Light-emitting device

Abstract

To provide a novel light-emitting device having a low power consumption.SOLUTION: A light-emitting device has a first light-emitting element and a second light-emitting element. The first light-emitting element has a first electrode, a second electrode, and a light-emitting layer. The second light-emitting element has the first electrode, a third electrode, and the light-emitting layer. The second electrode consists of only a first conductive film. The third electrode has a second conductive film and a third conductive film. The first electrode has a light reflection function. The second conductive film has the light reflection function and a light transmission function. The first conductive film and the third conductive film have the light transmission function.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] One embodiment of the present invention is a light-emitting device, or a display device, an electronic device, and a lighting device each having the light-emitting device. Regarding the lighting device.

[0002] Note that one embodiment of the present invention is not limited to the above technical fields. The technical field of one aspect of the present invention relates to an article, a method, or a manufacturing method. is a process, machine, manufacture, or composition of matter. Therefore, the technical field of one embodiment of the present invention disclosed in the present specification more specifically relates to Examples of the semiconductor device include a semiconductor device, a display device, a liquid crystal display device, a light-emitting device, a lighting device, a power storage device, a memory device, etc. Examples include devices, methods for driving them, and methods for manufacturing them. . [Background technology]

[0003] In recent years, electroluminescence (EL) The basic structure of these light-emitting devices is as follows: The device has a structure in which a layer containing a light-emitting substance (EL layer) is sandwiched between a pair of electrodes. By applying a voltage between them, light is emitted from the luminescent material.

[0004] Since the above-mentioned light-emitting device is a self-luminous type, a display device using the same has excellent visibility and backlighting. It has the advantage of not requiring a light source and consuming little power. It also has the advantage of having a high response speed.

[0005] In addition, when the above-mentioned light-emitting device is used in a display device, each sub-pixel in a pixel is provided with a different a method of providing an EL layer having a function of emitting light of different colors (hereinafter referred to as a color-by-color method); A common EL layer having a function of, for example, providing white light to the sub-pixels in the pixel is provided, and A method of providing color filters that transmit light of different colors (hereinafter referred to as color filters) There is a method called the filter method.

[0006] The advantage of the color filter method is that the EL layer can be shared among all sub-pixels. In comparison with the separate coating method, the loss of EL layer material is small, and the process required for forming the EL layer is also reduced. This allows the display device to be manufactured at low cost and with high productivity. Next, in the color-by-color method, the EL layer materials of each subpixel are mixed with each other. To prevent this, a margin is required between each sub-pixel, but in the color filter method, this margin is not sufficient. Therefore, it is necessary to realize a display device with higher pixel density and higher resolution.

[0007] The light-emitting device provides a variety of emission colors depending on the type of light-emitting material contained in the EL layer. When considering application to lighting devices, it is necessary to have white or a similar color of light. There is a demand for highly efficient light-emitting devices that can achieve this. Considering this, there is a demand for a highly efficient light emitting device that emits light with high color purity. Light emitting devices for use in these applications are required to consume less power.

[0008] In order to improve the light emission efficiency of a light emitting device, it is necessary to improve the light extraction efficiency from the light emitting device. In order to improve the light extraction efficiency from the light emitting device, The device uses a micro-optical resonator (microcavity) structure that utilizes the resonance effect of light between the Methods for increasing the light intensity at a long distance have been proposed (see, for example, Patent Document 1).

[0009] In addition, as a light-emitting device that emits white light, a device in which a charge generating layer is provided between multiple EL layers ( A new type of element, called a tandem element, has been proposed. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] JP 2012-182127 A Summary of the Invention [Problem to be solved by the invention]

[0011] As a method for manufacturing a full-color display device, the color-coded method uses fine patterns A process is required to deposit the light-emitting layer only on the necessary sub-pixels using a shadow mask having apertures. The precision required to place the shadow mask openings in the desired positions (also called alignment) is essential. In addition, when applying light-emitting layers to the necessary sub-pixels, Since light-emitting substances may be mixed in, the yield in the manufacture of display devices may decrease. In addition, in a display device capable of high-resolution display with high pixel density, The high alignment accuracy required reduces the yield in the manufacture of display devices, There is a problem of increased costs.

[0012] In contrast, in the color filter method, the shadow mask having the above-mentioned fine openings is used. Since no mask is required, the display device can be manufactured with high productivity. In the color filter method, for example, a light-emitting layer that emits white light is formed in common for each sub-pixel. Therefore, the light emitted by each sub-pixel contains not only the desired color but also other colors. Therefore, the color filter method has the problem that the color purity of the light is lower than that of the color-coded method. There is a problem with the low efficiency of light usage.

[0013] Therefore, there is a demand for a light emitting device with excellent productivity. There is also a demand for light-emitting devices with high light utilization efficiency. There is a demand for light emitting devices that provide light with high efficiency.

[0014] Therefore, one object of one embodiment of the present invention is to provide a light-emitting device with high emission efficiency. Another embodiment of the present invention is to provide a light-emitting device with reduced power consumption. Another object of the present invention is to provide a method for manufacturing a semiconductor device having a relatively small number of deposition steps. Another object of the present invention is to provide a light-emitting device having high color purity. Another object of the present invention is to provide a light-emitting device that emits color light. Another object of the present invention is to provide a light-emitting device with high reproducibility. Another object of the present invention is to provide a novel light-emitting device. An object of the present invention is to provide a display device.

[0015] Note that the above description of the object does not preclude the existence of other objects. It is not necessary to solve all of these problems. Problems other than those mentioned above can be solved by the description of the specification, etc. It is obvious from the description of the specification, etc. that other problems can be extracted. do. [Means for solving the problem]

[0016] One embodiment of the present invention is a light-emitting device having a plurality of light-emitting elements having different electrode structures. A light emitting device having a microcavity structure and a light emitting device not having a microcavity structure The light emitting device has a light emitting element.

[0017] Another embodiment of the present invention is a light-emitting device including a first light-emitting element and a second light-emitting element. The first light-emitting element has a first electrode, a second electrode, and a first light-emitting layer. The second light-emitting element has a first electrode, a third electrode, and a first light-emitting layer, and the second electrode is The third electrode is made of only the first conductive film, and the third electrode is made of the second conductive film and the third conductive film on the second conductive film. The first electrode has a function of reflecting light, and the second conductive film has a function of reflecting light. The first conductive film and the third conductive film have a function of transmitting light. It is a light-emitting device having a function of transmitting light.

[0018] In the above configuration, the first light-emitting element emits light having wavelengths in the blue wavelength region, the green wavelength region, and the yellow wavelength region. and the red wavelength region. The second light emitting element has a function of emitting light in a blue wavelength region, a green wavelength region, and a red wavelength region. It is preferable that the optical fiber has a function of exhibiting light emission having an emission spectrum peak in any one of the above ranges. .

[0019] Another embodiment of the present invention is a light-emitting element including a first light-emitting element, a second light-emitting element, and a third light-emitting element. and a fourth light-emitting element, the first light-emitting element having a first electrode and The second light-emitting element has a second electrode, a first light-emitting layer, and a second light-emitting layer. the third light emitting element has a first electrode, a third electrode, a first light emitting layer, and a second light emitting layer; a fourth light-emitting element having a first electrode, a fourth electrode, a first light-emitting layer, and a second light-emitting layer; The device has a first electrode, a fifth electrode, a first light-emitting layer, and a second light-emitting layer. The first electrode is made of only the first conductive film, and the third electrode is made of the second conductive film and the second conductive film. The fourth electrode has a second conductive film and a fourth conductive film on the second conductive film. and the fifth electrode has a second conductive film and a fifth conductive film on the second conductive film. The third conductive film has a region that is thicker than the fourth conductive film, and the first electrode has a function of reflecting light. The second conductive film has a function of reflecting light and a function of transmitting light, and the first conductive film has a function of reflecting light and a function of transmitting light. The conductive film, the third conductive film, the fourth conductive film, and the fifth conductive film are light-transmitting films. It is an optical device.

[0020] In the above structure, the fourth conductive film has a region that is thicker than the fifth conductive film, and the first The conductive film preferably has a region that is thicker than the fifth conductive film.

[0021] In each of the above configurations, the distance between the first electrode and the first conductive film, the distance between the first electrode and the third a distance between the first electrode and the fourth conductive film, a distance between the first electrode and the fifth conductive film, It is preferable that the distances are equal to each other.

[0022] Another embodiment of the present invention is a light-emitting element including a first light-emitting element, a second light-emitting element, and a third light-emitting element. and a fourth light-emitting element, the first light-emitting element having a first electrode and a second electrode, a first carrier injection layer on the second electrode, a first light emitting layer, and a second light emitting layer. and the second light-emitting element has a first electrode, a third electrode, and a second cap on the third electrode. The third light emitting element has a carrier injection layer, a first light emitting layer, and a second light emitting layer. an electrode, a third electrode, a third carrier injection layer on the third electrode, a first light emitting layer, and a second and a fourth light-emitting element having a first electrode, a third electrode, and a second light-emitting layer on the third electrode. a fourth carrier injection layer, a first light emitting layer, and a second light emitting layer; and a second electrode The third electrode is made of only the first conductive film, and the third electrode is made of the second conductive film and the third conductive film on the second conductive film. a film, the second carrier injection layer having a region thicker than the third carrier injection layer, The first electrode has a function of reflecting light, and the second conductive film has a function of reflecting light and a function of transmitting light. The first conductive film and the third conductive film have a function of transmitting light. It is an optical device.

[0023] In the above-mentioned configuration, the third carrier injection layer has a region thicker than the fourth carrier injection layer. The sum of the thicknesses of the first conductive film and the first carrier injection layer is It is preferable that the thickness is thicker than the sum of the thicknesses of the injection layers.

[0024] In each of the above configurations, the distance between the first electrode and the first carrier injection layer, the first electrode a distance between the first electrode and the second carrier injection layer, a distance between the first electrode and the third carrier injection layer, and It is preferable that the first electrode and the fourth carrier injection layer have regions with equal distances from each other.

[0025] In each of the above structures, the first carrier injection layer, the second carrier injection layer, the third carrier injection layer, The first carrier injection layer and the fourth carrier injection layer preferably include a metal oxide.

[0026] In each of the above configurations, the first light emitting element emits light having wavelengths in the blue wavelength region, green wavelength region, and yellow wavelength region. A light emitting device having an emission spectrum peak in at least one of the color wavelength region and the red wavelength region. The second light-emitting element has a function of emitting light, and the second light-emitting element has an emission spectrum peak in the red wavelength region. The third light-emitting element has a function of emitting light having an emission spectrum peak in the green wavelength region. The fourth light-emitting element has a function of emitting light having an emission spectrum in the blue wavelength region. It is preferable that the photosensitive resin has a function of exhibiting light emission having a peak.

[0027] In each of the above configurations, the first light-emitting element, the second light-emitting element, the third light-emitting element, and The fourth light-emitting element further has a charge generating layer between the first light-emitting layer and the second light-emitting layer. This is preferable.

[0028] In each of the above configurations, the first light-emitting element, the second light-emitting element, the third light-emitting element, and The fourth light-emitting element preferably further includes a third light-emitting layer. It is preferable that the light-emitting layer 3 has a contact area.

[0029] In each of the above configurations, the second conductive film is made of a metal having a thickness of 1 nm to 30 nm. It is preferable that the second conductive film contains Ag.

[0030] In each of the above configurations, the first conductive film, the third conductive film, the fourth conductive film, and the fifth conductive film The conductive film preferably contains a metal oxide or an organic conductor. The first conductive film, the fourth conductive film, and the fifth conductive film each contain at least one of In and Zn. It is preferable to have

[0031] In each of the above configurations, the first electrode preferably includes a metal. The poles preferably comprise at least one of Ag and Al.

[0032] Another embodiment of the present invention is a light-emitting device having any of the above structures, and a color filter or a transistor. Another aspect of the present invention is a display device comprising the The electronic device has a display device and at least one of a housing and a touch sensor. Another aspect of the present invention is a light-emitting device having any of the above structures and at least one of a housing and a touch sensor. Another embodiment of the present invention is a lighting device having a light-emitting element. In addition, electronic devices having light-emitting elements are also included in the scope of the present invention. An optical device refers to an image display device or a light source (including a lighting device). Also, a light-emitting device Connectors, such as FPC (Flexible printed circuit), Display module with TCP (Tape Carrier Package) attached , a display module with a printed wiring board at the end of the TCP, or a light-emitting element with a COG ( A display module with IC (integrated circuit) directly mounted using the Chip On Glass method. The modules may also include light emitting devices. Effect of the Invention

[0033] According to one embodiment of the present invention, a light-emitting device with high emission efficiency can be provided. According to one embodiment of the present invention, a light-emitting device with reduced power consumption can be provided. According to one embodiment of the present invention, a light emitting device that can be easily manufactured with a relatively small number of film formation steps can be provided. Alternatively, according to one embodiment of the present invention, a light-emitting device that emits light with high color purity can be provided. Alternatively, in one embodiment of the present invention, a light-emitting device with high color reproducibility can be provided. According to one embodiment of the present invention, a novel light-emitting device can be provided. In one aspect, a novel display device can be provided.

