state that has excitation energy. Also, T1 The level is the lowest level of triplet excitation energy levels, and is the lowest triplet excited state (T This refers to the excitation energy level of a state (1). In this specification, the term "singlet excitation" is used more specifically. Even when referred to as the initial state and the singlet excitation energy level, the S1 state and S1 It can also be expressed as a level. Furthermore, it is sometimes written as triplet excited state and triplet excited energy level. Even in such cases, it may still represent a T1 state and a T1 level.

[0030] Furthermore, in this specification, a fluorescent compound is defined as a compound that relaxes from a singlet excited state to a ground state. It is a substance that emits light in the visible light region when exposed to light. On the other hand, phosphorescent compounds are substances that exhibit triplet excited states. It is a substance that emits light in the visible light region at room temperature when it relaxes from its state to the ground state. In other words... Therefore, phosphorescent compounds are one type of substance that can convert triplet excitation energy into visible light. .

[0031] Furthermore, the phosphorescence emission energy or triplet excitation energy is the shortest wavelength side of the phosphorescence emission. It can be derived from the emission peak (including the shoulder) or the rising wavelength. Oh, this phosphorescence emission is time-resolved photoluminescence in a low-temperature environment (e.g., 10K). It can be observed by performing the spectroscopy method. Furthermore, the emission energy of thermally activated delayed fluorescence is , the shortest wavelength emission peak (including the shoulder) or rise time of thermally activated delayed fluorescence It can be derived from the wavelength.

[0032] In this specification, room temperature refers to any temperature between 0°C and 40°C.

[0033] Furthermore, in this specification, the blue wavelength region refers to waves between 400 nm and 500 nm. It is a long region, and blue emission means that there is at least one emission spectral peak in that region. It is light emission. Furthermore, the green wavelength range is the wavelength range between 500 nm and less than 580 nm. Green emission is defined as emission having at least one emission spectral peak in that region. Furthermore, the red wavelength range is the wavelength range between 580 nm and 680 nm, and the red wavelength range is Emission is defined as emission having at least one emission spectral peak in the region.

[0034] (Embodiment 1) In this embodiment, a light-emitting element according to one aspect of the present invention will be described below using Figures 1 to 5. I will reveal it.

[0035] <Example of light-emitting element configuration> First, regarding the configuration of a light-emitting element according to one aspect of the present invention, use Figures 1(A) and (B) to show the following: I will explain below.

[0036] Figure 1(A) is a schematic cross-sectional view of a light-emitting element 150 according to one embodiment of the present invention.

[0037] The light-emitting element 150 has a pair of electrodes (electrode 101 and electrode 102), and between the pair of electrodes It has an EL layer 100 provided therein. The EL layer 100 has at least an emissive layer 130. .

[0038] Furthermore, the EL layer 100 shown in Figure 1(A) includes, in addition to the light-emitting layer 130, a hole injection layer 111, and It has functional layers such as a pore transport layer 112, an electron transport layer 118, and an electron injection layer 119.

[0039] In this embodiment, of the pair of electrodes, electrode 101 is used as the anode, and electrode 1 Although 02 is described as the cathode, this is not the case for the configuration of the light-emitting element 150. Then, electrode 101 is used as the cathode and electrode 102 as the anode, and the stacking of each layer between these electrodes is done in the reverse order. It may also be arranged in this order. That is, from the anode side, a hole injection layer 111, a hole transport layer 112, and The order in which the optical layer 130, electron transport layer 118, and electron injection layer 119 are stacked should be as follows. .

[0040] Note that the configuration of the EL layer 100 is not limited to the configuration shown in Figure 1(A), and the hole injection layer 111 At least one of the hole transport layer 112, electron transport layer 118, and electron injection layer 119 selected It is sufficient to have a configuration that has one of either. Alternatively, the EL layer 100 can be a hole or electron injection To reduce barriers, improve hole or electron transport, or inhibit hole or electron transport. It has a functional layer that has functions such as being able to suppress the quenching phenomenon caused by electrodes. It may also be configured as follows. Note that even if each functional layer is a single layer, a configuration in which multiple layers are stacked may also be possible. It may be possible.

[0041] Figure 1(B) is a schematic cross-sectional view showing an example of the light-emitting layer 130 shown in Figure 1(A). The light-emitting layer 130 shown in B) comprises a host material 131 and a guest material 132.

[0042] The host material 131 only needs to contain at least an organic compound 131_1. Compound 131_1 is preferably a compound that has the function of transporting electrons (has electron transport properties). Preferably, the compound has a nitrogen-containing six-membered heteroaromatic skeleton. The grade is preferable because it has high electron transport properties and is stable.

[0043] Furthermore, it is preferable that the host material 131 also contains an organic compound 131_2. Compound 131_2 is preferably a compound that has the function of transporting holes (has hole transport properties). Preferably, the compound has a nitrogen-containing five-membered heterocyclic skeleton or a tertiary amine skeleton. A five-membered heterocyclic skeleton or a tertiary amine skeleton is preferred because it has high hole transport properties and is stable.

[0044] Furthermore, the combination of organic compound 131_1 and organic compound 131_2 exhibits electron transport properties. In the case of a combination of a compound that possesses hole transport properties and a compound that has hole transport properties, the mixing ratio of the two compounds will This makes it possible to easily control the carrier balance. Specifically, it has electron transport properties. Compounds: Compounds with hole transport properties = preferably in the range of 1:9 to 9:1 (weight ratio). Furthermore, having this configuration makes it easy to control the career balance. Furthermore, the carrier recombination region can be easily controlled.

[0045] Furthermore, as the guest material 132, a luminescent organic compound may be used, and the luminescent organic compound As for the compound, it is a substance that can emit fluorescence (hereinafter referred to as a fluorescent compound) or phosphorescent It is preferable that the substance is capable of emitting light (hereinafter also referred to as a phosphorescent compound). In the present invention, the guest material 132 is configured to use a fluorescent compound or a phosphorescent compound. This will be explained. Note that guest material 132 is read as a fluorescent compound or phosphorescent compound. You may substitute it.

[0046] In one embodiment of the present invention, the light-emitting element 150 comprises a pair of electrodes (electrode 101 and electrode 102 By applying a voltage between them, electrons are released from the cathode and holes from the anode. The electrons and holes are injected into the EL layer 100, and an electric current flows. Then, the injected electrons and holes recombine. This process forms an exciton. An exciton is a pair of carriers (electrons and holes). This is the case. Since excitons have excitation energy, the material on which excitons are formed becomes excited. This is the state it is in.

[0047] When carriers recombine in the host material 131, excitons are generated, which contributes to the host material An excited state (singlet excited state or triplet excited state) is formed in material 131. (Guest material) If 132 is a fluorescent compound, the S1 level of the host material 131 is converted to the S1 level of the guest material 132. The excitation energy is transferred to the energy level, forming a singlet excited state for guest material 132. Furthermore, if the guest material 132 is a phosphorescent compound, the S1 level of the host material 131 is also affected. Alternatively, the excitation energy is transferred from the T1 level to the T1 level of guest material 132. A triplet excited state is formed in guest material 132. And in either case, excitation occurs. Guest material 132 emits light when it deactivates to its ground state.

[0048] One of the characteristics required of the light-emitting element 150 is high luminous efficiency. It has little decrease in luminous efficiency due to storage or long-term operation, that is, it has a long lifespan. In other words, high reliability is required. Light-emitting elements have high luminous efficiency. In order to achieve high reliability, the EL layer 100, and especially the light-emitting layer 130, must contain impurities. It is preferable to use organic compounds in small quantities.

[0049] To obtain organic compounds with low impurity content, the purity of the organic compounds must be increased. This is preferable. For example, impurities such as solvents used when synthesizing organic compounds and solvents, etc. The impurities contained in the organic compounds and the elements in the raw materials used in the synthesis of the organic compounds are present. When a light-emitting element is fabricated using organic compounds, the characteristics of the light-emitting element, such as the driving voltage characteristics, may change. The properties, luminous efficiency characteristics, and reliability may deteriorate. Furthermore, for example, these impurities may also be a factor. Among substances, impurities containing halogen elements have a significant impact, so their content should be small. This is preferable. Therefore, the organic compounds used in the light-emitting element are purified by sublimation to remove impurities. Commonly used materials are purified by sublimation, which removes residual solvents from the synthesis and trace amounts of impurities (e.g., For example, it can be used to separate halides.

[0050] However, due to reasons such as the similarity in molecular structure to the organic compound used in the EL layer 100, Some impurities are difficult to reduce in quantity, and even materials that have undergone sublimation purification may still contain these impurities. In some cases, substances may be present. Also, in the organic compounds used to fabricate light-emitting elements... Even if the impurity content is reduced, impurities may be introduced during the fabrication of the light-emitting element, It may contain impurities. For example, during vacuum deposition, organic compounds may decompose. In some cases, the substances produced may be mixed into the light-emitting element as impurities. Also, for example, in coating methods... In manufacturing methods using solvents such as inkjet and printing methods, the solvent or the solvent Impurities may be mixed into the light-emitting element. Also, when driving the light-emitting element, organic compounds may be present. Substances generated by decomposition may be present in the light-emitting element as impurities. Therefore, it is difficult to eliminate all impurities present in the light-emitting element.

[0051] On the other hand, there are impurities that, even if present in the EL layer 100, do not affect the characteristics of the light-emitting element. However, even such impurities can interact with other compounds to produce light-emitting elements. The inventors have discovered that substances that affect the characteristics of the child may be generated. This includes organic compounds containing a nitrogen-containing five-membered heterocyclic skeleton or a secondary amine skeleton having an NH group, The interaction between an organic compound having a nitrogen-containing six-membered heteroaromatic skeleton and the light-emitting element results in the characteristics of the light-emitting element. Substances that affect the properties are generated. Therefore, organic compounds with a nitrogen-containing six-membered heteroaromatic skeleton are produced. In a light-emitting element containing a compound, the element has a nitrogen-containing five-membered heterocyclic skeleton with an NH group or a secondary amine. It is preferable that the content of organic compounds with a skeleton is low.

[0052] <Analysis of reaction mechanisms using quantum chemical calculations> ≪Calculation of the reaction mechanism between PCCH and 35DCzPPy≫ Here, organic compounds containing a nitrogen-containing five-membered heterocyclic skeleton or a secondary amine skeleton having an NH group. The interaction between the light-emitting element and an organic compound having a nitrogen-containing six-membered heteroaromatic skeleton results in the light-emitting element The process by which impurities that affect the properties are generated is explained below.

[0053] Quantum chemical calculations were used to analyze the above process. The structures and abbreviations of the compounds used in the calculations are listed below. The following is shown.

[0054] [ka]

[0055] The calculation shows that 3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol PCCH (abbreviation) and 3,5-bis[3-(9H-carbazole-9-yl)phenyl The interaction with pyridine (abbreviation: 35DCzPPy) causes the NH group of PCCH to The incoming hydrogen atom moves to 35DCzPPy, and the above structure PCC and 35DCzPPy- We analyzed the hydrogen atom transfer reaction that produces H.

[0056] The calculation method is as follows. Note that the quantum chemistry calculation program used is Ga I used ussian09. The calculations were performed on a high-performance computer (manufactured by SGI). This was performed using ICE X.

[0057] Initial state, transition state, and final state of a hydrogen atom transfer reaction in the lowest triplet excited state. The stable structure of the state was calculated using density functional theory (DFT). Furthermore, the most stable structure of each state was calculated. Vibration analysis was performed in the construction. The total energy of the DFT is the potential energy. Exchange encompasses electrostatic energy between electrons, kinetic energy of electrons, and complex interactions between electrons. It is expressed as the sum of correlation energies. In DFT, the one-electron potential is expressed in terms of electron density. The calculation is fast because it approximates the exchange-correlation interaction with a functional (meaning a function of a function). Here, using the mixed functional B3LYP, we examine each parameter related to exchange and correlation energy. The meter weights were defined. Additionally, 6-311G(d,p) was used as the basis function.

[0058] Analysis of the hydrogen atom transfer reaction in the triplet lowest excited state revealed the reaction pathway and energy The diagram is shown in Figure 2.

[0059] In Figure 2, PCCH in the T1 state and 35DCzPPy in the ground state (S0 state) are not The energy of the state at its limit of dissociation was used as the reference. The activation energy of the reaction in which this hydrogen atom moves The energy is very small, at 0.03 eV, and can easily occur at room temperature. Furthermore, hydrogen atoms In the final state after transfer, PCC and 35DCzPPy-H are both in a radical state. Furthermore, the energy of the final state is lower than the energy of the initial state, and this reaction is exothermic. From this, it can be seen that in the light-emitting layer (excited state) when the light-emitting element is driven, PCCH If 35DCzPPy is in a molecular configuration that forms a hydrogen bond, then the transfer of hydrogen atoms Dynamic reactions may occur rapidly. Furthermore, from the excited state of organic compounds containing an NH group... If the activation energy required for the NH bond to dissociate is 0.3 eV or less, then at room temperature... Hydrogen dissociates easily in this environment.

[0060] At this time, the final states are the radical state PCC and the radical state 35DCzPPy-H It has a higher energy than PCCH in the S0 state and 35DCzPPy in the S0 state. Therefore, if there are no side reactions, the generated radical state PCC and the radical state 35DCzPPy-H can be reversibly converted back to the original S0 state PCCH and S0 state 35DCzP It can be returned to Py by thermal deactivation.

[0061] This reaction is considered in a light-emitting device containing a guest material. Final state (radical state P) The energy levels of CC and the radical state (35DCzPPy-H) are excited by the guest material. If the excitation energy level is lower than the state, guests from PCC and 35DCzPPy-H Energy transfer to the material becomes impossible. Also, in this case, the final state (radical state) The PCC and radical states (35DCzPPy-H) and the excited state of the guest material are simultaneously generated. As a result, the excited state guest material gives rise to the radical state PCC and the radical state 35DC. This causes an energy transfer to zPPy-H, resulting in emission from the guest material. Because this is no longer obtained, the luminous efficiency of the light-emitting element decreases.

[0062] Next, the reactants (PCCH and 35DCzPPy) and product (P) of the above hydrogen atom transfer reaction. Ionization potential (Ip) and electron affinity (Ea) of CC and 35DCzPPy-H The following was calculated. Here, the ionization potentials of PCCH and 35DCzPPy are radical The electron affinity is calculated from the difference in total energy between the thione state and the singlet ground state, and is the same as the singlet ground state. It was calculated from the difference in total energy between the state and the radical anion state. PCC and 35DCzPPy -The ionization potential of H is calculated from the difference in total energy between the cation state and the radical state. Furthermore, electron affinity was calculated from the difference in total energy between the radical state and the anionic state. This state assumes the driving state of the light-emitting element, that is, the state in which carriers have been injected into the molecules. It's a calculation.

[0063] The ionization potential (IP) and electron affinity (E) of each compound, estimated as described above, are as follows: a) is shown in Table 1.

[0064] [Table 1]

[0065] The smaller the ionization potential, the easier it is for holes to enter the molecule, and the electron affinity... The larger the value, the easier it is for electrons to enter the molecule. In other words, a hole is 35DCzPPy -H is the easiest to enter, and electrons are most easily entered into PCCs.

[0066] Next, the PCC in the radical state accepts an electron and becomes an anion state, and the radical state When the 35DCzPPy-H in state accepts a hole and becomes a cation, the T1 level is The energy was calculated. The energy of the T1 level for each compound is shown in Table 2. Here, the T1 level The energy of is the total energy of the triplet lowest excited state (T1 state) and the singlet ground state (S0 state). It was calculated from the difference in energy levels.

[0067] [Table 2]

[0068] As shown in Table 2, in the anionic state PCC and the cationic state 35DCzPPy-H All of the T1 levels were low energy levels, below 2 eV. Therefore, these A phosphorescent compound having a T1 level higher than at least one of the T1 levels is used as a guest material. In the light-emitting element having the host material 131 and the guest material 132, the triplet excitation The electromotive force is transferred to the anionic state PCC or the cationic state 35DCzPPy-H. As a result, the excitation energy of the host material 131 and the guest material 132 is deactivated. It's cheap.

[0069] As described above, in the coexistence of PCCH and 35DCzPPy, in the excited state, PCCH The hydrogen atom originating from the NH group moves to 35DCzPPy. In this case, the excitation energy of the host material 131 is deactivated without being transferred to the guest material 132. It is easy to lose it. Also, compounds (PCC and 35D) that are temporarily produced by hydrogen transfer reactions. The T1 level in the charged states (cationic and anionic states) of CzPPy-H is energy Because it is at an energy-low level, the T1 level is used as the phosphorescent guest material 132. There is a high probability that the resulting compound will be lower than the T1 level of the compound, and the resulting compound will be light-emitting element 15 It can act as a quenching factor of 0. Furthermore, these generated PCC and 35DCzPPy-H can be recycled. Irreversible reactions involving repeated excitation, oxidation, and reduction lead to even lower energy levels. It may react further to objects that have a position. Therefore, the drive of the light-emitting element 150 Hydrogen transfer reactions that proceed under motion can lead to a decrease in reliability. Therefore, luminescence If layer 130 contains 35DCzPPy, the PCCH content in the light-emitting layer 130 is small. It is preferable.

[0070] Note that in the above calculation, PCCH in state T1 and 35D in the ground state (S0 state) are used. We performed a calculation using CzPPy as the initial state, but the initial state was PCC in state S1. H and the ground state (S0 state) 35DCzPPy may also be used. The S1 state is the T1 state. Because they are higher energy excited states, PCCH is in the S1 state and 35DC is in the S0 state. When zPPy reacts with PCCH, the initial energy becomes higher, and The reaction between this and 35DCzPPy is more likely to occur. Therefore, even in this case, the PC The reaction between CH and 35DCzPPy causes the excitation energy of the host material 131 to be... In some cases, the hydrogen may become inactive without moving to material 132. Also, due to the hydrogen transfer reaction... S1 level in the charged states (cationic and anionic states) of temporarily formed compounds Since this results in a low energy level, the S1 level is used as the fluorescent material 132. If the level is lower than the S1 level of the compound, the generated compound becomes a quenching factor for the light-emitting element 150. This is possible. In this case as well, the generated PCC and 35DCzPPy-H can be subjected to repeated excitation and oxidation. , and through irreversible reactions associated with reduction, further reducing to those with even lower energy levels. A reaction may occur. Therefore, hydrogen transfer proceeds due to the driving of the light-emitting element 150. The reaction may cause a decrease in reliability. Therefore, a fluorescent compound is added to guest material 132. Even when using materials, if the light-emitting layer 130 contains 35DCzPPy, the light-emitting layer 1 A low PCCH content in 30 is preferable.

[0071] ≪Calculation of reactivity based on the state of PCCH≫ Next, when the initial state PCCH is not in an excited state, the origin of the NH group of PCCH We calculated the stabilization energy when a hydrogen atom dissociates. The calculation involved P in various states. Starting with CCH and 35DCzPPy, the hydrogen atoms originating from the NH group of PCCH are infinite. The final state is when it dissociates into 35DCzPPy and binds to it, and the energy difference between them is stabilized. The calculation was performed using energy. The calculation method should be based on the method described above. The calculation results are shown in Table 3. This will be shown.

[0072] [Table 3]

[0073] As shown in Table 3, 35DCzPPy is the ground state (S0 state), and PCCH is the ground state. In the case of a state (S0 state) or a radical cation state, the energy difference between the initial state and the final state Because the stabilization energy is greater than 1 eV, the hydrogen atom originating from the NH group of PCCH The dissociation reaction is less likely to occur. On the other hand, when PCCH is in an excited state (T1 state) or 35DCz When PPy is in a radical anion state, the stabilization is the energy difference between the initial state and the final state. Because the energy is less than 1 eV, the hydrogen atom originating from the NH group of PCCH dissociates. A response is likely to occur, and in particular, when PCCH is in an excited state (T1 state), the stabilization energy is Since the voltage is less than 0 eV, it can be seen that the reaction is likely to occur. Note that the S1 state is higher than the T1 state. Because it has a high excitation energy, the reaction is likely to occur even when PCCH is in the S1 state. ru.

[0074] Next, when PCCH exists alone, the hydrogen atom derived from the NH group of PCCH dissociates. We performed a similar calculation to see if it was possible. The calculation results are shown in Table 4.

[0075] [Table 4]

[0076] As shown in Table 4, when PCCH exists alone, the NH group of PCCH is the origin. The final state is defined as the case where the hydrogen atoms dissociate to infinity, and the relationship between each initial state and the final state of PCCH The energy difference was calculated as the stabilization energy. In this case, the initial state of PCCH is state T1. Except in the case of PCCH, the stabilizing energy when the hydrogen atom derived from the NH group dissociates The gee is greater than 1 eV. Therefore, the initial state is a state other than the excited state (S0 state, radical). In the anionic state and radical cation state, the hydrogen atom originating from the NH group of PCCH is dissolved. It can be seen that the release reaction is unlikely to occur. Also, if the initial state is state T1, the stabilizing energy Although Ghee is less than 1 eV, its stabilization energy is lower than when it coexists with 35 DCz PPy. Because of its large size, it is suggested that reactions involving the dissociation of hydrogen atoms are unlikely to occur.

[0077] In other words, the reaction in which a hydrogen atom derived from the NH group of PCCH dissociates is 35DCPPy This reaction is particularly likely to occur when PCCH is present.

[0078] Calculations for compounds that can react with PCCH Next, by coexisting with PCCH in the light-emitting layer, the water in the NH group of the PCCH To investigate the molecular structure of organic compounds in which reactions involving the dissociation of elementary atoms can occur, calculations were performed. The structures and abbreviations of the compounds used in the calculations are listed below.

[0079] [ka]

[0080] The calculation method is the same as that used for calculating the reaction mechanism between PCCH and 35DCzPPy. PCCH in state 1 and 2,4,6-tris[3-(9H-carba] ​​in the ground state (S0 state). Hydrogen atom in zole-9-yl)phenyl]pyrimidine (abbreviation: mCzP3Pm) Figure 3(A) shows the reaction pathway and energy diagram obtained from the analysis of the transfer reaction, and the T1 state. PCCH and the ground state (S0 state) 4,6-bis[3-(9H-carbazole-9- Hydrogen atom transfer reaction between yl(phenyl)pyrimidine (abbreviation: 4,6mCzP2Pm) and Figure 3(B) shows the reaction pathway and energy diagram obtained from the analysis of the response, and the PC in state T1. CH and the ground state (S0 state) 2,6-bis[3-(9H-carbazole-9-yl) Solution for the hydrogen atom transfer reaction between phenyl]pyrazine (abbreviation: 2,6mCzP2Pr) and Figure 4(A) shows the reaction pathway and energy diagram obtained by analysis, with PCCH in the T1 state and , the ground state (S0 state) 2,4-bis[3-(9H-carbazole-9-yl)phen Hydrogen atom transfer reaction with [L]-1,3,5-triamidine (abbreviation: mCzP2Tzn) The reaction pathway and energy diagram obtained from the analysis of the response are shown in Fig. 4(B), respectively.

[0081] In Fig. 3(A), the energy of the dissociated state at infinite distance was used as a reference for the PCCH in the T1 state and mCzP3Pm in the ground state (S0 state). The activation energy of the reaction in which the hydrogen atom moves in this system is as low as 0.01 eV and can easily occur at room temperature. Furthermore, in the final state after the hydrogen atom transfer, PCC and mCzP3Pm-H are in a radical state, and the energy of the final state is lower than that of the initial state, so this reaction is an exothermic reaction. Therefore, when PCC H and mCzP3Pm are in a molecular arrangement that forms a hydrogen bond in the light-emitting layer (excited state) when the light-emitting device is driven, there is a possibility that a hydrogen atom transfer reaction will occur. From this, when PCC H and mCzP3Pm are in a molecular arrangement that forms a hydrogen bond in the light-emitting layer (excited state) when the light-emitting device is driven, there is a possibility that a hydrogen atom transfer reaction will occur.

[0082] Also, in the case of PCCH in the T1 state and 4,6mCzP2Pm, 2,6 mCzP2Pr, and mCzP2Tzn in the ground state (S0 state), there is no barrier due to activation energy for the reaction in which the hydrogen atom based on the NH group of PCCH moves. When PCCH and these organic compounds are in a molecular arrangement that forms a hydrogen bond, the hydrogen atom transfer reaction occurs rapidly. Therefore, in Figs. 3(B), 4(A), and 4(B), the energy of the state where PCCH in the T1 state and 4,6mCzP2Pm, 2,6mCzP2Pr, and mCzP 2Tzn in the ground state (S0 state) do not interact is used as a reference. Also, in the final state after the hydrogen atom transfer, PCC and 4,6mCzP2Pm-H, 2,6mCzP2Pr-H, and mC zP2Tzn-H are in a radical state, and the energy of the final state is the energy of the initial state. zP2Tzn-H are in a radical state, and the energy of the final state is the energy of the initial state. -These reactions are lower than - and are exothermic. Therefore, when the light-emitting element is driven... In the luminescent layer in the excited state, PCCH and 4,6mCzP2Pm, 2,6mCz When P2Pr and mCzP2Tzn are in a molecular configuration that forms hydrogen bonds, The hydrogen atom transfer reaction may occur rapidly.

[0083] Next, when coexisting with PCCH, the hydrogen atoms derived from the NH group of PCCH dissociate. Calculations were performed to investigate the molecular structures of organic compounds that are prone to reactions. The structures and abbreviations of the organic compounds are listed below. Note that the structures and abbreviations of other compounds are listed above. You should take that into consideration.

[0084] [ka]

[0085] [ka]

[0086] The calculation involves PCCH (molecule 1) in the T1 state and various organic compounds in the ground state (S0 state). Starting with molecule 2), PCC is formed when the hydrogen atoms derived from the NH group of PCCH are dissociated, and the water The final state is defined as the state in which elementary atoms bond to an organic compound (molecule 2) at infinity and become stable, and its energy The energy difference was calculated as the stabilization energy. The calculation results are shown in Tables 5 and 6. 6 contains the LUMO (Lowest Unoccupied Molecular Weight) of molecule 2. The results of the calculation of the Orbital (also known as the lowest-level orbital) are also shown.

[0087] [Table 5]

[0088]

Table 6

[0089] As shown in Table 5, when 4,4’,4’ ’-tris(carbazol-9-yl)triphenylamine (abbreviation: TCTA) and 1, 3-bis(N-carbazolyl)benzene (abbreviation: mCP) coexist, the stabilization energy when the hydrogen atom in the NH group of P CCH dissociates is greater than 1 eV, indicating that the reaction is unlikely to occur.

[0090] On the other hand, as shown in Table 6, when 1,3,5 -tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB), 35DCz PPy, 5,5’-bis[3-(9H-carbazol-9-yl)phenyl]-3,3’ -bipyridine (abbreviation: 5,5’mCzP2BPy(3)), 4,4’-bis[3-(9H -carbazol-9-yl)phenyl]-2,2’-bipyridine (abbreviation: 4,4’mCz P2BPy), 4,6mCzP2Pm, and mCzP3Pm coexist, the stabilization energy when the hydrogen atom in the NH group of PCCH dissociates is less than 0 eV and it is an exothermic reaction, indicating that the reaction is likely to occur.

[0091] Next, the correlation between the LUMO level (calculated value) of the organic compound having the nitrogen-containing six-membered heteroaromatic skeleton and the stabilization energy (energy difference between the initial state and the final state) when the hydrogen atom derived from the NH group of PCCH dissociates is shown in Fig. 5.

[0092] As shown in Figure 5, the lower the LUMO level of the organic compound (molecule 2), the lower the PCCH level. The stabilization energy when the hydrogen atom derived from the NH group dissociates becomes smaller, and the hydrogen atom becomes P This resulted in increased dissociation from CCH.

[0093] As described above, when PCCH is present, a reaction in which the hydrogen atom of the NH group dissociates is likely to occur. The compound is not limited to 35DCzPPy, but also includes organic compounds having a nitrogen-containing six-membered heteroaromatic skeleton. Any object will do.

[0094] Furthermore, the dissociation energy at which a hydrogen atom dissociates from the NH group is affected by changes in the molecular structure other than the NH group. Even if this is done, there is almost no change. Therefore, as mentioned above, the hydrogen atom derived from the NH group dissociates. The organic compounds that readily undergo this reaction are not limited to PCCH. As shown above, a nitrogen-containing five-membered heterocyclic skeleton or a secondary amine skeleton or primary amine skeleton having an NH group This reaction occurs similarly in organic compounds containing [the specified compound].