[0034] Note that the description of these effects does not preclude the existence of other effects. It is not necessary to have all of these effects. Effects other than these are described in the specification. The disclosure of the specification, drawings, claims, etc. is self-evident, and the disclosure of the specification, drawings, claims, etc. is self-evident. From this, it is possible to extract other effects. [Brief description of the drawings]

[0035] [Figure 1] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Diagram 2] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Diagram 3] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Figure 4] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Diagram 5] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Figure 6] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Figure 7] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Figure 8] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Figure 9] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Figure 10] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Figure 11] 1 is a schematic cross-sectional view of a light-emitting device according to one embodiment of the present invention. [Figure 12] 1A to 1C are schematic cross-sectional views illustrating a method for manufacturing a light-emitting device according to one embodiment of the present invention. [Figure 13] 1A to 1C are schematic cross-sectional views illustrating a method for manufacturing a light-emitting device according to one embodiment of the present invention. [Figure 14]1A and 1B are schematic cross-sectional views of a light-emitting element of one embodiment of the present invention and a diagram illustrating the correlation between energy levels of a light-emitting layer. [Figure 15] 1A and 1B are schematic cross-sectional views of a light-emitting element of one embodiment of the present invention and a diagram illustrating the correlation between energy levels of a light-emitting layer. [Figure 16] 1A and 1B are schematic cross-sectional views of a light-emitting element of one embodiment of the present invention and a diagram illustrating the correlation between energy levels of a light-emitting layer. [Figure 17] 1A and 1B are a top view and a cross-sectional schematic diagram illustrating a display device of one embodiment of the present invention. [Figure 18] 1A and 1B are schematic cross-sectional views illustrating a display device according to one embodiment of the present invention. [Figure 19] 1A and 1B are schematic cross-sectional views illustrating a display device according to one embodiment of the present invention. [Figure 20] 1A to 1C are schematic cross-sectional views illustrating a method for producing an EL layer. [Figure 21] FIG. 2 is a conceptual diagram illustrating a droplet ejection device. [Figure 22] 1A and 1B are a block diagram and a circuit diagram illustrating a display device of one embodiment of the present invention. [Diagram 23] FIG. 1 is a circuit diagram illustrating a pixel circuit of a display device according to one embodiment of the present invention. [Figure 24] FIG. 1 is a circuit diagram illustrating a pixel circuit of a display device according to one embodiment of the present invention. [Diagram 25] FIG. 1 is a perspective view illustrating an example of a touch panel of one embodiment of the present invention. [Figure 26] 1 is a cross-sectional view illustrating an example of a display device and a touch sensor according to one embodiment of the present invention. [Figure 27] FIG. 1 is a cross-sectional view illustrating an example of a touch panel of one embodiment of the present invention. [Figure 28] 1A and 1B are a block diagram and a timing chart of a touch sensor according to one embodiment of the present invention. [Figure 29] FIG. 1 is a circuit diagram of a touch sensor according to one embodiment of the present invention. [Diagram 30] 1A to 1C illustrate a structure of a display device according to one embodiment of the present invention. [Diagram 31] FIG. 1 is a cross-sectional view illustrating a structure of a display device according to one embodiment of the present invention. [Diagram 32] FIG. 2 illustrates a pixel circuit of a display device according to one embodiment of the present invention. [Diagram 33] 1A to 1C illustrate a structure of a display device according to one embodiment of the present invention. [Diagram 34] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Diagram 35] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Diagram 36] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 37] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 38] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 39] FIG. 1 is a perspective view illustrating a display device according to one embodiment of the present invention. [Diagram 40] 1A and 1B are a perspective view and a cross-sectional view illustrating a light-emitting device of one embodiment of the present invention. [Diagram 41] FIG. 1 is a cross-sectional view illustrating a light-emitting device according to one embodiment of the present invention. [Diagram 42] 1A to 1C illustrate a lighting device and an electronic device according to one embodiment of the present invention. [Diagram 43] 1A to 1C are diagrams illustrating a lighting device according to one embodiment of the present invention. [Diagram 44] 1 is a schematic cross-sectional view illustrating a light-emitting element according to an embodiment. [Diagram 45] FIG. 13 is a graph showing luminance-current density characteristics of a light-emitting element in the example. [Figure 46] FIG. 13 is a graph showing luminance-current density characteristics of a light-emitting element in the example. [Figure 47] FIG. 13 is a graph showing current density-voltage characteristics of a light-emitting element in the example. [Figure 48] FIG. 13 is a graph showing current density-voltage characteristics of a light-emitting element in the example. [Figure 49] FIG. 13 is a graph showing current efficiency vs. luminance characteristics of a light-emitting element in the embodiment. [Figure 50] FIG. 13 is a graph showing current efficiency vs. luminance characteristics of a light-emitting element in the embodiment. [Figure 51] FIG. 2 is a graph showing electroluminescence spectra of light-emitting elements according to an embodiment of the present invention. [Figure 52]FIG. 2 is a graph showing electroluminescence spectra of light-emitting elements according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] Hereinafter, the embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the above description, and the embodiments and details thereof are not limited to those described above without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the embodiments described below. The terms of the present disclosure are not to be construed as being limited to the content.

[0037] In addition, the position, size, range, etc. of each component shown in the drawings are not necessarily shown in order to facilitate understanding. The actual position, size, range, etc. may not be shown. The present invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings, etc.

[0038] In addition, in this specification, ordinal numbers such as 1st, 2nd, etc. are used for convenience. In some cases, the order of steps or layers may not be indicated. For example, "first" may be replaced with "second" or " " can be appropriately replaced with "the third" etc. The ordinal numbers used to identify an aspect of the present invention may not match those used in the present invention. be.

[0039] In addition, in this specification and the like, when explaining the configuration of the invention using drawings, The reference numerals may be commonly used among different drawings.

[0040] In addition, in this specification and the like, the terms "film" and "layer" are interchangeable. For example, the term "conductive layer" can be changed to the term "conductive film." Alternatively, for example, the term "insulating film" may be changed to "insulating layer." It may be possible to change the term to:

[0041] In the present specification and the like, the singlet excited state refers to a singlet state having an excitation energy. In addition, the lowest singlet excited energy level (S1 level) is the lowest The excited energy level of the singlet excited state (S1 state). Also, the triplet excited state is a triplet state with an excited energy. The lowest level (T1 level) of In this specification and the like, the term "singlet excited state" and "singlet excited energy" are used interchangeably. Even when written as "energy level," it may refer to the S1 state and S1 level. In addition, even when the triplet excited state and triplet excited energy level are expressed, the T1 state It may represent the T1 state and the T2 level.

[0042] In the present specification and the like, a fluorescent material is a material that, when relaxed from a singlet excited state to a ground state, A material that emits light in the visible light region. Phosphorescent materials are materials that relax from a triplet excited state to a ground state. When combined with a phosphorescent material, it emits light in the visible light region at room temperature. is one of the materials that can convert triplet excitation energy into visible light.

[0043] In this specification and the like, room temperature refers to any temperature between 0°C and 40°C.

[0044] Color is generally defined as hue (corresponding to the wavelength of monochromatic light), saturation (vividness, i.e., whiteness) and It is defined by three elements: lightness (the degree to which light is not visible) and brightness (the brightness or intensity of light). In this specification, color refers to any one of the above three elements or any In addition, in this specification, the two lights may be different in color. The difference between the two means that at least one of the three elements above is different. This also includes differences in the shape of the spectrum of the light or the distribution of the relative intensities of each peak.

[0045] In this specification, the blue wavelength region refers to a wavelength of 400 nm or more and less than 480 nm. The blue emission has at least one emission spectrum peak in the wavelength region. The green wavelength region is the wavelength region of 480 nm or more and less than 550 nm. The emission of the yellow wavelength has at least one emission spectrum peak in the wavelength region. The long region is the wavelength region of 550 nm or more and less than 600 nm, and yellow light is emitted in this wavelength region. The red wavelength region has at least one emission spectrum peak in the 600 The wavelength range is from 740 nm to 740 nm, and the red emission is at least one It has an emission spectrum peak.

[0046] (Embodiment 1) In this embodiment, a light-emitting device according to one embodiment of the present invention will be described below with reference to FIGS. explain.

[0047] <Light-emitting device configuration example 1> First, a structure of a light-emitting device according to one embodiment of the present invention will be described below with reference to FIG.

[0048] FIG. 1 is a schematic cross-sectional view of a light-emitting device 150 according to one embodiment of the present invention.

[0049] The light emitting device 150 includes a light emitting element 221W and a light emitting element 221 on a substrate 200. do.

[0050] The light-emitting element 221W includes an electrode 101, an electrode 102, and an EL element provided between the electrodes. The light-emitting element 221 includes an electrode 101, an electrode 103, and a layer 100 between the electrodes. The EL layer 100 is provided on the electrode 102. The electrode 102 has a conductive film, and the electrode 103 The EL layer 100 includes a conductive film 104 and a conductive film 106. It has an optical layer 130.

[0051] In addition to the light-emitting layer 130, the EL layer 100 shown in FIG. It has functional layers such as layer 112 , an electron transport layer 118 , and an electron injection layer 119 .

[0052] In this embodiment, the electrode 101 is a cathode, and the electrodes 102 and 103 are However, the configuration of the light emitting device 150 is not limited to this. The electrode 101 is an anode, the electrodes 102 and 103 are cathodes, and the EL layer 100 is laminated as follows: The order may be reversed. That is, from the anode side, a hole injection layer, a hole transport layer, and a light emitting layer are The electron transport layer and the electron injection layer may be stacked in this order.

[0053] The configuration of the EL layer 100 is not limited to the configuration shown in FIG. At least one selected from the group consisting of the transport layer 112, the electron transport layer 118, and the electron injection layer 119. Alternatively, the EL layer 100 may have a structure in which carriers (holes or electrons) Reduce the injection barrier of the carrier (hole or electron), improve the transportability of the carrier ( It is possible to inhibit the transport of electrons (holes or electrons) or suppress the quenching phenomenon caused by the electrode. The functional layers may each be a single layer. Alternatively, a configuration in which multiple layers are laminated may be used.

[0054] In FIG. 1, a hole injection layer 111, a hole transport layer 112, a light emitting layer 130, an electron transport The layer 118, the electron injection layer 119, and the electrode 101 are separated for each light emitting element. However, the light emitting element can be used in common without being separated for each light emitting element.

[0055] In the light-emitting device 150 according to one embodiment of the present invention, a pair of electrodes (electrode 1) of the light-emitting element 221W 01 and electrode 102), and a pair of electrodes (electrode 101 and electrode 103) of the light-emitting element 221 By applying a voltage between the cathode and the anode, electrons flow from the cathode and holes flow from the anode. The injected carriers (electrons and holes) are injected into the EL layer 100, causing a current to flow. ) recombine to form an exciton. When carriers (electrons and holes) recombine and form excitons, the light-emitting layer 130 becomes active. The light-emitting material is excited, and light is emitted from the light-emitting material.

[0056] The light-emitting layer 130 may be purple, blue, blue-green, green, yellow-green, yellow, yellow-orange, orange, or red. It is preferable that the light-emitting element contains one or more light-emitting materials that emit light of different colors.

[0057] The light-emitting layer 130 may be configured by stacking two layers. The first compound and the second compound are two types of luminescent materials that have the function of exhibiting different colors. By using each of them, it is possible to obtain multiple lights simultaneously. It is preferable to select a light-emitting material for the light-emitting layer so that the light emitted is white or close to white. .

[0058] The light-emitting layer 130 may have a structure in which three or more layers are laminated, and may not have a light-emitting material. It may include layers.

[0059] The electrode 101 has a function of reflecting visible light. The conductive film 106 has a function of transmitting visible light. Therefore, the electrode 102 has a function of transmitting visible light and a function of transmitting visible light. The electrode 103 has a function of reflecting and transmitting visible light.

[0060] Therefore, the light emitted by the light emitting element 221W and the light emitting element 221 is guided by the electrodes 102 and The light is emitted to the outside through the electrode 103. That is, the light emitting device 150 is a bottom emission type (bottom emission type). However, one embodiment of the present invention is not limited to this. A double-sided emission type ( The light emitting device may be of the dual emission type.

[0061] Moreover, the light emitting element 221 has a microcavity structure.

[0062] <Microcavity structure> The light emitted from the light-emitting layer 130 resonates between a pair of electrodes (electrode 101 and electrode 103). In addition, the light emitting layer 130 is arranged at a position where the intensity of light of a desired wavelength is increased among the emitted light. For example, the optical distance from the reflective area of ​​the electrode 101 to the light emitting area of ​​the light emitting layer 130 is and the optical distance from the reflective area of ​​the electrode 103 to the light emitting area of ​​the light emitting layer 130. This makes it possible to increase the intensity of light of a desired wavelength among the light emitted from the light emitting layer 130. can.

[0063] The optical distance from the reflection area of ​​the electrode 101 to the light-emitting area of ​​the light-emitting layer 130 is It is expressed by the product of the distance from the reflection area of ​​the light emitting layer 130 to the light emitting area of ​​the light emitting layer 130 and the refractive index. The optical distance from the reflective area of ​​the electrode 103 to the light emitting area of ​​the light emitting layer 130 is It is expressed as the product of the refractive index and the distance from the light emitting region to the light emitting region of the light emitting layer 130. In the element 221, the thickness of the conductive film 106 is adjusted to control the amount of light emitted from the light-emitting layer 130. The hole injection layer 111 or the light having a desired wavelength can be enhanced in intensity. At least one of the hole transport layer 112, the electron injection layer 119 or the electron transport layer 1 By adjusting the thickness of at least one of the light emitting layers 130, the light emitted from the light emitting layer 130 can be reduced. In other words, the intensity of light of a desired wavelength may be increased.

[0064] For example, in the electrodes 101 and 103, the refraction of a conductive film having a function of reflecting light When the refractive index of the light-emitting layer 130 is smaller than that of the conductive film 1 of the electrode 103, The thickness of the film 06 is set so that the optical distance between the electrode 101 and the electrode 103 is approximately mλ / 2 (m is a natural number, λ represents the wavelength of the light to be intensified by the light emitting element 221).

[0065] In addition, when it is difficult to precisely determine the reflection areas of the electrodes 101 and 103, By assuming that any area of ​​the electrode 101 and the electrode 103 is a reflection area, the light emitted from the light-emitting layer 130 can be In addition, the light emitting region of the light emitting layer 130 may be narrowed down to a certain optical distance. When it is difficult to precisely determine the region, an arbitrary region of the light-emitting layer 130 can be assumed to be a light-emitting region. In addition, an optical path that enhances the intensity of the light emitted from the light emitting layer 130 may be derived. In the fine print, the vicinity of λ means −20 nm or more and +20 nm or less with respect to λ.

[0066] The microcavity structure enhances the intensity of light at the desired wavelength, making it possible to produce light-emitting devices. The light emitted from the child 221 is purple, blue, blue-green, green, yellow-green, yellow, yellow-orange, and orange. and red. When the light emitting device 150 is used in a display device, the light emitted from the light emitting element 221 is The light has an emission spectrum peak in any one of the wavelength regions of blue, green, and red. preferable.

[0067] As described above, by providing a microcavity structure and adjusting the optical distance between a pair of electrodes, This suppresses light scattering and absorption in the vicinity of each electrode, and reduces the amount of light with respect to the desired wavelength. The extraction efficiency can be improved. In addition, the intensity of the light of the desired wavelength is increased, resulting in high color reproduction. Light emission with purity can be obtained.

[0068] On the other hand, the electrode 102 of the light emitting element 221W is made of only a conductive film having a function of transmitting light. Therefore, the light emitting device 221W does not have a microcavity structure, and the light emitting layer 130 The light emitted is extracted to the outside without increasing the intensity of light of a specific wavelength. It is possible to efficiently extract white light or light close to white light from the visible light range. In addition, white light or light close to it can be expressed as blue, green, yellow, and red wavelengths. It is preferable that the emission spectrum has at least one peak in the long region.

[0069] Therefore, the light emitting element 221 having a microcavity structure and the light emitting element 222 having a microcavity structure The light emitting device 150 having the light emitting element 221W having no structure can emit light with high color purity and white or It is possible to extract light of a color similar to that of the original with high light extraction efficiency. Therefore, the configuration of the light emitting device 150 provides a light emitting device with high color purity and high luminous efficiency. This can be done.

[0070] In addition, the EL layer 100 of the light emitting element 221 and the EL layer 100 of the light emitting element 221W Therefore, the light emitting device 150 is an easy-to-manufacture light emitting device. It is located.

[0071] In the above structure, the material constituting the conductive film of the electrode 102 and the conductive film 106 is The materials may be the same or different. When the same material is used for the electrode 102 and the conductive film 106, This is preferable because it makes it easier to form a pattern by an etching process. Each of the conductive film and the conductive film 106 may have a structure in which two or more layers are stacked.

[0072] In the light-emitting device 150, the electrode 101 and the conductive film 104 may be made of the same material. Alternatively, different materials may be used. When the same material is used for the electrode 101 and the conductive film 104, This can reduce the manufacturing cost of the light emitting device 150. Each of these may have a structure in which two or more layers are laminated.

[0073] The conductive film 104 is made to have a thickness that allows light to pass through (for example, a thickness of 1 nm to 30 nm). The metals that can be suitably used are silver (Ag) or silver (Ag) By using an alloy having the above structure, it is possible to increase the reflectance of the conductive film 104. Ag is preferable because it can increase the luminous efficiency of the electrons. In addition, Ag has a low absorption rate of light in the visible light region. Therefore, by making the thickness just thick enough to transmit light, the function of transmitting light and the function of reflecting light can be achieved. A reflective film having the above structure can be formed.

[0074] The electrode 101 is made of a material containing aluminum (Al) or silver (Ag). By this, it becomes possible to increase the reflectance of the electrode 101, thereby increasing the light emitting efficiency of the light emitting element. In addition, since Al is a low-cost material and is easy to form a pattern, This is preferable because it can reduce the structural cost of the light-emitting element. In addition, Ag has a particularly high reflectance. Since the compound has the formula (I), the luminous efficiency of the light-emitting element can be increased, which is preferable.

[0075] For the electrode 102 and the conductive film 106, a metal oxide can be suitably used. In addition, the metal oxide is at least one of indium (In) and zinc (Zn). It is preferable that the metal oxide contains In and / or Zn to enhance electrical conductivity. In addition, Zn is a low-cost material, so it is possible to use Zn as a conductive material. By using it for the film, the manufacturing cost of the light-emitting element can be reduced.

[0076] When a material containing Al and an oxide containing In are in direct contact with each other, The difference in ionization tendency between the material and the oxide containing In causes the electron transfer between the materials. There may be cases where an electrode containing this material is electrolytically corroded. It is preferable that the material and the oxide containing In are not in contact with each other. The metal contained in the film 104 is particularly preferably Ag.

[0077] By using the light emitting device 150 as described above in the pixels of a display device, light emission with high color purity can be achieved. It is possible to provide a highly efficient display device. The device can reduce power consumption.

[0078] <Configuration Example 2 of Light Emitting Device> Next, a configuration example different from that of the light emitting device 150 shown in FIG. 1 will be described below with reference to FIG. conduct.

[0079] FIG. 2 is a schematic cross-sectional view illustrating a light-emitting device according to one embodiment of the present invention. The parts having the same functions as those shown in 1 are shown with the same hatch pattern and the reference numbers are omitted. In addition, parts having similar functions are denoted by similar reference numerals, and their detailed explanations will be omitted. may be omitted.

[0080] The light emitting device 152 shown in FIG. 2 includes a light emitting element 221W and a light emitting element 221 R, a light emitting element 221G, and a light emitting element 221B.

[0081] The light emitting element 221W includes an electrode 101, an electrode 102, and an EL layer 10 provided between the electrodes. 0. The light emitting element 221R has an electrode 101, an electrode 103R, and a The light emitting element 221G has an EL layer 100 provided thereon. 03G and an EL layer 100 provided between the electrodes. The device includes an electrode 101, an electrode 103B, and an EL layer 100 provided between the electrodes. The electrode 102 has a conductive film, and the electrode 103R has a conductive film 104 and a conductive film 106R. The electrode 103G has a conductive film 104 and a conductive film 106G, and the electrode 103B has a conductive The EL layer 100 includes at least a light-emitting layer 104 and a conductive layer 106B. The light-emitting layer 130 includes, for example, a light-emitting layer 120 and a light-emitting layer 140 .

[0082] In addition, the EL layer 100 shown in FIG. 2 includes a hole injection layer in addition to the light emitting layer 120 and the light emitting layer 140. 111, a hole transport layer 112, an electron transport layer 118, and an electron injection layer 119. do.

[0083] In FIG. 2, a hole injection layer 111, a hole transport layer 112, a light emitting layer 120, and a light emitting layer 1 40, the electron transport layer 118, the electron injection layer 119, and the electrode 101 are each Although the example is shown in a separated state, the light emitting elements can be used in common without being separated. .

[0084] One of the light-emitting layers 120 and 140 is an emitting layer that emits purple, blue, or blue-green light. It is preferable that the color of the material is one or more selected from the group consisting of green, yellow-green, and the other is selected from the group consisting of green, yellow-green, and the like. Any one selected from the group consisting of light-emitting materials that emit light of red, yellow, yellow-orange, orange, or red. It is preferred to have one or more.

[0085] In addition, either or both of the light-emitting layer 120 and the light-emitting layer 140 may be formed by stacking two layers. The two light-emitting layers may be configured to emit light of different colors, that is, a first compound and a second compound. By using two types of luminescent materials each with a different function, multiple lights can be obtained simultaneously. In particular, the light emitted by the light-emitting layers 120 and 140 can be white or close to white. It is preferable to select the luminescent materials used for the luminescent layer 120 and the luminescent layer 140 so as to obtain a desired color. I wish.

[0086] In addition, either or both of the light-emitting layer 120 and the light-emitting layer 140 may be formed by laminating three or more layers. The light-emitting layer may have a structure including only a light-emitting material, or may include a layer that does not have a light-emitting material.

[0087] The electrode 101 has a function of reflecting visible light. The conductive film 106R, the conductive film 106G, and the conductive film 106B have a function of transmitting visible light. In addition, the conductive film 104 has a function of reflecting and transmitting visible light. The electrode 102 has a function of transmitting visible light, and the electrodes 103R, 103G, and 103B has a function of reflecting and transmitting visible light.

[0088] Therefore, the light emitting element 221W, the light emitting element 221R, the light emitting element 221G, and the light emitting element 2 The light emitted by the electrodes 102, 103R, 103G, and 103C is incident on the electrodes 102, 103C, and 103D. That is, the light emitting device 152 is a bottom emission type (bottom emitter). In FIG. 2, the light emitted from each light emitting element is The three types of light are white or a color close to white (W), red (R), and green (G). ), and blue light (B) are shown diagrammatically by dashed arrows. The same applies to the light-emitting device described later. However, one embodiment of the present invention is not limited thereto. A dual emission type (dual emitter) that emits light from both above and below the substrate 200 on which the optical element is formed. The light emitting device may be of the mission type.

[0089] The light emitting element 221W does not have a microcavity structure, and the light emitting element 221R and the light emitting element The element 221G and the light emitting element 221B have a microcavity structure.

[0090] Due to the microcavity structure, the light emitting element 221R emits light in the red wavelength region. The light emitting element 221G emits light in the green wavelength region, and the light emitting element 221B emits light in the blue wavelength region. The distance between electrode 101 and electrode 103R, the distance between electrode 101 and electrode 103G, It is also preferable to adjust the distance between electrode 101 and electrode 103B.

[0091] In the light emitting element 221R, the thickness of the conductive film 106R is adjusted. In the light emitting element 221B, the thickness of the conductive film 106B is adjusted. By adjusting the above, the amount of light emitted from the light-emitting layer 120 and the light-emitting layer 140 can be adjusted. The optical element can increase the intensity of light of a desired wavelength.

[0092] The conductive film 106R, the conductive film 106G, and the conductive film 106B have different thicknesses. For example, in the electrodes 101, 103R, 103G, and 103B, The refractive index of the conductive film having a function of reflecting light is the refractive index of the light-emitting layer 120 and the light-emitting layer 140. When the thickness of the conductive film 106R of the electrode 103R is smaller than that of the electrode 10 The optical distance between 1 and electrode 103R is m R λ R / 2 neighborhood (m R is a natural number, λ R is a light-emitting element 221R, the wavelength of the light to be intensified is adjusted to be 103G. The thickness of the conductive film 106G is set to a value that the optical distance between the electrode 101 and the electrode 103G is m G λ G / 2 neighborhood (m G is a natural number, λ G represents the wavelength of the light to be intensified by the light emitting element 221G, The thickness of the conductive film 106B of the electrode 103B is adjusted to be equal to that of the conductive film 106B of the electrode 103B. The optical distance between 1 and electrode 103B is m B λ B / 2 neighborhood (m B is a natural number, λ B is a light-emitting element 221B) are adjusted so that

[0093] By using a microcavity structure, the light emitted from the light emitting element 221R is red. The light emitted from the light emitting element 221G has an emission spectrum peak in the wavelength region of green. The light emitted from the light emitting element 221B has an emission spectrum peak in the wavelength region of blue. The light has an emission spectrum peak in the wavelength region.

[0094] As described above, a microcavity structure is provided, and the optical distance between a pair of electrodes of each light-emitting element is By adjusting the amount of light, the scattering and absorption of light in the vicinity of each electrode can be suppressed, and the desired wavelength can be obtained. The light extraction efficiency can be improved. In addition, the intensity of light of a desired wavelength is increased. Therefore, light emission with high color purity can be obtained.

[0095] On the other hand, the electrode 102 of the light emitting element 221W is made of only a conductive film having a function of transmitting light. Therefore, the light emitting element 221W does not have a microcavity structure, and the light emitting layer 120 and In addition, the light emitted by the light emitting layer 140 is extracted to the outside without increasing the intensity of light of a specific wavelength. Therefore, white light or light close to white light in the visible light range can be efficiently transmitted to the outside. In addition, white light or light of a similar color can be extracted using blue, green, yellow, or It is preferable that the light emitting element has an emission spectrum peak in at least one of the red and red wavelength regions.

[0096] Therefore, the light emitting element 221R, the light emitting element 221G, and and a light emitting element 221B having a microcavity structure, and a light emitting element 221W having no microcavity structure. The light emitting device 152 has a high light extraction efficiency of light with high color purity and white or a color close to white. Therefore, the configuration of the light emitting device 152 allows the color purity to be improved. It is possible to provide a light emitting device having high light emitting efficiency.

[0097] In addition, the EL layer 100 of the light emitting element 221R and the EL layer 1 of the light emitting element 221G 00, the EL layer 100 of the light-emitting element 221B, and the EL layer 1 00 can be formed in the same process. Therefore, the light emitting device 152 is an easy-to-manufacture light emitting device. It is an optical device.

[0098] In the above configuration, the conductive film of the electrode 102, the conductive film 106R, and the conductive film 10 The materials constituting the conductive film 106G and the conductive film 106B may be the same as each other or different. The conductive film of the electrode 102, the conductive film 106R, the conductive film 106G, and When the same material is used for the conductive film 106B, the electrodes 102, 103R, 103G, and This makes it easier to form a pattern by an etching process in the process of forming the electrode 103B. In addition, the conductive film of the electrode 102, the conductive film 106R, the conductive film 106G, and the conductive film The conductive film 106B may have a structure in which two or more layers are laminated.

[0099] In the light-emitting device 152, the electrode 101 and the conductive film 104 may be made of the same material. Alternatively, different materials may be used. When the same material is used for the electrode 101 and the conductive film 104, This can reduce the manufacturing cost of the light emitting device 152. Each of these may have a structure in which two or more layers are laminated.

[0100] By using the light emitting device 152 as described above for the pixels of a display device, it is possible to obtain light with high color purity. A highly efficient display device can be provided. The device can reduce power consumption.

[0101] For other configurations of the light emitting device 152, refer to the configuration of the light emitting device 150. That's good.

[0102] <Light-emitting device configuration example 3> Next, a configuration example different from that of the light emitting device 152 shown in FIG. 2 will be described with reference to FIGS. 3 and 4. The explanation is given below.

[0103] 3 and 4 are schematic cross-sectional views showing a light-emitting device according to one embodiment of the present invention. In FIG. 4, the same hatchbacks are used for the parts having the same functions as those in FIG. 1 and FIG. In addition, parts with similar functions are designated with similar symbols. In some cases, detailed explanations of the components will be omitted.

[0104] The light emitting device 154 shown in FIG. 3 and the light emitting device 156 shown in FIG. The light emitting element 221R includes a light emitting element 221G, and a light emitting element 221B. do.

[0105] The light emitting element 221W includes an electrode 101, an electrode 102, and a plurality of light emitting elements provided between the electrodes. The light emitting element 2 has a light emitting unit 208 and a light emitting unit 210. 21R is an electrode 101, an electrode 103R, and a plurality of light-emitting units ( The light emitting element 221G has a light emitting unit 208 and a light emitting unit 210. An electrode 101, an electrode 103G, and a plurality of light-emitting units (light-emitting units) provided between the electrodes. The light emitting element 221B has an electrode 101. and an electrode 103B and a plurality of light-emitting units (light-emitting units 208 and and a light emitting unit 210). The electrode 102 preferably has a similar structure to the EL layer 100. The electrode 103R has a conductive film having a function of reflecting visible light and a function of transmitting visible light. and a conductive film 106R having a function of transmitting visible light. The electrode 103G includes a conductive film 104 having a function of reflecting and transmitting visible light, The electrode 103B has a conductive film 106G that has a function of transmitting visible light. A conductive film 104 having a function of transmitting and a function of transmitting visible light, and membrane 106B.

[0106] In the light emitting device 154 and the light emitting device 156, the light emitting unit 208 and the light emitting unit The light-emitting unit 208 and the light-emitting unit 210 are laminated. A charge generating layer 115 is provided.

[0107] Light-emitting unit 208 has light-emitting layer 120, and light-emitting unit 210 has light-emitting layer 140. In addition to the light-emitting layer 120, the light-emitting unit 208 includes a hole injection layer 111, a hole transport layer The light-emitting unit 2 has a light-emitting layer 112, an electron transport layer 113, and an electron injection layer 114. In addition to the light-emitting layer 140, the semiconductor device 10 includes a hole injection layer 116, a hole transport layer 117, and an electron transport layer 118. , and an electron injection layer 119 .

[0108] The charge generating layer 115 sandwiched between the light emitting unit 208 and the light emitting unit 210 is, for example, When a voltage is applied between the electrode 101 and the electrode 102, electrons are injected into one of the light-emitting units, It is sufficient if the electrode 1 injects holes into the other light-emitting unit. When a voltage is applied so that the potential of electrode 02 is higher than the potential of electrode 101, a charge is generated. Layer 115 injects electrons into light-emitting unit 208 and holes into light-emitting unit 210. .

[0109] In addition, as in the case of the light-emitting unit 210, the surface of the light-emitting unit on the anode side is connected to the charge generating layer 115. When in contact with the charge generating layer 115, the charge generating layer 115 acts as a hole injection layer or a hole transport layer for the light emitting unit. Since the light-emitting unit can also play a role in the formation of the hole injection layer or the hole transport layer, the light-emitting unit does not need to be provided with a hole injection layer or a hole transport layer. Alternatively, as in the case of the light-emitting unit 208, the surface of the cathode side of the light-emitting unit may be a charge generating surface. When the charge generating layer 115 is in contact with the green layer 115, the charge generating layer 115 is the electron injection layer or Since it can also play the role of an electron transport layer, the light-emitting unit can also include an electron injection layer or an electron transport layer. A configuration without a transmission layer may also be used.

[0110] 3 and 4, a light emitting element having two light emitting units will be described. However, the same can be applied to a light-emitting element having three or more stacked light-emitting units. As shown in the light emitting device 154 and the light emitting device 156, a plurality of light emitting devices are disposed between a pair of electrodes. By separating the units with charge generating layers, high brightness emission is achieved while keeping the current density low. It is possible to realize light emitting elements with long life. It can be achieved.