[0095] It has a nitrogen-containing five-membered heterocyclic skeleton, a secondary amine skeleton, or a primary amine skeleton with an NH group. Examples of organic compounds include pyrrole skeletons having NH groups, imidazole skeletons, and tori Organics having an azole skeleton, a tetrazole skeleton, or an aromatic amine skeleton having an NH group Examples of compounds include the indole skeleton and the pyrrole skeleton having an NH group. Examples include carbazole skeletons. Also, secondary amine skeletons and primary amine skeletons having an NH group. Examples of ammonium skeletons include diarylamine skeletons and monoarylamine skeletons. It can be done.

[0096] Therefore, the light-emitting layer of the light-emitting element contains an organic compound having a nitrogen-containing six-membered heteroaromatic skeleton. In some cases, a nitrogen-containing five-membered heterocyclic skeleton having an NH group like PCCH, a secondary amine skeleton, or It is preferable that the content of organic compounds having a primary amine skeleton be low.

[0097] Specifically, when organic compound 131_1 has a nitrogen-containing six-membered heteroaromatic skeleton, luminescence occurs. In layer 130, a nitrogen-containing five-membered heterocyclic skeleton having an NH group, a secondary amine skeleton, or a primary amine skeleton. The content of organic compounds containing an amine skeleton is preferred in weight ratio to organic compound 131_1. The value should be 0.03 or less, more preferably 0.003 or less. Therefore, the NH group Organic compounds containing a nitrogen-containing five-membered heterocyclic skeleton, a secondary amine skeleton, or a primary amine skeleton. The nitrogen reacts with organic compound 131_1 having a nitrogen-containing six-membered heteroaromatic skeleton to produce a nitrogen Nitrogen-containing five-membered heterocyclic skeleton, secondary amine skeleton, or primary amine skeleton with elementary atoms having unpaired electrons The content of organic compounds including the specified compound is preferably 0 by weight relative to organic compound 131_1. The molecular weight is 0.03 or less, more preferably 0.003 or less, and has a nitrogen-containing six-membered heteroaromatic skeleton. The amount of organic compounds in which an additional hydrogen atom is bonded to organic compound 131_1 is: Preferably, the weight ratio to 31_1 is 0.03 or less, and more preferably 0.003 or less. be.

[0098] In addition to calculations based on weight ratio, impurities are separated using a column, and the long-wavelength absorption spectrum is then measured. The relative abundance can also be estimated from the ratio of peaks that appear on the longer side.

[0099] Furthermore, organic compound 131_1 has a nitrogen-containing six-membered heteroaromatic skeleton, and organic compound 131 When _2 has at least one of a nitrogen-containing five-membered heterocyclic skeleton or a tertiary amine skeleton, luminescence In layer 130, a nitrogen-containing five-membered heterocyclic skeleton having an NH group, a secondary amine skeleton, or a primary amine skeleton. The content of organic compounds containing an amine skeleton is preferred in weight ratio to organic compound 131_2. The value should be 0.01 or less, more preferably 0.001 or less. Therefore, the NH group Organic compounds containing a nitrogen-containing five-membered heterocyclic skeleton, a secondary amine skeleton, or a primary amine skeleton. The nitrogen reacts with organic compound 131_1 having a nitrogen-containing six-membered heteroaromatic skeleton to produce a nitrogen Nitrogen-containing five-membered heterocyclic skeleton, secondary amine skeleton, or primary amine skeleton with elementary atoms having unpaired electrons The content of organic compounds including the specified compound is preferably 0 by weight relative to organic compound 131_2. The molecular weight is 0.01 or less, more preferably 0.001 or less, and has a nitrogen-containing six-membered heteroaromatic skeleton. The amount of organic compounds in which an additional hydrogen atom is bonded to organic compound 131_1 is: Preferably, the weight ratio to 31_2 is 0.01 or less, and more preferably 0.001 or less. be.

[0100] <Material> Next, the details of the components of the light-emitting element according to one aspect of the present invention will be described below.

[0101] ≪Luminous layer≫ In the light-emitting layer 130, the host material 131 is the most abundant by weight, followed by the guest material 132 It is dispersed in the host material 131. If the guest material 132 is a fluorescent compound, the luminescent layer S1 conditioned of host material 131 (organic compound 131_1 and organic compound 131_2) 130 The level is preferably higher than the S1 level of the guest material (guest material 132) of the emissive layer 130. Also, if the guest material 132 is a phosphorescent compound, the host material 131 of the light-emitting layer 130 The T1 level of (organic compound 131_1 and organic compound 131_2) is the ges of the light-emitting layer 130. It is preferable that the T1 level is higher than that of the guest material (guest material 132).

[0102] Organic compound 131_1 is preferably a compound having a nitrogen-containing six-membered heteroaromatic skeleton. It seems so. Specifically, pyridine skeleton, diazine skeleton (pyrazine skeleton, pyrimidine skeleton, and Examples include compounds having a pyridazine skeleton and a triazine skeleton. These basic Examples of compounds having a nitrogen-containing heteroaromatic skeleton include pyridine derivatives and bipyramidal compounds. Lysine derivatives, pyrimidine derivatives, triazine derivatives, quinoxaline derivatives, dibenzox Examples of compounds include noxaline derivatives, phenanthroline derivatives, and purine derivatives. Furthermore, as organic compound 131_1, it is a material that has higher electron transport properties than holes (electron transport properties) (Materials) can be used, 1 × 10 -6 cm 2 Materials having an electron mobility of / Vs or greater It is preferable to have one.

[0103] Specifically, for example, vasophenanthroline (abbreviation: BPhen), vasocuproin (Abbreviation: BCP) and other heterocyclic compounds having a pyridine skeleton, and 2-[3-(dibenzothi Offen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTP) DBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl ]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3' -(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoki Sarin (abbreviation: 2mCzBPDBq), 2-[4-(3,6-diphenyl-9H-carb Zole-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2CzPDBq) -III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h ]Quinoxaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(dibenzothio Fen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPD) Bq-II), 2-[3-(3,9'-bi-9H-carbazole-9-yl)phenyl] Dibenzo[f,h]quinoxaline (abbreviation: 2mCzCzPDBq), 4,6-bis[3- (Phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-Bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mD) BTP2Pm-II), 4,6-bis[3-(9H-carbazole-9-yl)phenyl Heterocyclic compounds having a diazine skeleton, such as pyrimidines (abbreviation: 4,6mCzP2Pm) Or, 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carb Zole-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: Heterocyclic compounds having a triazine skeleton such as PCCzPTzn, and 3,5-bis[3- (9H-carbazole-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1 ,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB), etc. Heterocyclic compounds having a pyridine skeleton can also be used. Among the heterocyclic compounds mentioned above, However, triazine skeleton, diazine (pyrimidine, pyrazine, pyridazine) skeleton, or pi Heterocyclic compounds having a lysine skeleton are stable, reliable, and therefore preferred. Heterocyclic compounds with a specific property exhibit high electron transport properties and contribute to reducing the driving voltage. (2,5-pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene) (-2,7-diyl)-co-(pyridine-3,5-diyl) (abbreviation: PF-Py), Ri[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridyl) It is also possible to use polymer compounds such as n-6,6'-diyl) (abbreviation: PF-BPy). Yes, it is possible. The substances mentioned here are mainly 1 × 10 -6 cm 2 Having an electron mobility of / Vs or greater It is a substance. Furthermore, any substance with higher electron transport capabilities than holes can be used. That's fine.

[0104] Organic compound 131_2 has a nitrogen-containing five-membered heterocyclic skeleton or a tertiary amine skeleton. Compounds are preferred. Specifically, compounds having a pyrrole skeleton or an aromatic amine skeleton are preferred. Examples include indole derivatives, carbazole derivatives, and triarylamine derivatives. Examples include the body. Furthermore, nitrogen-containing five-membered heterocyclic skeletons include the imidazole skeleton and tria. Examples include the zole skeleton and the tetrazole skeleton. Furthermore, as for organic compound 131_2... This allows the use of materials with higher hole transport capabilities than electron transport (hole transport materials), resulting in a capacity of 1 × 10⁻⁶. -6 cm 2 It is preferable that the material has a hole mobility of / Vs or greater. The material used for feeding may be a polymer compound.

[0105] Specifically, as materials with high hole transport properties, aromatic amine compounds include N, N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DT) DPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenyl Mino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3-methylphenyl [amino]phenyl]-N,N'-diphenyl-(1,1'-biphenyl)-4,4' -Diamine (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylaminophen) Examples include [phenyl]-N-phenylaminobenzene (abbreviation: DPA3B), etc. .

[0106] Furthermore, as a carbazole derivative, specifically, 3-[N-(4-diphenylamino Phenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1) ), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9 -Phenylcarbazole (abbreviation: PCzDPA2), 3,6-bis[N-(4-diphenyl (Aminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation) :PCzTPN2), 3-[N-(9-phenylcarbazole-3-yl)-N-phenyl Luamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N- (9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarb Zol (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcate Luvazole-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1) Examples include:

[0107] In addition, other carbazole derivatives include 4,4'-di(N-carbazolyl)bife Nyl (abbreviated as CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]bene Zen (abbreviation: TCPB), 9-[4-(10-phenyl-9-antryl)phenyl]- 9H-carbazole (abbreviation: CzPA), 1,4-bis[4-(N-carbazolyl)phen [Nyl]-2,3,5,6-tetraphenylbenzene, etc., can be used.

[0108] Also, N,N-diphenyl-9-[4-(10-phenyl-9-antryl)phenyl ]-9H-carbazole-3-amine (abbreviation: CzA1PA), 4-(10-phenyl- 9-Anthryl)triphenylamine (abbreviation: DPhPA), 4-(9H-carbazole) -9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), N,9-diphenyl-N-[4-(10-phenyl-9-antryl)f [phenyl]-9H-carbazole-3-amine (abbreviation: PCAPA), N,9-diphenyl -N-{4-[4-(10-phenyl-9-antryl)phenyl]phenyl}-9H- Carbazole-3-amine (abbreviation: PCAPBA), N,9-diphenyl-N-(9,1 0-Diphenyl-2-anthryl)-9H-carbazole-3-amine (abbreviation: 2PCA) PA), 9-phenyl-3-[4-(10-phenyl-9-antryl)phenyl]-9 H-carbazole (abbreviation: PCzPA), 3,6-diphenyl-9-[4-(10-phenyl Nyl-9-antryl)phenyl]-9H-carbazole (abbreviation: DPCzPA), N, N,N',N',N'',N'',N''',N'''-Octaphenyldibenzo[g, Using p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), etc. can.

[0109] Also, poly(N-vinylcarbazole) (abbreviation: PVK) and poly(4-vinyltriphen Nylamine (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenyl [amino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide]( Abbreviation: PTPDMA), poly[N,N'-bis(4-butylphenyl)-N,N'-bis High molecular weight compounds such as (phenyl)benzidine (abbreviated as Poly-TPD) can also be used. can.

[0110] Furthermore, as a material with high hole transport properties, for example, 4,4'-bis[N-(1-naphthium [N-phenylamino]biphenyl (abbreviated as NPB or α-NPD) or N,N'- Bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4, 4'-Diamine (abbreviation: TPD), 4,4',4''-Tris(carbazole-9-yl) ) Triphenylamine (abbreviation: TCTA), 4,4',4''-tris[N-(1-naphtholamine) [1'-TNATA]-N-phenylaminotriphenylamine (abbreviation: 1'-TNATA), 4,4 ',4''-Tris(N,N-diphenylamino)triphenylamine (abbreviation: TDAT) A) 4,4',4''-Tris[N-(3-methylphenyl)-N-phenylamino] Triphenylamine (abbreviation: MTDATA), 4,4'-bis[N-(spiro-9,9' -bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), 4 -phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)trife Nylamine (abbreviation: mBPAFLP), N-(9,9-dimethyl-9H-fluorene-2) -yl)-N-{9,9-dimethyl-2-[N'-phenyl-N'-(9,9-dimethyl -9H-fluoren-2-yl)amino]-9H-fluoren-7-yl}phenylamine N (abbreviation: DFLADFL), N-(9,9-dimethyl-2-diphenylamino-9H- Fluoren-7-yl)diphenylamine (abbreviation: DPNF), 2-[N-(4-diphenyl [Nylaminophenyl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: DPASF), 4-phenyl-4'-(9-phenyl-9H-carbazole-3-yl) Triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9- Phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBBi1B) P), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazole-3-yl) Triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''- (9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBN) BB), 4-phenyldiphenyl-(9-phenyl-9H-carbazole-3-yl) Min (abbreviation: PCA1BP), N,N'-bis(9-phenylcarbazole-3-yl) -N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N,N', N''-triphenyl-N,N',N''-tris(9-phenylcarbazole-3-I) (L)Benzene-1,3,5-triamine (abbreviation: PCA3B), N-(4-biphenyl) -N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-cal Bazole-3-amine (abbreviation: PCBiF), N-(1,1'-biphenyl-4-yl) -N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-di Methyl-9H-fluoren-2-amine (abbreviation: PCBBiF), 9,9-dimethyl-N -phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl] Luoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl -9H-carbazole-3-yl)phenyl]spiro-9,9'-bifluoren-2-a Min (abbreviation: PCBASF), 2-[N-(9-phenylcarbazole-3-yl)-N -phenylamino]spiro-9,9'-bifluorene (abbreviation: PCASF), 2,7-bi S[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'- Bifluoren (abbreviation: DPA2SF), N-[4-(9H-carbazole-9-yl) [phenyl]-N-(4-phenyl)phenylaniline (abbreviation: YGA1BP), N,N'- Bis[4-(carbazole-9-yl)phenyl]-N,N'-diphenyl-9,9-di Aromatic amine compounds such as methylfluorene-2,7-diamine (abbreviation: YGA2F), etc. It can also be used. Furthermore, 3-[4-(1-naphthyl)-phenyl]-9-phenyl -9H-carbazole (abbreviation: PCPN), 3-[4-(9-phenanthril)-pheni [Lu]-9-phenyl-9H-carbazole (abbreviation: PCPPn), 3,3'-bis(9- Phenyl-9H-carbazole (abbreviation: PCCP), 1,3-bis(N-carbazolyl) )Benzene (abbreviation: mCP), 3,6-bis(3,5-diphenylphenyl)-9-phenyl Nilcarbazole (abbreviation: CzTP), 3,6-di(9H-carbazole-9-yl)- 9-phenyl-9H-carbazole (abbreviation: PhCzGI), 2,8-di(9H-carbazole) Amine compounds such as zole-9-yl)-dibenzothiophene (abbreviation: Cz2DBT), Luvazole compounds and the like can be used. Among the compounds mentioned above, pyrrole skeleton, aromatic Compounds having a fragrance amine skeleton are stable, reliable, and therefore preferable. Compounds possessing this property exhibit high hole transportability and contribute to reducing the driving voltage.

[0111] Furthermore, as organic compound 131_2, the imidazole skeleton, the triazole skeleton, and the Compounds having a nitrogen-containing five-membered heterocyclic skeleton, such as a trazole skeleton, can be used. For example, 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butyl Phenyl)-1,2,4-triazole (abbreviation: TAZ), 9-[4-(4,5-diphenyl Nyl-4H-1,2,4-triazole-3-yl)phenyl]-9H-carbazole( Abbreviation: CzTAZ1), 2,2',2''-(1,3,5-benzenetriyl)tris( 1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzo Thiofen-4-yl)phenyl]-1-phenyl-1H-benzoimidazole (abbreviation: mDBTBIm-II) and other similar technologies can be used.

[0112] Includes a nitrogen-containing five-membered heterocyclic skeleton, a secondary amine skeleton, or a primary amine skeleton having an NH group. Specifically, as an organic compound, for example, it has an NH group and is an organic compound 131_2 Examples include compounds having a part of the skeleton of the above-mentioned pyrrole skeleton. imidazole skeleton, triazole skeleton, tetrazole skeleton, triarylamine skeleton, etc. From the compounds that can be used as organic compound 131_2 having a nitrogen-containing five-membered heterocycle, Among the aryl groups or alkyl groups bonded to nitrogen in the skeleton or tertiary amine skeleton, a small number Examples include compounds having a structure in which at least one atom is substituted with hydrogen.

[0113] Furthermore, in the light-emitting layer 130, there are no particular limitations on the guest material 132, but fluorescence Examples of compounds include anthracene derivatives, tetracene derivatives, chrysene derivatives, and phenanthochemicals. Pyrene derivatives, pyrene derivatives, perylene derivatives, stilbene derivatives, acridone derivatives, Marine derivatives, phenoxazine derivatives, phenothiazine derivatives, etc. are preferred, for example: The following substances can be used.

[0114] Specifically, 5,6-bis[4-(10-phenyl-9-antryl)phenyl]-2 ,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl -9-anthryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2) BPy), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluorine) [Len-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: 1,6mMem FLPAPrn), N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl) )phenyl]-N,N'-bis(4-tert-butylphenyl)pyrene-1,6-dia Min (abbreviation: 1,6tBu-FLPAPrn), N,N'-diphenyl-N,N'-bis [4-(9-phenyl-9H-fluoren-9-yl)phenyl]-3,8-dicyclophenyl Xylpyrene-1,6-diamine (abbreviation: ch-1,6FLPAPrn), N,N'-bi Su[4-(9H-carbazole-9-yl)phenyl]-N,N'-diphenylstilbe n-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazole-9-yl) -4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA) , 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-ant) Lyl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4- (10-phenyl-9-anthryl)phenyl]-9H-carbazole-3-amine (abbreviated) Name: PCAPA), Perylene, 2,5,8,11-Tetra(tert-butyl)perylene (Abbreviation: TBP), 4-(10-phenyl-9-antryl)-4'-(9-phenyl- 9H-carbazole-3-yl)triphenylamine (abbreviation: PCBAPA), N,N' '-(2-tert-butylanthracene-9,10-diyldi-4,1-phenylene) Bis[N,N',N'-triphenyl-1,4-phenylenediamine] (abbreviation: DPAB) PA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl) [enyl]-9H-carbazole-3-amine (abbreviation: 2PCAPPA), N-[4-(9 ,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1 ,4-phenylenediamine (abbreviation: 2DPAPPA), N,N,N',N',N'',N '',N''',N'''-Octaphenyldibenzo[g,p]chrysene-2,7,10 ,15-tetraamine (abbreviation: DBC1), coumarin 30, N-(9,10-diphenyl -2-anthryl)-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2 PCAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-ant [Lyl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCABPh) A) N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl -1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(1,1 '-biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1, 4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(1,1'-bis( (phenyl-2-yl)-N-[4-(9H-carbazole-9-yl)phenyl]-N-f Phenylanthracene-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenyl Luanthracene-9-amine (abbreviation: DPhAPhA), Coumarin 6, Coumarin 545T N,N'-diphenylquinacridone (abbreviation: DPQd), rubren, 2,8-di-te rt-butyl-5,11-bis(4-tert-butylphenyl)-6,12-diphenyl Lutetracene (abbreviation: TBRb), Nile Red, 5,12-bis(1,1'-biphenyl Lu-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2- [4-(dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyran-4-yly Dene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3 ,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl ]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N ',N'-Tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-meth (p) acenaphtho[1,2-a]fluorantene-3,10-diamine (abbreviation: p -mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethicone)] Ru-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl )Ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI) , 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3, 6,7-Tetrahydro-1H,5H-Benzo[ij]quinoridine-9-yl)ethenyl -4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2, 6-Bis{2-[4-(dimethylamino)phenyl]ethenyl}-4H-pyran-4-i (Liden)propanedinitrile (abbreviation: BisDCM), 2-{2,6-bis[2-(8- Methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H -Benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene} Ropanedinitrile (abbreviation: BisDCJ™), 5,10,15,20-tetraphenyl Bisbenzo[5,6]indeno[1,2,3-cd:1',2',3'-lm]perylene These are some examples.

[0115] Guest material 132 (phosphorescent compound) can be iridium, rhodium, or platinum-based. Examples include organometallic complexes or metal complexes, among which organoiridium complexes, for example, iridium Um-based orthometallic complexes are preferred. 4H-triazo is a suitable ligand for orthometallation. 1H-triazole ligand, 1H-triazole ligand, imidazole ligand, pyridine ligand, pyrimi Examples include din ligands, pyrazine ligands, or isoquinoline ligands. Metal complexes Examples include platinum complexes containing porphyrin ligands.

[0116] Examples of substances that have a blue or green emission peak include tris{2-[5-(2 -methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazo [Ir-3-yl-κN2]phenyl-κC}iridium(III) (abbreviation: Ir(mpp) tz-dmp)3), Tris(5-methyl-3,4-diphenyl-4H-1,2,4-) Ryasolato) Iridium(III) (abbreviation: Ir(Mptz)3), Tris[4-(3- [Biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato] Lydium(III) (abbreviation: Ir(iPrptz-3b)3), Tris[3-(5-Bif [Phenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazolato]iridi Um(III) (abbreviation: Ir(iPr5btz)3), a 4H-triazole skeleton organometallic iridium complexes having, or tris[3-methyl-1-(2-methylphenyl) -5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: Ir (Mptz1-mp)3), Tris(1-methyl-5-phenyl-3-propyl-1H- 1,2,4-Triazolat) Iridium(III) (Abbreviation: Ir(Prptz1-Me) 3) Organometallic iridium complexes having a 1H-triazole skeleton, or fac-tri S[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole] Rydium(III) (abbreviation: Ir(iPrpmi)3), Tris[3-(2,6-dimethyl Iridium (I)-7-methylimidazo[1,2-f]phenantridinato]iridium II) (abbreviation: Ir(dmpimpt-Me)3) has an imidazole skeleton iridium metal complexes and bis[2-(4',6'-difluorophenyl)pyridinate- N,C 2’ Iridium(III) tetrakis(1 - pyrazolyl)borate (abbreviation: FI r6), bis[2-(4’,6’-difluorophenyl)pyridinato-N,C 2’ Iri dium(III) picolinate (abbreviation: FIrpic), bis{2-[3’,5’-bis (trifluoromethyl)phenyl]pyridinato-N,C 2’}iridium(III) pico linate (abbreviation: Ir(CF3ppy)2(pic)), bis[2-(4’,6’-dif luorophenyl)pyridinato-N,C 2’ iridium(III) acetylacetonate (abbreviation: FIr(acac)) and other phenylpyridine derivatives having an electron-withdrawing group as a ligand include organometallic iridium complexes. Among those described above, organometallic iridium complexes having a nitrogen-containing five-membered heterocyclic skeleton such as a 4H-triazole skeleton, a 1H-triazole skeleton, and an imidazole skeleton have high triplet excitation energy and are particularly preferable because of their high reliability and luminescence efficiency .

[0117] In addition, substances having a luminescence peak in green or yellow include, for example, tris(4-methyl -6-phenylpyrimidinato)iridium(III) (abbreviation: Ir(mppm)3), tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: I r(tBuppm)3), (acetylacetonato)bis(6-methyl-4-phenylpyr imidinato)iridium(III) (abbreviation: Ir(mppm)2(acac)), (acetyl acetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium( III) (abbreviation: Ir(tBuppm)2(acac)), (acetylacetonato)bis​ [4-(2-norbornyl)-6-phenylpyrimidinato]iridium(III) (abbreviation) :Ir(nbppm)2(acac)),(acetylacetonato)bis[5-methyl-6 -(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: Ir(mpmppm)2(acac)), (acetylacetonato)bis{4,6-dimethicone} Lu-2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN3]phenyl- κC} Iridium(III) (abbreviation: Ir(dmppm-dmp)2(acac)), ( Acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III)( Abbreviation: Organometallic irritants with a pyrimidine skeleton, such as Ir(dppm)2(acac) Dium complexes, and (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazine Iridium(III) (abbreviation: Ir(mppr-Me)2(acac)), (acetyl Luacetonato)bis(5-isopropyl-3-methyl-2-phenylpyradinato)iridi Pyrazine bones like Um(III) (abbreviation: Ir(mppr-iPr)2(acac)) iridium organometallic complexes with a specific classification, and tris(2-phenylpyridinato-N,C) 2’ ) Iridium(III) (abbreviation: Ir(ppy)3), bis(2-phenylpyridinate-N) ,C 2’ Iridium(III) acetylacetonate (abbreviation: Ir(ppy)2(ac ac)), bis(benzo[h]quinolinate)iridium(III)acetylacetonate (Abbreviation: Ir(bzq)2(acac)), Tris(benzo[h]quinolinato)iridium Mu(III) (abbreviation: Ir(bzq)3), Tris(2-phenylquinolinato-N,C) 2 ’ ) Iridium(III) (abbreviation: Ir(pq)3), bis(2-phenylquinolinazole- N,C 2’ Iridium(III) acetylacetonate (abbreviation: Ir(pq)2(ac) Organometallic iridium complexes having a pyridine skeleton, such as ac)), and bis(2,4-diph Enyl-1,3-oxazolato-N,C 2’ Iridium(III) Acetylaceton (abbreviation: Ir(dpo)2(acac)), bis{2-[4'-(perfluorophenicol) [Phenyl]pyridinate-N,C 2’ Iridium(III) acetylacetonate ( Abbreviation: Ir(p-PF-ph)2(acac)), bis(2-phenylbenzothiazolat -N,C 2’ Iridium(III) acetylacetonate (abbreviation: Ir(bt)2(a) In addition to organometallic iridium complexes such as CAC, there are also tris(acetylacetonate)(monophenate). Nanthroline terbium(III) (abbreviation: Tb(acac)3(Phen)) Examples include rare earth metal complexes. Among those mentioned above, organometallic ylids having a pyrimidine skeleton are particularly noteworthy. Dium complexes are particularly preferred because they offer outstanding reliability and luminous efficiency.

[0118] Furthermore, examples of substances that have a yellow or red emission peak include (diisobutyryl Methanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(II) I) (abbreviation: Ir(5mdppm)2(dibm)), bis[4,6-bis(3-methyl [Phenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: Ir (5 mdppm)2(dpm)), bis[4,6-di(naphthalene-1-yl)pyrimid Nat] (dipivaloylmethanato) Iridium(III) (Abbreviation: Ir(d1npm)2) Organometallic iridium complexes having a pyrimidine skeleton such as dpm, and (acetylacet Tonato)bis(2,3,5-triphenylpyradinato)iridium(III) (abbreviation: I r(tppr)2(acac)), bis(2,3,5-triphenylpyrazinate)(dipy Valoylmethanato) Iridium(III) (abbreviation: Ir(tppr)2(dpm)), ( Acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato] A pyrazine skeleton like lysium(III) (abbreviation: Ir(Fdpq)2(acac)) The organometallic iridium complexes and tris(1-phenylisoquinolinato-N,C) 2’ ) Iridium(III) (abbreviation: Ir(piq)3), bis(1-phenylisoquinolinate) -N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: Ir(piq)2( In addition to organometallic iridium complexes with a pyridine skeleton such as acac), 2, 3, 7, 8,12,13,17,18-Octaethyl-21H,23H-Porphyrin Platinum(II) Platinum complexes such as (abbreviation: PtOEP) and tris(1,3-diphenyl-1,3-p Europium(III) (Abbreviation: Eu(DB) M)3(Phen)), Tris[1-(2-tenoyl)-3,3,3-trifluoroacetate Tonato (monophenanthroline) europium(III) (abbreviation: Eu(TTA)3) Examples include rare earth metal complexes such as Phen). Among those mentioned above, the pyrimidine skeleton The organometallic iridium complex possesses outstanding reliability and luminescence efficiency, and is therefore particularly preferred. Furthermore, organometallic iridium complexes having a pyrazine skeleton can produce a red emission with good chromaticity. It is possible.

[0119] The light-emitting material included in the light-emitting layer 130 is capable of converting triplet excitation energy into light emission. A material is preferable. A material that can convert the triplet excitation energy into light emission is phosphorescent. In addition to chemical compounds, there are also thermally activated delayed fluorescence compounds. Ayed fluorescence (TADF) materials are an example. Therefore, phosphorescence Where it says "thermal-activated compound," you may substitute it with "thermal-activated delayed fluorescence material." Oh, thermally activated delayed fluorescence materials are materials with triplet excitation energy levels and singlet excitation energy levels. The difference is small, and the energy is transferred from the triplet excited state to the singlet excited state by reverse intersystem crossing. It is a material that has the function of converting. Therefore, it converts the triplet excited state into a small amount of thermal energy. Therefore, it is possible to upconvert to a singlet excited state (reverse intersystem crossing), and from the singlet excited state It can efficiently exhibit luminescence (fluorescence). Furthermore, thermally activated delayed fluorescence can be efficiently obtained. The conditions for this to occur are the energy levels of the triplet excitation energy level and the singlet excitation energy level. The difference is preferably greater than 0 eV and 0.2 eV or less, and more preferably greater than 0 eV and 0 One example is that the voltage is less than 0.1 eV.

[0120] When a thermally activated delayed fluorescence material is composed of only one type of material, for example, the following materials can be used. It is possible.

[0121] First, there are fullerenes and their derivatives, acridine derivatives such as proflavin, and eosin. It can be produced. Also, magnesium (Mg), zinc (Zn), cadmium (Cd), tin (S) n) Metals containing platinum (Pt), indium (In), or palladium (Pd), etc. Examples include metal-containing porphyrins. For example, protoporph Fluorine-tin fluoride complex (SnF2(Proto IX)), mesoporphyrin-fluoride Tin complex (SnF2(Meso IX)), hematoporphyrin-tin fluoride complex (Sn F2 (Hemato IX), coproporphyrin tetramethyl ester - tin fluoride Complex (SnF2(Copro III-4Me)), octaethylporphyrin-fluoride Tin complex (SnF2(OEP)), Ethioporphyrin-tin fluoride complex (SnF2(E Examples include tio I)) and octaethylporphyrin-platinum chloride complex (PtCl2OEP). It can be done.

[0122] Furthermore, as a thermally activated delayed fluorescence material composed of one type of material, a π-electron-rich complex atom is an example. Heterocyclic compounds having aromatic rings and π-electron-deficient heteroaromatic rings can also be used. Specifically is 2-(biphenyl-4-yl)-4,6-bis(12-phenylindoro[2,3- a)Carbazole-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol [9-yl]phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PC) CzPTzn), 2-[4-(10H-phenoxazine-10-yl)phenyl]-4, 6-Diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5- Phenyl-5,10-dihydrophenazine-10-yl)phenyl]-4,5-diphenyl Lu-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl- 9H-acridine-10-yl)-9H-xanthen-9-one (abbreviation: ACRXTN) , bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (Abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridine] Examples include -9,9'-anthracene]-10'-one (abbreviated as ACRSA). Because the cyclic compounds have π-electron-rich heteroaromatic rings and π-electron-deficient heteroaromatic rings, High transportability and hole transportability are desirable. In particular, a skeleton having a π-electron-deficient heteroaromatic ring is preferred. Among these, diazine skeletons (pyrimidine skeletons, pyrazine skeletons, pyridazine skeletons), or tri The azine skeleton is preferred because it is stable and reliable. Furthermore, the π-electron-rich heteroaromatic ring is also preferred. Among the skeletons it possesses, the acridine skeleton, phenoxazine skeleton, thiophene skeleton, and furan skeleton are particularly noteworthy. The pyrrole skeleton is stable and reliable, therefore any of the skeletons can be selected. It is preferable to have one or more of these. The pyrrole skeleton is indole. The skeleton, the carbazole skeleton, and 3-(9-phenyl-9H-carbazole-3-yl)- A 9H-carbazole skeleton is particularly preferred. Note that π-electron-rich heteroaromatic rings and π-electron-deficient rings are also preferred. Substances directly bonded to a type of heteroaromatic ring exhibit both donor and π-electron-deficient properties for π-electron-rich heteroaromatic rings. Both the acceptor properties of the complex aromatic ring are strong, and the energy levels of the singlet excited state and the triplet excited state are also strong. This is particularly preferable because it reduces the energy level difference from the initial state's energy level.

[0123] Furthermore, in the light-emitting layer 130, materials other than the host material 131 and the guest material 132 are used. It's okay to have it.

[0124] There are no particular limitations on the materials that can be used for the light-emitting layer 130, but for example, ant spiral derivatives, phenanthrene derivatives, pyrene derivatives, chrysene derivatives, dibenzo[g, Examples include condensed polycyclic aromatic compounds such as p]chrysene derivatives, specifically 9,10-diph Phenylanthracene (abbreviation: DPAnth), 6,12-dimethoxy-5,11-diphenylanthracene Nyl chrysene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: D PPA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 2-tert -butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 9, 9'-Biantril (abbreviation: BANT), 9,9'-(Stilben-3,3'-Zil) Diphenanthrene (abbreviation: DPNS), 9,9'-(stilben-4,4'-diyl)di Phenanthrene (abbreviation: DPNS2), 1,3,5-tri(1-pyrenyl)benzene (abbreviation) Examples include (name: TPB3). Furthermore, from among these and known substances, the above Singlet or triplet excitation energy levels higher than the excitation energy levels of guest material 132 One or more materials having excitation energy levels can be selected and used.

[0125] Furthermore, for example, a compound having a heteroaromatic skeleton such as an oxadiazole derivative is used in the light-emitting layer 1. It can be used in 30. Specifically, for example, 2-(4-biphenylyl)-5-(4 -tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), and 1 ,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole- 2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-o Xadiazole-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 4, 4'-Bis(5-methylbenzoxazol-2-yl)stilbene (abbreviation: BzOs) Examples of heterocyclic compounds include the following.

[0126] Furthermore, metal complexes containing heterocyclic rings (for example, zinc and aluminum-based metal complexes) emit light. It can be used in layer 130. For example, quinoline ligand, benzoquinoline ligand, oxy Examples include metal complexes having a sazole ligand or a thiazole ligand. Specifically, For example, tris(8-quinolinolato)aluminum(III) (abbreviation: Alq), tri (4-methyl-8-quinolinolato)aluminum(III) (abbreviation: Almq3), (10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq2) ), bis(2-methyl-8-quinolinolate)(4-phenylphenolate)aluminum ( III) (Abbreviation: BAlq), Bis(8-quinolinolato)zinc(II) (Abbreviation: Znq) Examples include metal complexes having a quinoline skeleton or a benzoquinoline skeleton. In addition, bis[2-(2-benzoxazolyl)phenolate]zinc(II) (abbreviation: ZnP) BO), bis[2-(2-benzothiazolyl)phenolate]zinc(II) (abbreviation: ZnB) Metal complexes with oxazole-based or thiazole-based ligands, such as TZ, are also used. It is possible.

[0127] The light-emitting layer 130 can also be composed of two or more layers. For example, the first When the first light-emitting layer and the second light-emitting layer are stacked in order from the hole transport layer side to form the light-emitting layer 130, A material having hole transport properties is used as the host material for the first light-emitting layer, and the host material for the second light-emitting layer This includes configurations that use materials with electron transport properties. Also, the first light-emitting layer and the second light-emitting layer The light-emitting material in the light layer may be the same material or different materials, and the same color light-emitting material may be emitted. Even if a material has the function of emitting light, it is a material that has the function of emitting light of different colors. It is also acceptable to use two light-emitting layers, each containing a light-emitting material that exhibits different colors of light emission. By using each of them, multiple light sources can be obtained simultaneously. In particular, the two light-emitting layers exhibit It is preferable to select the light-emitting material used in each light-emitting layer so that it becomes white due to the light emission.

[0128] The light-emitting layer 130 is produced by vapor deposition (including vacuum deposition), inkjet, coating, etc. It can be formed by methods such as labia printing. In addition to the materials mentioned above, quantum dots, etc. Even if it has an inorganic compound or polymer compound (oligomer, dendrimer, polymer, etc.) good.

[0129] ≪Hole Injection Layer≫ The hole injection layer 111 is a hole injection layer that receives holes from one of the pair of electrodes (electrode 101 or electrode 102). It has the function of promoting hole injection by reducing the injection barrier, for example, transition metal oxides, f It is formed by tarocyanine derivatives or aromatic amines, etc. Transition metal oxides and For example, molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide Examples include manganese oxides. Phthalocyanine derivatives include phthalocyanine and Examples include metal phthalocyanines. Aromatic amines include benzidine derivatives and phenyl Examples include lendiamine derivatives. Polymer compounds such as polythiophene and polyaniline. It is also possible to use substances, for example, self-doped polythiophenes such as poly(ethylenedi(ethylenedi) Typical examples include oxythiophene / poly(styrene sulfonic acid).

[0130] As the hole injection layer 111, a hole transport material and a material that exhibits electron-accepting properties in relation to it are combined. A layer containing composite material can also be used. Alternatively, a layer containing an electron-accepting material and a positive A lamination of layers containing pore-transporting material may also be used. Between these materials, a steady state or electrical current may be maintained. Charge transfer is possible in the presence of an electron barrier. Examples of materials exhibiting electron-accepting properties include Kinojimeta. Organic acceptors such as chloranil derivatives and hexaazatriphenylene derivatives We can list the following: Specifically, 7,7,8,8-tetracyano-2,3,5,6- Tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, 2,3,6,7, 10,11-Hexacyano-1,4,5,8,9,12-Hexazatriphenylene (abbreviated) These are compounds that have electron-withdrawing groups (halogen groups or cyano groups), such as HAT-CN. Furthermore, transition metal oxides, such as oxides of Group 4 to Group 8 metals, can be used. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, acid These include tungsten oxide, manganese oxide, and rhenium oxide. Among these, molybdenum oxide is particularly toxic to the atmosphere. Among them, it is preferable because it is stable, has low hygroscopicity, and is easy to handle.

[0131] As a hole-transporting material, a material with higher hole transport capabilities than electron transport can be used, ×10 -6 cm 2 It is preferable that the material has a hole mobility of / Vs or greater. Specifically Aromatic amines and calcine are listed as hole transport materials that can be used in the light-emitting layer 130. Basol derivatives, aromatic hydrocarbons, stilbene derivatives, etc., can be used. The hole-transporting material may be a polymer compound.

[0132] Other hole-transporting materials include aromatic hydrocarbons, such as 2-tert -butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2- tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3, 5-Diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9 ,10-Bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,1 0-Di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene Cene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAn) th), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA) , 2-tert-butyl-9,10-bis[2-(1-naphthyl)phenyl]anthrace n, 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7- Tetramethyl-9,10-di(1-naphthyl)anthracene, 2,3,6,7-tetramethyl Chil-9,10-di(2-naphthyl)anthracene, 9,9'-biantril, 10,1 0'-Diphenyl-9,9'-biantryl, 10,10'-bis(2-phenylphenyl Ru)-9,9'-Biantrill, 10,10'-Bis[(2,3,4,5,6-Pentaf [phenyl]-9,9'-bianthryl, anthracene, tetracene, rubrene, Examples include perylene and 2,5,8,11-tetra(tert-butyl)perylene. In addition, pentacene, coronene, etc. can also be used. -6 cm 2Aromatic hydrocarbons having a hole mobility of / Vs or greater and having 14 to 42 carbon atoms. It is preferable to use

[0133] Furthermore, aromatic hydrocarbons may have a vinyl skeleton. Examples of group hydrocarbons include 4,4'-bis(2,2-diphenylvinyl)biphenyl (Abbreviation: DPVBi), 9,10-bis[4-(2,2-diphenylvinyl)phenyl] Examples include anthracene (abbreviated as DPVPA).

[0134] Also, 4-{3-[3-(9-phenyl-9H-fluorene-9-yl)phenyl] Benzyl dibenzofuran (abbreviation: mmDBFFLBi-II), 4,4',4''-(be (Dibenzofuran) (abbreviation: DBF3P-II), 1,3,5-tri(dibenzothiophen-4-yl)benzene (abbreviation: DBT3P-II) ), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluorene-9-yl) [phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl Lu-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation) :DBTFLP-IV), 4-[3-(triphenylene-2-yl)phenyl]dibenzo Thiophene compounds such as thiophene (abbreviation: mDBTPTp-II), furan compounds, and flu Orene compounds, triphenylene compounds, phenanthrene compounds, etc., can be used. Among the compounds mentioned above, pyrrole skeleton, furan skeleton, thiophene skeleton, aromatic amine skeleton Compounds having this structure are stable, reliable, and therefore preferable. The material has high hole transport properties and also contributes to reducing the drive voltage.

[0135] ≪Hole transport layer≫ The hole transport layer 112 is a layer containing a hole transportable material, and is an example of the material used for the hole injection layer 111. The hole transport material shown can be used. The hole transport layer 112 is in the hole injection layer 111. Because it has the function of transporting the injected holes to the light-emitting layer 130, the HOM of the hole injection layer 111 O(Highest Occupied Molecular Orbital) It is preferable to have the same or close HOMO level as the occupying orbital level.

[0136] Also, 1 x 10 -6 cm 2 It is preferable that the substance has a hole mobility of / Vs or higher. However, other materials may be used as long as they have higher hole transport capabilities than electron transport. Furthermore, the layer containing the material with high hole transport properties may be a single layer, or a double layer consisting of the aforementioned material. You may stack more than this amount.

[0137] ≪Electron transport layer≫ The electron transport layer 118 passes through the electron injection layer 119 to the other of the pair of electrodes (electrode 101 or electron It has the function of transporting electrons injected from pole 102) to the light-emitting layer 130. Electron transport material For this purpose, materials with higher electron transport capabilities than holes can be used, resulting in 1 × 10⁻⁶ -6 cm 2 It is preferable that the material has an electron mobility of / Vs or higher. Examples of materials (materials with electron transport properties) include π-electron-deficient types such as nitrogen-containing heteroaromatic compounds. Hetero-aromatic compounds and metal complexes can be used. Specifically, they can be used in the light-emitting layer 130. Pyridine derivatives, bipyridine derivatives, and pyrimidines were listed as electron transport materials that can perform this function. Derivatives, triazine derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, phena Introlin derivatives, triazole derivatives, benzimidazole derivatives, oxadiazole Examples include derivatives. Also, 1 × 10 -6 cm 2 Objects with electron mobility of / Vs or greater It is preferable that the material is of a certain quality. However, any material that has higher electron transport capabilities than holes is acceptable, except as described above. The following materials may be used as the electron transport layer. Also, the electron transport layer 118 may be more than just a single layer. Two or more layers made of the above-mentioned material may be stacked.

[0138] Other examples include metal complexes having heterocyclic rings, such as quinoline ligands and benzoquinoline. Examples include metal complexes having ligands, oxazole ligands, or thiazole ligands. Specifically, for example, tris(8-quinolinolato)aluminum(III) (abbreviation: A lq), Tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviation: Al mq3), bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation) :BeBq2), bis(2-methyl-8-quinolinolate)(4-phenylphenolate) Luminium(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation) Examples include metal complexes having a quinoline skeleton or a benzoquinoline skeleton, such as Znq. In addition, bis[2-(2-benzoxazolyl)phenolate]zinc(II) Abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolate]zinc(II) Metal complexes having oxazole or thiazole ligands, such as (abbreviated as ZnBTZ) Other options can also be used.

[0139] Furthermore, a layer for controlling the movement of electron carriers is provided between the electron transport layer 118 and the light-emitting layer 130. It is also acceptable to use materials with high electron transport properties, as described above, and materials with high electron trapping properties. A layer to which a small amount of is added, thereby suppressing the movement of electron carriers, carrier balance This makes it possible to adjust the balance. In this configuration, electrons penetrate the light-emitting layer. This has a significant effect in suppressing problems that may arise as a result (for example, a decrease in the lifespan of the device).

[0140] ≪Electron injection layer≫ The electron injection layer 119 promotes electron injection by reducing the electron injection barrier from the electrode 102. It has the function of being, for example, Group 1 metals, Group 2 metals, or their oxides and halides. Carbonates and the like can be used. In addition, the electron transport material shown above and the electron transport material therefor Composite materials exhibiting electron-donating properties can also be used. Examples of electron-donating materials include: Examples include Group 1 metals, Group 2 metals, or oxides thereof. Specifically These are lithium fluoride (LiF), sodium fluoride (NaF), and cesium fluoride (CsF). ), calcium fluoride (CaF2), lithium oxide (LiO2) x ) and other alkali metals Alkaline earth metals, or compounds thereof can be used. Also, fluoride Rare earth metal compounds such as bium (ErF3) can be used. Furthermore, electron injection layers can be used. An electride may be used in 119. For example, calcium Examples include substances obtained by adding a high concentration of electrons to a mixed oxide of aluminum and luminum. The injection layer 119 may be made of a material that can be used in the electron transport layer 118.

[0141] Furthermore, the electron injection layer 119 is a composite made by mixing an organic compound and an electron donor. Materials may be used. Such composite materials are created when electrons are released from the organic compound by an electron donor. Therefore, it exhibits excellent electron injection and electron transport properties. In this case, as an organic compound... Preferably, the material is one that is excellent at transporting the generated electrons, specifically, for example, the material described above. The electron transport layer 118 can be composed of materials (such as metal complexes or heteroaromatic compounds). The electron donor can be any substance that exhibits electron-donating properties towards organic compounds. Alkali metals, alkaline earth metals, and rare earth metals are preferred, as are lithium and sodium. Examples include cesium, magnesium, calcium, erbium, and ytterbium. Furthermore, alkali metal oxides and alkaline earth metal oxides are preferred, as are lithium oxides and calcium oxides. Examples include sium oxide and barium oxide. Also, Lewis plates such as magnesium oxide. Bases can also be used. Additionally, organic compounds such as tetrathiafulvalene (abbreviated as TTF) can be used. Objects can also be used.

[0142] Furthermore, the above-mentioned light-emitting layer, hole injection layer, hole transport layer, electron transport layer, and electron injection layer are, These methods include vapor deposition (including vacuum deposition), inkjet printing, coating, and gravure printing. It can be formed by the above-mentioned method. In addition, the light-emitting layer, hole injection layer, hole transport layer, electron In addition to the materials mentioned above, the transport layer and electron injection layer also contain inorganic compounds such as quantum dots and high-molecular-weight materials. Sub-compounds (oligomers, dendrimers, polymers, etc.) may also be used.

[0143] Quantum dots Quantum dots are semiconductor nanocrystals ranging in size from a few nanometers to tens of nanometers, with a size of 1 × 10⁻¹⁶. 3 From 1 x 10 6 It is composed of about 100 atoms. The energy of a quantum dot depends on its size. Because of this shift, even quantum dots composed of the same material will emit different light waves depending on their size. The lengths are different. Therefore, by changing the size of the quantum dots used, light emission can be easily achieved. The wavelength can be changed.

[0144] Furthermore, quantum dots have a narrow peak width in their emission spectrum, resulting in emission with good color purity. It is possible. Furthermore, the theoretical internal quantum efficiency of quantum dots is said to be almost 100%. It accounts for a significant portion of the 25% of organic compounds that exhibit fluorescence, and the proportion of organic compounds that exhibit phosphorescence is much higher than that of organic compounds that exhibit phosphorescence. It is equivalent to a compound. Therefore, by using quantum dots as a light-emitting material... This allows us to obtain light-emitting elements with high luminescence efficiency. Moreover, quantum dots, which are inorganic materials, Furthermore, because of its excellent inherent stability, it is possible to obtain a desirable light-emitting element from the standpoint of lifespan. It is possible.

[0145] The materials that make up quantum dots include Group 14 elements, Group 15 elements, Group 16 elements, and composite Compounds consisting of elements from Group 14, and elements belonging to Groups 4 through 14 and Group 16. Compounds, compounds of Group 2 and Group 16 elements, compounds of Group 13 and Group 15 elements Compounds of Group 13 and Group 17 elements, compounds of Group 14 and Group 15 elements, Compounds of Group 11 and Group 17 elements, iron oxides, titanium oxides, chalcogenides Examples include semiconductor clusters and other similar devices.

[0146] Specifically, cadmium selenide, cadmium sulfide, cadmium telluride, and selenium sulfide. Lead, zinc oxide, zinc sulfide, zinc telluride, mercury sulfide, mercury selenide, mercury telluride, arsenic Indium, indium phosphide, gallium arsenide, gallium phosphide, indium nitride, nitride Gallium, indium antimonide, gallium antimonide, aluminum phosphide, arsenide Aluminum, aluminum antimonide, lead selenide, lead telluride, lead sulfide, selenide Indium, indium telluride, indium sulfide, gallium selenide, arsenic sulfide, sele Arsenic arsenide, arsenic telluride, antimony sulfide, antimony selenide, antimony telluride, Bismuth sulfide, bismuth selenide, bismuth telluride, silicon, silicon carbide, germanium M, tin, selenium, tellurium, boron, carbon, phosphorus, boron nitride, boron phosphide, boron arsenide Aluminum nitride, aluminum sulfide, barium sulfide, barium selenide, barium telluride Beryllium, calcium sulfide, calcium selenide, calcium telluride, beryllium sulfide, Beryllium selenide, beryllium telluride, magnesium sulfide, magnesium selenide, Germanium sulfide, germanium selenide, germanium telluride, tin sulfide, tin selenide tin telluride, lead oxide, copper fluoride, copper chloride, copper bromide, copper iodide, copper oxide, copper selenide, acid Nickel oxide, cobalt oxide, cobalt sulfide, iron oxide, iron sulfide, manganese oxide, molybdenum sulfide Density, vanadium oxide, tungsten oxide, tantalum oxide, titanium oxide, zirconium oxide Aluminum oxide, silicon nitride, germanium nitride, barium titanate, selenium and ammonium compounds. Compounds of lead and cadmium, compounds of indium, arsenic and phosphorus, cadmium, selenium and sulfur Compounds of cadmium, selenium, and tellurium, compounds of indium, gallium, and arsenic Compounds of indium, gallium, and selenium; compounds of indium, selenium, and sulfur; copper and Examples include compounds of ion and sulfur, and combinations thereof, but these include It is not limited. Furthermore, using so-called alloy-type quantum dots whose composition is expressed in any ratio. This is also good. For example, a quantum dot of cadmium, selenium, and sulfur alloy can be used by changing the elemental content ratio. By changing the emission wavelength, it is possible to alter the emission wavelength, making it one of the effective methods for obtaining blue light emission. There are two.

[0147] Quantum dot structures include core type, core-shell type, and core-multishell type. Either of these can be used, but another inorganic ion with a wider band gap can be used to cover the core. By forming a shell with the material, defects and dangling bones present on the nanocrystalline surface can be eliminated. The effects of the luminescence can be reduced. This greatly improves the quantum efficiency of the luminescence. It is preferable to use A-shell type or core-multi-shell type quantum dots. Examples of materials include zinc sulfide and zinc oxide.

[0148] Furthermore, because quantum dots have a high proportion of surface atoms, they are highly reactive and prone to aggregation. Therefore, a protective agent is attached to the surface of the quantum dot or a protective group is provided. It is preferable that the protective agent is attached or a protective group is provided. This prevents aggregation and increases solubility in the solvent. Furthermore, it reduces reactivity and electrical... It is also possible to improve stability. Examples of protective agents (or protective groups) include polio Polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene Polyoxyethylene alkyl ethers such as ethylene oleyl ether, tripropyl phosphate Fins, tributylphosphine, trihexylphosphine, trioctylphosphine, etc. Trialkylphosphines, polyoxyethylene n-octylphenyl ether, polio Polyoxyethylene alkylphenyl ethers such as xyethylene n-nonylphenyl ether Tel compounds, tri(n-hexyl)amines, tri(n-octyl)amines, tri(n-decyl) ) Tertiary amines such as amines, tripropylphosphine oxide, tributylphosphine Oxide, trihexylphosphine oxide, trioctylphosphine oxide, tridec Organophosphorus compounds such as sylphosphine oxide, polyethylene glycol dilaurate, Polyethylene glycol diesters such as polyethylene glycol distearate, and Organic nitrogen compounds such as nitrogen-containing aromatic compounds like pyridine, lutidine, colidine, and quinolines. , hexylamine, octylamine, decylamine, dodecylamine, tetradecylamine aminoalkanes such as hexadecylamine and octadecylamine, and dibutyl sulfide Dialkyl sulfides such as dipropyl sulfate, dipropyl sulfate such as dimethyl sulfoxide and dibutyl sulfoxide Organic sulfur compounds such as sulfur-containing aromatic compounds including sulfur sulfoxides and thiophenes, palmite Higher fatty acids such as tinic acid, stearic acid, and oleic acid, alcohols, and sorbitan fatty acid Polyesters, fatty acid-modified polyesters, tertiary amine-modified polyurethanes, polyethylene Examples include mines, etc.

[0149] Quantum dots have a larger band gap as their size decreases, so they can produce the desired wave. The size is adjusted appropriately to obtain sufficient light. Therefore, the emission of quantum dots shifts towards the blue side, that is, towards the higher energy side. By changing the size of the swatch, the wavelengths of the ultraviolet, visible, and infrared spectra can be adjusted. The emission wavelength can be adjusted across the region. The size (diameter) of the quantum dot is A range of 0.5 nm to 20 nm, preferably 1 nm to 10 nm, is commonly used. Furthermore, the narrower the size distribution of quantum dots, the narrower the emission spectrum becomes. This allows for emission with good color purity. Furthermore, the shape of the quantum dots is not particularly limited. It may be spherical, rod-shaped, disc-shaped, or any other shape. Note that a rod-shaped quantum dot is a quantum Since the rod has the function of exhibiting directional light, quantum rods are used as light-emitting materials. By doing so, it is possible to obtain a light-emitting element with better external quantum efficiency.

[0150] By the way, in organic EL elements, the light-emitting material is often dispersed in the host material, and the light-emitting material By suppressing density quenching, the luminescence efficiency is increased. The host material is superior to the luminescent material. The material must have a doublet or triplet excitation energy level. In particular, when using blue phosphorescent materials as light-emitting materials, further triplet excitations occur. A host material is needed that has energy levels and is also excellent in terms of lifespan, and its development is It is extremely difficult. Here, the quantum dot emits light using only the quantum dot itself, without using a host material. Because it can maintain luminescence efficiency even when layers are formed, this is also preferable from the standpoint of lifespan. A light-emitting element can be obtained. When the light-emitting layer is formed using only quantum dots, the quantum dots The structure is preferably a core-shell structure (including a core-multi-shell structure).

[0151] When quantum dots are used as the light-emitting material for the light-emitting layer, the film thickness of the light-emitting layer is 3 nm to 100 nm. The n-thickness is preferably 10 nm to 100 nm, and the quantum dot content in the light-emitting layer is 1 to 1 The volume percentage is set to 00%. However, it is preferable to form the light-emitting layer using only quantum dots. When forming a light-emitting layer by dispersing the quantum dots as a light-emitting material in a host, the host material Disperse quantum dots in a suitable liquid medium, or dissolve the host material and quantum dots in a suitable liquid medium. Dispersed wet processes (spin coating, casting, die coating, blade coating) Coating method, roll coating method, inkjet method, printing method, spray coating method, curtain coating It can be formed by methods such as the stencil method or the Langmuir-Bludget method. Phosphorescent luminescent material For the light-emitting layer using the above wet process, vacuum deposition is also suitably used. It is possible.

[0152] Examples of liquid media used in wet processes include methyl ethyl ketone and cyclohexyl ester. Ketones such as xanone, fatty acid esters such as ethyl acetate, and halogens such as dichlorobenzene Aromatic hydrocarbons such as toluene, xylene, mesitylene, and cyclohexylbenzene. Hydrocarbons, aliphatic hydrocarbons such as cyclohexane, decalin, and dodecane, dimethylform Organic solvents such as humic acid (DMF) and dimethyl sulfoxide (DMSO) can be used. Cut.

[0153] ≪A pair of electrodes≫ Electrodes 101 and 102 function as the anode or cathode of the light-emitting element. 101 and electrode 102 are made of metals, alloys, conductive compounds, and mixtures or laminates thereof. It can be formed using [a specific method / tool].

[0154] Either electrode 101 or electrode 102 is formed by a conductive material having the function of reflecting light. Preferably, this is done. The conductive material is aluminum (Al) or an alloy containing Al. Examples include gold. Alloys containing Al include Al and L (where L is titanium (Ti) and neodymium). Includes (one or more of the following elements: Nd, Ni, and La) Examples include alloys containing Al and Ti, or Al, Ni, and La. Aluminum has low resistance and high light reflectivity. Also, aluminum is found in the Earth's crust. Because it is abundant and inexpensive, using aluminum reduces the cost of manufacturing light-emitting devices. It can reduce the amount of silver (Ag), or Ag and N (N is yttrium). Y), Nd, Magnesium (Mg), Ytterbium (Yb), Al, Ti, Gallium ( Ga), zinc (Zn), indium (In), tungsten (W), manganese (Mn), Tin (Sn), iron (Fe), nickel, copper (Cu), palladium (Pd), iridium (Ir ), or alloys containing one or more gold (Au) may be used. Examples of alloys include alloys containing silver, palladium, and copper, alloys containing silver and copper, and alloys containing silver and magnesium. Alloys containing nesium, alloys containing silver and nickel, alloys containing silver and gold, and alloys containing silver and ytterbium Examples include alloys containing tungsten, chromium (Cr), and molybdenum (Mo). ), transition metals such as copper and titanium can be used.