[0111] The light-emitting device 154 and the light-emitting device 156 each have an electrode 101, an electrode 102, and an electrode 103R, electrode 103G, electrode 103B, hole injection layers 111 and 116, and hole transport layers 112, 117, light-emitting layer 120, light-emitting layer 140, electron transport layers 113, 118, The electron injection layers 114 and 119 are formed by interposing the electrode 101 and the electrode 102 of the light-emitting device 152, Electrode 103R, electrode 103G, electrode 103B, hole injection layer 111, and hole transport layer 1 12, an emissive layer 120, an emissive layer 140, an electron transport layer 118, and an electron injection layer 119, They each have similar functions, and therefore, detailed descriptions thereof will be omitted.

[0112] The light emitting element 221W is a light emitting element that does not have a microcavity structure. The element 221R, the light emitting element 221G, and the light emitting element 221B have a microcavity structure. It is a light emitting element having the above structure.

[0113] Due to the microcavity structure, the light emitting element 221R emits light in the red wavelength region. The light emitting element 221G emits light in the green wavelength region, and the light emitting element 221B emits light in the blue wavelength region. The distance between electrode 101 and electrode 103R, the distance between electrode 101 and electrode 103G, It is preferable to adjust the distance between the electrode 101 and the electrode 103B. As in the light emitting device 154 shown in FIG. 3, the thickness of the conductive film 106R is thicker than that of the conductive film 106G. It is preferable that the conductive film 106G has a region where it is thicker than the conductive film 106B. Alternatively, as in the light emitting device 156 shown in FIG. 4, the thickness of the conductive film 106R is G, and the thickness of the conductive film 106B is thicker than the conductive film 106R. In the light emitting element 221B, the optical distance between the electrode 101 and the electrode 103B is preferably m B λ B / 2 neighborhood (m B is a natural number greater than 2) and the thickness of the conductive film 106B is increased. The light extraction efficiency is reduced due to light scattering or light absorption in the vicinity of the surface of the conductive film 104. This phenomenon, called surface plasmon resonance (SPR), This suppresses the effect of the hologram, also known as hologram sonance, and achieves high light extraction efficiency. Therefore, blue light can be efficiently extracted from the light emitting element 221B. This becomes possible.

[0114] Light emitting element 221R, light emitting element 221G, and light emitting element having a microcavity structure A light-emitting device 1 having a light-emitting element 221B and a light-emitting element 221W having no microcavity structure. The light emitting device 54 and the light emitting device 156 can emit light with high color purity and light with white or a color close to white. Therefore, the light emitting device 154 and the light emitting device The configuration of 156 makes it possible to provide a light emitting device with high color purity and high luminous efficiency.

[0115] Other configurations of the light emitting device 154 and the light emitting device 156 are the same as those of the light emitting device 15 0 or the configuration of the light emitting device 152 may be taken into consideration.

[0116] <Light-emitting device configuration example 4> Next, a configuration example different from that of the light emitting device 152 shown in FIG. 2 will be described below with reference to FIG. conduct.

[0117] FIG. 5 is a schematic cross-sectional view illustrating a light-emitting device according to one embodiment of the present invention. The parts having the same functions as those shown in Figs. 1 to 4 are indicated with the same hatch patterns. In addition, parts having similar functions are given similar reference numerals, and their details are described below. Detailed explanations may be omitted.

[0118] The light emitting device 158 shown in FIG. 5 includes a light emitting element 221W and a light emitting element 221 R, a light emitting element 221G, and a light emitting element 221B.

[0119] The light emitting element 221W includes an electrode 101, an electrode 102, and an EL layer 10 provided between the electrodes. 0. The light emitting element 221R has an electrode 101, an electrode 103, and a light emitting element 221R provided between the electrodes. The light emitting element 221G has an EL layer 100 that is sandwiched between an electrode 101 and an electrode 10 The light emitting element 221B has an electrode 3 and an EL layer 100 provided between the electrodes. The device has a light-emitting diode (ELD) 101, an electrode 103, and an EL layer 100 provided between the electrodes. The electrode 02 has a conductive film that transmits visible light, and the electrode 103 has a function of reflecting visible light. a conductive film 104 having a function of transmitting visible light and a function of transmitting visible light; 06. The EL layer 100 also includes at least a light-emitting layer 130. 0 has, for example, a light emitting layer 120 and a light emitting layer 140.

[0120] In addition, the EL layer 100 shown in FIG. 5 includes a hole injection layer in addition to the light emitting layer 120 and the light emitting layer 140. 111, a hole transport layer 112, an electron transport layer 118, and an electron injection layer 119. do.

[0121] The light-emitting device 158 includes an electrode 101, an electrode 102, a conductive film 104, and a hole transport film. The electron transport layer 112, the light emitting layer 120, the light emitting layer 140, the electron transport layer 118, and the electron injection layer 11 9 is a light-emitting device 152 including an electrode 101, an electrode 102, a conductive film 104, and a hole transport layer. The electron transport layer 112, the light emitting layer 120, the light emitting layer 140, the electron transport layer 118, and the electron injection layer 11 9 and 10, respectively, have similar functions, and therefore detailed descriptions thereof will be omitted.

[0122] In addition, the EL layer 100 in the light-emitting element 221W has a hole injection layer 111. The EL layer 100 in the light-emitting element 221R has a hole injection layer 111R. The EL layer 100 in the light-emitting element 221B has a hole injection layer 111G. has a hole injection layer 111B.

[0123] The light emitting element 221W is a light emitting element that does not have a microcavity structure. The light emitting element 221R, the light emitting element 221G, and the light emitting element 221B have a microcavity structure. It is a light-emitting element.

[0124] Due to the microcavity structure, the light emitting element 221R emits light in the red wavelength region. The light emitting element 221G emits light in the green wavelength region, and the light emitting element 221B emits light in the blue wavelength region. It is preferable to adjust the distance between the electrodes 101 and 103 so that the light emitted from the electrodes 101 and 103 is intensified. In the light-emitting element 221R, the thickness of the hole injection layer 111R is adjusted. The thickness of the hole injection layer 111G is adjusted, and in the light emitting element 221B, the thickness of the hole injection layer 111B is adjusted. By adjusting the thickness, the light emitted from the light emitting layer 120 and the light emitting layer 140 can be adjusted. The light emitting element can increase the intensity of light of a desired wavelength. The hole injection layer 111G and the hole injection layer 111B may have different thicknesses. For example, In the electrodes 101 and 103, the refractive index of the conductive film having a function of reflecting light is When the refractive index of the hole injection layer 111R is smaller than that of the light emitting layer 120 and the light emitting layer 140, The film thickness is set to m R λ R / 2 neighborhood (m R is a natural number, λ R and represent the wavelengths of the light to be intensified by the light emitting element 221R, respectively). The thickness of the hole injection layer 111G is set such that the optical distance between the electrode 101 and the electrode 103 is m G λ G / 2 neighborhood (m G is a natural number, λ G represent the wavelength of the light to be intensified by the light emitting element 221G, respectively) The thickness of the hole injection layer 111B is adjusted so that the thickness between the electrode 101 and the electrode 103 is 100 nm. The optical distance is m B λ B / 2 neighborhood (m B is a natural number, λ B is a light wave intensified by the light emitting element 221B. The length of each is adjusted to be:

[0125] By using a microcavity structure, the light emitted from the light emitting element 221R is red. The light emitted from the light emitting element 221G has an emission spectrum peak in the wavelength region of green. The light emitted from the light emitting element 221B has an emission spectrum peak in the wavelength region of blue. The light has an emission spectrum peak in the wavelength region.

[0126] Light emitting element 221R, light emitting element 221G, and light emitting element having a microcavity structure A light-emitting device 1 having a light-emitting element 221B and a light-emitting element 221W having no microcavity structure. 58 is a device that extracts light with high color purity and white or nearly white light with high light extraction efficiency. Therefore, the configuration of the light emitting device 158 allows high color purity and light emission. A light emitting device with high light efficiency can be provided.

[0127] In the above configuration, the hole injection layer 111, the hole injection layer 111R, and the hole injection layer 11 The materials constituting the hole injection layer 111G and the hole injection layer 111B may be the same or different. If the same material is used for these hole injection layers, the manufacturing cost of the light emitting device 158 In addition, one or more of these hole injection layers may be a layered structure of two or more layers. It may be a configuration.

[0128] Other configurations of the light emitting device 158 may be the same as those of the light emitting device 150 or the light emitting device 152. Please refer to the configuration of the above.

[0129] <Configuration Example 5 of Light Emitting Device> Next, examples of configurations different from the light emitting device 158 shown in FIG. 5 will be described below with reference to FIGS. 6 and 7. explain.

[0130] 6 and 7 are schematic cross-sectional views showing a light-emitting device according to one embodiment of the present invention. In FIG. 7, the same hatchbacks are used for the parts having the same functions as those in FIG. 1 to FIG. In addition, parts with similar functions are designated with similar symbols. In some cases, detailed explanations of the components will be omitted.

[0131] The light emitting device 160 shown in FIG. 6 and the light emitting device 162 shown in FIG. 221W, light emitting element 221R, light emitting element 221G, and light emitting element 221B. .

[0132] The light emitting element 221W includes an electrode 101, an electrode 102, and a plurality of light emitting elements provided between the electrodes. The light emitting unit 208 and the light emitting unit 210 are also included. The element 221R includes an electrode 101, an electrode 103, and a plurality of light-emitting units provided between the electrodes. The light emitting element 221G also includes a light emitting unit 208 and a light emitting unit 210. The light emitting device includes an electrode 101, an electrode 103, and a plurality of light emitting units (light emitting units) provided between the electrodes. The light emitting element 221B has an electrode 10. 1, an electrode 103, and a plurality of light-emitting units (light-emitting units 208 and The electrode 102 has a function of transmitting visible light. The electrode 103 has a conductive film having a function of reflecting and transmitting visible light. The light-transmitting element includes a conductive film 104 and a conductive film 106 having a function of transmitting visible light.

[0133] In the light emitting device 160 and the light emitting device 162, the light emitting unit 208 and the light emitting unit The light-emitting unit 208 and the light-emitting unit 210 are laminated. A charge generating layer 115 is provided.

[0134] Light-emitting unit 208 has light-emitting layer 120, and light-emitting unit 210 has light-emitting layer 140. In addition to the light-emitting layer 120, the light-emitting unit 208 includes a hole injection layer 111, a hole transport layer The light-emitting unit 2 has a light-emitting layer 112, an electron transport layer 113, and an electron injection layer 114. In addition to the light-emitting layer 140, the semiconductor device 10 includes a hole injection layer 116, a hole transport layer 117, and an electron transport layer 118. , and an electron injection layer 119 .

[0135] The light emitting device 160 and the light emitting device 162 each have an electrode 101, an electrode 102, and an electrode 103, hole transport layers 112 and 117, light emitting layer 120, light emitting layer 140, and electron transport layer The electron injection layers 113 and 118 and the electron injection layers 114 and 119 are connected to the electrode 101 of the light emitting device 158. , an electrode 102, an electrode 103, a hole transport layer 112, a light emitting layer 120, and a light emitting layer 140. The electron transport layer 118 and the electron injection layer 119 have the same functions. Therefore, detailed description thereof will be omitted.

[0136] The light emitting element 221W is a light emitting element that does not have a microcavity structure. The element 221R, the light emitting element 221G, and the light emitting element 221B have a microcavity structure. It is a light emitting element having the above structure.

[0137] Due to the microcavity structure, the light emitting element 221R emits light in the red wavelength region. The light emitting element 221G emits light in the green wavelength region, and the light emitting element 221B emits light in the blue wavelength region. It is preferable to adjust the distance between the electrodes 101 and 103 so that the polarization of the light is enhanced. In the light-emitting device 160 shown in FIG. 6, the thickness of the hole injection layer 111R is The thickness of the hole injection layer 111G is greater than that of the hole injection layer 111B. Alternatively, as in the light-emitting device 162 shown in FIG. The thickness of 1R is thicker than that of hole injection layer 111G, and the thickness of hole injection layer 111B is It is preferable that the region is thicker than the hole injection layer 111R. The optical distance between 101 and electrode 103 is m B λ B / 2 neighborhood (m B is a natural number greater than 2) By increasing the thickness of the hole injection layer 111B, the scattering of light near the surface of the conductive film 104 is reduced. or the effect of surface plasmon resonance, a phenomenon in which the light extraction efficiency decreases due to light absorption. This can suppress the light interference and achieve high light extraction efficiency. From element 221B, blue light can be efficiently extracted.

[0138] By using a microcavity structure, the light emitted from the light emitting element 221R is red. The light emitted from the light emitting element 221G has an emission spectrum peak in the wavelength region of green. The light emitted from the light emitting element 221B has an emission spectrum peak in the wavelength region of blue. The light has an emission spectrum peak in the wavelength region.

[0139] Light emitting element 221R, light emitting element 221G, and light emitting element having a microcavity structure A light-emitting device 1 having a light-emitting element 221B and a light-emitting element 221W having no microcavity structure. The light emitting device 60 and the light emitting device 162 can emit light with high color purity and light with a white color or a color close to white. Therefore, the light emitting device 160 and the light emitting device The configuration of 162 makes it possible to provide a light emitting device with high color purity and high luminous efficiency.

[0140] In the above configuration, the hole injection layer 111, the hole injection layer 111R, and the hole injection layer 11 The materials constituting the hole injection layer 111G and the hole injection layer 111B may be the same or different. When the same material is used for these hole injection layers, the light emitting device 160 and the light emitting device The manufacturing cost of 162 can be reduced. Note that one or more of these hole injection layers may be two or more layers. The upper layer may be a laminated structure.

[0141] Other configurations of the light emitting device 160 and the light emitting device 162 are the same as those of the light emitting device 154 and the light emitting device 162. The configuration of the light device 156 or the light emitting device 158 may be taken into consideration.

[0142] <Configuration Example 6 of Light Emitting Device> Next, examples of configurations different from the light emitting device 154 shown in FIG. 3 will be described with reference to FIGS. 8 to 10. The following explanation is provided.

[0143] 8 to 10 are schematic cross-sectional views illustrating light-emitting devices according to embodiments of the present invention. In Figs. 1 to 10, the same reference numerals as those in Figs. 1 to 7 denote the same functions. In addition, parts with similar functions are marked with similar symbols. In the following description, detailed explanations of the components will be omitted.

[0144] A light emitting device 250 shown in FIG. 8, a light emitting device 252 shown in FIG. 9, and a light emitting device 253 shown in FIG. 54 is a light emitting element 222W, a light emitting element 222R, and a light emitting element 222G on a substrate 200. and light emitting element 222B.

[0145] The light emitting element 222W includes an electrode 101, an electrode 102, and a plurality of light emitting elements provided between the electrodes. The light emitting element 222R has an electrode 101 and an electrode 103R. The light emitting element 221G has a plurality of light emitting units provided between the electrodes. The light emitting device has a electrode 101, an electrode 103G, and a plurality of light emitting units provided between the electrodes. The light emitting element 221B includes an electrode 101, an electrode 103B, and a plurality of electrodes provided between the electrodes. and a light-emitting unit.

[0146] Also, the light emitting device 250, the light emitting device 252, and the light emitting device 254 include a light emitting layer 120 and a light emitting The light emitting device 250 includes a light emitting layer 140, a light emitting device 252, and a light emitting device 254. In addition to the light-emitting layer 120 and the light-emitting layer 140, the layer includes a hole injection layer 111, a hole transport layer 112, an electron Transport layer 113, electron injection layer 114, charge generation layer 115, hole injection layer 116, hole transport layer 1 17 , an electron transport layer 118 , and an electron injection layer 119 .