[0155] Furthermore, the light emitted from the light-emitting layer passes through one or both of electrodes 101 and 102. It is then removed. Therefore, at least one of electrode 101 or electrode 102 transmits light. Preferably, it is formed from a conductive material having a conductive function. The conductive material is preferably a conductive material. The light transmittance is 40% or more and 100% or less, preferably 60% or more and 100% or less, Its resistivity is 1 × 10 -2 Examples include conductive materials with a conductivity of Ω·cm or less.

[0156] Furthermore, electrodes 101 and 102 have the function of transmitting light and the function of reflecting light. It may be formed from a conductive material having a visible light reflectance of 20. The resistivity is between % and 80%, preferably between 40% and 70%, and its resistivity is 1 × 10⁻⁶. -2 Examples of conductive materials include those with a conductivity of Ω·cm or less. For example, conductive metals, alloys, and conductive materials. It can be formed using one or more types of chemical compounds. Specifically, for example, Indium tin oxide (ITO), silicon, or silicon oxide Indium tin oxide (abbreviated as ITSO), indium oxide-zinc oxide (Indi Indium-tin oxide containing titanium (indium zinc oxide), indium Metals such as indium oxide containing titanium oxide, tungsten oxide, and zinc oxide. Oxides can be used. Also, the degree to which light is transmitted (preferably 1 nm to 30 nm) A thin metal film with a thickness of m or less can be used. Examples of metals include Ag, or Alloys such as Ag and Al, Ag and Mg, Ag and Au, and Ag and Yb can be used.

[0157] In this specification, etc., a material having the function of transmitting light is defined as a material having the function of transmitting visible light. Any material that has and is conductive is acceptable, for example, ITO as described above. In addition to oxide conductors, the collection includes oxide semiconductors or organic conductors containing organic materials. Examples of organic conductors include those obtained by mixing an organic compound with an electron donor. Examples include composite materials, such as composite materials formed by mixing organic compounds with electron acceptors. It is possible to use inorganic carbon-based materials such as graphene. Preferably, the ratio is 1 × 10⁻⁶. 5 Ω·cm or less, more preferably 1 × 10⁻⁶ 4 Ω·cm The following applies:

[0158] Furthermore, by stacking multiple of the above materials, one of the electrodes 101 and 102 can be made They may form both.

[0159] Furthermore, in order to improve the light extraction efficiency, the electrode having a light-transmitting function is brought into contact with the A material with a refractive index higher than that of the electrode may be formed. Such a material may transmit visible light. Any material that has the function of being conductive is acceptable, and even if it is a conductive material, it does not have that function. Other options include oxide conductors, oxide semiconductors, and organic materials. Examples of organic materials include the light-emitting layer, hole injection layer, hole transport layer, electron transport layer, or electric Examples of materials used in the sub-injection layer include inorganic carbon-based materials and metals that are transparent to light. Thin films can also be used, and multiple layers of several nanometers to tens of nanometers in thickness may be stacked.

[0160] When electrode 101 or electrode 102 functions as a cathode, the work function is small. It is preferable that the material has a (3.8 eV or less) energy. For example, it is preferable that it has elements from Group 1 or Group 2 of the periodic table. Elements belonging to the group (alkali metals such as lithium, sodium, and cesium, calcium, stoichiometric compounds) Alkaline earth metals such as rontium, magnesium, etc., and alloys containing these elements (for example, Rare earth metals such as Ag and Mg, Al and Li, europium (Eu), Yb, and these rare earths Metal alloys, aluminum alloys, silver alloys, etc., can be used.

[0161] Furthermore, when electrode 101 or electrode 102 is used as the anode, the work function is large (4. It is preferable to use a material with a voltage of 0 eV or higher.

[0162] Furthermore, electrodes 101 and 102 are made of a conductive material that has the function of reflecting light and a material that transmits light. It may also be laminated with a conductive material having a function of passing through. In that case, electrode 101 and electrode 1 02 can resonate the light of a desired wavelength from each light-emitting layer, thereby intensifying the light of the desired wavelength. It is preferable because it can have a function to adjust the optical distance.

[0163] The methods for forming the film of electrodes 101 and 102 include sputtering, vapor deposition, printing, and coating. MBE (Molecular Beam Epitaxy), CVD, Pulse Ray The deposition method, ALD (Atomic Layer Deposition), etc., are used as appropriate. It is possible.

[0164] Circuit board Furthermore, a light-emitting element according to one aspect of the present invention is placed on a substrate made of glass, plastic, or the like. It is fine to manufacture it. In terms of the order in which it is manufactured on the substrate, it is fine to stack them in order from the electrode 101 side. You may also stack them sequentially starting from pole 102.

[0165] Examples of substrates on which a light-emitting element according to one aspect of the present invention can be formed include glass and quartz. , or plastic can be used. A flexible substrate may also be used. A substrate is a flexible substrate that can be bent, for example, polycarbonate Examples include plastic substrates made of nate, polyarylate, etc. Also, films, Inorganic vapor-deposited films can also be used. Note: The manufacturing process for light-emitting elements and optical elements. Anything other than these that functions as a support in the context is acceptable. Alternatively, Any device that has the function of protecting optical elements and other optical components is acceptable.

[0166] For example, in this specification, various substrates can be used to form light-emitting elements. The type of substrate is not particularly limited. One example of such a substrate is a semiconductor substrate (e.g., single-layer semiconductor substrate). Crystal substrate or silicon substrate), SOI substrate, glass substrate, quartz substrate, plastic substrate, gold Substrates, stainless steel substrates, substrates with stainless steel foil, tungsten Tungsten substrate, substrate having tungsten foil, flexible substrate, laminated film, fiber Examples include paper or substrate films containing a material of a certain type. An example of a glass substrate is barium. Examples include borosilicate glass, aluminoborsilicate glass, or soda-lime glass. Examples of flexible substrates, laminated films, and base films include the following: For example, polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). , typified by polyethersulfone (PES) and polytetrafluoroethylene (PTFE) There are plastics that can be made of acrylic or other resins. For example, polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride Examples include polyamide, polyimide, aramid, epoxy, etc. Examples include inorganic vapor-deposited films or paper products.

[0167] Alternatively, a flexible substrate may be used as the substrate, and the light-emitting element may be formed directly on the flexible substrate. Alternatively, a release layer may be provided between the substrate and the light-emitting element. The release layer is provided on top of the light-emitting element. After partially or completely completing the child component, it is separated from the circuit board and used for transferring it to another circuit board. This allows for the transfer of light-emitting elements to substrates with poor heat resistance or flexible substrates. Oh, the aforementioned delamination layer has, for example, a laminated inorganic film structure of a tungsten film and a silicon oxide film. Configurations such as the one shown, or a configuration in which a resin film such as polyimide is formed on the substrate, can be used.

[0168] In other words, a light-emitting element is formed using one substrate, and then the light-emitting element is transferred to another substrate. The light-emitting element may be placed on a different substrate. An example of a substrate on which the light-emitting element is placed is the above In addition to the substrates mentioned above, there are also cellophane substrates, stone substrates, wood substrates, and cloth substrates (natural fibers (silk, cotton, Hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate) (including t, cupro, rayon, recycled polyester, etc.), leather substrate, or rubber substrate. These substrates can be used to create light-emitting elements that are less prone to breakage and have high heat resistance. This can be a child, a lightweight light-emitting element, or a thinned light-emitting element.

[0169] Furthermore, a field-effect transistor (FET), for example, is formed on the aforementioned substrate, and the FET and The light-emitting element 150 may be fabricated on electrically connected electrodes. This allows the FET to This allows us to create an active-matrix type display device that controls the driving of the light-emitting element 150.

[0170] In this embodiment, one aspect of the present invention has been described. Or, other embodiments may be described. In this context, one aspect of the present invention will be described. However, this aspect of the present invention is not limited to these. Not done. In other words, various aspects of the invention are described in this embodiment and other embodiments. Therefore, one aspect of the present invention is not limited to a specific aspect. For example, one aspect of the present invention While an example of its application to a light-emitting element has been shown, one aspect of the present invention is not limited thereto. For example, depending on the circumstances, one aspect of the present invention may be suitable for a light-emitting element. It is not necessary to use it. Alternatively, for example, in one aspect of the present invention, a first organic compound and a second The material comprises an organic compound and a guest material, wherein the first organic compound has a nitrogen-containing six-membered heteroaromatic skeleton. The second organic compound has at least a nitrogen-containing five-membered heterocyclic skeleton or a tertiary amine skeleton. An example of a case having one has been shown, but one aspect of the present invention is not limited thereto. Alternatively, depending on the circumstances, in one aspect of the present invention, for example, the invention may not contain a second organic compound. Alternatively, the first organic compound does not need to have a nitrogen-containing six-membered heteroaromatic skeleton. Alternatively, the second organic compound may have a nitrogen-containing five-membered heterocyclic skeleton and a tertiary amine skeleton. It is not necessary. Alternatively, for example, in one aspect of the present invention, a nitrogen-containing five-membered heterocycle having an NH group. The content of the organic compound containing a skeleton or secondary amine skeleton is, by weight, relative to the first organic compound. An example of a ratio of 0.03 or less has been shown, but one aspect of the present invention is not limited thereto. In some cases, or depending on the circumstances, one aspect of the present invention provides a nitrogen-containing pentagon having an NH group. The content of organic compounds containing a heterocyclic skeleton or a secondary amine skeleton is compared to the first organic compound. The weight ratio may be greater than 0.03.

[0171] The configuration shown in this embodiment can be used in appropriate combination with other embodiments. Cut.

[0172] (Embodiment 2) In this embodiment, the light-emitting element has a configuration different from that shown in Embodiment 1. The light-emitting mechanism of the said light-emitting element will be explained below with reference to Figures 6 to 8. In Figures 6 to 8, parts having the same function as those shown in Figure 1(A) are indicated by the same symbols. A hatch pattern may be used, and the symbols may be omitted. Also, in areas with similar functions, Similar symbols may be used, and their detailed explanations may be omitted.

[0173] <Example of light-emitting element configuration 1> Figure 6(A) is a schematic cross-sectional view of the light-emitting element 250.

[0174] The light-emitting element 250 shown in Figure 6(A) has a pair of electrodes (electrode 101 and electrode 102) between them. , multiple light-emitting units (in Figure 6(A), light-emitting unit 106 and light-emitting unit 1 08) has. One of the multiple light-emitting units is an EL layer 10 It is preferable to have a configuration similar to that of 0. In other words, the light-emitting element 150 shown in Figure 1 is one It has a light unit, and it is preferable that the light-emitting element 250 has multiple light-emitting units. In the light-emitting element 250, electrode 101 functions as the anode and electrode 102 functions as the cathode. As explained below, the configuration of the light-emitting element 250 can also be reversed.

[0175] Furthermore, in the light-emitting element 250 shown in Figure 6(A), the light-emitting unit 106 and the light-emitting unit 108 is stacked, and between the light-emitting unit 106 and the light-emitting unit 108 there is an electric current A bio-layer 115 is provided. Note that the light-emitting unit 106 and the light-emitting unit 108 have the same configuration. However, a different configuration is also acceptable. For example, the light-emitting unit 106 may have a configuration similar to that of the EL layer 100. It is preferable to use it.

[0176] Furthermore, the light-emitting element 250 has a light-emitting layer 120 and a light-emitting layer 170. In addition to the light-emitting layer 170, knit 106 also includes a hole injection layer 111, a hole transport layer 112, and an electron transport layer. It has a layer 113 and an electron injection layer 114. The light-emitting unit 108 also has a light-emitting layer 120 In addition, there is a hole injection layer 116, a hole transport layer 117, an electron transport layer 118, and an electron injection layer 11 It has 9.

[0177] The charge generation layer 115 is a hole transport material to which an acceptor substance, which is an electron acceptor, is added. Even with such a configuration, the electron transport material is combined with a donor substance that acts as an electron donor. This is also acceptable. Furthermore, both of these configurations may be stacked.

[0178] If the charge generation layer 115 contains a composite material of an organic compound and an acceptor substance, The composite material used is a composite material that can be used in the hole injection layer 111 shown in Embodiment 1. That's all. As for organic compounds, aromatic amine compounds, carbazole compounds, aromatic carbon compounds Various compounds are used, such as hydrogen and polymer compounds (oligomers, dendrimers, polymers, etc.). It can exist. Furthermore, as an organic compound, its hole mobility is 1 × 10⁻⁶. -6 cm 2 / Vs It is preferable to apply materials that meet the above criteria. However, materials that have higher hole transport capabilities than electron transport capabilities. If so, other materials may be used. Composite materials of organic compounds and acceptor substances. Because the material has excellent carrier injection and carrier transport properties, it enables low-voltage and low-current operation. This can be achieved. Furthermore, the anode side of the light-emitting unit is in contact with the charge generation layer 115. In this case, the charge generation layer 115 also plays the role of a hole injection layer or hole transport layer of the light-emitting unit. Therefore, the light-emitting unit is configured without a hole injection layer or a hole transport layer. That is also acceptable. Alternatively, if the cathode side of the light-emitting unit is in contact with the charge generation layer 115. This means that the charge generation layer 115 also plays the role of an electron injection layer or electron transport layer of the light-emitting unit. Therefore, the light-emitting unit is configured without an electron injection layer or an electron transport layer. That's good too.

[0179] Furthermore, the charge generation layer 115 is a layer containing a composite material of an organic compound and an acceptor substance, and other It may be formed as a laminated structure by combining layers made of the following materials. For example, organic A layer containing a composite material of a compound and an acceptor substance, and one selected from among electron-donating substances. A layer containing the compound and a compound with high electron transport properties may be formed by combining them. A layer containing a composite material of an organic compound and an acceptor substance is combined with a layer containing a transparent conductive film. They may be formed together.

[0180] Furthermore, the charge generation layer 115 sandwiched between the light-emitting unit 106 and the light-emitting unit 108 is electric When a voltage is applied to electrode 101 and electrode 102, electrons are injected into one of the light-emitting units. Any method that injects holes into the other light-emitting unit is acceptable. For example, in Figure 6(A), When a voltage is applied such that the potential of electrode 101 is higher than the potential of electrode 102, The charge generation layer 115 injects electrons into the light-emitting unit 106 and holes into the light-emitting unit 108. Enter.

[0181] Furthermore, the charge generation layer 115 has light transmission to visible light (specifically) from the viewpoint of light extraction efficiency. It is preferable that the charge generation layer 115 has a visible light transmittance of 40% or more. Furthermore, the charge generation layer 115 has lower conductivity than the pair of electrodes (electrode 101 and electrode 102). It still works.

[0182] By forming the charge generation layer 115 using the materials described above, the light-emitting layer is stacked in the field This can suppress the rise in drive voltage during operation.

[0183] Furthermore, Figure 6(A) illustrates a light-emitting element having two light-emitting units. However, the same principle can also be applied to light-emitting elements that have three or more light-emitting units stacked on top of each other. As shown in the light-emitting element 250, multiple light-emitting units are placed between a pair of electrodes in a charge generation layer. By partitioning and arranging the elements, high-brightness light emission is possible while maintaining a low current density, and further This enables the creation of light-emitting elements with a long lifespan. Furthermore, it enables the creation of light-emitting elements with low power consumption. .

[0184] Furthermore, of the multiple units, at least one unit has the configuration shown in Embodiment 1. By applying this technology, we can provide light-emitting elements with high luminous efficiency and high reliability. It is possible.

[0185] In this embodiment, the light-emitting layer 170 of the light-emitting unit 106 is as shown in Embodiment 1. The light-emitting layer 130 will be described as having the following configuration. In this way, the light-emitting element 250 will emit This is suitable as a light-emitting element with high light efficiency and reliability.

[0186] Furthermore, the light-emitting layer 120 of the light-emitting unit 108 is, as shown in Figure 6(B), host The material comprises material 121 and guest material 122. The guest material 122 is a fluorescent compound. I will now explain further.

[0187] ≪Light-emitting mechanism of light-emitting layer 120≫ The light-emitting mechanism of the light-emitting layer 120 will be explained below.

[0188] A pair of electrodes (electrode 101 and electrode 102) or electricity injected from the charge generation layer 115 Excitons are generated when electrons and holes recombine in the light-emitting layer 120. Since host material 121 is present in large quantities compared to material 122, the generation of excitons is also An excited state is formed in the host material 121.

[0189] An exciton is a pair of carriers (electron and hole). An exciton has energy. Therefore, the material from which excitons are generated enters an excited state.

[0190] If the excited state of the formed host material 121 is a singlet excited state, then the host material 12 Singlet excitation energy is transferred from the S1 level of material 1 to the S1 level of guest material 122. Then, a singlet excited state is formed in guest material 122.

[0191] Since guest material 122 is a fluorescent compound, singlet excitation occurs in guest material 122. Once the state is formed, the guest material 122 rapidly emits light. At this time, high luminescence efficiency is obtained. To achieve this, it is preferable that the fluorescence quantum yield of guest material 122 is high. In case 122, when carriers recombine and the resulting excited state is a singlet excited state, It is the same.

[0192] Next, when a triplet excited state of the host material 121 is formed by carrier recombination... This will be explained. The energy levels of the host material 121 and guest material 122 in this case. The correlation of the positions is shown in Figure 6(C). The notation and symbols in Figure 6(C) are as follows: Furthermore, the T1 level of the host material 121 is lower than the T1 level of the guest material 122. Since this is preferable, Figure 6(C) illustrates this case, but the T1 level of the host material 121 This may be higher than the T1 level of guest material 122.

[0193] • Host(121): Host material 121 • Guest (122): Guest material 122 (fluorescent compound) ·S FH : S1 level of host material 121 ·T FH :T1 level of host material 121 ·S FG : S1 level of guest material 122 (fluorescent compound) ·T FG : T1 level of guest material 122 (fluorescent compound)

[0194] As shown in Figure 6(C), triplet-triplet annihilation (TTA: Triplet-Tripl Triplets generated by carrier recombination (et Annihilation) Excitons interact with each other, exchanging excitation energy and spin angular momentum. By doing so, the S1 level of the host material 121 (S FH ) has the energy A reaction occurs that converts to a singlet exciton (see Figure 6(C) TTA). Host material 121 The singlet excitation energy of is S FH Therefore, guest material 122 has lower energy. S1 level (S FG Energy transfer occurs to (see Figure 6(C) Route E5), and the guest A singlet excited state is formed in material 122, and guest material 122 emits light.

[0195] Furthermore, if the density of triplet excitons in the light-emitting layer 120 is sufficiently high (for example, 1 × 10⁻¹⁰ 12 cm -3 (The above) ignores the deactivation of a single triplet exciton and considers two closely spaced triplet excitations. We can consider only the child's response.

[0196] Furthermore, when carriers recombine in guest material 122 and a triplet excited state is formed... The triplet excited state of guest material 122 is thermally deactivated, making it difficult to utilize for luminescence. However, the T1 level (T) of the host material 121 FH ) is a guest material 122 T1 standard Place(T FG If it is lower than ), the triplet excitation energy of guest material 122 is lower than guest material 1 22 T1 levels (T FG ) from the T1 level of host material 121 (T FH Energy transfer to ) It is possible to do this (see Figure 6(C) Route E6), and it is then used for TTA.

[0197] In other words, the host material 121 is excited by TTA, and the triplet excitation energy is singlet excitation energy It is preferable that it has the function of converting into energy. By doing so, the light generated in the light-emitting layer 120 A portion of the triplet excitation energy is obtained by singlet excitation energy in the host material 121 via TTA. By converting it into energy and transferring the singlet excitation energy to the guest material 122, fluorescence It becomes possible to extract it as luminescence. To do this, the S1 level (S) of the host material 121 is required. FH ) is the S1 level (S FG It is preferable that it is higher than ) Also, phos T1 level of material 121 (T FH ) is the T1 level of guest material 122 (TFG ) lower It is preferable.

[0198] In particular, the T1 level of guest material 122 (T FG ) is the T1 level of the host material 121 ( T FH If it is lower than ), the weight ratio of host material 121 to guest material 122 is It is preferable that the weight ratio of guest material 122 is low. Specifically, the content of guest material 122 The amount is preferably greater than 0 and 0.05 or less in weight ratio to the host material 121. This reduces the probability of carrier recombination in guest material 122. Furthermore, the T1 level of the host material 121 (T FH ) from guest material 122 T1 level (T FG ) This can reduce the probability of energy transfer occurring.

[0199] The host material 121 may be composed of a single compound, or it may be composed of multiple compounds. It's fine if it's done.

[0200] Furthermore, the light-emitting unit 106 and the light-emitting unit 108 have guest materials with different light-emitting colors. In this case, the emission from the light-emitting layer 120 is on the shorter wavelength side than the emission from the light-emitting layer 170. It is preferable to have a configuration that has a -. A material having a high triplet excitation energy level The light-emitting element used tends to degrade in brightness quickly. Therefore, a light-emitting layer that exhibits short wavelength emission is used. By using TA, it is possible to provide light-emitting elements with minimal brightness degradation.

[0201] Furthermore, the light-emitting layer 170 has the same configuration as the light-emitting layer 130 shown in Embodiment 1, and the same configuration as the light-emitting layer 120. It can have a configuration.

[0202] <Example of light-emitting element configuration 2> Figure 7(A) is a schematic cross-sectional view of the light-emitting element 252.

[0203] The light-emitting element 252 shown in Figure 7(A) is similar to the light-emitting element 250 shown earlier, and consists of a pair of electrodes. Between electrodes 101 and 102, there are multiple light-emitting units (in Figure 7(A), It has a light unit 106 and a light-emitting unit 110). At least one light-emitting unit is , it has a similar configuration to the EL layer 100. Furthermore, the light-emitting unit 106 and light-emitting unit 110 The configuration can be the same or different.

[0204] Furthermore, in the light-emitting element 252 shown in Figure 7(A), the light-emitting unit 106 and the light-emitting unit 110 and are stacked, and between the light-emitting unit 106 and the light-emitting unit 110 there is an electric current A raw layer 115 is provided. For example, the light-emitting unit 106 has a configuration similar to that of the EL layer 100. It is preferable to use it.

[0205] Furthermore, the light-emitting element 252 has a light-emitting layer 140 and a light-emitting layer 170. In addition to the light-emitting layer 170, knit 106 also includes a hole injection layer 111, a hole transport layer 112, and an electron transport layer. It has a layer 113 and an electron injection layer 114. The light-emitting unit 110 also has a light-emitting layer 140 In addition, there is a hole injection layer 116, a hole transport layer 117, an electron transport layer 118, and an electron injection layer 11 It has 9.

[0206] Furthermore, of the multiple units, at least one unit has the configuration shown in Embodiment 1. By applying this technology, we can provide light-emitting elements with high luminous efficiency and high reliability. It is possible.

[0207] Furthermore, it is preferable that the light-emitting layer of the light-emitting unit 110 contains a phosphorescent compound. That is, The light-emitting layer 140 of the light-emitting unit 110 contains a phosphorescent compound, and the light-emitting unit 106 The light-emitting layer 170 has preferably the same configuration as the light-emitting layer 130 shown in Embodiment 1. The following describes an example of the configuration of the light-emitting element 252 in this case.

[0208] The light-emitting layer 140 of the light-emitting unit 110 is made of host material 1, as shown in Figure 7(B). It comprises 41 and a guest material 142. Furthermore, the host material 141 is an organic compound 141_ It comprises 1 and organic compound 141_2. Note that the guest material 14 of the light-emitting layer 140 Compound 2 is a phosphorescent compound, which will be explained below.

[0209] ≪Light-emitting mechanism of light-emitting layer 140≫ Next, the light-emitting mechanism of the light-emitting layer 140 will be explained below.

[0210] The organic compound 141_1 and organic compound 141_2 present in the light-emitting layer 140 form an excited complex. It is preferable to form [this].

[0211] The combination of organic compound 141_1 and organic compound 141_2 forms excited complexes with each other. Any combination that is possible is acceptable, but one of the compounds must be a hole-transporting compound. It is more preferable that the other compound is an electron-transporting compound.

[0212] Organic compound 141_1, organic compound 141_2, and guest material in the light-emitting layer 140 The correlation of energy levels with 142 is shown in Figure 7(C). Note that the notation in Figure 7(C) and The symbols are as follows: ·Host(141_1): Organic compound 141_1 (host material) ·Host(141_2): Organic compound 141_2 (host material) • Guest (142): Guest material 142 (phosphorescent compound) ·S PH1 : S1 level of organic compound 141_1 (host material) ·T PH1 :T1 level of organic compound 141_1 (host material) ·S PH2 : S1 level of organic compound 141_2 (host material) ·T PH2 :T1 level of organic compound 141_2 (host material) ·T PG : T1 level of guest material 142 (phosphorescent compound) ·S PE : S1 level of the excited complex ·T PE : T1 level of the excited complex

[0213] Organic compound 141_1 and organic compound 141_2 form an excited complex, and the S of the excited complex Level 1 (S PE ) and T1 level (T PE ) are adjacent energy levels (Figure 7( C) See Route E7.

[0214] Organic compound 141_1 and organic compound 141_2 receive holes and electrons, one receives a hole and the other receives an electron. By removing it, an excited complex is quickly formed. Alternatively, once one of them enters an excited state, It forms an excited complex by interacting with the other. Therefore, the excited complex in the luminescent layer 140 Most of the risers exist as excited complexes. The excitation energy levels of the excited complexes (S PE Also is T PE ) is a host material (organic compound 141_1 and organic compound 1) that forms an excited complex. 41_2) S1 level (S PH1 and S PH2 ) is lower, therefore lower excitation energy Ghee makes it possible to form an excited state of the host material 141. This makes it possible to emit light The drive voltage of the child can be reduced.

[0215] And the excited complex (S PE ) and (T PE The energy of both ) is used by guest material 142 Luminescence can be obtained by shifting to the T1 level of (phosphorescent compound) (Figure 7(C) Route E8, E See 9).

[0216] Note that the T1 level of the excited complex (T PE ) is the T1 level of guest material 142 (T PG )twist A larger value is preferable. This increases the singlet excitation energy of the generated excited complex. The triplet excitation energy is the S1 level (S) of the excited complex. PE ) and T1 level (T PE )mosquito The T1 level of guest material 142 (T PG Energy can be transferred to ).

[0217] Furthermore, in order to efficiently transfer excitation energy from the excited complex to the guest material 142, , the T1 level of the excited complex (T PE ) forms an excited complex with each organic compound (organic compound 14 T1 level of 1_1 and organic compound 141_2) (T PH1 and T PH2 ) is equivalent to, Smaller is preferable. This allows each organic compound (organic compound 141_1 and organic Compound 141_2) makes it less likely for the triplet excitation energy of the excited complex to quench. This allows for efficient energy transfer from the excited complex to the guest material 142.

[0218] Furthermore, organic compound 141_1 and organic compound 141_2 efficiently form an excited complex. In order to do so, the HOMO level of one of the organic compounds 141_1 and 141_2 must The fact that one LUMO level is higher than the other HOMO level, and one LUMO level is higher than the other LUMO level. Preferred. For example, if organic compound 141_1 has hole transport properties, and organic compound 141_2 is If it has electron transport properties, the HOMO level of organic compound 141_1 is the same as that of organic compound 141_2 It is preferable that the LUMO level is higher than the HOMO level, and the LUMO level of organic compound 141_1 is organically modified. It is preferable that the LUMO level is higher than that of compound 141_2. Alternatively, organic compound 141_ If 2 has hole transport properties and organic compound 141_1 has electron transport properties, then organic compound 1 It is preferable that the HOMO level of 41_2 is higher than the HOMO level of organic compound 141_1. The LUMO level of organic compound 141_2 is higher than that of organic compound 141_1. This is preferable. Specifically, the HOMO level of organic compound 141_1 and organic compound 141 The energy difference with the HOMO level of _2 is preferably 0.05 eV or more, and more preferably The voltage is 0.1 eV or higher, and more preferably 0.2 eV or higher. The energy difference between the LUMO level of substance 141_1 and the LUMO level of organic compound 141_2 is Preferably 0.05 eV or higher, more preferably 0.1 eV or higher, and even more preferably The voltage is 0.2 eV or higher.