[0147] The light-emitting layer 120 and the light-emitting layer 140 each have a light-emitting material that exhibits a different color. In addition, it is preferable that one or both of the light-emitting layer 120 and the light-emitting layer 140 are, for example, For example, a two-layer structure such as the light-emitting layer 140a and the light-emitting layer 140b may be used. By using two types of luminescent materials that have the function of producing different colors in the luminescent layer, In particular, the light emission from the light-emitting layer 120 and the light-emitting layer 140 can be obtained simultaneously. The luminescent materials used in each luminescent layer are selected so that the color becomes white or close to white when illuminated. It is also preferable that the light-emitting layer 120 or the light-emitting layer 140 is a laminate of three or more layers. The light-emitting layer may have a structure in which a layer having no light-emitting material is formed, or may include a layer having no light-emitting material.

[0148] In addition, the electrode 102 includes a conductive film.

[0149] The electrode 103R includes a conductive film 108, a conductive film 104 in contact with the conductive film 108, and a conductive The electrode 103G has a conductive film 106R in contact with the conductive film 104. 8, a conductive film 104 in contact with the conductive film 108, and a conductive film 106G in contact with the conductive film 104. The electrode 103B includes a conductive film 108 and a conductive film 109 that is in contact with the conductive film 108. The conductive film 104 and the conductive film 106B are disposed on and in contact with the conductive film 104.

[0150] The light emitting device 250, the light emitting device 252, and the light emitting device 254 are bottom-emitting devices. Therefore, the electrodes 102, 103R, 103G, and 103B have a function of transmitting light. It is preferable that the electrode 101 has a function of reflecting light.

[0151] The light emitting device 250, the light emitting device 252, and the light emitting device 254 include a light emitting element 222W, a light emitting element A partition wall 145 is provided between the light emitting element 222R, the light emitting element 222G, and the light emitting element 222B. The partition wall 145 is insulating. The partition wall 145 is provided between the electrode 102, the electrode 103R, and the electrode 103G. The partition wall 145 covers the end of the electrode 103B and has an opening that overlaps with the electrode. By this, the electrodes on the substrate 200 are the electrodes 102, 103R, 103G, and It is possible to separate the electrodes into islands, like the pole 103B.

[0152] The partition wall 145 may be formed using an inorganic or organic material as long as it has insulating properties. The inorganic material may be silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, etc. Examples of the organic material include silicon, aluminum oxide, and aluminum nitride. For example, photosensitive resin materials such as acrylic resin and polyimide resin can be used.

[0153] The silicon oxynitride 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 % or less. Silicon is 25 atomic % or more and 35 atomic % or less, and hydrogen is 0.1 atomic % or more and 10 atomic % or less. The silicon nitride oxide film is a film that contains more nitrogen than oxygen as its composition. It refers to a film with a high content of nitrogen, preferably 55 atomic % to 65 atomic % and 1 % to 20 atomic %, silicon is 25 atomic % to 35 atomic %, hydrogen is 0.1 atomic % This refers to a film containing this element in a concentration range of 10 atomic % or more.

[0154] At this time, the light-emitting layer 120 is at least one selected from the group consisting of purple, blue, and blue-green. By having a light-emitting material that has the function of exhibiting an emission spectrum peak in one wavelength region, The optical element 222B may be configured to emit blue light. At least one wavelength selected from the group consisting of color, yellow-green, yellow, yellow-orange, orange, and red. By having a light-emitting material having a function of exhibiting an emission spectrum peak in the region, the light-emitting element 2 The light emitting element 222G can be configured to emit green light, and the light emitting element 222R can be configured to emit red light. The light emitting device 250, the light emitting device 252, or the light emitting device 254 having such a configuration can be used. By using this in the pixels of a display device, it is possible to manufacture a display device capable of full color display. The thickness of each light-emitting layer may be the same or different. .

[0155] The light emitting device 250 further includes a light emitting element 222R, a light emitting element 222G, and a light emitting element 222R. The optical elements 224R and 224G are arranged in the directions in which the light emitted from B is extracted. , and a substrate 220 having optical elements 224B. The light emitted from each light-emitting element is The light emitted from the light emitting element 222R is emitted to the outside of the light emitting device through the optical element. The light emitted from the light emitting element 222G is output through the optical element 224R. The light emitted from the light emitting element 222B through the element 224G is reflected by the optical element 224B. It is injected through.

[0156] In addition, the optical elements 224R, 224G, and 224B are For example, the optical element 224R has a function of selectively transmitting light of a specific color. The light emitted from the light emitting element 222R through the optical element 221 is red light. The light emitted from the light emitting element 222G via the light emitting element 224G is green light. The light emitted from the light emitting element 222B via the optical element 224B is blue. It becomes a light that

[0157] The optical element 224R, the optical element 224G, and the optical element 224B may include, for example, a colored layer ( Color filters, bandpass filters, multilayer filters, etc. can be used. In addition, a color conversion element can be applied to the optical element. The color conversion element converts incident light into the corresponding color. The color conversion element is an optical element that converts the wavelength of the light into light with a longer wavelength than the wavelength of the light. By using quantum dots, the color reproducibility of the display device can be improved. This can increase color purity.

[0158] In addition, a plurality of optical elements are provided on the optical element 224R, the optical element 224G, and the optical element 224B. Other optical elements may be provided, such as a circular polarizer and an anti-reflection film. The circular polarizing plate can be provided on the side of the display device from which light emitted by the light emitting device is extracted. When the display device is turned on, the light incident from outside the display device is reflected inside the display device and emitted to the outside. In addition, the provision of an anti-reflection film can prevent the reflection on the surface of the display device. This can weaken the external light that penetrates the display device, allowing the light emitted by the display device to be clearly observed. .

[0159] As shown in FIG. 9, a light emitting device 252 may be configured without the optical element 224B. By not providing the optical element 224B, the light extraction efficiency of the light emitting element 222B is improved. As described later, the light emitting element 222B is a microphone cavity. Due to the structure, the light emitted from the light emitting element 222B has an increased intensity of light of a specific wavelength. Therefore, the light has sufficient color purity even without providing the optical element 224B.

[0160] As shown in FIG. 10, the light emitted from the light emitting element 222W is The light emitted from the light emitting element 222W is The light is emitted to the outside of the light emitting device via the optical element 224W. As a result, the light emitted from the light emitting element 222W is closer to white or a desired color. In addition, the contrast ratio of the light emitting device can be increased.

[0161] In addition, in FIG. 8 to FIG. 10, the light emitted from each light emitting element is white or close to white. White light (W), red light (R), green light (G), and blue light In (B), each is shown diagrammatically with a dashed arrow.

[0162] In addition, a light-shielding layer 223 is provided between each optical element. The light-shielding layer 223 is formed to prevent light from entering from adjacent regions. It is to be noted that the light shielding layer 223 may not be provided. stomach.

[0163] The light-shielding layer 223 has a function of suppressing reflection of external light. The light-shielding layer 223 has a function of preventing the color mixture of light emitted from adjacent light-emitting devices. Examples include metals, resins containing black pigments, carbon black, metal oxides, and multiple metal oxides. A composite oxide containing a solid solution of such a material can be used.

[0164] The light emitting element 222W is a light emitting element that does not have a microcavity structure. The element 222R, the light emitting element 222G, and the light emitting element 222B have a microcavity structure. It is preferable that the light emitting element has the following characteristics.

[0165] The light emitted from the light emitting layer 120 and the light emitting layer 140 is guided by a pair of electrodes (for example, the electrode 10 The light emitting layer 120 and the light emitting layer 140 are resonated between the electrode 103 and the electrode 103R. For example, the electrode 101 is formed at a position where the intensity of light of a desired wavelength is increased. The optical distance from the reflection area to the light-emitting area of ​​the light-emitting layer 120 and the light emitted from the reflection area of ​​the electrode 103B are By adjusting the optical distance to the light emitting region of the light emitting layer 120, the light emitted from the light emitting layer 120 can be The intensity of the light reflected by the electrodes 103G and 103R can be increased. The optical distance from the reflection area of ​​the electrode 101 to the light-emitting area of ​​the light-emitting layer 140 is By adjusting the optical distance to the light emitting region of 0, the light emitted from the light emitting layer 140 That is, the intensity of the light emitted from the plurality of light-emitting layers (here, the light-emitting layer 120 and the light-emitting layer 130) can be increased. In the case of a light-emitting device in which the light-emitting layer 120 and the light-emitting layer 140 are laminated, the light It is preferable to optimize the distance.

[0166] For example, light is irradiated to the electrodes 101, 103R, 103G, and 103B. The refractive index of the conductive film having a reflecting function is higher than the refractive index of the light-emitting layer 120 or the light-emitting layer 140. In the case where the thickness of the conductive film 106R of the electrode 103R is smaller than that of the electrode 101, The optical distance between the electrode 103R is m R λ R / 2(m R is a natural number, λ R is light emitting element 222R Similarly, the electrode 103G has The thickness of the conductive film 106G is set to a value that the optical distance between the electrode 103G and the electrode 101 is m G λ G / 2 (m G is a natural number, λ G and represent the wavelength of the light to be intensified by the light emitting element 222G, respectively. Furthermore, the thickness of the conductive film 106B of the electrode 103B is adjusted so as to be different from that of the electrode 103B. The optical distance between pole 101 is m B λ B / 2(m B is a natural number, λ B The light emitting element 222B emits strong light. The wavelengths of light to be received are adjusted to be

[0167] In the above configuration, in the light emitting element 222R, the light emitting element 222G, and the light emitting element 222B, Since the wavelengths of the light to be intensified are different, the optical distances of the light emitting elements are different from each other. .

[0168] By using a microcavity structure, the light emitted from the light emitting element 222R is red. The light emitted from the light emitting element 222G has an emission spectrum peak in the wavelength region of green. The light emitted from the light emitting element 222B has an emission spectrum peak in the wavelength region of blue. The light has an emission spectrum peak in the wavelength region.

[0169] As described above, a microcavity structure is provided, and the optical distance between a pair of electrodes of each light-emitting element is By adjusting the amount of light, the scattering and absorption of light in the vicinity of each electrode can be suppressed, and the desired wavelength can be obtained. The light extraction efficiency can be improved. In addition, the intensity of light of a desired wavelength is increased. Therefore, light emission with high color purity can be obtained.

[0170] Light emitting element 222R, light emitting element 222G, and light emitting element having a microcavity structure A light-emitting device 2 having a light-emitting element 222B and a light-emitting element 222W having no microcavity structure. 50, the light emitting device 252, and the light emitting device 254 emit light with high color purity and white or nearly white light. Therefore, it is possible to extract light of a different color with high light extraction efficiency. The configuration of the light emitting device 250, the light emitting device 252, and the light emitting device 254 provides high color purity and high luminous efficiency. It is possible to provide a high-performance light-emitting device.

[0171] In the above configuration, the conductive film of the electrode 102, the conductive film 106R, and the conductive film 10 It is preferable that the electrode 16G and the conductive film 106B have a function of transmitting light. 02, conductive film 106R, conductive film 106G, and conductive film 106B. The materials may be the same or different.

[0172] In addition, the conductive film 104 preferably has a function of transmitting light and a function of reflecting light. In addition, the electrode 101 preferably has a function of reflecting light.

[0173] In addition, the conductive film 108 is provided with the same conductive film 106R, conductive film 106G, or conductive film 106B. The conductive film 108, the conductive film 106R, and the conductive film 106R may be made of the same material or different materials. The conductive film 106G and the conductive film 106B are made of the same material. If the electrodes 103A and 103B are made of the same conductive material, the patterning can be performed by an etching process. This is preferable because the light emitting device 250, the light emitting device 252, and the light emitting device 2 It is to be noted that the conductive film 108 is a laminate of two or more layers. The configuration may be such that

[0174] Note that the light emitting device 250, the light emitting device 252, and the light emitting device 254 do not include the conductive film 108. It is also possible to adopt a configuration in which no

[0175] The light emitting device 250, the light emitting device 252, and the light emitting device 254 as described above are used as a display device. By using this element, it is possible to provide a display device with high color purity and high luminous efficiency. That is, a display device having the light emitting device 250, the light emitting device 252, or the light emitting device 254 is Power consumption can be reduced.

[0176] Regarding other configurations of the light emitting device 250, the light emitting device 252, and the light emitting device 254, Regarding the configurations of the light emitting device 150, the light emitting device 152, the light emitting device 154, and the light emitting device 156, Please take this into consideration.

[0177] <Light Emitting Device Configuration Example 7> Next, a configuration example different from that of the light emitting device 250 shown in FIG. 8 will be described with reference to FIGS. 11(A) and 11(B). This is explained below.

[0178] FIG. 11(A) is a schematic cross-sectional view illustrating a light-emitting device according to one embodiment of the present invention. In A), the parts having the same functions as those in Figs. 1 to 10 are denoted with the same hatching. In addition, parts with similar functions are labeled with similar symbols. In some cases, reference symbols will be used and detailed descriptions thereof will be omitted.

[0179] The light-emitting device 256 shown in FIG. 11A includes a transistor 240 and a light-emitting element 242 disposed on a substrate 200. The light emitting element 222W, the light emitting element 222R, the light emitting element 222G, and the light emitting element 222B. 1 is a configuration example of a light emitting device.

[0180] The light emitting element 222W is a light emitting element that does not have a microcavity structure. The element 222R, the light emitting element 222G, and the light emitting element 222B have a microcavity structure. It is preferable that the light emitting element has the following characteristics.

[0181] The light emitting element 222R, the light emitting element 222G, and the light emitting element 222B are in a microcavity structure. When the conductive film 106R, the conductive film 106G, and the conductive film 106B have the structure, the conductive film 106R, the conductive film 106G, and the conductive film 106B transmit light. In this case, the conductive film 106R, the conductive film 106G, and the conductive film By adjusting the film thickness of 106B, each light-emitting element (light-emitting element 222R, light-emitting element 222G, The intensity of light of a desired wavelength among the light emitted by the light emitting elements 222A and 222B can be increased.

[0182] In addition, the conductive film 104 preferably has a function of reflecting light and a function of transmitting light. .

[0183] The light emitting device 256 is also provided with a transistor 240 and an electrode 103R. 40 and electrode 103G, and between transistor 240 and electrode 103B, respectively. The optical elements 224R, 224G, and 224B are included. The light emitted from the optical element is emitted to the outside of the light emitting device through each optical element. The light emitted from the light emitting element 222R is emitted through the optical element 224R. The light emitted from the light emitting element 222G is emitted through the optical element 224G and emitted from the light emitting element 222B. The light that is guided through the optical element 224B is then emitted.

[0184] By providing the optical elements on the substrate 200, the thickness of the light emitting device 256 can be reduced. In addition, the manufacturing cost of the light emitting device 256 can be reduced.

[0185] In addition, the electrodes 102, 103R, 103G, and 103B are transistors. The input terminal is electrically connected to the transistor 240 .

[0186] An example of a transistor 240 included in the light-emitting device 256 illustrated in FIG. 11B is a schematic cross-sectional view of the transistor 240.