[0219] Furthermore, the combination of organic compound 141_1 and organic compound 141_2 exhibits hole transport properties. In the case of a combination of a compound that possesses electron transport properties and a compound that has electron transport properties, the mixing ratio of the two compounds... This makes it possible to easily control the carrier balance. Specifically, it has hole transport properties. Compounds: Compounds with electron transport properties = preferably in the range of 1:9 to 9:1 (by weight). Furthermore, having this configuration makes it easy to control the career balance. Furthermore, the carrier recombination region can be easily controlled.

[0220] <Energy transfer mechanism> Next, the control of the intermolecular energy transfer process between the host material 141 and the guest material 142. Let's explain the factors. The mechanism of energy transfer between molecules is the Förster mechanism (bi Two mechanisms have been proposed: the polar-dipole interaction and the Dexter mechanism (electron exchange interaction). Here, the intermolecular energy transfer between the host material 141 and the guest material 142 is described. The process will be explained below, and the same applies when the host material 141 is an excited complex.

[0221] ≪Förster mechanism≫ In the Förster mechanism, energy transfer does not require direct contact between molecules, and the host Energy transfer occurs through the resonance phenomenon of dipole vibrations between material 141 and guest material 142. This is due to the resonance phenomenon of dipole oscillation, which transfers energy from the host material 141 to the guest material 142. The excited host material 141 returns to the ground state, and the guest material 14 returns to the ground state. 2 enters an excited state. Note that the rate constant k of the Förster mechanism is... h*→g This is shown in equation (1). .

[0222]

number

[0223] In equation (1), ν represents the frequency, and f' h (ν) is a standard for host material 141. Emission spectra (when discussing energy transfer from singlet excited states, fluorescence spectra are used) When discussing energy transfer from a triplet excited state, the phosphorescence spectrum) is represented, ε g (ν) represents the molar absorption coefficient of the guest material 142, N represents Avogadro's number, and n represents the refractive index of the medium, R represents the intermolecular distance between the host material 141 and the guest material 142 and τ represents the measured lifetime of the excited state (fluorescence lifetime or phosphorescence lifetime), c represents the speed of light , φ represents the luminescence quantum yield (fluorescence quantum yield when discussing energy transfer from a singlet excited state, phosphorescence quantum yield when discussing energy transfer from a triplet excited state), and K represents 2 is , a coefficient (0 to 4) representing the orientation of the transition dipole moments of the host material 141 and the guest material 142. In the case of random orientation, K 2 = 2 / 3.

[0224] ≪Dexter mechanism≫ In the Dexter mechanism, the host material 141 and the guest material 142 approach the contact effective distance where orbital overlap occurs, and energy transfer occurs through the exchange of electrons between the electrons of the excited state host material 141 and the ground state guest material 14 2. The rate constant k of the Dexter mechanism is shown in Equation (2). h*→g is shown in Equation (2).

[0225]

Equation

[0226] In Equation (2), h is Planck's constant, K is a constant with the dimension of energy and ν represents the frequency, and f’ h (ν) is the normalized emission spectrum of the host material 141 (fluorescence spectrum when discussing energy transfer from a singlet excited state, triplet when discussing energy transfer from a triplet excited state, phosphorescence spectrum), When discussing energy transfer from an excited state, it is represented by the phosphorescence spectrum), and ε’ g (ν) represents the normalized absorption spectrum of the guest material 142, L represents the effective molecular radius, and R represents the intermolecular distance between the host material 141 and the guest material 142.

[0227] Here, the energy transfer efficiency φ ET from the host material 141 to the guest material 142 is expressed by Equation (3). k r is the emission process of the host material 141 (fluorescence when discussing energy transfer from the singlet excited state, phosphorescence when discussing energy transfer from the triplet excited state) represents the rate constant, and k n is the non-emission process (thermal deactivation or intersystem crossing) of the host material 141 and represents the rate constant, and τ represents the measured lifetime of the excited state of the host material 141.

[0228]

Equation

[0229] From Equation (3), to increase the energy transfer efficiency φ ET , it can be seen that the rate constant k of energy transfer should be increased, and the other competing rate constants k h*→g + k r + k n (= 1 / τ) should be relatively small.

[0230] ≪Concepts for enhancing energy transfer≫ In energy transfer by the Förster mechanism, the energy transfer efficiency φ ET is preferably higher when the emission quantum yield φ (fluorescence quantum yield when discussing energy transfer from the singlet excited state, phosphorescence quantum yield when discussing energy transfer from the triplet excited state) is high. Also Furthermore, the emission spectrum of host material 141 (to discuss energy transfer from singlet excited state) (In this case, fluorescence spectrum) and absorption spectrum of guest material 142 (from singlet ground state to triple It is preferable that there is a large overlap with the absorption corresponding to the transition to the excited state. It is preferable that the molar extinction coefficient of the host material 142 is also high. This is because the light emission of the host material 141 This means that the spectrum and the absorption band that appears at the longest wavelength end of guest material 142 overlap. ru.

[0231] Furthermore, in energy transfer by the Dexter mechanism, the rate constant k h*→g Make it bigger To do this, we need to consider the emission spectrum of the host material 141 (to discuss energy transfer from the singlet excited state). When discussing the fluorescence spectrum, use the fluorescence spectrum; when discussing energy transfer from the triplet excited state, use the phosphorescence spectrum. Absorption spectra of the culvert and guest material 142 (from singlet ground state to triplet excited state) A larger overlap with the absorption corresponding to the transition is desirable. Therefore, the energy transfer efficiency The optimization involves comparing the emission spectrum of the host material 141 with that of the guest material 142 at the longest wavelength end. This is achieved by the overlap of the absorption bands.

[0232] Furthermore, similar to the energy transfer from host material 141 to guest material 142, the excited complex The energy transfer process from to guest material 142 is also related to the Förster mechanism and the Deck Energy transfer occurs through both mechanisms in the star mechanism.

[0233] In other words, the host material 141 is capable of efficiently transferring energy to the guest material 142. 14 organic compounds that form an excited complex that functions as an energy donor. It has 1_1 and organic compound 141_2. Organic compound 141_1 and organic compound 1 The excited complexes formed by 41_2 are organic compound 141_1 and organic compound 141_2 in their elemental form. It becomes possible to form it at an excitation energy lower than the excited state. Therefore, the driving power of the light-emitting element The pressure can be reduced.

[0234] Furthermore, the T of guest material 142, which acts as an energy acceptor from the S1 level of the excited complex. To facilitate energy transfer to level 1, the emission spectrum of the excited complex and the It is preferable that the absorption band appearing on the longest wavelength side (lowest energy side) of material 142 overlaps with the other band. By doing so, we can increase the efficiency of generating the triplet excited state of guest material 142. ru.

[0235] Furthermore, the excited complex generated in the light-emitting layer 140 consists of singlet excitation energy levels and triplet Because it has the characteristic of having the excitation energy level in close proximity, the emission spectrum of the excited complex By overlapping the absorption bands that appear on the longest wavelength side (lowest energy side) of the guest material 142, From the triplet excitation energy level of the excited complex to the triplet excitation energy level of guest material 142 This also makes it easier for energy to transfer to other positions.

[0236] By configuring the light-emitting layer 140 as described above, the guest material 142 (phosphorized) of the light-emitting layer 140 This makes it possible to efficiently obtain light emission from the combined material.

[0237] Furthermore, the processes of routes E7 to E9 shown above are referred to as ExTET(Ex in this specification, etc.). It is sometimes referred to as ciplex-triplet energy transfer. In other words, the light-emitting layer 140 provides the excitation energy from the excited complex to the guest material 142. There is a provision. Note that in this case, it is not necessarily T PE From S PE The reverse interterm crossing efficiency needs to be high. No, S PE Since a high emission quantum yield is not required, a wide range of materials can be selected. It becomes possible.

[0238] Furthermore, the light-emitting layer 170 has the same configuration as the light-emitting layer 130 shown in Embodiment 1, and the same configuration as the light-emitting layer 140. It can have a configuration.

[0239] In each of the above configurations, the light-emitting unit 106 and the light-emitting unit 108, or the light-emitting unit The luminescence color exhibited by the guest material used in unit 106 and light-emitting unit 110 is as follows: They may be the same or different from each other. (Light-emitting unit 106 and light-emitting unit 108) , or a device in which light-emitting unit 106 and light-emitting unit 110 emit light of the same color from each other. When a guest material with the ability is present, the light-emitting element 250 and light-emitting element 252 have a low current value This is preferable as it results in a light-emitting element that exhibits high luminous brightness. Also, the light-emitting unit 106 and the light-emitting element Knit 108, or light-emitting unit 106 and light-emitting unit 110, are of different colors from each other. If a guest material having the function of emitting light is present, light-emitting element 250 and light-emitting element 252 This is preferable as a light-emitting element that exhibits multicolor light emission. In this case, the light-emitting layer 120 and the light-emitting layer 170 Either one or both of the light-emitting layer 140 and light-emitting layer 170 if By using multiple light-emitting materials with different emission wavelengths in both the light-emitting element 250 and The emission spectrum exhibited by the light-emitting element 252 was a composite of emissions with different emission peaks. Since it becomes light, it will have an emission spectrum with at least two maximum values.

[0240] The above configuration is also suitable for obtaining white light emission. The light-emitting layer 120 and the light-emitting layer 170, Alternatively, by making the light from the light-emitting layer 140 and the light-emitting layer 170 complementary colors to each other, white light is produced. Light emission can be obtained. In particular, white light with high color rendering, or at least red and green light. It is preferable to select guest materials such that the emission has both a blue and a light-colored component.

[0241] Furthermore, at least one of the light-emitting layer 120, light-emitting layer 140, or light-emitting layer 170 is arranged in layers. It may be further divided into layers, and each divided layer may contain a different light-emitting material. Furthermore, at least one of the light-emitting layers 120, 140, or 170 is two or more layers. It can also be constructed with multiple layers. For example, the first light-emitting layer and the second light-emitting layer can be used for hole transport. When stacking layers sequentially from the layer side to form an emissive layer, the host material of the first emissive layer has hole transport properties. Using a material that possesses electron transport properties, the host material for the second light-emitting layer is a structure that uses such a material. Examples include the formation. In this case, the light-emitting material of the first light-emitting layer and the second light-emitting layer is the same material. Even if they are present, they may be made of different materials, or materials that have the function of emitting light of the same color. The materials may also have the function of emitting light of different colors. A configuration having multiple light-emitting materials that have the function of producing the three primary colors or four or more light-emitting colors It is also possible to obtain white light emission with high color rendering.

[0242] <Example of light-emitting element configuration 3> Next, Figures 8(A)(B)(C) show examples of configurations different from the light-emitting elements shown in Figures 6 and 7. The following explanation will be given using [this method].

[0243] Figure 8(A) is a schematic cross-sectional view of the light-emitting element 254.

[0244] The light-emitting element 254 shown in Figure 8(A) has a pair of electrodes (electrode 101 and electrode 102) between them. The structure has an EL layer 100 sandwiched in between. In the light-emitting element 254, the electrode 101 is the anode. Assuming that it functions as such, and that electrode 102 functions as the cathode, the following explanation will be given, but the light-emitting element 25 The configuration of 4 can also be reversed.

[0245] Furthermore, the EL layer 100 has a light-emitting layer 180, and the light-emitting layer 180 is made of light-emitting layer 120 and It has a layer 140 and, in addition, in the light-emitting element 254, the EL layer 100 is the light-emitting layer In addition, there is a hole injection layer 111, a hole transport layer 112, an electron transport layer 118, and an electron injection layer 119. Although these are illustrated, these stacked structures are just examples, and the EL layer 1 in the light-emitting element 254 The configuration of 00 is not limited to these. For example, in the EL layer 100, the stacking order of each layer may vary. This may be changed. Alternatively, functional layers other than those mentioned above may be provided in the EL layer 100. The functional layer may, for example, have a function to reduce the hole or electron injection barrier, or a function to reduce the hole or electron injection barrier. Functions that improve the transportability of holes or electrons, functions that inhibit the transportability of holes or electrons The configuration may have functions that occur.

[0246] Furthermore, as shown in Figure 8(B), the light-emitting layer 120 consists of a host material 121 and a guest material 1 It has 22. The light-emitting layer 140 also has a host material 141 and a guest material 142. The host material 141 has organic compound 141_1 and organic compound 141_2. Furthermore, guest material 122 is a fluorescent compound, and guest material 142 is a phosphorescent compound. I will explain below.

[0247] Furthermore, at least one of the light-emitting layer 120 or the light-emitting layer 140 is as shown in Embodiment 1. It is preferable that the optical layer 130 has a specific configuration.

[0248] ≪Light-emitting mechanism of light-emitting layer 180≫ The light-emitting mechanism of the light-emitting layer 120 is the same as that of the light-emitting layer 120 shown in Figures 6(B) and 6(C). This is the mechanism. Furthermore, the light emission mechanism of the light-emitting layer 140 is as shown in Figure 7(B)(C) of the light-emitting layer 1 It uses the same light-emitting mechanism as the 40.

[0249] As shown in Figure 8(A), the luminescent layer 120 and the luminescent layer 140 are in contact with each other. In this case, at the interface between the light-emitting layer 120 and the light-emitting layer 140, the excited complex of the light-emitting layer 140 emits Energy transfer from the photolayer 120 to the host material 121 (especially the triplet excitation energy) Even if energy transfer occurs, the triplet excitation energy is converted into light in the light-emitting layer 120. It can be converted.

[0250] Furthermore, the T1 level of the host material 121 of the light-emitting layer 120 is the organic compound of the light-emitting layer 140. It is preferable that the T1 level is lower than that of substance 141_1 and organic compound 141_2. At 120, the S1 level of the host material 121 is the same as the S level of the guest material 122 (fluorescent compound). The T1 level is higher than level 1, and the T1 level of the host material 121 is higher than that of the guest material 122 (fluorescent compound). It is preferable that the level is lower than the T1 level of the substance.

[0251] Specifically, when TTA is used for the light-emitting layer 120 and ExTET is used for the light-emitting layer 140: The correlation of energy levels is shown in Figure 8(C). Note that the notation and symbols in Figure 8(C) are as follows: It is as follows: • Fluorescence EML (120): Emitting layer 120 (fluorescent layer) • Phosphorescence EML (140): Emitting layer 140 (Phosphorescent luminescence layer) • Host(121): Host material 121 • Guest (122): Guest material 122 (fluorescent compound) ·Host(141_1): Host material (organic compound 141_1) • Guest (142): Guest material 142 (phosphorescent compound) • Exciplex: Excited complex (organic compound 141_1 and organic compound 141_2) ·S FH : S1 level of host material 121 ·T FH :T1 level of host material 121 ·S FG : S1 level of guest material 122 (fluorescent compound) ·T FG : T1 level of guest material 122 (fluorescent compound) ·S PH : S1 level of host material (organic compound 141_1) ·T PH : T1 level of host material (organic compound 141_1) ·T PG : T1 level of guest material 142 (phosphorescent compound) ·S E : S1 level of the excited complex ·T E : T1 level of the excited complex

[0252] As shown in Figure 8(C), since the excited complex exists only in the excited state, the excited complex and the excited Exciton diffusion between the complex and the excited complex is unlikely to occur. Also, the excitation energy level (S) of the excited complex E , T E ) is the organic compound 141_1 of the light-emitting layer 140 (i.e., the host material of the phosphorescent compound) Excitation energy level (S PH , T PH Since it is lower than ), the excited complex is converted to organic compound 14 No energy diffusion to 1_1 occurs. That is, within the phosphorescent emitting layer (emitting layer 140) Therefore, because the exciton diffusion distance of the excited complex is short, the efficiency of the phosphorescent layer (luminescent layer 140) is maintained. This becomes possible. Also, the fluorescent emitting layer (emitting layer 120) and the phosphorescent emitting layer (emitting layer 140) At the interface, a portion of the triplet excitation energy of the excited complex of the phosphorescent layer (luminescent layer 140) Even if it diffuses into the fluorescent emission layer (emission layer 120), the fluorescent emission layer produced by that diffusion The triplet excitation energy of the (emissive layer 120) is converted into light through TTA, therefore, This makes it possible to reduce energy loss.

[0253] As described above, the light-emitting element 254 uses ExTET in the light-emitting layer 140, and the light-emitting layer 1 By using TTA in step 20, energy loss is reduced, resulting in highly efficient emission. It can be made into an element. Also, as shown in the light-emitting element 254, the light-emitting layer 120 and the light-emitting layer When 140 and the other are in contact with each other, the above energy loss is reduced, and E The number of layers in the L layer 100 can be reduced. Therefore, the manufacturing cost of the light-emitting element is lower. It can be done this way.

[0254] Furthermore, the light-emitting layer 120 and the light-emitting layer 140 may not be in contact with each other. In this case, organic compound 141_1, organic compound 141_2, and are generated in the light-emitting layer 140. From the excited state of guest material 142 (phosphorescent compound) to host material 121 in emissive layer 120 , or energy transfer to guest material 122 (fluorescent compound) via the Dexter mechanism ( In particular, triplet energy transfer can be prevented. Therefore, the light-emitting layer 120 and the light-emitting layer 1 The layer between layer 40 and layer 40 only needs to be a few nanometers thick. Specifically, 1 nm to 5 nm thick. The following conditions are preferable because they can suppress the rise in drive voltage.

[0255] The layer provided between the light-emitting layer 120 and the light-emitting layer 140 may be made of a single material. It may contain both hole-transporting and electron-transporting materials. It may be composed of a single material. In some cases, bipolar materials may be used. Here, a bipolar material is defined as a material with electrons and holes. This refers to materials in which the ratio of the mobility of holes to electrons is 100 or less. It also refers to hole-transporting materials or electron-transporting materials. You may use materials such as phosphors. Alternatively, at least one of them may be phosphors of the light-emitting layer 140. Even if formed with the same material as the material (organic compound 141_1 or organic compound 141_2) Good. This makes it easier to fabricate light-emitting elements and reduces the driving voltage. Furthermore, Alternatively, an excitation complex may be formed with a hole transport material and an electron transport material, thereby exciton This effectively prevents the diffusion of the host material (organic compound) of the light-emitting layer 140. Substance 141_1 or organic compound 141_2) or guest material 142 (phosphorescent compound) From the excited state, the host material 121 or guest material 122 of the light-emitting layer 120 (fluorescence) This prevents energy transfer to the combined substance.

[0256] Furthermore, in the light-emitting element 254, the light-emitting layer 120 is on the hole transport layer 112 side, and the light-emitting layer 140 Although this was described as the electron transport layer 118 side, the light-emitting element in one aspect of the present invention is not limited to this. It is not determined, and the light-emitting layer 120 is on the electron transport layer 118 side, and the light-emitting layer 140 is on the hole transport layer 112 side. That's fine.

[0257] Furthermore, in the light-emitting element 254, the carrier recombination region is formed with a certain degree of distribution. It is preferable that the light-emitting layer 120 or light-emitting layer 140 has an appropriate amount of carrier It is preferable that the guest material 142 (phosphorized) of the light-emitting layer 140 It is preferable that the compound has electron trapping properties. Alternatively, the light-emitting layer 120 has It is preferable that the trapping material 122 (fluorescent compound) has hole-trapping properties.

[0258] Furthermore, the emission from the light-emitting layer 120 has a shorter wavelength peak than the emission from the light-emitting layer 140. It is preferable to have a configuration that has a . Optical elements tend to degrade in brightness quickly. Therefore, by using fluorescence emission for short-wavelength emission... This makes it possible to provide a light-emitting element with minimal brightness degradation.

[0259] Furthermore, by obtaining light of different emission wavelengths from the light-emitting layer 120 and the light-emitting layer 140, multicolor It can be used as a light-emitting element. In this case, the emission spectrum will have different emission peaks. Since the emitted light is a composite of light, the emission spectrum will have at least two maxima. .

[0260] Furthermore, the above configuration is also suitable for obtaining white light emission. Light-emitting layer 120 and light-emitting layer 140 By making the light and the light complementary to each other, white light emission can be obtained.

[0261] Furthermore, either one or both of the light-emitting layers 120 and 140 have different emission wavelengths. By using multiple light-emitting materials, high color rendering can be achieved using the three primary colors or four or more light-emitting colors. It is also possible to obtain white light emission. In this case, the light-emitting layer is further divided into layers, and the divided Each layer may contain a different luminescent material.

[0262] <Examples of materials that can be used for the light-emitting layer> Next, regarding materials that can be used for the light-emitting layer 120, light-emitting layer 140, and light-emitting layer 170... I will explain below.

[0263] <<Materials that can be used for the light-emitting layer 120>> In the light-emitting layer 120, the host material 121 is the most abundant by weight, followed by the guest material 122 The (fluorescent compound) is dispersed in the host material 121. The S1 level of the host material 121 is The S1 level of guest material 122 (fluorescent compound) is higher than the T1 level of host material 121. The level is preferably lower than the T1 level of guest material 122 (fluorescent compound).

[0264] In the light-emitting layer 120, there are no particular limitations on the guest material 122, but anthracene is also acceptable. Derivatives, tetracene derivatives, chrysene derivatives, phenanthrene derivatives, pyrene derivatives, Lylene derivatives, stilbene derivatives, acridone derivatives, coumarin derivatives, phenoxazine Derivatives, phenothiazine derivatives, etc., are preferred. Specifically, for example, as shown in Embodiment 1. The fluorescent compounds exemplified above can be used as guest material 132.

[0265] Furthermore, in the light-emitting layer 120, the materials that can be used for the host material 121 are: There are no particular limitations, but for example, tris(8-quinolinolato)aluminum(III) (abbreviation) :Alq), Tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviation: Almq3), bis(10-hydroxybenzo[h]quinolinato)beryllium(II) Abbreviation: BeBq2), bis(2-methyl-8-quinolinolate)(4-phenylphenolate ) Aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (Abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolate]zinc(II) Abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolate]zinc(II) Metal complexes such as (abbreviated as ZnBTZ), 2-(4-biphenylyl)-5-(4-tert- Butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5 -(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]ben Zen (abbreviation: OXD-7), 3-(4-biphenylyl)-4-phenyl-5-(4-te rt-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 2,2',2' -(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzoimidazo Vasophenanthroline (abbreviation: TPBI), Vasophenanthroline (abbreviation: BPhen), Vasocuproline (Abbreviation: BCP), 9-[4-(5-phenyl-1,3,4-oxadiazole-2- Heterocyclic compounds such as yl(phenyl)-9H-carbazole (abbreviation: CO11), 4,4 '-Bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) (α-NPD), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1 ,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N-( Spiro-9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation) Examples include aromatic amine compounds such as BSPB. Also, anthracene derivatives, ferrous compounds, etc. Nanthrene derivatives, pyrene derivatives, chrysene derivatives, dibenzo[g,p]chrysene derivatives Examples include condensed polycyclic aromatic compounds such as 9,10-diphenylanthracene (Abbreviation: DPAnth), N,N-diphenyl-9-[4-(10-phenyl-9-Anth) Tolyl)phenyl]-9H-carbazole-3-amine (abbreviation: CzA1PA), 4-( 10-phenyl-9-anthryl)triphenylamine (abbreviation: DPhPA), 4-(9 H-carbazole-9-yl)-4'-(10-phenyl-9-anthryl)triphenyl Luamine (abbreviation: YGAPA), N,9-diphenyl-N-[4-(10-phenyl-9 -Anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: PCAPA), N ,9-diphenyl-N-{4-[4-(10-phenyl-9-antryl)phenyl]f phenyl-9H-carbazole-3-amine (abbreviation: PCAPBA), N,9-diphenyl ru-N-(9,10-diphenyl-2-anthryl)-9H-carbazole-3-amine (Abbreviation: 2PCAPA), 6,12-dimethoxy-5,11-diphenylchrysene, N, N,N',N',N'',N'',N''',N'''-Octaphenyldibenzo[g, p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), 9-[4-(1 O-phenyl-9-antryl)phenyl]-9H-carbazole (abbreviation: CzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-antryl)phenyl]-9H -Carbazole (abbreviation: DPCzPA), 9,10-bis(3,5-diphenylphenyl )Anthracene (abbreviation: DPPA), 9,10-di(2-naphthyl)anthracene (abbreviation :DNA), 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation) :t-BuDNA), 9,9'-biantril (abbreviation: BANT), 9,9'-(still Ben-3,3'-diphenylenanthren (abbreviation: DPNS), 9,9'-(Stilbe n-4,4'-diyl)diphenanthrene (abbreviation: DPNS2), 1,1',1''-( Examples include benzene-1,3,5-triyl)tripylene (abbreviation: TPB3). It is possible. Also, from among these and known substances, the energy gap of the above guest material 122 If you select and use one or more materials that have a larger energy gap than P good.

[0266] The light-emitting layer 120 can also be composed of two or more layers. For example, the first When the first light-emitting layer and the second light-emitting layer are stacked in order from the hole transport layer side to form the light-emitting layer 120, A material having hole transport properties is used as the host material for the first light-emitting layer, and the host material for the second light-emitting layer One such configuration involves using materials that possess electron-transporting properties.

[0267] Furthermore, in the light-emitting layer 120, the host material 121 is composed of a certain compound. It is also fine if it is composed of multiple compounds. Alternatively, in the light-emitting layer 120, It may also contain materials other than stock material 121 and guest material 122.

[0268] Furthermore, the light-emitting layer 120 may have the same configuration as the light-emitting layer 130 shown in Embodiment 1. In this case, the host material 131 and guest material 132 (fluorescent compound) shown in Embodiment 1 It is preferable to use [this].

[0269] <<Materials that can be used for the light-emitting layer 140>> In the light-emitting layer 140, the host material 141 is the most abundant by weight, followed by the guest material 142 The (phosphorescent compound) is dispersed in the host material 141. Host material 14 of the luminescent layer 140 The T1 level of 1 (organic compound 141_1 and organic compound 141_2) is that of guest material 142 It is preferable that the level is higher than the T1 level.

[0270] Organic compound 141_1 includes zinc and aluminum-based metal complexes, as well as oxadiazo Diazepam derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, diazepam Dibenzoquinoxaline derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, pyrimidin phenanthroline derivatives, triazine derivatives, pyridine derivatives, bipyridine derivatives, phenanthroline derivatives Examples include conductors. Other examples include aromatic amines and carbazole derivatives. Specifically, using the electron-transporting material and hole-transporting material shown in Embodiment 1, It is possible.

[0271] Organic compound 141_2 is a combination that can form an excited complex with organic compound 141_1. A combination is preferable. Specifically, for example, the electron transport material and hole shown in Embodiment 1. Transportable materials can be used. In this case, organic compound 141_1 and organic compound 141 The emission peak of the excited complex formed with _2 is the triple emission peak of guest material 142 (phosphorescent compound). Term MLCT (Metal to Ligand Charge Transfer) transition The absorption band, more specifically, the absorption band on the longest wavelength side, is overlapped with that of organic compound 141_ 1. Select organic compounds 141_2 and guest material 142 (phosphorescent compound). This is preferable. This makes it possible to create a light-emitting element with dramatically improved luminous efficiency. However, Furthermore, when using a thermally activated delayed fluorescence compound instead of a phosphorescent compound, the longest wavelength The absorption band on the longer side is preferably a singlet absorption band.

[0272] Guest material 142 (phosphorescent compound) can be iridium, rhodium, or platinum-based. Examples include organometallic complexes or metal complexes, among which organoiridium complexes, for example, iridium Um-based orthometallic complexes are preferred. 4H-triazo is a suitable ligand for orthometallation. 1H-triazole ligand, 1H-triazole ligand, imidazole ligand, pyridine ligand, pyrimi Examples include din ligands, pyrazine ligands, or isoquinoline ligands. Metal complexes Examples include platinum complexes having porphyrin ligands. Specifically, for example... Furthermore, the phosphorescent compound exemplified as the guest material 132 shown in Embodiment 1 can be used. Cut.

[0273] The light-emitting material included in the light-emitting layer 140 is capable of converting triplet excitation energy into light emission. Any material will do. A material that can convert the triplet excitation energy into light emission is phosphorescent. In addition to compound compounds, thermally activated delayed fluorescence compounds are also mentioned. Therefore, they are described as phosphorescent compounds. The part indicated can be interpreted as a thermally activated delayed fluorescence compound.

[0274] Furthermore, materials exhibiting thermally activated delayed fluorescence can be subjected to reverse intersystem crossing from a triplet excited state. It may be a material that can generate a multiplet excited state, or an excited complex (excyplex, also It may be composed of multiple materials that form an Exciplex (also known as an Exciplex).

[0275] When a thermally activated delayed fluorescence compound is composed of a single material, specifically, the implementation The thermally activated delayed fluorescence compound shown in Form 1 can be used.

[0276] Furthermore, when a thermally activated delayed fluorescence compound is used as a host material, an excited complex is formed. It is preferable to use a combination of two types of compounds. In this case, the excitation complex shown above is used. Compounds that readily accept electrons and compounds that readily accept holes are combinations that form a pair It is especially preferable to use objects.

[0277] Furthermore, the light-emitting layer 140 may have the same configuration as the light-emitting layer 130 shown in Embodiment 1. In this case, the host material 131 and guest material 132 (phosphorescent compound) shown in Embodiment 1 It is preferable to use [this].

[0278] <<Materials that can be used for the light-emitting layer 170>> Materials that can be used for the light-emitting layer 170 include those used for the light-emitting layer shown in Embodiment 1 above. By using materials that can be used, it is possible to create light-emitting elements with high luminescence efficiency. It can be manufactured.

[0279] Furthermore, the emission color of the light-emitting material contained in the light-emitting layer 120, light-emitting layer 140, and light-emitting layer 170 There are no limitations; they can be the same or different. The light emitted from each is mixed. Since it is extracted outside the element, for example, if the light emitted by both is complementary to each other, the light-emitting element The child can emit white light. Considering the reliability of the light-emitting element, the light-emitting layer 120 is included The emission peak wavelength of the light-emitting material is shorter than that of the light-emitting material contained in the light-emitting layer 170. This is preferable.

[0280] Furthermore, the light-emitting unit 106, light-emitting unit 108, light-emitting unit 110, and charge generation Layer 115 can be produced using methods such as vapor deposition (including vacuum deposition), inkjet printing, coating, and gravure printing. It can be formed by the following method.

[0281] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments. It is possible to be there.

[0282] (Embodiment 3) In this embodiment, the light-emitting element has a configuration different from that shown in Embodiments 1 and 2. An example of this will be explained below using Figures 9 to 12.

[0283] <Example of light-emitting element configuration 1> Figures 9(A) and 9(B) are cross-sectional views showing a light-emitting element according to one embodiment of the present invention. In (B), the same hatching is used in areas that have the same function as the symbols shown in Figure 1(A). In some cases, the code may be omitted as a pattern. Also, similar functions are used in similar places. Symbols may be used, and detailed explanations may be omitted.

[0284] The light-emitting elements 260a and 260b shown in Figures 9(A) and 9(B) are connected to the substrate 200 side. It may also be a bottom-emission type light-emitting element that extracts from the substrate 200 and It may also be a top-emission type light-emitting element that extracts light in the opposite direction. However, one aspect of the present invention is not limited thereto, and the light emitted by the light-emitting element is directed upwards on the substrate 200. It may also be a dual-emission type light-emitting element that emits light from both the upper and lower sides. .

[0285] When the light-emitting element 260a and light-emitting element 260b are of the bottom emission type, electrode 1 Preferably, 01 has the function of transmitting light. Also, electrode 102 reflects light. It is preferable that the light-emitting element 260a and the light-emitting element 260b have a function. In the case of a top-emission type, it is preferable that the electrode 101 has the function of reflecting light. Furthermore, it is preferable that the electrode 102 has the function of transmitting light.

[0286] The light-emitting element 260a and the light-emitting element 260b have an electrode 101 and an electrode 102 on the substrate 200. It has the following: In addition, between electrode 101 and electrode 102, there is a light-emitting layer 123B and a light-emitting layer 123 It has G and a light-emitting layer 123R. It also has a hole injection layer 111 and a hole transport layer 112. It has an electron transport layer 113 and an electron injection layer 114.

[0287] Furthermore, the light-emitting element 260b is part of the configuration of the electrode 101, and the conductive layer 101a and the conductive It has a conductive layer 101b on layer 101a and a conductive layer 101c below the conductive layer 101a. In other words, the light-emitting element 260b has a conductive layer 101a, a conductive layer 101b, and a conductive layer 101c. It has a configuration of clamped electrodes 101.

[0288] In the light-emitting element 260b, the conductive layer 101b and the conductive layer 101c are made of different materials. They may be made of the same material. Conductive layer 101b and conductive layer 101c are When formed from the same conductive material, the etching process in the formation process of the electrode 101 This is preferable because it facilitates pattern formation.

[0289] Furthermore, in the light-emitting element 260b, in the conductive layer 101b or the conductive layer 101c, A configuration having only one of the two offsets is also acceptable.

[0290] Furthermore, the conductive layers 101a, 101b, and 101c of the electrode 101 are each implemented The same configuration and materials as those used for electrode 101 or electrode 102 shown in Form 1 can be used. Cut.

[0291] In Figures 9(A)(B), the region 221B is sandwiched between electrode 101 and electrode 102. A partition wall 145 is located between region 221G and region 221R. The partition wall 145 provides insulation. The partition wall 145 covers the end of the electrode 101 and has an opening that overlaps with the electrode. By providing 145, the electrodes 101 on the substrate 200 in each region are separated into island-like structures. It becomes possible to separate them.

[0292] Furthermore, in the region where the light-emitting layer 123B and the light-emitting layer 123G overlap with the partition wall 145, It may have an overlapping region. Also, the light-emitting layer 123G and the light-emitting layer 123R are separated by a distance. In the region overlapping with wall 145, there may be overlapping regions with each other. Also, the light-emitting layer 1 23R and the light-emitting layer 123B overlap with the partition wall 145, and the overlapping regions of each other It is acceptable to have it.

[0293] The partition wall 145 only needs to be insulating and is formed using an inorganic or organic material. The inorganic materials include silicon oxide, silicon oxide nitride, silicon nitride oxide, silicon nitride silicon Examples of organic materials include aluminum oxide, aluminum nitride, etc. Examples include photosensitive resin materials such as acrylic resin or polyimide resin.

[0294] Furthermore, a silicon oxidizride film is a film whose composition contains more oxygen than nitrogen. Preferably, oxygen is 55 atomic% or more and 65 atomic% or less, and nitrogen is 1 atomic% or more and 20 atomic%. Below, silicon is 25 atomic% to 35 atomic%, and hydrogen is 0.1 atomic% to 10 atomic%. This refers to films that fall within the range below. A silicon nitride oxide film is a film whose composition contains more nitrogen than oxygen. This refers to a membrane with a high element content, preferably containing 55 atomic% or more and 65 atomic% or less of nitrogen, and 1 atomic% of oxygen. Atomic percent to 20 atomic percent, silicon 25 atomic percent to 35 atomic percent, hydrogen 0.1 atomic percent This refers to a film containing a substance in a concentration range of 10% to 10 atomic%.

[0295] Furthermore, the light-emitting layer 123R, light-emitting layer 123G, and light-emitting layer 123B each exhibit different colors. It is preferable to have a light-emitting material that has the function of emitting red light. For example, the light-emitting layer 123R exhibits red light. By having a light-emitting material that has the function of, region 221R exhibits red light emission, and light-emitting layer 12 Region 221G emits green light because region 3G has a light-emitting material that exhibits a green light. The light-emitting layer 123B has a light-emitting material that exhibits a blue color, thus region 221 B emits blue light. A light-emitting element 260a or light-emitting element 26 has such a configuration. By using 0b as the pixel of the display device, a display device capable of full-color display can be manufactured. This is possible. Also, the film thickness of each light-emitting layer may be the same or different. good.

[0296] Additionally, one or more of the light-emitting layers 123B, 123G, and 123R. The light-emitting layer preferably has the configuration of the light-emitting layer 130 shown in Embodiment 1. This makes it possible to fabricate light-emitting elements with good luminescence efficiency and high reliability. .

[0297] Note that one or more of the light-emitting layers 123B, 123G, and 123R may be present. The light-emitting layer may be configured with two or more layers stacked on top of each other.

[0298] As described above, at least one light-emitting layer has the configuration of the light-emitting layer shown in Embodiment 1, A light-emitting element 260a or light-emitting element 260b having the light-emitting layer is used as a pixel in a display device. This makes it possible to manufacture display devices with high luminous efficiency and high reliability. In other words, a display device having a light-emitting element 260a or a light-emitting element 260b reduces power consumption. It is possible.

[0299] Furthermore, in the direction from which light is extracted from the electrode that extracts light, an optical element (for example, a color filter) is placed. By providing polarizing plates, anti-reflective coatings, etc., the color purity of the light-emitting element 260a and the light-emitting element 260b is improved. The degree can be improved. Therefore, the light-emitting element 260a or light-emitting element 260b The color purity of the display device can be improved. Alternatively, the light-emitting element 260a and the light-emitting element can be improved. External light reflection of 260b can be reduced. Therefore, the light-emitting element 260a or light-emitting element The contrast ratio of a display device having sub-element 260b can be increased.

[0300] Furthermore, other configurations of the light-emitting element 260a and light-emitting element 260b are as follows: The configuration of the light-emitting element in Embodiment 1 and Embodiment 2 should be taken into consideration.

[0301] <Example of light-emitting element configuration 2> Next, Figure 10(A)(B) shows an example of a different configuration from the light-emitting element shown in Figures 9(A) and 9(B). The following explanation will be given using [this method].

[0302] Figures 10(A) and 10(B) are cross-sectional views showing a light-emitting element according to one embodiment of the present invention. In (A)(B), the parts that have the same function as the symbols shown in Figure 9(A)(B) are the same A hatch pattern is used, and the symbols may be omitted. Also, in places with similar functions... These are sometimes denoted by the same symbols, and their detailed explanations may be omitted.

[0303] Figures 10(A) and 10(B) show examples of the configuration of a light-emitting element having a light-emitting layer between a pair of electrodes. The light-emitting element 262a shown in 10(A) is an upper-surface emitter that extracts light in the direction opposite to the substrate 200. (Top emission) type light-emitting element, the light-emitting element 262b shown in Figure 10(B) is on substrate 2 This is a bottom-emission type light-emitting element that extracts light from the 00 side. One aspect of the invention, which is not limited thereto, is a substrate 20 on which the light-emitting element is formed, which emits light from the light-emitting element. It is also acceptable to use a dual-emission type that extracts from both above and below the 0. stomach.

[0304] The light-emitting element 262a and the light-emitting element 262b have an electrode 101 and an electrode 102 on the substrate 200. It has electrode 103 and electrode 104. Also, between electrode 101 and electrode 102, At least light is emitted between electrode 102 and electrode 103, and between electrode 102 and electrode 104. It has a layer 170, a light-emitting layer 190, and a charge-generating layer 115. It also has a hole injection layer 111 and , hole transport layer 112, electron transport layer 113, electron injection layer 114, hole injection layer 116 It has a hole transport layer 117, an electron transport layer 118, and an electron injection layer 119.

[0305] Furthermore, the electrode 101 consists of a conductive layer 101a and a conductive layer 101b that is in contact with the conductive layer 101a. , has . Furthermore, electrode 103 has a conductive layer 103a and a conductive layer in contact with the conductive layer 103a 103b and Electrode 104 has a conductive layer 104a and a conductive layer in contact with the conductive layer 104a. It has an electrolytic layer 104b.

[0306] The light-emitting element 262a shown in Figure 10(A) and the light-emitting element 262b shown in Figure 10(B) are, Region 222B sandwiched between electrode 101 and electrode 102, sandwiched between electrode 102 and electrode 103 Between the region 222G and the region 222R sandwiched between electrodes 102 and 104, It has a partition wall 145. The partition wall 145 is insulating. The partition wall 145 is an electrode 101, The partition wall 145 covers the ends of pole 103 and electrode 104 and has an opening that overlaps with the electrode. By providing this, the electrodes on the substrate 200 in each region can be separated into island-like structures. It becomes possible.

[0307] Furthermore, the charge generation layer 115 is made of a hole transport material to which electron acceptors are attached. By adding materials, or by adding electron donors to electron transport materials, It can be formed if the conductivity of the charge generation layer 115 is as high as that of the pair of electrodes. In addition, the carriers generated by the charge generation layer 115 flow to the adjacent pixels, and then to the adjacent pixels In some cases, the element may emit light unintentionally. Therefore, it is necessary to suppress the unauthorized emission of light from adjacent pixels. In order to achieve this, the charge generation layer 115 is formed of a material with lower conductivity than the pair of electrodes. preferable.

[0308] Furthermore, the light-emitting element 262a and the light-emitting element 262b are located in region 222B, region 222G, and In the direction from which the light emitted from region 222R is extracted, the optical element 224B and the optical element are respectively positioned. The substrate 220 has a sub-element 224G and an optical element 224R. Light emitted from each region It is emitted to the outside of the light-emitting element through each optical element. That is, it is emitted from region 222B. The light is emitted through the optical element 224B, and the light emitted from region 222G is emitted through the optical element The light emitted through 224G and emanating from region 222R is transmitted through optical element 224R. It is launched.

[0309] Furthermore, optical elements 224B, 224G, and 224R receive incident light It has the function of selectively transmitting light exhibiting a specific color. For example, optical element 224B The light emitted from region 222B through the optical element 22 becomes blue light. The light emitted from region 222G via 4G becomes green light, and the optical element The light emitted from region 222R via sub-element 224R is red in color.

[0310] Optical elements 224R, 224G, and 224B include, for example, a colored layer ( Color filters (also called color filters), bandpass filters, and multilayer filters can be applied. Furthermore, a color conversion element can be applied to an optical element. The color conversion element converts the incident light to... This is an optical element that converts light to wavelengths longer than the wavelength of the light in question. It uses quantum dots as color conversion elements. It is preferable to use an element that employs quantum dots. By using quantum dots, the color reproducibility of the display device can be improved. It can improve.

[0311] Furthermore, other optical elements may be placed on optical elements 224R, 224G, and 224B. One or more of these may be arranged in a stack. Other optical elements include, for example, circular polarizers and anti-reflective coatings. A protective film can be provided. The circular polarizing plate is used to extract light emitted from the light-emitting element of the display device. When placed on the receiving side, light incident from outside the display device is reflected inside the display device, and the outside This prevents the phenomenon of ejection from the part. In addition, by providing an anti-reflective coating, the surface of the display device This can reduce the amount of ambient light reflected by the device. This makes the light emitted by the display device clearer. It can be observed.

[0312] In Figures 10(A) and 10(B), the light emitted from each region through each optical element is... Let's define light as blue (B), light as green (G), and light as red (R), and each This is schematically illustrated with dashed arrows.

[0313] Furthermore, a light-shielding layer 223 is provided between each optical element. The light-shielding layer 223 is provided in adjacent regions or It has the function of blocking the light emitted from it. Furthermore, a configuration without the light-blocking layer 223 is also acceptable. stomach.

[0314] The light-shielding layer 223 has the function of suppressing the reflection of external light. Alternatively, the light-shielding layer 223 and Therefore, it has the function of preventing the mixing of colors of light emitted from adjacent light-emitting elements. Light-shielding layer 223 and For example, metals, resins containing black pigments, carbon black, metal oxides, and multiple metal oxides. A composite oxide containing a solid solution of a substance can be used.

[0315] Furthermore, in the region where optical element 224B and optical element 224G overlap with the light-shielding layer 223 They may have overlapping regions. Alternatively, optical element 224G and optical element 2 24R refers to a region that overlaps with the light-shielding layer 223, and may have overlapping regions with each other. Alternatively, optical element 224R and optical element 224B are in a region that overlaps with the light-shielding layer 223. In this context, it is acceptable for them to have overlapping regions.

[0316] Furthermore, the configuration of the substrate 200 and the substrate 220 having optical elements is as follows: Embodiment 1 You can take it into consideration.

[0317] Furthermore, the light-emitting elements 262a and 262b have a microcavity structure. .

[0318] <<Microcavity structure>> Light emitted from the light-emitting layer 170 and the light-emitting layer 190 is directed to a pair of electrodes (for example, electrode 10 Resonance occurs between 1 and electrode 102). Also, the light-emitting layer 170 and light-emitting layer 190 are emitted. It is formed at a position where the light of a desired wavelength is intensified among the incoming light. For example, in the reflection region of electrode 101 The optical distance from the light-emitting region of the light-emitting layer 170 to the optical distance from the reflection region of the electrode 102 to the light-emitting layer 170 By adjusting the optical distance to the light-emitting region, the light emitted from the light-emitting layer 170 can be controlled. This allows for the enhancement of light of a desired wavelength. Also, from the reflection region of electrode 101 to the light-emitting layer 190 The optical distance to the light-emitting region and the distance from the reflection region of electrode 102 to the light-emitting region of light-emitting layer 190. By adjusting the optical distance, the desired wavelength of light emitted from the light-emitting layer 190 can be selected. The light can be intensified. That is, multiple light-emitting layers (here, light-emitting layer 170 and light-emitting layer In the case of a light-emitting element that stacks 190), the optical distance between the light-emitting layer 170 and the light-emitting layer 190 is It is preferable to optimize the separation.

[0319] Furthermore, in the light-emitting element 262a and light-emitting element 262b, a conductive layer (conductive layer 1) is present in each region. By adjusting the thickness of 01b, conductive layer 103b, and conductive layer 104b), the light-emitting layer 170 Furthermore, it is possible to enhance the light of a desired wavelength from the light emitted from the light-emitting layer 190. In the region, at least one of the hole injection layer 111 or the hole transport layer 112, or electron injection By varying the thickness of at least one of the infill layer 119 or the electron transport layer 118, The light emitted from the light-emitting layer 170 and the light-emitting layer 190 may be intensified.

[0320] For example, electrodes 101 to 104 are made of a conductive material that has the function of reflecting light. When the refractive index is smaller than the refractive index of the light-emitting layer 170 or the light-emitting layer 190, the electrode The thickness of the conductive layer 101b on 101 is determined by the optical distance between electrode 101 and electrode 102 being m B λ B / 2(m B λ is a natural number, B (These represent the wavelengths of light that are strengthened in region 222B.) Adjust to achieve this. Similarly, the thickness of the conductive layer 103b on electrode 103 is adjusted to match electrode 103 and The optical distance between electrode 102 is m G λ G / 2(m G λ is a natural number, G Stronger in region 222G The wavelengths of light are adjusted to be (represented by). Furthermore, the conductive layer of electrode 104 The film thickness of 104b is such that the optical distance between electrode 104 and electrode 102 is m R λ R / 2(m R is natural number, λ R The wavelengths of light that are strengthened in region 222R are adjusted accordingly.

[0321] Furthermore, if it is difficult to precisely determine the reflection region of electrodes 101 to 104, By assuming that any region of electrode 101 to electrode 104 is a reflective region, the light-emitting layer 170 or The optical distance at which the light emitted from the light layer 190 is intensified may be derived. Also, the light-emitting layer 170 If it is difficult to precisely determine the light-emitting region of the light-emitting layer 190, the light-emitting layer 170 and By assuming that any region of the light layer 190 is an emission region, the emission layer 170 and the emission layer 190 You may also derive the optical distance at which the light emitted from the source is intensified.

[0322] As described above, a microcavity structure is provided, and the optical distance between the pair of electrodes in each region is adjusted. By optimizing the surface, light scattering and absorption near each electrode are suppressed, resulting in a high light extraction efficiency. It is possible to achieve this rate.

[0323] In the above configuration, conductive layer 101b, conductive layer 103b, and conductive layer 104b are light It is preferable that the conductive layer 101b, conductive layer 103b, and conductive The materials constituting layer 104b may be the same or different. When the same material is used for the electrical layer 101b, the conductive layer 103b, and the conductive layer 104b, electrode 10 1. Pattern formation by etching process during the formation of electrodes 103 and 104 is acceptable. This is preferable because it makes things easier. Also, conductive layers 101b, 103b, and 104b are Each layer may have a configuration consisting of two or more layers stacked on top of each other.

[0324] Furthermore, the light-emitting element 262a shown in Figure 10(A) is a top-export type light-emitting element, therefore it is conductive Layer 101a, conductive layer 103a, and conductive layer 104a have the function of reflecting light. Preferably, the electrode 102 has both the function of transmitting light and the function of reflecting light. It is preferable.

[0325] Furthermore, the light-emitting element 262b shown in Figure 10(B) is a bottom-export type light-emitting element, therefore The electrolytic layer 101a, conductive layer 103a, and conductive layer 104a have the function of transmitting light and reflecting light. It is preferable that the electrode 102 has the function of reflecting light. It is preferable.

[0326] Furthermore, in the light-emitting element 262a and light-emitting element 262b, conductive layer 101a, conductive layer 10 The same material may be used for 3a or the conductive layer 104a, or different materials may be used. When the same material is used for conductive layer 101a, conductive layer 103a, and conductive layer 104a, the light-emitting element The manufacturing costs of the sub-element 262a and the light-emitting element 262b can be reduced. The electrical layer 103a and the conductive layer 104a may each have a configuration in which two or more layers are stacked. stomach.

[0327] Furthermore, the light-emitting layer 170 or light-emitting layer 19 in the light-emitting element 262a and light-emitting element 262b At least one of 0 includes at least one of the configurations shown in Embodiment 1 and Embodiment 2. It is preferable to have one. By doing so, a light-emitting element that exhibits high luminous efficiency and high reliability It is possible to fabricate light-emitting devices that exhibit properties.

[0328] Furthermore, the light-emitting layer 170 and the light-emitting layer 190 are, for example, light-emitting layer 190a and light-emitting layer 190b Thus, a configuration in which two layers are stacked on one or both sides may be used. The two light-emitting layers include the first Two types of light-emitting materials, a compound and a second compound, which have the function of exhibiting different colors, are used. By using them, multiple light emission can be obtained simultaneously. In particular, the light emission layer 170 and the light emission layer Select the light-emitting material to be used in each light-emitting layer so that the light emitted by 190 results in a white color. And that is preferable.

[0329] Furthermore, the light-emitting layer 170 or the light-emitting layer 190 has a structure in which three or more layers are stacked, either one or both. It may be a composite material, and may also include a layer that does not contain luminescent material.

[0330] As described above, the configuration of the light-emitting layer shown in Embodiment 1 and Embodiment 2 is at least one By using the light-emitting element 262a or light-emitting element 262b as a pixel of a display device, It is possible to manufacture display devices with high optical efficiency and high reliability. A display device having an optical element 262a or a light-emitting element 262b can reduce power consumption. can.

[0331] Regarding the other configurations of the light-emitting element 262a and light-emitting element 262b, 260a or light-emitting element 260b, or the light-emitting elements shown in Embodiment 1 and Embodiment 2 You should consider the configuration of the optical element.

[0332] <Method for fabricating a light-emitting element> Next, a method for manufacturing a light-emitting element according to one embodiment of the present invention will be described below using Figures 11 and 12. An explanation will be given. Specifically, the method for fabricating the light-emitting element 262a shown in Figure 10(A) will be explained. explain.

[0333] Figures 11 and 12 are cross-sectional views illustrating a method for manufacturing a light-emitting element according to one embodiment of the present invention. be.

[0334] The method for fabricating the light-emitting element 262a described below comprises seven steps, from the first to the seventh. ru.

[0335] ≪Step 1≫ The first step is to create electrodes for the light-emitting element (specifically, conductive layers 101 that constitute the electrodes 101). a) conductive layer 103a constituting electrode 103, and conductive layer 104a constituting electrode 104) This is the process of forming it on the substrate 200 (see Figure 11(A)).

[0336] In this embodiment, a conductive layer having the function of reflecting light is formed on the substrate 200. By processing the conductive layer into a desired shape, conductive layer 101a, conductive layer 103a, and conductive Layer 104a is formed. The conductive layer having the function of reflecting light is made of silver and palladium. A copper alloy film (also called Ag-Pd-Cu film or APC) is used. The process of processing the same conductive layer to form the electrical layer 101a, conductive layer 103a, and conductive layer 104a. This method is preferable because it allows for lower manufacturing costs.

[0337] Note that before the first step, multiple transistors may be formed on the substrate 200. Furthermore, the plurality of transistors, conductive layer 101a, conductive layer 103a, and conductive layer 104a They may be electrically connected to each other.

[0338] ≪Step 2≫ The second step is to have a light-transmitting function on the conductive layer 101a that constitutes the electrode 101. A conductive layer 101b is placed on the conductive layer 103a constituting the electrode 103, and has the function of transmitting light. A conductive layer 103b is placed on the conductive layer 104a constituting the electrode 104, and has the function of transmitting light. This is the step of forming the conductive layer 104b (see Figure 11(B)).

[0339] In this embodiment, conductive layers 101a, 103a, and have the function of reflecting light, On 104a, there are conductive layers 101b, 103b, and respectively, which have the function of transmitting light. By forming 104b, electrodes 101, 103, and 104 are formed. ITSO films are used as the conductive layers 101b, 103b, and 104b.

[0340] Furthermore, the conductive layers 101b, 103b, and 104b, which have the function of transmitting light, can be used multiple times. It may be formed in stages. By forming it in stages, suitable microcaches can be formed in each region. The conductive layers 101b, 103b, and 104b can be formed with a film thickness that creates a vitreous structure. Cut.

[0341] ≪Step 3≫ The third step is to form partition walls 145 that cover the ends of each electrode of the light-emitting element. See Figure 11(C).

[0342] The partition wall 145 has an opening that overlaps with the electrode. The conductive film exposed by the opening. This functions as the anode of the light-emitting element. In this embodiment, the partition wall 145 is made of polyimide resin. Use fat.

[0343] Furthermore, in steps 1 to 3, the EL layer (the layer containing organic compounds) is damaged. Because there is no risk, various film formation methods and microfabrication techniques can be applied. This involves forming a reflective conductive layer using a sputtering method, and then using a lithography method to... A pattern is formed on the electrode layer, and then a dry etching method or a wet etching method is used. Then, by processing the conductive layer into an island shape, the conductive layer 101a and electrode 10 constitute the electrode 101. A conductive layer 103a constituting 3 and a conductive layer 104a constituting electrode 104 are formed. Subsequently, a transparent conductive film is deposited using the sputtering method, and then lithography is used. Then, a pattern is formed on the transparent conductive film, and then a wet etching method is used. Then, the transparent conductive film is processed into an island shape to form electrodes 101, 103, and 104. ru.

[0344] ≪Step 4≫ The fourth step involves a hole injection layer 111, a hole transport layer 112, a light-emitting layer 190, and an electron transport layer. This is a step to form 113, an electron injection layer 114, and a charge generation layer 115 (Figure 12(A)). reference).

[0345] As the hole injection layer 111, a material containing a hole transporting material and an acceptor material is vapor-deposited. It can be formed by deposition. Co-deposition is the process of depositing multiple different materials together. This is a vapor deposition method in which evaporation occurs simultaneously from an evaporation source. In addition, the hole transport layer 112 is a hole It can be formed by vapor deposition of a transportable material.

[0346] The light-emitting layer 190 can be purple, blue, blue-green, green, yellow-green, yellow, orange, or red. This is formed by depositing at least one luminescent guest material selected from among them. This can be done. As guest materials, luminescent organic compounds that exhibit fluorescence or phosphorescence are used. This is possible. Furthermore, by using the light-emitting layer configuration shown in Embodiment 1 and Embodiment 2 This is preferable. Alternatively, the light-emitting layer 190 may have a two-layer configuration. In that case, the two layers of light-emitting layer The light layer preferably contains luminescent organic compounds that exhibit different emission colors from each other. stomach.

[0347] The electron transport layer 113 can be formed by depositing a material with high electron transport properties. It is possible. Furthermore, the electron injection layer 114 is formed by depositing a material with high electron injection properties. It is possible.

[0348] As the charge generation layer 115, electron acceptors are added to a hole transport material. Deposition of a material, or a material to which an electron donor has been added to an electron transport material. It can be formed with.

[0349] ≪Step 5≫ The fifth step involves a hole injection layer 116, a hole transport layer 117, a light-emitting layer 170, and an electron transport layer. This is a step in which 118, the electron injection layer 119, and the electrode 102 are formed (see Figure 12(B)). .

[0350] The hole injection layer 116 is made of the same material and is made using the same method as the hole injection layer 111 described above. It can be formed more easily. Also, as the hole transport layer 117, the hole transport layer 11 shown above It can be formed using the same materials and methods as in 2.