[0187] The transistor 240 shown in FIG. 11B is, for example, a field effect transistor (FET). The transistor 240 includes a gate electrode 272 on a substrate 200 and A gate insulating layer 274 on the plate 200 and the gate electrode 272, and a semiconductor layer on the gate insulating layer 274 a gate insulating layer 274 and a source electrode 278a on the semiconductor layer 276; and a drain electrode 278b on the gate insulating layer 274 and the semiconductor layer 276. An insulating layer 282 is formed on the transistor 240, an insulating layer 284 is formed on the insulating layer 282, and an insulating layer 28 4 and an insulating layer 286 on the substrate 282.

[0188] The insulating layer 282 has a region in contact with the semiconductor layer 276. For example, the insulating layer 284 can be formed of an oxide insulating material. The insulating layer 284 has a function of suppressing impurities that may enter the insulating layer 240. The insulating layer 286 may be formed of a nitride insulating material. The insulating layer 286 has a function of flattening unevenness caused by the above-mentioned. The insulating material may be used.

[0189] In addition, an opening is provided in the insulating layer 282, the insulating layer 284, and the insulating layer 286. Through the opening, the drain electrode 278b of the transistor 240, the electrode 102, and the electrode 10 3R, the electrode 103G, or the electrode 103B is electrically connected to the transistor 240. By driving the electrode 102, the electrode 103R, the electrode 103G, and the electrode 103B, The current or voltage that is applied to the transistor can be controlled. It is possible to provide an active matrix display device that controls the driving of the device 256. .

[0190] For other configurations of the light emitting device 256, refer to the configuration of the light emitting device 250. That's good.

[0191] <Components of the Light Emitting Device> Next, components of a light emitting device according to one embodiment of the present invention will be described in detail below.

[0192] <Hole injection layer> The hole injection layers 111 and 116 are formed by a pair of electrodes and a charge generation layer 115. It has the function of promoting hole injection by reducing the hole injection barrier, and is used, for example, as a transition metal oxide. It is formed by using transition metal oxides, phthalocyanine derivatives, or aromatic amines. Examples of the oxides include molybdenum oxide, vanadium oxide, ruthenium oxide, and tungsten oxide. Examples of phthalocyanine derivatives include, for example, For example, phthalocyanine (abbreviation: HPc) and copper phthalocyanine (abbreviation: CuPC) Examples of aromatic amines include benzidine derivatives and phenyl phthalocyanines. Diamine derivatives, etc. Polymerization of polythiophene and polyaniline, etc. Compounds such as poly(ethylene glycol), which is a self-doped polythiophene, can also be used. Dioxythiophene) / Poly(styrenesulfonic acid) (abbreviation: PEDOT / PSS), etc. Representative examples include polyvinylcarbazole and its derivatives, and side chain or main chain Polyarylenes having an aromatic amine skeleton or a π-electron-rich heteroaromatic skeleton and Derivatives, etc.

[0193] The hole injection layer is made of a hole transporting material (donor material) and a material that has electron accepting properties. Alternatively, a layer having a composite material of an electron-accepting material (acceptor material) can be used. A laminate of a layer containing a material exhibiting hole transfer properties and a layer containing a material having hole transport properties may be used. Charge can be exchanged between them in a steady state or in the presence of an electric field. The materials used were quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene. Examples of organic acceptors include 7,7,8,8-tetramethylphenylacetate derivatives. tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), Chloranil and 2,3,6,7,10,11-hexacyano-1,4,5,8,9,1 Electron-withdrawing groups (halogen groups or is a compound having a cyano group). Transition metal oxides, such as metals from Groups 4 to 8, Specifically, vanadium oxide, niobium oxide, titanium oxide, etc. Ta, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide Among them, molybdenum oxide is stable in the air, has low hygroscopicity, and is easy to handle. This is preferable because it is

[0194] As the hole transporting material, a material having a higher hole transporting property than an electron transporting property can be used. ×10 -6 cm 2 It is preferable that the material has a hole mobility of 1 / Vs or more. Examples of the compound include aromatic amines, carbazole derivatives, aromatic hydrocarbons, and stilbene derivatives. The hole transporting material may be a polymer compound.

[0195] As examples of materials with high hole transport properties, aromatic amine compounds include N,N' -Di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDP PA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino ]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3-methylphenyl) Amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-di Amine (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylaminophenyl Examples include]-N-phenylamino]benzene (abbreviation: DPA3B).

[0196] Specific examples of carbazole derivatives include 3-[N-(4-diphenyl PCz DPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamine No]-9-phenylcarbazole (abbreviation: PCzDPA2), 3,6-bis[N-(4- Diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazol (abbreviation: PCzTPN2), 3-[N-(9-phenylcarbazol-3-yl)-N -phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-biphenyl S[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenyl PCzPCA2, 3-[N-(1-naphthyl)-N-(9-phenyl) (phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzP CN1) and the like.

[0197] Other examples of carbazole derivatives include 4,4'-di(N-carbazolyl) )biphenyl (abbreviation: CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl 9-[4-(10-phenyl-9-anthryl)phenyl]benzene (abbreviation: TCPB), 1,4-bis[4-(N-carbazolyl)]-9H-carbazole (abbreviation: CzPA), [1,3,4-triphenyl]-2,3,5,6-tetraphenylbenzene and the like can be used.

[0198] As the aromatic hydrocarbon, for example, 2-tert-butyl-9,10-di(2- naphthyl)anthracene (abbreviation: t-BuDNA), 2-tert-butyl-9,10- Di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene DPPA, 2-tert-butyl-9,10-bis(4-phenylphenyl) 9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDBA), Helical (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2-tert-Butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4- Methyl-1-naphthyl)anthracene (abbreviation: DMNA), 2-tert-butyl-9, 10-Bis[2-(1-naphthyl)phenyl]anthracene, 9,10-bis[2-(1 -naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di( 1-naphthyl)anthracene, 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene 9,9'-bianthryl, 10,10'-diphenyl-9,9'- Bianthryl, 10,10'-bis(2-phenylphenyl)-9,9'-bianthryl , 10,10'-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9' -Bianthryl, anthracene, tetracene, rubrene, perylene, 2,5,8,11- Tetra(tert-butyl)perylene, etc. In addition, pentacene, coro Years and years can also be used. In this way, 1×10 -6 cm 2 Hole mobility above / Vs It is more preferable to use an aromatic hydrocarbon having 14 to 42 carbon atoms.

[0199] The aromatic hydrocarbon may have a vinyl skeleton. Examples of aromatic hydrocarbons include 4,4'-bis(2,2-diphenylvinyl)biphenyl. (abbreviation: DPVBi), 9,10-bis[4-(2,2-diphenylvinyl)phenyl] anthracene (abbreviation: DPVPA), etc.

[0200] In addition, for example, poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyl triphenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenyl Phenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylate amide] (abbreviation: PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N ,N'-Bis(phenyl)benzidine (abbreviation: Poly-TPD) and other polymer compounds. It can also be used.

[0201] As a material with high hole transport properties, for example, 4,4'-bis[N-(1-naphthyl )-N-phenylamino]biphenyl (abbreviation: NPB or α-NPD), N,N'-biphenyl S(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4 '-Diamine (abbreviation: TPD), 4,4',4''-tris(carbazol-9-yl) Triphenylamine (abbreviation: TCTA), 4,4',4''-tris[N-(1-naphthalene 1'-TNATA, 4,4'-N-phenylamino]triphenylamine ,4''-Tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA ), 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: B PAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenyl 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 (abbreviation: DFLADFL), N-(9,9-dimethyl-2-diphenylamino-9H-fluorenyl) Fluoren-7-yl)diphenylamine (abbreviation: DPNF), 2-[N-(4-diphenyl N-phenylaminophenyl)spiro-9,9'-bifluorene (abbreviation: D PASF), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl) PCBA1BP, 4,4'-diphenyl-4''-(9-phenyl) (phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP ), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl) Triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-( 9-Phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNB) B) 4-phenyldiphenyl-(9-phenyl-9H-carbazol-3-yl)amine N,N'-bis(9-phenylcarbazol-3-yl)- N,N'-Diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N,N',N ''-Triphenyl-N,N',N''-tris(9-phenylcarbazol-3-yl) ) Benzene-1,3,5-triamine (abbreviation: PCA3B), N-(4-biphenyl)- N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-carba PCBiF, N-(1,1'-biphenyl-4-yl)- N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl 9,9-Dimethyl-N- Phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluor PCBAF, N-phenyl-N-[4-(9-phenyl- 9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluorene-2-amine PCBASF, 2-[N-(9-phenylcarbazol-3-yl)-N- Phenylamino]spiro-9,9'-bifluorene (abbreviation: PCASF), 2,7-bis [N-(4-diphenylaminophenyl)-N-phenylamino]-spiro-9,9'- Bifluorene (abbreviation: DPA2SF), N-[4-(9H-carbazol-9-yl)fluorene N,N'-phenyl]-N-(4-phenyl)phenylaniline (abbreviation: YGA1BP), Bis[4-(carbazol-9-yl)phenyl]-N,N'-diphenyl-9,9-di Aromatic amine compounds such as methylfluorene-2,7-diamine (abbreviation: YGA2F) Also, 3-[4-(1-naphthyl)-phenyl]-9-phenyl can be used. -9H-Carbazole (abbreviation: PCPN), 3-[4-(9-phenanthryl)-phenyl 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 Nylcarbazole (abbreviation: CzTP), 4-{3-[3-(9-phenyl-9H-fluoro mmDBFFLBi-I I), 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzofuran) (Abbreviation: DBF3P-II), 1,3,5-tri(dibenzothiophen-4-yl)-benzyl DBT3P-II, 2,8-diphenyl-4-[4-(9-phenyl- 9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-I II), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-fluor (abbreviation: DBTFLP-IV), 4-[3-(triphenylene -2-yl)phenyl]dibenzothiophene (abbreviation: mDBTPTp-II) and other amines compounds, carbazole compounds, thiophene compounds, furan compounds, fluorene compounds, The materials mentioned herein include phenylene compounds, phenanthrene compounds, etc. is mainly 1×10 -6 cm 2 A material that has a hole mobility of at least / Vs. Substances other than these may be used as long as they have a higher hole transporting property than the above.

[0202] <Hole transport layer> The hole transport layers 112 and 117 are layers containing a hole transport material. The materials exemplified as the material for the hole injection layer can be used. The hole injection layer has the function of transporting the holes injected into the HOMO (High The highest occupied molecular orbital It is preferable that the HOMO level is the same as or close to the HOMO level.

[0203] The hole transport material is 1×10 -6 cm 2 / Vs or higher hole mobility However, any other material that has a higher hole transporting property than that of an electron transporting property may be used. The hole transport layer may be a single layer or a layer made of the above-mentioned material. Two or more layers may be laminated.

[0204] ≪Electron injection layer≫ The electron injection layers 114 and 119 are formed by one of the pair of electrodes and the charge generation layer 115. It has the function of promoting electron injection by reducing the electron injection barrier. For example, Group 1 metals, Group metals, or their oxides, halides, carbonates, etc. can be used. A composite material of an electron transport material and a material that exhibits electron donating properties (donor properties) is used. The electron donating material may be a Group 1 metal, a Group 2 metal, or a combination thereof. Specifically, for example, lithium fluoride (LiF) , Cesium Fluoride (CsF), Calcium Fluoride (CaF2), and Lithium Oxide (L iO x ) and alkaline earth metals, or their compounds. It is also possible to use rare earth metal compounds such as erbium fluoride (ErF3). The electron injection layer may be made of an electride. For example, a material in which electrons are highly added to a mixed oxide of calcium and aluminum is etc.

[0205] In addition, the electron injection layer is formed by adding an organic material (acceptor material) and an electron donor (donor material). A composite material in which the electron donor is mixed may be used. Since electrons are generated in the material, it has excellent electron injection and electron transport properties. The material is preferably a material that is excellent in transporting the generated electrons (electron transport material). Specifically, electron transport materials such as metal complexes and heteroaromatic compounds are used. The electron donor may be any substance that exhibits electron donating properties to organic materials. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferred, for example, lithium. Examples of these include ruthenium, cesium, magnesium, calcium, erbium, and ytterbium. In addition, alkali metal oxides and alkaline earth metal oxides are preferred, for example, lithium Examples of the oxides include magnesium oxide, calcium oxide, and barium oxide. Lewis bases such as tetrathiafulvalene (abbreviation: T Organic materials such as TF can also be used.

[0206] As the electron transport material, a material having a higher electron transporting property than a hole transporting property can be used. ×10 -6 cm 2 It is preferable that the material has an electron mobility of 0.1 V or more. π-electron deficient heteroaromatic compounds such as aromatic aromatic compounds, and metal complexes can be used. Specifically, for example, quinoline ligands, benzoquinoline ligands, oxazole ligands or a metal complex having a thiazole ligand. derivatives, triazole derivatives, phenanthroline derivatives, pyridine derivatives, bipyridin Examples of such derivatives include aryl amine derivatives and pyrimidine derivatives.

[0207] 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-quinolinolato)(4-phenylphenolato)a Aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Metal complexes having a quinoline or benzoquinoline skeleton, such as Znq In addition, bis[2-(2-benzoxazolyl)phenolato]zinc(II) ( Abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolato]zinc(II)( Metal complexes with oxazole and thiazole ligands such as ZnBTZ (abbreviation: In addition to metal complexes, 2-(4-biphenylyl)-5-(4 -tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1, 3-Bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2 -yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxo sadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 3-( 4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2, 4-Triazole (abbreviation: TAZ), 2,2',2''-(1,3,5-benzenetriazole Tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3 -(Dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazo mDBTBIm-II, Bathophenanthroline (Bphen), Heterocyclic compounds such as socuproin (BCP), 2-[3-(dibenzothiophene -4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq- II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibene 2-[3'-(9H -carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline( Abbreviation: 2mCzBPDBq), 2-[4-(3,6-diphenyl-9H-carbazole- 9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2CzPDBq-III ), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoki Sarin (abbreviation: 7mDBTPDBq-II) and 6-[3-(dibenzothiophene- 4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-I I), 4,6-bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyridine 4,6mDBTP2Pm-II, 4,6-bis[3-(9H-carbazo Diazines such as 4,6mCzP2Pm Heterocyclic compounds with a skeleton, 2-{4-[3-(N-phenyl-9H-carbazole-3 -yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3, Heterocyclic compounds with a triazine skeleton, such as 5-triazine (abbreviation: PCCzPTzn) , 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviation: 3 5DCzPPy), 1,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation Heterocyclic compounds with pyridine skeletons such as 4,4'-bis(5-methylphenyl) Heteroaromatic compounds such as (2-benzoxazolyl)stilbene (abbreviation: BzOs) Also usable are poly(2,5-pyridinediyl) (abbreviation: PPy), poly Li[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5- poly[(9,9-dioctylfluorene-2,7-diyl)] (abbreviation: PF-Py), PF-BPy) Polymers such as the following can also be used. The substances mentioned here are mainly 1×10 -6 c m 2 / Vs or higher. Any substance other than those mentioned above may be used.