[0351] The light-emitting layer 170 can be purple, blue, blue-green, green, yellow-green, yellow, orange, or red. By depositing at least one luminescent guest material selected from among them, the shape is formed. This can be achieved. As guest materials, luminescent organic compounds that exhibit fluorescence or phosphorescence can be used. It can be used. Also, the configuration of the light-emitting layer shown in Embodiment 1 and Embodiment 2 can be used. It is preferable that the light-emitting layer 170 and the light-emitting layer 190 exhibit different light emission from each other. It is preferable to have a luminescent organic compound that has the function of [details omitted].

[0352] The electron transport layer 118 is made of the same material and is constructed using the same method as the electron transport layer 113 described above. It can be formed more easily. Also, as the electron injection layer 119, the electron injection layer 11 shown above It can be formed using the same materials and methods as in 4.

[0353] The electrode 102 consists of a reflective conductive film and a translucent conductive film laminated together. It can be formed as follows. Also, the electrode 102 can be a single-layer structure or a multi-layer structure. That's good too.

[0354] After the above process, regions 222 are formed on electrodes 101, 103, and 104, respectively. A light-emitting element having region B, region 222G, and region 222R is formed on the substrate 200.

[0355] Step 6 The sixth step is to place a light-shielding layer 223, optical element 224B, and optical element 224 on the substrate 220. This is the process of forming G and the optical element 224R (see Figure 12(C)).

[0356] As the light-shielding layer 223, a resin film containing black pigment is formed in the desired area. After that, the base On the plate 220 and the light-shielding layer 223, optical element 224B, optical element 224G, and optical element 2 Forming 24R. As the optical element 224B, a resin film containing blue pigment is formed in the desired region. Formed. In addition, as the optical element 224G, a resin film containing green pigment is formed in a desired region. Furthermore, as the optical element 224R, a resin film containing red pigment is formed in the desired region. do.

[0357] ≪Step 7≫ The seventh step is to form a light-emitting element on substrate 200 and on substrate 220 The light-shielding layer 223, optical element 224B, optical element 224G, and optical element 224R are attached. This is the process of sealing the product using a sealing material (not shown in the diagram).

[0358] By following the above steps, the light-emitting element 262a shown in Figure 10(A) can be formed.

[0359] The configuration shown in this embodiment may be used in appropriate combination with the configurations shown in other embodiments. It is possible to be there.

[0360] (Embodiment 4) In this embodiment, a display device according to one aspect of the present invention will be described using Figures 13 to 23. I will reveal it.

[0361] <Example of display device configuration 1> Figure 13(A) is a top view showing the display device 600, and Figure 13(B) is the same as Figure 13(A) but with a dashed line. This is a cross-sectional view taken along lines AB and the dashed line CD. The display device 600 has a drive circuit section ( It has a signal line driving circuit section 601, a scan line driving circuit section 603, and a pixel section 602. Furthermore, the signal line drive circuit section 601, the scan line drive circuit section 603, and the pixel section 602 emit light. It has the function of controlling the light emission of the element.

[0362] Furthermore, the display device 600 includes an element substrate 610, a sealing substrate 604, and a sealing material 605. The area 607 surrounded by the sealing material 605, the routed wiring 608, and the FPC 609 are all included. do.

[0363] Furthermore, the routing wiring 608 is connected to the signal line drive circuit section 601 and the scan line drive circuit section 603. This is wiring for transmitting input signals, and it connects to the FPC609, which is an external input terminal, for video input. It receives signals such as the O signal, clock signal, start signal, and reset signal. Note that here it is FP Only C609 is shown in the diagram, but FPC609 is a printed circuit board (PWB: Pri A wired wiring board may be attached.

[0364] Furthermore, the signal line drive circuit section 601 consists of an N-channel type transistor 623 and a P-channel type A CMOS circuit is formed by combining it with transistor 624. The path section 601 or the scan line drive circuit section 603 includes various CMOS circuits, PMOS circuits, and An NMOS circuit can be used. In addition, in this embodiment, the drive circuit section is formed This shows a display device in which the driver and pixels are located on the same surface of the substrate, but this is not necessarily required. Alternatively, the drive circuit can be formed externally instead of on the circuit board.

[0365] Furthermore, the pixel section 602 includes a switching transistor 611 and a current control transistor. The lower part electrically connected to the drain of transistor 612 for current control and transistor 612 It has an electrode 613. A partition wall 614 is formed to cover the end of the lower electrode 613. A positive-type photosensitive acrylic resin film can be used as the partition wall 614.

[0366] Furthermore, in order to improve coverage, the upper or lower end of the partition wall 614 has a curved surface with curvature. To ensure that a structure is formed. For example, positive-type photosensitive acrylic is used as the material for the partition wall 614. If so, the upper end of the partition wall 614 will have a curve with a radius of curvature (0.2 μm or more and 3 μm or less). It is preferable to give it a surface. Also, as the partition wall 614, a negative type photosensitive resin or a poly Any type of photosensitive resin can be used.

[0367] Furthermore, the structure of the transistors (transistors 611, 612, 623, 624) is particularly... It is not limited. For example, a staggered transistor may be used. Also, the transistor There are no particular limitations regarding polarity, and it includes N-channel and P-channel transistors. A structure that includes either an N-channel transistor or a P-channel transistor. A structure consisting of only one of the two may also be used. Furthermore, the semiconductor film crystal used in transistors... There are no particular limitations regarding properties. For example, amorphous semiconductor films and crystalline semiconductor films can be used. Yes, it is possible. Also, as semiconductor materials, there are Group 14 (silicon, etc.) semiconductors and compound semiconductors (oxides). Semiconductors (including organic semiconductors), etc., can be used. Examples of transistors include: Energy gap of 2 eV or more, preferably 2.5 eV or more, more preferably 3 eV By using the above oxide semiconductors, the off-current of the transistor can be reduced. Preferably, the oxide semiconductor is In-Ga oxide, In-M-Zn oxide (M is Aluminum (Al), gallium (Ga), yttrium (Y), zirconium (Zr ), lanthanum (La), cerium (Ce), tin (Sn), hafnium (Hf), or ne Examples include odymium (Nd).

[0368] An EL layer 616 and an upper electrode 617 are formed on the lower electrode 613, respectively. The lower electrode 613 functions as the anode, and the upper electrode 617 functions as the cathode. ru.

[0369] Furthermore, the EL layer 616 is deposited using a deposition method (including vacuum deposition) with a deposition mask, and a droplet ejection method. Various coating methods such as (also called inkjet printing), spin coating, and gravure printing. It is formed by the method. In addition, the material constituting the EL layer 616 is a low molecular weight compound. Alternatively, it may be a polymer compound (including oligomers and dendrimers).

[0370] Furthermore, the lower electrode 613, the EL layer 616, and the upper electrode 617 contribute to the light-emitting element 618. The light-emitting element 618 is formed. The light-emitting element 618 has the configuration of Embodiments 1 to 3. It is preferable that this is the case. Note that if multiple light-emitting elements are formed in the pixel portion, then Embodiment 1 to This includes both the light-emitting element described in Embodiment 3 and light-emitting elements having other configurations. You can.

[0371] Furthermore, by bonding the sealing substrate 604 to the element substrate 610 with the sealing material 605, A light-emitting element is placed in the region 607 surrounded by the element substrate 610, the sealing substrate 604, and the sealing material 605. The structure is equipped with child 618. Furthermore, the area 607 is filled with filler material. In addition to cases where an inert gas (such as nitrogen or argon) is filled, it is also used in sealant 605. In some cases, it may be filled with UV-curing resin or thermosetting resin, for example, PVC ( Polyvinyl chloride resins, acrylic resins, polyimide resins, epoxy resins, Silicone resin, PVB (polyvinyl butyral) resin, or EVA (ethylene vinyl A resin (such as a luacetate) can be used. A recess is formed in the sealing substrate, and a desiccant is placed therein. Providing this feature can suppress deterioration due to moisture, making it a desirable configuration.

[0372] Furthermore, the optical element 621 is positioned below the sealing substrate 604 so as to overlap with the light-emitting element 618. It is provided therein. Furthermore, a light-shielding layer 622 is provided below the sealing substrate 604. Optical element 621 and the light-shielding layer 622 are the optical element and the light-shielding layer shown in Embodiment 3, respectively. A similar configuration would suffice.

[0373] Furthermore, it is preferable to use epoxy resin or glass frit for the sealant 605. Furthermore, it is desirable that these materials be as impermeable to moisture and oxygen as possible. In addition, as materials used for the sealing substrate 604, glass substrates and quartz substrates are also available, as well as FRP (Fiber Reinforced Plastic). Reinforced Plastics), PVF (Polyvinyl Fluoride), Poly A plastic substrate made of ester or acrylic can be used.

[0374] Here, we will explain the method for forming the EL layer 616 using the droplet ejection method, with reference to Figure 22. To clarify, Figures 22(A) to 22(D) are cross-sectional views illustrating the method for fabricating the EL layer 616. be.

[0375] First, in Figure 22(A), the lower electrode 613 and partition wall 614 are formed on the element substrate. Figure 610 is shown, but as in Figure 13, the lower electrode 613 and partition wall 614 are formed on the insulating film. A pre-assembled substrate may be used.

[0376] Next, the droplets from the droplet dispensing device 683 are dispensed onto the exposed portion of the lower electrode 613, which is the opening in the partition wall 614. A droplet 684 is dispensed to form a layer 685 containing the composition. The droplet 684 contains the solvent and composition. It is a substance that adheres to the lower electrode 613 (see Figure 22(B)).

[0377] The process of dispensing the droplet 684 may also be carried out under reduced pressure.

[0378] Next, the solvent is removed from the layer 685 containing the composition and solidified to form the EL layer 616. Form (see Figure 22(C)).

[0379] The solvent can be removed by either a drying or heating process.

[0380] Next, an upper electrode 617 is formed on the EL layer 616 to form a light-emitting element 618 (Figure 22). (See (D)).

[0381] When the EL layer 616 is formed by the droplet ejection method in this way, the composition can be selectively ejected. This allows for a reduction in material waste. Furthermore, lithography is used for shaping. Since processes such as injection molding are not required, the process can be simplified, resulting in lower costs.

[0382] The droplet dispensing method described above refers to a nozzle having an outlet for dispensing the composition, or a single nozzle. "Ku" refers to a general term for devices that have means for discharging droplets, such as heads with multiple nozzles.

[0383] Next, the droplet dispensing device used in the droplet dispensing method will be explained using Figure 23. This is a conceptual diagram illustrating the droplet dispensing device 1400.

[0384] The droplet dispensing device 1400 has a droplet dispensing means 1403. Also, the droplet dispensing means 140 Unit 3 has head 1405 and head 1412.

[0385] Heads 1405 and 1412 are connected to control means 1407, which is a computer By controlling it with the -1410, it is possible to draw on a pre-programmed pattern. can.

[0386] Furthermore, as for the timing of drawing, for example, the marker 1 formed on the substrate 1402 You can use 411 as the reference point. Alternatively, you can determine the reference point by using the outer edge of substrate 1402 as the reference point. It is also acceptable to do so. Here, marker 1411 is detected by imaging means 1404, and image processing means 1 The signal converted to digital in 409 is recognized by computer 1410 and a control signal is issued. It is then sent to the control unit 1407.

[0387] The imaging means 1404 may include a charge-coupled device (CCD) or a complementary metal oxide semiconductor (CM). Image sensors using an OS can be used. The information of the pattern to be performed is stored in the storage medium 1408, and based on this information A control signal is sent to the control means 1407, and the individual heads 1405 of the droplet dispensing means 1403, The head 1412 can be controlled individually. The material to be dispensed is supplied by the material supply source 1413. The supply source 1414 is supplied to heads 1405 and 1412 respectively through piping. ru.

[0388] The inside of head 1405 is a space 1406 for filling with liquid material, as indicated by the dotted line, and discharge It has a structure that includes a nozzle, which is the outlet. Although not shown in the diagram, head 1412 is also head 1 It has a similar internal structure to the 405. The nozzles of head 1405 and head 1412 are different. By using the 'Iz' setting, it becomes possible to simultaneously draw different materials in patterns of different widths. With a single head, it is possible to extrude multiple types of luminescent materials and draw patterns. Yes, it is possible. Also, when drawing patterns over a wide area, multiple methods can be used to improve throughput. The same material can be simultaneously dispensed from the nozzle and used for drawing. When using a large substrate, Head 1405 and head 1412 move on the circuit board in the directions of the X, Y, and Z arrows shown in Figure 23. The area to be scanned and drawn can be freely set, and the same pattern can be repeated on a single substrate. Numbers can be drawn.

[0389] Furthermore, the process of dispensing the composition may be carried out under reduced pressure. The substrate is heated during dispensing. This may also be done. After the composition is extruded, one or both of the following steps are performed: drying and / or calcination. Drying and calcination steps Both processes involve heat treatment, but their purpose, temperature, and time differ. The drying process, The firing process is carried out under normal or reduced pressure using laser irradiation, instantaneous heat annealing, heating furnaces, etc. The process is carried out as follows. The timing and number of times this heat treatment is performed are not particularly limited. To ensure successful drying and firing processes, the temperature at which these processes are performed depends on the properties of the substrate material and composition. It depends on.

[0390] As described above, the EL layer 616 can be fabricated using a droplet dispensing device.

[0391] As described above, the light-emitting element and optical element described in Embodiments 1 to 3 are A display device can be obtained.

[0392] <Example of display device configuration 2> Next, another example of a display device will be explained using Figures 14(A)(B) and 15. Figures 14(A)(B) and 15 are cross-sectional views of a display device according to one embodiment of the present invention. .

[0393] Figure 14(A) shows the substrate 1001, the underlayer insulating film 1002, the gate insulating film 1003, and the gate Electrodes 1006, 1007, 1008, first interlayer insulating film 1020, second interlayer insulating film 10 21, peripheral portion 1042, pixel portion 1040, drive circuit portion 1041, lower electrode 10 of light-emitting element 24R, 1024G, 1024B, partition wall 1025, EL layer 1028, upper electrode of light-emitting element 1026, the sealing layer 1029, the sealing substrate 1031, the sealing material 1032, etc. are shown in the diagram. .

[0394] Furthermore, in Figure 14(A), as an example of an optical element, a colored layer (red colored layer 1034R, A green colored layer 1034G and a blue colored layer 1034B are provided on a transparent substrate 1033. A light-shielding layer 1035 may also be provided. A transparent material having a colored layer and a light-shielding layer. The substrate 1033 is aligned and fixed to the substrate 1001. Note that the colored layer and the light-shielding layer are also included. It is covered with an overcoat layer 1036. Also, in Figure 14(A), the colored layer Since light passing through it is red, green, and blue, an image can be represented using pixels of these three colors.

[0395] Figure 14(B) shows an example of an optical element, with a colored layer (red colored layer 1034R, green colored layer The colored layer 1034G and the blue colored layer 1034B are connected to the gate insulating film 1003 and the first interlayer insulating film. An example of formation between film 1020 and the substrate 1001 is shown. In this way, the colored layer is sealed with the substrate 1001. It may also be provided between the substrates 1031.

[0396] Figure 15 shows an example of an optical element, with a colored layer (red colored layer 1034R, green colored layer) 1034G, the blue colored layer 1034B) is connected to the first interlayer insulating film 1020 and the second interlayer insulating film This shows an example of formation between 1021 and substrate 1001. Thus, the colored layer is formed between substrate 1001 and the sealing group It may also be provided between the plates 1031.

[0397] Furthermore, in the display device described above, the side of the substrate 1001 on which the transistor is formed Although a display device with a light extraction structure (bottom emission type) was used, on the encapsulating substrate 1031 side It can also be used as a display device with a structure that extracts light (top emission type).

[0398] <Example of display device configuration 3> An example of a cross-sectional view of a top-emission type display device is shown in Figure 16(A)(B). Figure 16 (A)(B) are cross-sectional views illustrating a display device according to one embodiment of the present invention, and Figure 14(A)(B ) and the drive circuit section 1041, peripheral section 1042, etc. shown in Figure 15 are omitted for illustrative purposes.

[0399] In this case, the substrate 1001 can be a substrate that does not transmit light. Until the connecting electrode that connects to the anode of the optical element is fabricated, it will be a bottom-emission type display device. It is formed in the same manner as above. Then, the third interlayer insulating film 1037 is formed so as to cover the electrode 1022. This insulating film may also play a planarization role. The third interlayer insulating film 1037 is In addition to materials similar to those used for the interlayer insulating film in step 2, it can be formed using a variety of other materials.

[0400] The lower electrodes 1024R, 1024G, and 1024B of the light-emitting element are referred to as anodes here, but the negative electrodes are not. It can also be a pole. Also, a top-emission type display like Figure 16(A)(B) is also acceptable. If it is a device, the lower electrodes 1024R, 1024G, and 1024B have the function of reflecting light. It is preferable to do so. Also, an upper electrode 1026 is provided on the EL layer 1028. Electrode 1026 has the function of reflecting light and the function of transmitting light, and lower electrode 1024R, 10 A microcavity structure is employed between 24G, 1024B and the upper electrode 1026. It is preferable to increase the light intensity at a specific wavelength.

[0401] In the top emission structure shown in Figure 16(A), the colored layer (red colored layer 1034) Encapsulation substrate 1031 provided with R, a green colored layer 1034G, and a blue colored layer 1034B) Sealing can be performed using this method. The sealing substrate 1031 is positioned between pixels. A light layer 1035 may be provided. Furthermore, if a light-transmitting substrate is used for the sealing substrate 1031, It is suitable.

[0402] Furthermore, in Figure 16(A), multiple light-emitting elements are shown, and each of these light-emitting elements is colored. While a configuration with layers has been given as an example, the system is not limited to this. For example, as shown in Figure 16(B) Without providing a green colored layer, a red colored layer 1034R and a blue colored layer 1034B are provided. Alternatively, a configuration that displays in full color using three colors—red, green, and blue—can be used. (See Figure 16(A)) As shown above, when a light-emitting element is provided and a colored layer is provided on each of the light-emitting elements, external light reflection This has the effect of suppressing it. On the other hand, as shown in Figure 16(B), the light-emitting element has a green If a configuration is used in which a red colored layer and a blue colored layer are provided without a colored layer, then green Because there is little energy loss from the light-emitting element, power consumption can be reduced. It produces the desired effect.

[0403] <Example of display device configuration 4> The display device described above has a configuration having three subpixels (red, green, and blue), A structure having subpixels of four colors (red, green, blue, yellow, or red, green, blue, white) It may be considered as a component. Figures 17 to 19 show the lower electrodes 1024R, 1024G, 1024B, And the configuration of a display device having 1024Y. Figures 17(A)(B) and 18 show the tra A structure (bottom emission type) that extracts light from the substrate 1001 where the inverter is formed. This is a display device, and Figure 19(A)(B) shows a structure that extracts light from the encapsulated substrate 1031 side. It is a top-emission type display device.

[0404] Figure 17(A) shows the optical elements (colored layer 1034R, colored layer 1034G, colored layer 1034B This is an example of a display device in which a colored layer (1034Y) is provided on a transparent substrate (1033). Also, see Figure 17. (B) is an optical element (colored layer 1034R, colored layer 1034G, colored layer 1034B) This is an example of a display device formed between the insulating film 1003 and the first interlayer insulating film 1020. Figure 18 shows the optical element (colored layer 1034R, colored layer 1034G, colored layer 1034B, A color layer (1034Y) is formed between the first interlayer insulating film 1020 and the second interlayer insulating film 1021. This is an example of a display device.

[0405] Colored layer 1034R transmits red light, colored layer 1034G transmits green light, colored layer 1034B has the function of transmitting blue light. In addition, the colored layer 1034Y transmits yellow light. A function that allows light to pass through, or a function that transmits multiple colors selected from blue, green, yellow, and red. The colored layer 1034Y transmits multiple lights selected from blue, green, yellow, and red. When it has the function of being yellow, the light transmitted through the colored layer 1034Y may be white. Because light-emitting elements that emit white light have high luminous efficiency, a display having a colored layer 1034Y The device can reduce power consumption.

[0406] Furthermore, in the top-emission type display device shown in Figure 19, the lower electrode 1024Y In the light-emitting element having the same upper electrode 1026 as in the display device in Figure 16(A), A configuration having a microcavity structure in between is preferred. Also, the display device in Figure 19(A) So, the colored layers (red colored layer 1034R, green colored layer 1034G, blue colored layer 103 The sealing can be performed with a sealing substrate 1031 having 4B and a yellow colored layer 1034Y). ru.

[0407] The emission exhibited through the microcavity and the yellow colored layer 1034Y is in the yellow region. The emission will have an emission spectrum in the region. Since yellow is a color with high visual sensitivity, yellow emission will occur. A light-emitting element exhibiting this characteristic has high luminous efficiency. That is, a display device having the configuration shown in Figure 19(A) is This can reduce power consumption.

[0408] Furthermore, in Figure 19(A), multiple light-emitting elements are shown, and each of these light-emitting elements is colored. While a configuration with layers has been given as an example, the system is not limited to this. For example, as shown in Figure 19(B) Without providing a yellow colored layer, a red colored layer 1034R, a green colored layer 1034G, and a blue colored layer are provided. A colored layer 1034B is provided, and four colors are used: red, green, blue, and yellow, or red, green, blue, and white. A configuration that enables full-color display may also be used. As shown in Figure 19(A), a light-emitting element and the When a colored layer is provided on each optical element, it has the effect of suppressing external light reflection. It performs. On the other hand, as shown in Figure 19(B), the light-emitting element is made without a yellow colored layer, and red If the configuration includes a colored layer, a green colored layer, and a blue colored layer, then yellow or white Because there is little energy loss from the light-emitting element, power consumption can be reduced. It produces the desired effect.

[0409] <Example of display device configuration 5> Next, another embodiment of the present invention is shown in Figure 20. Figure 20 is a representation of Figure 13(A This is a cross-sectional view taken along the dashed lines AB and CD of ). Note that in Figure 20... Therefore, parts having the same function as those shown in Figure 13(B) are denoted with the same reference numerals, and their details I will omit the detailed explanation.

[0410] The display device 600 shown in Figure 20 consists of an element substrate 610, a sealing substrate 604, and a sealing material 60 The region 607 enclosed by 5 has sealing layers 607a, 607b, and 607c. One or more of the sealing layers 607a, 607b, and 607c may include, for example, For example, PVC (polyvinyl chloride) resin, acrylic resin, polyimide resin, etc. Poxy resins, silicone resins, PVB (polyvinyl butyral) resins, or EVA Resins such as (ethylene vinyl acetate) resins can be used. Also, silica oxide Silicon oxide nitride, silicon nitride, silicon nitride, aluminum oxide, aluminum nitride Inorganic materials such as titanium may also be used. Sealing layer 607a, sealing layer 607b, sealing layer 607 By forming c, the degradation of the light-emitting element 618 due to impurities such as water can be suppressed. Preferred. When forming sealing layer 607a, sealing layer 607b, and sealing layer 607c, It is not necessary to provide the 605 material.

[0411] Furthermore, sealing layers 607a, 607b, and 607c may be one or two of each. It may be the case that four or more sealing layers are formed. By making the sealing layers multilayered, water These impurities can penetrate from outside the display device 600 to the light-emitting element 618 inside the display device. This is preferable because it can effectively prevent this. Furthermore, if the sealing layer is multilayered, the resin and inorganic material A preferred configuration involves layering the materials.

[0412] <Example of display device configuration 6> Furthermore, the display devices shown in Configuration Examples 1 to 4 of this embodiment have optical elements. Although the above configuration has been illustrated, in one aspect of the present invention, optical elements may not be provided.

[0413] The display device shown in Figures 21(A) and (B) has a structure that extracts light from the sealing substrate 1031 side ( This is a display device of the emitting type. Figure 21(A) shows the emitting layer 1028R and the emitting layer 1 This is an example of a display device having 028G and a light-emitting layer 1028B. Also, Figure 21(B) shows A table having a light layer 1028R, an emissive layer 1028G, an emissive layer 1028B, and an emissive layer 1028Y. This is an example of a display device.

[0414] The light-emitting layer 1028R emits red light, and the light-emitting layer 1028G emits green light. The light-emitting layer 1028B has the function of emitting blue light. The light-emitting layer 1028Y emits yellow light. A function that emits light, or a function that emits multiple lights selected from blue, green, and red. It has. The light emitted by the light-emitting layer 1028Y may be white. Yellow or white Because the light-emitting element has high luminous efficiency, a display device having the light-emitting layer 1028Y is It can reduce power consumption.

[0415] The display devices shown in Figures 21(A) and 21(B) include an EL layer that emits light of different colors. Since it is contained within the pixel, it is not necessary to provide a colored layer that acts as an optical element.

[0416] Furthermore, the sealing layer 1029 may be made of, for example, PVC (polyvinyl chloride) resin, acrylic Polyimide resins, epoxy resins, silicone resins, PVB (polyvinyl blue resin) Using resins such as ethylene vinyl acetate (EVA) resin or ethylene vinyl acetate resin. It is possible to do this. Also, silicon oxide, silicon oxide nitride, silicon oxide nitride, silicon nitride Inorganic materials such as aluminum oxide and aluminum nitride may also be used. The sealing layer 1029 Forming it this way is preferable because it can suppress the deterioration of the light-emitting element due to impurities such as water.

[0417] Furthermore, the sealing layer 1029 may consist of one or two of any four or more sealing layers. A layer may be formed. By making the sealing layer multilayered, impurities such as water can enter the outside of the display device. This is preferable because it can effectively prevent penetration into the interior of the display device. In the case of a multilayer structure, a preferred configuration is one in which resin and inorganic material are laminated together.

[0418] Furthermore, the encapsulating substrate 1031 only needs to have a function to protect the light-emitting element. Therefore, a flexible substrate or film can be used for the sealing substrate 1031.

[0419] Note that the configuration shown in this embodiment may be appropriately combined with other embodiments or other configurations within this embodiment. They can be combined.

[0420] (Embodiment 5) In this embodiment, a display device having an light-emitting element according to one aspect of the present invention is shown in Figures 24 to We will explain using Figure 26.

[0421] Figure 24(A) is a block diagram illustrating a display device according to one embodiment of the present invention, and Figure 2 4(B) is a circuit diagram illustrating a pixel circuit in a display device according to one aspect of the present invention.

[0422] <Explanation regarding display devices> The display device shown in Figure 24(A) has a region having pixels of the display element (hereinafter referred to as the pixel portion 802 and ( ) and a circuit section ( ) which is located outside the pixel section 802 and has a circuit for driving the pixels. Hereinafter referred to as the drive circuit section 804, and a circuit having a function to protect the element (hereinafter referred to as the protection circuit 804) It has a (6) and a terminal section 807. Note that the protection circuit 806 is not provided. That's fine.

[0423] Part or all of the drive circuit section 804 is formed on the same substrate as the pixel section 802. This is desirable. This allows for a reduction in the number of components and terminals. Drive circuit section 804 If part or all of it is not formed on the same substrate as the pixel section 802, the drive cycle Part or all of road section 804 is COG or TAB (Tape Automated B It can be implemented by (onding).

[0424] The pixel section 802 is arranged in X rows (where X is a natural number greater than or equal to 2) and Y columns (where Y is a natural number greater than or equal to 2). It has a circuit for driving multiple display elements (hereinafter referred to as the pixel circuit 801), and the drive cycle The path section 804 is a circuit that outputs a signal (scan signal) for selecting pixels (hereinafter referred to as the scan line drive circuit). 804a) is used to supply signals (data signals) for driving the pixel display elements. It has a drive circuit such as the signal line drive circuit 804b.

[0425] The scan line driving circuit 804a includes a shift register and the like. A signal to drive the shift register is input via terminal 807, and the signal is output. For example, the scan line drive circuit 804a receives a start pulse signal, a clock signal, etc. The scan line drive circuit 804a outputs a pulse signal. The scanning signal is supplied to the wiring (and It has the function of controlling the potential of the scan lines (referred to as GL_1 to GL_X). Multiple drive circuits 804a are provided, and the scan line GL_1 is driven by multiple scan line drive circuits 804a. The path to GL_X may be divided and controlled. Alternatively, the scan line drive circuit 804a may use an initialization signal. It has the function of supplying, however, the scan line drive circuit 80 4a can also supply another signal.

[0426] The signal line drive circuit 804b includes a shift register, etc. The signal line drive circuit 804b is Through terminal 807, in addition to signals for driving the shift register, the data signals are generated. A signal (image signal) is input. The signal line drive circuit 804b uses the image signal to drive the pixel circuit It has the function of generating data signals to be written to 801. In addition, the signal line drive circuit 804b The data signal is transmitted according to the pulse signal obtained by inputting the start pulse, clock signal, etc. It has the function of controlling the output of the signal. In addition, the signal line drive circuit 804b is provided with a data signal. It has the function of controlling the potential of the wiring (hereinafter referred to as data lines DL_1 to DL_Y). Alternatively, the signal line drive circuit 804b has the function of supplying an initialization signal. However, it is not limited to this, and the signal line drive circuit 804b may also supply other signals. It is possible.

[0427] The signal line drive circuit 804b is configured using, for example, multiple analog switches. The signal line drive circuit 804b sequentially turns on multiple analog switches, The image signal can be time-divided and output as a data signal. It can also use shift registers, etc. The signal line drive circuit 804b may be constructed using this.

[0428] Each of the multiple pixel circuits 801 receives a scan signal from one of the multiple scan lines GL. A pulse signal is input via one of several data lines DL to which a data signal is supplied. A data signal is input. In addition, each of the multiple pixel circuits 801 is a scan line drive circuit 804a controls the writing and retention of data in the data signal. For example, m rows and n columns. The pixel circuit 801 of the eye is connected to the scan line drive circuit via the scan line GL_m (where m is a natural number less than or equal to X). A pulse signal is input from 804a, and the data line DL_n( A data signal is input from the signal line drive circuit 804b via n (where n is a natural number less than or equal to Y).

[0429] The protection circuit 806 shown in Figure 24(A) is, for example, a scan line drive circuit 804a and a pixel circuit 8 It is connected to the scan line GL, which is the wiring between 01. Alternatively, the protection circuit 806 drives the signal line. It is connected to the data line DL, which is the wiring between circuit 804b and pixel circuit 801. Alternatively, The protection circuit 806 is connected to the wiring between the scan line drive circuit 804a and the terminal section 807. Yes, it is possible. Alternatively, the protection circuit 806 provides a connection between the signal line drive circuit 804b and the terminal section 807. It can be connected to a wire. The terminal 807 is used to supply power and to the display device from an external circuit. This refers to the part equipped with terminals for inputting control signals and image signals.

[0430] The protection circuit 806, when a potential outside a certain range is applied to the wiring to which it is connected, This is a circuit that creates a conductive state between two wires.

[0431] As shown in Figure 24(A), the pixel unit 802 and the drive circuit unit 804 each have a protection circuit 80 By connecting 6, ESD (Electrostatic Discharge) This can improve the resistance of the display device to overcurrents generated by electrostatic discharge, etc. However, the configuration of the protection circuit 806 is not limited to this; for example, the scan line drive circuit 804a A configuration in which the protection circuit 806 is connected to the signal line drive circuit 804b, or a configuration in which the protection circuit 806 is connected to the signal line drive circuit 804b. A continuous configuration is also possible. Alternatively, a configuration in which the protection circuit 806 is connected to the terminal 807 is also possible. It can also be written as "completion".

[0432] Furthermore, in Figure 24(A), the scan line drive circuit 804a and the signal line drive circuit 804b are Therefore, although an example is shown in which the drive circuit section 804 is formed, the configuration is not limited to this. For example, only the scan line drive circuit 804a is formed, and a separately prepared signal line drive circuit is formed. A substrate (for example, a drive circuit substrate formed from a single-crystal semiconductor film or a polycrystalline semiconductor film) is mounted. This configuration is also good.

[0433] <Example of pixel circuit configuration> The multiple pixel circuits 801 shown in Figure 24(A) may be configured as shown in Figure 24(B), for example. It is possible.

[0434] The pixel circuit 801 shown in Figure 24(B) consists of transistors 852 and 854 and a capacitive element 86 It has 2 and a light-emitting element 872.

[0435] One of the source and drain electrodes of transistor 852 is supplied with a data signal. It is electrically connected to the wiring (data line DL_n). Furthermore, the gate of transistor 852 The electrodes are electrically connected to the wiring (scan line GL_m) to which the gate signal is applied.

[0436] Transistor 852 has the function of controlling the writing of data to the data signal.

[0437] One of the pair of electrodes of the capacitive element 862 is connected to a wiring to which a potential is supplied (hereinafter referred to as the potential supply line VL). It is electrically connected to (a), and the other is the source electrode and drain of transistor 852. It is electrically connected to the other electrode.

[0438] The capacitive element 862 functions as a holding capacitor to retain the written data.

[0439] One of the source and drain electrodes of transistor 854 is connected to the potential supply line VL_a. They are electrically connected. Furthermore, the gate electrode of transistor 854 is connected to the gate electrode of transistor 852. It is electrically connected to the other of the source electrode and drain electrode.

[0440] One of the anodes and cathodes of the light-emitting element 872 is electrically connected to the potential supply line VL_b. The other end is electrically connected to the source and drain electrodes of transistor 854. It will be done.

[0441] As the light-emitting element 872, the light-emitting elements shown in Embodiments 1 to 3 are used. It is possible.

[0442] Furthermore, a high power supply potential VDD is supplied to one of the potential supply lines VL_a and VL_b. On the other hand, a low power supply potential VSS is applied.

[0443] In a display device having the pixel circuit 801 shown in Figure 24(B), for example, the running shown in Figure 24(A) The line drive circuit 804a sequentially selects the pixel circuit 801 for each row, and the transistor 852 Turn it on and write the data signal.

[0444] When data is written to the pixel circuit 801, the transistor 852 turns off. It enters a holding state. Furthermore, in accordance with the potential of the written data signal, transistor 854 The amount of current flowing between the source electrode and the drain electrode is controlled, and the light-emitting element 872 controls the amount of current flowing through it. It emits light with brightness corresponding to the flow rate. By performing this sequentially for each row, an image can be displayed.

[0445] Furthermore, the pixel circuit has a function to compensate for the effects of fluctuations in the transistor threshold voltage, etc. This may be done. Figures 25(A)(B) and 26(A)(B) show examples of pixel circuits.

[0446] The pixel circuit shown in Figure 25(A) consists of six transistors (transistors 303_1 to 303_3). It has 03_6), a capacitive element 304, and a light-emitting element 305. Also, Figure 25(A) The pixel circuit shown includes wiring 301_1 to 301_5, as well as wiring 302_1 and wiring 30 2_2 is electrically connected. Regarding transistors 303_1 to 303_6... For example, a P-channel transistor can be used.

[0447] The pixel circuit shown in Figure 25(B) is the same as the pixel circuit shown in Figure 25(A), but with transistor 303 This configuration includes the addition of _7. Also, the pixel circuit shown in Figure 25(B) has wiring 301_6 and Wiring 301_7 is electrically connected. Here, wiring 301_5 and wiring 301_6 These may be electrically connected to each other. Regarding transistor 303_7... For example, a P-channel transistor can be used.

[0448] The pixel circuit shown in Figure 26(A) consists of six transistors (transistors 308_1 to 308_3). It has 08_6), a capacitive element 304, and a light-emitting element 305. Also, Figure 26(A) The pixel circuit shown includes wiring 306_1 to 306_3, and wiring 307_1 to 307_ 3 is electrically connected. Here, wiring 306_1 and wiring 306_3 are electrically connected. They may be electrically connected. Regarding transistors 308_1 to 308_6: For example, a P-channel transistor can be used.

[0449] The pixel circuit shown in Figure 26(B) consists of two transistors (transistor 309_1 and Rangitator 309_2) and two capacitive elements (capacitive element 304_1 and capacitive element 304_ 2) and a light-emitting element 305 are included. Also, the pixel circuit shown in Figure 26(B) has wiring 3 Wirings 11_1 to 311_3, 312_1, and 312_2 are electrically connected. Furthermore, by using the pixel circuit configuration shown in Figure 26(B), for example, voltage input - power A flow-driven system (also called a CVCC system) can be used. Note that transistor 309_ For 1 and 309_2, for example, a P-channel transistor can be used. .

[0450] Furthermore, a light-emitting element according to one aspect of the present invention is an active element having an active element in the pixels of a display device. Trix system, or passive matrix system in which the pixels of the display device do not have active elements. It can be applied to each method.

[0451] In the active matrix system, the active elements (active elements, nonlinear elements) are, In addition to transistors, various active elements (active elements, nonlinear elements) can be used. This can be done. For example, MIM (Metal Insulator Metal), or T It is also possible to use elements such as FD (Thin Film Diode). Because it involves fewer manufacturing steps, it is possible to reduce manufacturing costs or improve yield. Alternatively, these elements can improve the aperture ratio due to their small size. This allows for lower power consumption and higher brightness.

[0452] Other than the active matrix method, there are active elements (active elements, nonlinear elements) It is also possible to use a passive matrix type that does not use active elements. Because it does not use sub-elements or nonlinear elements, the manufacturing process is simpler, resulting in reduced manufacturing costs or higher yield. This can improve the performance. Alternatively, active elements (active elements, nonlinear elements) can be used. Because it does not exist, the aperture ratio can be improved, leading to lower power consumption or higher brightness. It is possible.

[0453] The configuration shown in this embodiment may be used in appropriate combination with the configurations shown in other embodiments. It is possible.

[0454] (Embodiment 6) In this embodiment, a display device having a light-emitting element according to one aspect of the present invention, and the display device An electronic device with an input device attached will be explained using Figures 27 to 31.

[0455] <Explanation regarding the touch panel 1> In this embodiment, as an example of electronic equipment, a display device and an input device are combined. This document describes the Touch Panel 2000. It also explains the Touch Sensor as an example of an input device. This section explains the case where the character "Sa" is present.

[0456] Figures 27(A) and 27(B) are perspective views of the touch panel 2000. In section B), for clarity, typical components of the touch panel 2000 are shown.

[0457] The touch panel 2000 has a display device 2501 and a touch sensor 2595 (Figure 2). See 7(B). Also, the touch panel 2000 is made up of substrate 2510, substrate 2570, and substrate It has a plate 2590. Note that substrates 2510, 2570, and 2590 are all It is flexible. However, any one of substrates 2510, 2570, and 2590 The configuration may be one or all of which lack flexibility.

[0458] The display device 2501 has multiple pixels on the substrate 2510 and supplies signals to these pixels. It has multiple wirings 2511. The multiple wirings 2511 are located on the outer periphery of the substrate 2510. It is routed through, and a portion of it forms terminal 2519. Terminal 2519 is FPC2509 (1) is electrically connected to the signal line drive circuit 2503s. The signal from (1) can be supplied to multiple pixels.

[0459] The circuit board 2590 has a touch sensor 2595 and is electrically connected to the touch sensor 2595. It has multiple wires 2598. The multiple wires 2598 are routed around the outer periphery of the substrate 2590. A portion of it forms a terminal. This terminal is electrically connected to FPC2509(2). The process continues. Note that in Figure 27(B), for clarity, the back side of substrate 2590 (substrate 2510) is shown. The electrodes and wiring of the touch sensor 2595, which is located on the opposite side, are shown with solid lines. .

[0460] For example, a capacitive touch sensor can be used as the touch sensor 2595. Capacitive capacitance methods include surface capacitance and projected capacitance.

[0461] Projected capacitance systems are classified into self-capacitance and mutual-capacitance types, mainly based on differences in their driving methods. There are several advantages. Using a mutual capacitance method is preferable because it enables simultaneous multi-point detection.

[0462] Note that the touch sensor 2595 shown in Figure 27(B) is a projected capacitive touch sensor. This configuration applies the "S" principle.

[0463] Furthermore, the touch sensor 2595 can detect the proximity or contact of an object to be detected, such as a finger. Yes, various sensors can be applied.

[0464] The projected capacitive touch sensor 2595 has electrodes 2591 and 2592. Electrode 2591 is electrically connected to one of the multiple wires 2598, and electrode 2592 is Connect electrically to any of the other wires 2598.

[0465] As shown in Figures 27(A) and 27(B), the electrode 2592 is arranged in multiple repeating directions. It has a shape in which the quadrilaterals are connected at their corners.

[0466] Electrode 2591 is quadrilateral and repeats in a direction intersecting the direction in which electrode 2592 extends. It is positioned.

[0467] Wiring 2594 is electrically connected to the two electrodes 2591 that sandwich electrode 2592. A shape that minimizes the area of ​​the intersection between electrode 2592 and wiring 2594 is preferable. This reduces the area where electrodes are not provided, thereby reducing variations in transmittance. Yes, it is possible. As a result, it reduces the variation in brightness of the light transmitted through the touch sensor 2595. It is possible.

[0468] Note that the shapes of electrodes 2591 and 2592 are not limited to these and can take on various shapes. For example, multiple electrodes 2591 are arranged so that there are as few gaps as possible, and an insulating layer is used. Multiple electrodes 2592 are provided spaced apart so that there is a region that does not overlap with electrode 2591. This configuration may also be used. In this case, between the two adjacent electrodes 2592, there is an electrical connection between them. Providing an insulated dummy electrode is preferable because it reduces the area of ​​regions with different transmittances. .

[0469] <Explanation regarding display devices> Next, we will explain the details of the display device 2501 using Figure 28(A). This corresponds to the cross-sectional view between the dashed line X1 and X2 shown in Figure 27(B).

[0470] The display device 2501 has a plurality of pixels arranged in a matrix. These pixels are display elements. It has a child and a pixel circuit that drives the display element.

[0471] The following explanation applies to the case where a light-emitting element that emits white light is applied to the display element. As explained above, the display elements are not limited to these. For example, the light emitted from each adjacent pixel You may use light-emitting elements with different emission colors to achieve a different color.

[0472] For example, substrates 2510 and 2570 have a water vapor transmission rate of 1 × 10⁻⁶ -5 g. m -2 ·day -1 The following is preferably 1 × 10 -6 g·m -2 ·day -1 The following is possible Flexible materials can be suitably used. Alternatively, the thermal expansion coefficient of the substrate 2510 and the base It is preferable to use a material whose thermal expansion coefficient is approximately equal to that of plate 2570. For example, linear expansion coefficient is 1 x 10 -3 / K or less, preferably 5 × 10 -5 / K or less, more comfortable 1×10 - 5 Materials with a temperature of / K or lower can be suitably used.

[0473] The substrate 2510 includes an insulating layer 2510a that prevents the diffusion of impurities to the light-emitting element, and a flexible Adhesive layer 2 for bonding substrate 2510b, insulating layer 2510a, and flexible substrate 2510b It is a laminate having 510c. Furthermore, the substrate 2570 is a laminate that allows impurities to diffuse into the light-emitting element. An insulating layer 2570a to prevent leakage, a flexible substrate 2570b, and the insulating layer 2570a and the flexible substrate The laminate has an adhesive layer 2570c that bonds 2570b together.

[0474] Examples of adhesive layers 2510c and 2570c include polyester, polyolefin, etc. Polyamide (nylon, aramid, etc.), polyimide, polycarbonate, or acrylic Polyurethane, epoxy resin, or silicone can be used. Any material containing a resin with siloxane bonds can be used.

[0475] Furthermore, a sealing layer 2560 is provided between substrate 2510 and substrate 2570. (Sealing layer 2560) It is preferable that it has a refractive index greater than that of air. Also, as shown in Figure 28(A), sealing If light is to be extracted to the layer 2560 side, the sealing layer 2560 can also serve as an optical bonding layer. Cut.

[0476] Furthermore, a sealing material may be formed on the outer periphery of the sealing layer 2560. As a result, the region surrounded by substrate 2510, substrate 2570, sealing layer 2560, and sealing material The configuration can include a light-emitting element 2550R. The sealing layer 2560 is as follows: An inert gas (such as nitrogen or argon) may be used to fill the container. Furthermore, a desiccant may be placed inside the inert gas. A structure that adsorbs moisture, etc., may be provided. Alternatively, a resin such as acrylic or epoxy may be used. It may also be filled with oil. Furthermore, as the sealing material mentioned above, for example, epoxy resin or It is preferable to use glass frit. Also, the material used for the sealant should be free of moisture and acid. It is preferable to use a material that does not allow light to pass through.

[0477] Furthermore, the display device 2501 has pixels 2502R. Also, pixels 2502R are light-emitting pixels. It has a joule of 2580R.

[0478] Pixel 2502R is connected to the light-emitting element 2550R and supplies power to the light-emitting element 2550R. It has a transistor 2502t that can do this. Note that transistor 2502t is a pixel It functions as part of the circuit. Also, the light-emitting module 2580R and the light-emitting element 2550R, It has a colored layer 2567R.

[0479] The light-emitting element 2550R has a lower electrode, an upper electrode, and an EL layer between the lower electrode and the upper electrode. It has the following characteristics. As the light-emitting element 2550R, for example, the light-emitting elements shown in Embodiments 1 to 3 Optical elements can be applied.

[0480] Furthermore, a microcavity structure is employed between the lower electrode and the upper electrode, allowing for specific wavelengths. The light intensity may be increased.

[0481] Furthermore, if the sealing layer 2560 is provided on the side from which light is extracted, the sealing layer 2560 is It is in contact with the optical element 2550R and the colored layer 2567R.

[0482] The colored layer 2567R is located in a position that overlaps with the light-emitting element 2550R. A portion of the light emitted by 2550R passes through the colored layer 2567R, and is emitted in the direction of the arrow shown in the figure. It is emitted to the outside of the 2580R optical module.

[0483] Furthermore, the display device 2501 is provided with a light-shielding layer 2567BM in the direction from which light is emitted. The light-shielding layer 2567BM is provided so as to surround the colored layer 2567R.

[0484] The colored layer 2567R only needs to have the function of transmitting light in a specific wavelength band. For example, a color filter that transmits light in the red wavelength range, and a color filter that transmits light in the green wavelength range. Color filters, color filters that transmit light in the blue wavelength range, color filters that transmit light in the yellow wavelength range Transparent color filters can be used. Each color filter is made from various materials. Using printing methods, inkjet methods, and etching methods using photolithography technology, It can be formed in any way.

[0485] Furthermore, the display device 2501 is provided with an insulating layer 2521. The insulating layer 2521 is made of transistors. It covers the ZISTA 2502t. The insulating layer 2521 flattens the irregularities caused by the pixel circuit. It has the function to do so. In addition, the insulating layer 2521 is given the function to suppress the diffusion of impurities. This may be done. This will prevent a decrease in the reliability of transistors such as the 2502t due to the diffusion of impurities. It can be suppressed.

[0486] Furthermore, the light-emitting element 2550R is formed above the insulating layer 2521. The lower electrode of the 550R is provided with a partition wall 2528 that overlaps the end of the lower electrode. Furthermore, a spacer that controls the distance between substrate 2510 and substrate 2570 is placed on the partition wall 2528. It may be formed.

[0487] The scan line driving circuit 2503g(1) consists of a transistor 2503t and a capacitive element 2503c It has the following characteristics. Furthermore, the drive circuit can be formed on the same substrate using the same process as the pixel circuit. ru.

[0488] Furthermore, wiring 2511 that can supply signals is provided on the circuit board 2510. Furthermore, terminal 2519 is provided on wiring 2511. Also, terminal 2519 has FP C2509(1) is electrically connected. Also, FPC2509(1) receives the video signal. It has the function of supplying clock signals, start signals, reset signals, etc. Note: FPC2 A printed circuit board (PWB) may be attached to 509(1).

[0489] Furthermore, transistors of various structures can be applied to the display device 2501. (Figure) In 28(A), an example is given of the case where a bottom-gate type transistor is applied. However, it is not limited to this, and for example, as shown in Figure 28(B), a top-gate type transient The system may also be configured to apply to the display device 2501.

[0490] Furthermore, regarding the polarity of transistors 2502t and 2503t, there are no particular limitations. There is no fixed definition, and the structure has N-channel and P-channel transistors, N-channel type A structure consisting of either a transistor or a P-channel transistor is used. It may be there. Also, the semiconductor film crystal used in transistors 2502t and 2503t There are no particular limitations regarding properties. For example, amorphous semiconductor films and crystalline semiconductor films can be used. Yes, it is possible. Also, as a semiconductor material, Group 14 semiconductors (for example, semiconductors containing silicon) are used. Compound semiconductors (including oxide semiconductors), organic semiconductors, etc. can be used. Either or both of transistors 2502t and 2503t have energy gear Oxides with a cap of 2 eV or more, preferably 2.5 eV or more, and more preferably 3 eV or more. Using semiconductors is preferable because it reduces the transistor's off-current. Examples of such oxide semiconductors include In-Ga oxide and In-M-Zn oxide (where M is Al, G). Examples include (representing a, Y, Zr, La, Ce, Sn, Hf, or Nd).

[0491] <Explanation regarding touch sensors> Next, we will explain the details of the touch sensor 2595 using Figure 28(C). Figure 28 (C) corresponds to the cross-sectional view between the dashed line X3 and X4 shown in Figure 27(B).

[0492] The touch sensor 2595 has electrodes 2591 and electrodes arranged in a staggered pattern on the substrate 2590. 2592, an insulating layer 2593 covering electrodes 2591 and 2592, and adjacent electrodes 25 It has wiring 2594 that electrically connects 91.

[0493] Electrodes 2591 and 2592 are formed using a light-transmitting conductive material. Conductive materials having this property include indium oxide, indium tin oxide, and indium zinc oxide. Conductive oxides such as zinc oxide, zinc oxide, and zinc oxide with added gallium can be used. Furthermore, a film containing graphene can also be used. A film containing graphene is, for example, a film-like film. A film containing graphene oxide formed on the surface can be reduced to form a new film. Methods such as applying heat can be cited.

[0494] For example, a light-transmitting conductive material is deposited on a substrate 2590 by sputtering. Afterward, unwanted parts are removed using various pattern formation techniques such as photolithography. Electrodes 2591 and 2592 can be formed.

[0495] Furthermore, the materials used for the insulating layer 2593 include, for example, acrylic resin, epoxy resin, etc. In addition to resins containing siloxane bonds such as silicones, silicon oxide and nitridation are also included. Inorganic insulating materials such as silicon and aluminum oxide can also be used.

[0496] Furthermore, an opening reaching the electrode 2591 is provided in the insulating layer 2593, and the wiring 2594 is adjacent to it. It is electrically connected to electrode 2591. The light-transmitting conductive material increases the aperture ratio of the touch panel. Because it can be done this way, it can be suitably used in wiring 2594. Also, electrode 2591 Furthermore, materials with higher conductivity than electrode 2592 are preferable for wiring 2594 because they can reduce electrical resistance. It can be used appropriately.

[0497] The electrode 2592 extends in one direction, and multiple electrodes 2592 are arranged in a stripe pattern. Furthermore, the wiring 2594 is provided intersecting with the electrode 2592.

[0498] A pair of electrodes 2591 are provided flanking one electrode 2592. Also, the wiring 2594 is A pair of electrodes 2591 are electrically connected.

[0499] Note that the multiple electrodes 2591 are not necessarily arranged in a direction perpendicular to that of a single electrode 2592. It is not necessary to do so; they may be arranged to form an angle greater than 0 degrees but less than 90 degrees.

[0500] Furthermore, wiring 2598 is electrically connected to electrode 2591 or electrode 2592. A portion of the wiring 2598 functions as a terminal. Wiring 2598 can be, for example, made of aluminum. Nium, gold, platinum, silver, nickel, titanium, tungsten, chromium, molybdenum, iron, corn Using metallic materials such as balsamic, copper, or palladium, or alloy materials containing such metallic materials. It is possible.

[0501] Furthermore, an insulating layer is provided to cover the insulating layer 2593 and the wiring 2594, and the touch sensor 2595 It may be protected.

[0502] Furthermore, the connecting layer 2599 electrically connects the wiring 2598 and the FPC2509(2). .

[0503] The connecting layer 2599 is an anisotropic conductive film (ACF: Anisotropic C (conductive film) or anisotropic conductive paste (ACP: Anisotropic) You can use tools such as IC Conductive Paste.

[0504] <Explanation regarding the touch panel 2> Next, we will explain the details of the touch panel 2000 using Figure 29(A). Figure 29 (A) corresponds to the cross-sectional view between the dashed line X5 and X6 shown in Figure 27(A).

[0505] The touch panel 2000 shown in Figure 29(A) is the same as the display device 250 described in Figure 28(A). This configuration consists of 1 and the touch sensor 2595 described in Figure 28(C) bonded together.

[0506] Furthermore, the touch panel 2000 shown in Figure 29(A) is shown in Figures 28(A) and 28(C). In addition to the configuration described, it also includes an adhesive layer 2597 and an anti-reflective layer 2567p.

[0507] The adhesive layer 2597 is provided in contact with the wiring 2594. The substrate 2590 is attached to the substrate 2570 so that the sensor 2595 overlaps the display device 2501. They are joined together. Furthermore, it is preferable that the adhesive layer 2597 has light-transmitting properties. Also, adhesive layer 2 For 597, a thermosetting resin or an ultraviolet curing resin can be used. For example, Using acrylic resin, urethane resin, epoxy resin, or siloxane resin It is possible.

[0508] The anti-reflective layer 2567p is provided in a position that overlaps with the pixel. For example, a circular polarizer can be used.

[0509] Next, for a touch panel with a configuration different from that shown in Figure 29(A), see Figure 29(B). I will use it to explain.

[0510] Figure 29(B) is a cross-sectional view of the touch panel 2001. The touch panel shown in Figure 29(B) Nell 2001 is a touch panel 2000 and a display device 2501 as shown in Figure 29(A). The position of the touch sensor 2595 is different. Here, we will explain the different configurations in detail. Where applicable, refer to the description of Touch Panel 2000 for details on how to use the provided configuration.

[0511] The colored layer 2567R is located in a position that overlaps with the light-emitting element 2550R. Also, in Figure 29(B) The light-emitting element 2550R shown emits light on the side where the transistor 2502t is located. As a result, some of the light emitted by the light-emitting element 2550R passes through the colored layer 2567R, The light is emitted to the outside of the light-emitting module 2580R in the direction of the arrow shown in the diagram.

[0512] Furthermore, the touch sensor 2595 is located on the circuit board 2510 side of the display device 2501. .

[0513] The adhesive layer 2597 is located between substrate 2510 and substrate 2590 and touches the display device 2501. Attach the Chisensa 2595.

[0514] As shown in Figures 29(A) and (B), the light emitted from the light-emitting eleme...

Claims

1. A light-emitting element having a light-emitting layer, The light-emitting layer comprises a first organic compound, a second organic compound, and a guest material. The first organic compound has a nitrogen-containing six-membered heteroaromatic skeleton, A light-emitting element in which the content of an organic compound containing a pyrrole skeleton having an NH group in the light-emitting layer is 0.01 or less by weight relative to the second organic compound.

2. A light-emitting element having a light-emitting layer, The light-emitting layer comprises a first organic compound, a second organic compound, and a guest material. The first organic compound has at least one of a pyridine skeleton, a diazine skeleton, or a triazine skeleton. A light-emitting element in which the content of an organic compound containing a pyrrole skeleton having an NH group in the light-emitting layer is 0.01 or less by weight relative to the second organic compound.

3. In claim 1 or claim 2, A light-emitting element in which the stabilization energy when the NH bond dissociates in an organic compound containing the pyrrole skeleton having the NH group is less than 0 eV.

4. A light-emitting element having a light-emitting layer, The light-emitting layer comprises a first organic compound, a second organic compound, and a guest material. The first organic compound has a nitrogen-containing six-membered heteroaromatic skeleton, In the light-emitting layer, the content of an organic compound containing a carbasol skeleton having an NH group is 0.01 or less by weight relative to the second organic compound, thus providing a light-emitting element.

5. A light-emitting element having a light-emitting layer, The light-emitting layer comprises a first organic compound, a second organic compound, and a guest material. The first organic compound has at least one of a pyridine skeleton, a diazine skeleton, or a triazine skeleton. A light-emitting element in which the content of an organic compound containing a carbazole skeleton having an NH group in the light-emitting layer is 0.01 or less by weight relative to the second organic compound.

6. In claim 4 or claim 5, A light-emitting element in which the stabilization energy when the NH bond dissociates in an organic compound containing a carbazole skeleton having an NH group is less than 0 eV.

7. In any one of claims 1 to 6, The aforementioned guest material contains iridium, A light-emitting element characterized by the above.

8. A light-emitting element according to any one of claims 1 to 7, A color filter or at least one transistor, A display device.

9. The display device according to claim 8, At least one of the housing or touch sensors, A powerful electronic device.

10. A light-emitting element according to any one of claims 1 to 7, At least one of the housing or touch sensors, A lighting device having the following features.

Images