[0208] ≪Electron transport layer≫ The electron transport layers 113 and 118 receive electrons injected from the other of the pair of electrodes via the electron injection layer 119. The electron transporting material has the function of transporting the electrons to the light-emitting layer. Materials with high conductivity can be used, and the -6 cm 2 / Vs or higher electron mobility As the electron transporting material, for example, a nitrogen-containing heteroaromatic compound is preferable. π-electron deficient heteroaromatic and metal complexes such as those shown below can be used. The quinoline ligand, benzoxidine ligand, etc., which are mentioned as electron transporting materials that can be used in the electron injection layer, Examples of the metal complexes include those having a thiazole ligand, an oxazole ligand, or a thiazole ligand. In addition, oxadiazole derivatives, triazole derivatives, and phenanthroline derivatives , pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, etc. Any substance other than the above may be used for the electron transport layer as long as it has a higher electron transporting property than the above. In addition, the electron transport layer may be a single layer or a laminate of two or more layers made of the above-mentioned substances. Good too.

[0209] In addition, a layer for controlling the movement of electron carriers may be provided between the electron transport layer and the light emitting layer. This is achieved by adding a small amount of a substance with high electron trapping properties to a material with high electron transport properties as described above. A layer that adjusts the carrier balance by suppressing the movement of electron carriers. This type of structure prevents light from being emitted by electrons penetrating the light-emitting layer. This is highly effective in suppressing problems that arise (such as a decrease in element life).

[0210] Alternatively, an n-type compound semiconductor may be used, such as titanium oxide, zinc oxide, or silicon oxide. tin oxide, tungsten oxide, tantalum oxide, barium titanate, barium zirconate , zirconium oxide, hafnium oxide, aluminum oxide, yttrium oxide, disilicic acid Oxides such as zinc oxide, nitrides such as silicon nitride, cadmium sulfide, zinc selenide , and zinc sulfide, etc. can also be used.

[0211] <Light-emitting layer> Either the light-emitting layer 120 or the light-emitting layer 140 is selected from the group consisting of purple, blue, and blue-green. The present invention provides a light-emitting material having a function of exhibiting an emission spectrum peak in at least one wavelength region. The other is selected from the group consisting of green, yellow-green, yellow, yellow-orange, orange, and red. The present invention has a light-emitting material that exhibits a light emission spectrum peak in at least one wavelength region. Each light-emitting layer is configured to contain a host material in addition to the light-emitting material. As the material for the second insulating layer, a structure having one or both of an electron transporting material and a hole transporting material is preferable. stomach.

[0212] The light-emitting material used in the light-emitting layer is a material that has a function of converting singlet excitation energy into light emission. A luminescent material having the function of converting triplet excitation energy into luminescence. Examples of the light-emitting material that can be used include the following:

[0213] As a light-emitting material capable of converting singlet excitation energy into light emission, There is no particular limitation on the fluorescent compound, but Thracene derivatives, tetracene derivatives, chrysene derivatives, phenanthrene derivatives, pyrene derivatives Conductors, perylene derivatives, stilbene derivatives, acridone derivatives, coumarin derivatives, pheno Xanthazine derivatives, phenothiazine derivatives, etc. are preferred, and the following materials can be used, for example: can be done.

[0214] Specifically, 5,6-bis[4-(10-phenyl-9-anthryl)phenyl]-2 ,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl -9-anthryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2 BPy), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N '-Diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H- 4'-(10-phenyl-9-anthryl)-4'-(10-phenyl-9-anthryl)triphenylamine YGAPA, 4-(9H-carbazol-9-yl)-4'-(9,10- Diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9- Diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carba PCAPA, 4-(10-phenyl-9-anthryl)- 4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: P CBAPA), 4-[4-(10-phenyl-9-anthryl)phenyl]-4'-(9 -phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPB A), perylene, 2,5,8,11-tetra(tert-butyl)perylene (abbreviation: TB P), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluorene -9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N ,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-phenyl 1,6mMemF LPAPrn), N,N'-bis(dibenzofuran-2-yl)-N,N'-diphenyl Pyrene-1,6-diamine (abbreviation: 1,6FrAPrn), N,N'-bis(dibenzothiophene) 1,6-diphenylpyrene-2-yl)-N,N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6 ThAPrn), N,N''-(2-tert-butylanthracene-9,10-diyl Di-4,1-phenylene)bis[N,N',N'-triphenyl-1,4-phenylenedi amine] (abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl 2-(2-(anthryl)phenyl)-9H-carbazol-3-amine (abbreviation: 2PCA PPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N' ,N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), N,N ,N',N',N'',N'',N''',N'''-Octaphenyldibenzo[g,p ]Chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), Coumarin 30, N -(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazol N-(9,10-diphenyl-2-anthryl)amine (abbreviation: 2PCAPA), )-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA ), N,N,9-triphenylanthracene-9-amine (abbreviation: DPhAPhA), Marine 6, Coumarin 545T, N,N'-Diphenylquinacridone (abbreviation: DPQd), Rubrene, 5,12-bis(1,1'-biphenyl-4-yl)-6,11-diphenyl Tetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]ene DC}-6-methyl-4H-pyran-4-ylidene)propanedinitrile M1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H- Benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}pro Pandinitrile (abbreviation: DCM2), N,N,N',N'-tetrakis(4-methylphenyl) p-mPhTD, 7,14-diphenyl Ru-N,N,N',N'-tetrakis(4-methylphenyl)acenaphtho[1,2-a] Fluoranthene-3,10-diamine (abbreviation: p-mPhAFD), 2-{2-isopropanol Pyr-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1 H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-yl 2-{2-tert-butyl-6-[ 2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzyl 4H-pyran-4-ylidene)propane DCJTB, 2-(2,6-bis{2-[4-(dimethylamino )phenyl]ethenyl}-4H-pyran-4-ylidene)propanedinitrile (abbreviation: B isDCM), 2-{2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl 2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl )ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJ TM), 5,10,15,20-tetraphenylbisbenzo[5,6]indeno[1,2 ,3-cd:1',2',3'-lm]perylene, and the like.

[0215] In addition, light-emitting materials (phosphorescent compounds) that have the function of converting triplet excitation energy into light emission ) may be, for example, an iridium-, rhodium-, or platinum-based organometallic complex, or Examples of iridium complexes include metal complexes, particularly organic iridium complexes, such as iridium orthometal complexes. The orthometalated ligands are 4H-triazole and 1H-triazole. Riazole ligands, imidazole ligands, pyridine ligands, pyrimidine ligands, pyrazine The metal complexes include porphyrin ligands and isoquinoline ligands. Examples of suitable complexes include platinum complexes having an isotopically linked ligand.

[0216] Examples of substances having a blue or green emission peak include tris{2-[5-(2 -methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazo {3-yl-κN2]phenyl-κC}iridium(III) (abbreviation: Ir(mpp tz-dmp)3), tris(5-methyl-3,4-diphenyl-4H-1,2,4-tris( riazolate)iridium(III) (abbreviation: Ir(Mptz)3), tris[4-(3- Biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato]i Iridium(III) (abbreviation: Ir(iPrptz-3b)3), tris[3-(5-biphenyl] (phenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazolato]irid Ir(III) (abbreviation: Ir(iPr5btz)3) Organometallic iridium complexes, tris[3-methyl-1-(2-methylphenyl)-5 -phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: Ir(M ptz1-mp)3), tris(1-methyl-5-phenyl-3-propyl-1H-1, 2,4-Triazolate)iridium(III) (abbreviation: Ir(Prptz1-Me)3) Organometallic iridium complexes with 1H-triazole skeletons such as fac-tris[1 -(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridium Ir(iPrpmi)3, tris[3-(2,6-dimethylphenyl] Nyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: Ir(dmpimpt-Me)3) Iridium complex, bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2 ’ ]iridium(III) tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), Bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ]iridium( III) Picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl) (fluoromethyl)phenyl]pyridinato-N,C 2’}Iridium(III) picolinate (abbreviation: Ir(CF3ppy)2(pic)), bis[2-(4',6'-difluorophenyl Phenyl)pyridinato-N,C 2’ ]Iridium(III) acetylacetonate (abbreviation: The ligand is a phenylpyridine derivative having an electron-withdrawing group such as Fir(acac) Among the above, the organometallic iridium complexes having a 4H-triazole skeleton are The organometallic iridium complexes are particularly preferred because of their excellent reliability and luminous efficiency.

[0217] In addition, examples of substances having a green or yellow emission peak include tris(4-methylphenyl) Ir(mppm)3, Tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: I r(tBuppm)3), (acetylacetonato)bis(6-methyl-4-phenylpyridine Iridium(III) (abbreviation: Ir(mppm)2(acac)), (acetylacetonate ruacetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium( III) (abbreviation: Ir(tBuppm)2(acac)), (acetylacetonato)bis [4-(2-norbornyl)-6-phenylpyrimidinato]iridium(III) (abbreviation Ir(nbppm)2(acac)), (acetylacetonato)bis[5-methyl-6 -(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: Ir(mpmppm)2(acac)), (acetylacetonato)bis{4,6-dimethyl 2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN3]phenyl- {κC}iridium(III) (abbreviation: Ir(dmppm-dmp)2(acac)), ( Acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III)( Abbreviation: Ir(dppm)2(acac) Dium complex, (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazinate) ) Iridium(III) (abbreviation: Ir(mppr-Me)2(acac)), (acetyl Acetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinate)iridium Pyrazine skeleton such as Ir(III) (abbreviation: Ir(mppr-iPr)2(acac)) An organometallic iridium complex, tris(2-phenylpyridinato-N,C 2’ ) Ili Ir(ppy)3, bis(2-phenylpyridinato-N,C 2’) Iridium(III) acetylacetonate (abbreviation: Ir(ppy)2(acac )), bis(benzo[h]quinolinato)iridium(III) acetylacetonate (abbreviation Name: Ir(bzq)2(acac)), tris(benzo[h]quinolinato)iridium ( III) (abbreviation: Ir(bzq)3), tris(2-phenylquinolinato-N,C 2’ ) Iridium(III) (abbreviation: Ir(pq)3), bis(2-phenylquinolinato-N, C 2’ ) Iridium(III) acetylacetonate (abbreviation: Ir(pq)2(acac Organometallic iridium complexes having a pyridine skeleton, such as bis(2,4-diphenyl -1,3-Oxazolato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation Name: Ir(dpo)2(acac)), bis{2-[4'-(perfluorophenyl)fluorene Phenyl]pyridinato-N,C 2’}Iridium(III) acetylacetonate (abbreviation: Ir(p-PF-ph)2(acac)), bis(2-phenylbenzothiazolato-N, C 2’ ) Iridium(III) acetylacetonate (abbreviation: Ir(bt)2(acac In addition to organometallic iridium complexes such as tris(acetylacetonato)(monophenanthate), Rare earth elements such as terbium(III) (abbreviation: Tb(acac)3(Phen)) Among the above, organometallic iridium complexes having a pyrimidine skeleton are The complexes are particularly preferred because they are remarkably excellent in reliability and luminous efficiency.

[0218] Examples of substances having 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 (5mdppm)2(dpm)), bis[4,6-di(naphthalene-1-yl)pyrimidinyl] Nato](dipivaloylmethanato)iridium(III) (abbreviation: Ir(d1npm)2( Organometallic iridium complexes with pyrimidine skeletons such as (acetylacetonamide) Nato)bis(2,3,5-triphenylpyrazinate)iridium(III) (abbreviation: Ir (tppr)2(acac)), bis(2,3,5-triphenylpyrazine)(dipiva Iridium(III) (abbreviation: Ir(tppr)2(dpm)), (A Cetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]yl Pyrazine skeleton such as Ir(III) (abbreviation: [Ir(Fdpq)2(acac)]) An organometallic iridium complex, tris(1-phenylisoquinolinato-N,C 2’ ) Iridium(III) (abbreviation: Ir(piq)3), bis(1-phenylisoquinolinato -N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: Ir(piq)2( In addition to organometallic iridium complexes with pyridine skeletons such as acac), 2,3,7, 8,12,13,17,18-Octaethyl-21H,23H-porphyrin platinum(II) ) (abbreviation: PtOEP), tris(1,3-diphenyl-1,3-propanediol), Pandionato)(monophenanthroline)europium(III) (abbreviation: Eu(DBM )3(Phen)), tris[1-(2-thenoyl)-3,3,3-trifluoroacetonitrile Nato](monophenanthroline)europium(III) (abbreviation: Eu(TTA)3(P Among the above, rare earth metal complexes having a pyrimidine skeleton are The organometallic iridium complexes are particularly preferred because of their outstanding reliability and luminous efficiency. In addition, organometallic iridium complexes with a pyrazine skeleton emit red light with good chromaticity. can be.

[0219] The material that can be used as the host material of the light-emitting layer is not particularly limited. For example, For example, tris(8-quinolinolato)aluminum(III) (abbreviation: Alq), tris(4 -Methyl-8-quinolinolato)aluminum(III) (abbreviation: Almq3), bis(1 0-Hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq2), Bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) ) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis [2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), Zinc(II) (abbreviation: ZnBTZ) Metal complexes of 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1, 3,4-Oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert-butyl 1,3,4-oxadiazol-2-yl)benzene (abbreviation: OXD-7 ), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl) -1,2,4-triazole (abbreviation: TAZ), 2,2',2''-(1,3,5-benzo Zentriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI) , Bathophenanthroline (abbreviation: Bphen), Bathocuproine (abbreviation: BCP), 9 -[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H -Heterocyclic compounds such as carbazole (abbreviation: CO11), NPB, TPD, BSPB, etc. In addition, aromatic amine compounds such as anthracene derivatives and phenanthrene derivatives can be used. , pyrene derivatives, chrysene derivatives, dibenzo[g,p]chrysene derivatives, and other condensed polycyclic aromatic Specifically, 9,10-diphenylanthracene (abbreviation: DPAn th), N,N-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl ]-9H-Carbazole-3-amine (abbreviation: CzA1PA), 4-(10-phenyl- 9-Anthryl)triphenylamine (abbreviation: DPhPA), YGAPA, PCAPA, N,9-diphenyl-N-{4-[4-(10-phenyl-9-anthryl)phenyl] Phenyl}-9H-carbazol-3-amine (abbreviation: PCAPBA), 2PCAPA, 6,12-Dimethoxy-5,11-diphenylchrysene, DBC1, 9-[4-(10- Phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H -Carbazole (abbreviation: DPCzPA), 9-phenyl-3-[4-(10-phenyl- 9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA), 7-[4-( 10-Phenyl-9-anthryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgDBCzPA), 6-[3-(9,10-diphenyl-2-anthryl)phenyl] phenyl]-benzo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9- Phenyl-10-{4-(9-phenyl-9H-fluoren-9-yl)biphenyl-4 '-yl}anthracene (abbreviation: FLPPA), 9,10-bis(3,5-diphenyl 9,10-di(2-naphthyl)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'-bianthryl (abbreviation: BANT), 9,9'-( Stilbene-3,3'-diyl)diphenanthrene (abbreviation: DPNS), 9,9'-(stilbene 1,3,5-Triphenyl-4,4'-diyl)diphenanthrene (abbreviation: DPNS2) 1-Pyrenylbenzene (TPB3), 5,12-diphenyltetracene, 5 , 12-bis(biphenyl-2-yl)tetracene, etc. Among various materials, we selected those with energy gaps larger than the energy gap of the above luminescent materials. In addition, the light-emitting material may be a phosphorescent material. In the case of a substance that emits light, the host material is Select a substance with a triplet excited energy greater than the energy difference between the triplet excited state and the triplet excited state. Just do it.

[0220] In addition, when multiple materials are used as the host material of the light-emitting layer, exciplexes (exciplexes) Two compounds that form a complex (also called an exciplex or exciplex) In this case, various carrier transport materials are appropriately used. However, in order to efficiently form an exciplex, it is necessary to use an electron transporting material and a hole transporting material. It is particularly preferred to combine the materials.

[0221] This is because an exciplex is formed by combining an electron transport material and a hole transport material. When the host material is used, the mixing ratio of the electron transport material and the hole transport material is adjusted. This makes it easy to optimize the carrier balance between holes and electrons in the light-emitting layer. By optimizing the carrier balance of holes and electrons in the light-emitting layer, By suppressing the bias of the area where recombination occurs, As a result, the reliability of the light emitting device can be improved.

[0222] The electron transporting materials include π-electron deficient heteroaromatic compounds such as nitrogen-containing heteroaromatic compounds and Specifically, the electron injection layer or the electron transport layer may be formed of a metal complex. Among them, a pyridine skeleton, a diazine skeleton, and the like can be used. Heterocyclic compounds having a triazine skeleton and a triazine skeleton are preferred because of their excellent reliability. Heterocyclic compounds having a diazine (pyrimidine and pyrazine) skeleton and a triazine skeleton are The electron transport property is high, and this contributes to reducing the driving voltage.

[0223] As hole transport materials, π-electron-rich heteroaromatic compounds (e.g., carbazole derivatives and isopropyl alcohols) are used. In particular, a hole transporting agent, such as an isopropyl alcohol, a phenyl alcohol derivative, an aromatic amine, or the like can be preferably used. Any hole transporting material that can be used in the injection layer or hole transport layer can be used. However, compounds with aromatic amine skeletons and compounds with carbazole skeletons are reliable. In addition, the hole transporting property is high, and this contributes to reducing the driving voltage, which is preferable.

[0224] The combination of the host material that forms the exciplex is not limited to the above-mentioned compounds. It is a combination that can transport carriers without being disturbed and can form an exciplex. The emission of the exciplex occurs in the longest wavelength absorption band in the absorption spectrum of the luminescent material (luminescent material (absorption corresponding to the transition from the singlet ground state to the singlet excited state of Other materials may also be used.

[0225] In addition, in order for the hole transport material and the electron transport material to efficiently form an exciplex, is a hole transporting material whose HOMO level is higher than that of the electron transporting material. LUMO (Lowest Unoccupied Molecular Orb) of Polymeric Materials It is preferable that the lowest unoccupied molecular orbital (LUMO) level of the electron transport material is higher than the LUMO level of the electron transport material. Specifically, the HOMO level of the hole transporting material and the HOMO level of the electron transporting material are preferably The energy difference is preferably 0.05 eV or more, more preferably 0.1 eV or more. and more preferably 0.2 eV or more. The energy difference between the LUMO level of the electron transporting material and the LUMO level of the electron transporting material is preferably 0.05 eV or more. It is more preferably 0.1 eV or more, and further preferably 0.2 eV or more.

[0226] In addition, the light-emitting material or host material of the light-emitting layer may be a thermally activated delayed fluorescence (TDF). ly activated delayed fluorescence (TADF) body The thermally activated delayed fluorescent substance has a triplet excitation energy level and a singlet excitation energy level. The difference in energy between the triplet excited state and the singlet excited state is small, and reverse intersystem crossing can cause the triplet excited state to change to the singlet excited state. The material has the function of converting energy. The energy difference between the S1 level and the T1 level is preferably greater than 0 eV and less than 0.3 eV. V or less, more preferably greater than 0 eV and less than 0.2 eV, and even more preferably greater than 0 eV and less than 0.2 eV. The largest is less than 0.1 eV.

[0227] The thermally activated delayed phosphor may be composed of one type of material or may be composed of multiple materials. For example, the thermally activated delayed phosphor may be composed of one type of material. In this case, the following materials can be used:

[0228] First, fullerene and its derivatives, acridine derivatives such as proflavine, and eosin are listed. In addition, magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn ), platinum (Pt), indium (In), or palladium (Pd) Examples of the metal-containing porphyrin include protoporphyrin. Phosphorus-tin fluoride complex (SnF2(Proto IX)), mesoporphyrin-sulfur fluoride SnF2(Meso IX) and hematoporphyrin-tin fluoride complex (SnF 2 (Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (SnF2(Copro III-4Me)), Octaethylporphyrin-Fluoride tin complex (SnF2(OEP)), etioporphyrin-tin fluoride complex (SnF2(Et io I)), octaethylporphyrin-platinum chloride complex (PtCl2OEP), etc. can be done.

[0229] As an example of a thermally activated delayed fluorescent material made of a single material, 2-(biphenyl) -4,6-bis(12-phenylindolo[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: PCCzPTzn), 2 -[4-(10H-phenoxazin-10-yl)phenyl]-4,6-diphenyl-1 ,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5-phenyl-5,10 -Dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4- Riazole (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-9,9'-ant Heteroaromatic rings with π-electron excess and π-electron deficient aromatic rings such as α-helixene (abbreviation: ACRSA) Heterocyclic compounds having a toe-shaped heteroaromatic ring can also be used. Electron-transporting and hole-transporting properties due to the presence of π-electron-deficient heteroaromatic rings In addition, the π-electron rich heteroaromatic ring and the π-electron deficient heteroaromatic ring are directly bonded to each other, and thus the π-electron rich heteroaromatic ring is preferably bonded to each other. The compound synthesized exhibits the donor property of π-electron-rich heteroaromatic rings and the acceptor property of π-electron-deficient heteroaromatic rings. The difference between the singlet and triplet excited energy levels is small. Therefore, it is particularly preferable.

[0230] In addition, when a thermally activated delayed fluorescent substance is used as a host material, two types of exciplexes are formed. In this case, it is preferable to use a combination of the above materials that form the above-mentioned exciplexes. It is particularly preferable to use a combination of an electron transporting material and a hole transporting material.

[0231] In addition, in one or both of the light-emitting layers 120 and 140, a host material and an emitting layer It may contain materials other than optical materials.

[0232] The light-emitting layer, the hole injection layer, the hole transport layer, the electron transport layer, the electron injection layer, and the electron The charge generation layer is formed by deposition (including vacuum deposition), inkjet, coating, and nozzle. The light-emitting layer can be formed by a method such as a photoprinting method or a gravure printing method. In addition to the above-mentioned materials, the hole injection layer, the hole transport layer, the electron transport layer, and the electron injection layer may be made of quantum dots. Inorganic compounds such as dots or polymeric compounds (oligomers, dendrimers, polymers, etc.) may also be used.

[0233] Quantum dots can also be used as light-emitting materials. Quantum dots are semiconductors with a size of a few nm. The nanocrystals are 1×10 3 1×10 6 It is composed of about atoms. Since the dots have a size-dependent energy shift, quantum dots made of the same material Even if the quantum dot is used, the emission wavelength varies depending on the size. This makes it possible to easily adjust the emission wavelength.

[0234] In addition, quantum dots have a narrow emission spectrum peak width, making it possible to obtain light emission with good color purity. Furthermore, the theoretical internal quantum efficiency of quantum dots is said to be nearly 100%. This is much higher than the 25% of organic compounds that emit fluorescent light, and the percentage of organic compounds that emit phosphorescence is 100%. This means that quantum dots can be used as light-emitting materials. In addition, quantum dots, which are inorganic compounds, can be used to obtain a light-emitting device with high luminous efficiency. Since the organic compound has excellent inherent stability, it is possible to obtain a light-emitting device having a long service life. This can be done.

[0235] The materials that make up quantum dots are elements in group 14 of the periodic table, elements in group 15 of the periodic table, Group 16 elements, compounds consisting of multiple Group 14 elements, elements belonging to Groups 4 to 14 Compounds of Group 16 elements and Group 2 elements, compounds of Group 16 elements and Group 2 elements, compounds of Group 13 elements Compounds of Group 15 elements and Group 13 elements and Group 17 elements, compounds of Group 14 elements and Compounds with group 15 elements, compounds with group 11 and group 17 elements, iron oxides, titanium oxide Examples of suitable semiconductor clusters include quartz crystals, chalcogenide spinels, and various semiconductor clusters.

[0236] Specifically, cadmium selenide (CdSe), cadmium sulfide (CdS), and cadmium telluride (CdS) Cadmium (CdTe), zinc selenide (ZnSe), zinc oxide (ZnO), zinc sulfide ( ZnS), zinc telluride (ZnTe), mercury sulfide (HgS), mercury selenide (HgSe) , mercury telluride (HgTe), indium arsenide (InAs), indium phosphide (InP ), Gallium arsenide (GaAs), Gallium phosphide (GaP), Indium nitride (InN) , gallium nitride (GaN), indium antimonide (InSb), gallium antimonide GaSb, Aluminum Phosphide (AlP), Aluminum Arsenide (AlAs), Aluminum selenium (AlSb), lead(II) selenide (PbSe), lead(II) telluride (I I) (PbTe), lead(II) sulfide (PbS), indium selenide (In2Se3), Indium telluride (In2Te3), indium sulfide (In2S3), gallium selenide Arsenic(III) sulfide (As2S3), arsenic(III) selenide (A s2Se3), arsenic(III) telluride (As2Te3), antimony(III) sulfide ( Sb2S3), antimony(III) selenide (Sb2Se3), antimony telluride ( III) (Sb2Te3), bismuth sulfide (III) (Bi2S3), bismuth selenide (III) (Bi2Se3), bismuth(III) telluride (Bi2Te3), silicon ( Si), silicon carbide (SiC), germanium (Ge), tin (Sn), selenium (Se), Tellurium (Te), Boron (B), Carbon (C), Phosphorus (P), Boron Nitride (BN), Phosphide Boron (BP), boron arsenide (BAs), aluminum nitride (AlN), aluminum sulfide Al2S3, barium sulfide (BaS), barium selenide (BaSe), telluride Barium (BaTe), calcium sulfide (CaS), calcium selenide (CaSe), Calcium telluride (CaTe), beryllium sulfide (BeS), beryllium selenide (B eSe), beryllium telluride (BeTe), magnesium sulfide (MgS), magnesium selenide (MgS) Magnesium (MgSe), Germanium sulfide (GeS), Germanium selenide (GeS e), germanium telluride (GeTe), tin(IV) sulfide (SnS2), tin(II) sulfide )(SnS), tin(II) selenide (SnSe), tin(II) telluride (SnTe), acid Lead(II) chloride (PbO), copper(I) fluoride (CuF), copper(I) chloride (CuCl), copper(I) bromide Copper(I) (CuBr), copper(I) iodide (CuI), copper(I) oxide (CuO), selenium Copper(I) oxide (CuSe), nickel(II) oxide (NiO), cobalt(II) oxide ( CoO), cobalt(II) sulfide (CoS), triiron tetroxide (Fe3O4), iron sulfide (II ) (FeS), manganese(II) oxide (MnO), molybdenum(IV) sulfide (MoS2) , vanadium(II) oxide (VO), vanadium(IV) oxide (VO2), tungsten oxide Tantalum(IV)(WO2), Tantalum(V)Oxide(Ta2O5), Titanium(TiO2, Ti2O5, Ti2O3, Ti5O9, etc.), zirconium oxide (ZrO2), silicon nitride Silicon (Si3N4), Germanium nitride (Ge3N4), Aluminum oxide (Al2O3) , barium titanate (BaTiO3), selenium, zinc and cadmium compound (CdZnS e), compounds of indium, arsenic and phosphorus (InAsP), compounds of cadmium, selenium and sulfur Compound of cadmium, selenium and tellurium (CdSeS), compound of cadmium, selenium and tellurium (CdSeTe), compound of zinc and Compounds of dopamine and selenium (ZnCdSe), compounds of indium, gallium and arsenic (I nGaAs), Indium Gallium Selenium Compound (InGaSe), Indium and Selenium and sulfur compounds (InSeS), copper, indium and sulfur compounds (e.g. CuIn S2) and combinations thereof, but are not limited thereto. Alternatively, so-called alloy-type quantum dots, whose compositions are expressed in any ratio, may be used. For example, dS x Se 1-x (x is any number between 0 and 1) alloy quantum dots are By changing the wavelength of light emitted, it is possible to change the wavelength of light emitted, making this an effective method for obtaining blue light. It is one of the.

[0237] Quantum dot structures include core type, core-shell type, and core-multishell type. Either of these can be used, but it is also advisable to cover the core with another inorganic material with a wider band gap. By forming a shell of material, defects and dangling bonds on the nanocrystal surface can be eliminated. This can reduce the effect of the photon emission. It is preferable to use core-shell or core-multishell quantum dots. Examples of materials include zinc sulfide (ZnS) and zinc oxide (ZnO).

[0238] In addition, quantum dots have a high proportion of surface atoms, making them highly reactive and less prone to aggregation. Therefore, a protective agent or a protective group is attached to the surface of the quantum dots. It is preferable that the protecting agent is attached or the protecting group is provided. It is possible to prevent aggregation and increase solubility in solvents. It is also possible to reduce reactivity and electrically It is also possible to improve stability. Examples of the protecting agent (or protecting group) include poliovirus. Polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene Polyoxyethylene alkyl ethers such as ethylene oleyl ether, tripropyl phosphatase phosphine, tributylphosphine, trihexylphosphine, trioctylphosphine, etc. Trialkylphosphines, polyoxyethylene n-octylphenyl ether, polyoxyethylene Polyoxyethylene alkylphenyl ethers such as oxyethylene n-nonylphenyl ether amine, tri(n-hexyl)amine, tri(n-octyl)amine, tri(n-decyl)amine ) tertiary amines such as amine, tripropylphosphine oxide, tributylphosphine Oxide, trihexylphosphine oxide, trioctylphosphine oxide, tridecylphosphine oxide Organic phosphorus compounds such as silylphosphine oxide, polyethylene glycol dilaurate, Polyethylene glycol diesters such as polyethylene glycol distearate, organic nitrogen compounds, such as nitrogen-containing aromatic compounds, such as lysine, lutidine, collidine, and quinolines; Hexylamine, octylamine, decylamine, dodecylamine, tetradecylamine , hexadecylamine, octadecylamine and other aminoalkanes, dibutyl sulfide Dialkyl sulfides such as dimethyl sulfoxide and dibutyl sulfoxide Organic sulfur compounds such as alkyl sulfoxides, sulfur-containing aromatic compounds such as thiophene, palmitate, etc. Higher fatty acids such as carboxylic acid, stearic acid, and oleic acid, alcohols, sorbitan fatty acid esters, Polyesters, fatty acid modified polyesters, tertiary amine modified polyurethanes, polyethyleneimine Examples include fluorinated substances.

[0239] The quantum dot may be a rod-shaped quantum rod. The quantum rod is polarized in the c-axis direction. By using quantum rods as light-emitting materials, it is possible to obtain light with a high degree of directivity. As a result, a light emitting device with good external quantum efficiency can be obtained.

[0240] When quantum dots are used as the light-emitting material of the light-emitting layer, the thickness of the light-emitting layer is 3 nm to 100 nm. m, preferably 10 nm to 100 nm, and the content of quantum dots in the light-emitting layer is 1 to 1 00% by volume. However, it is preferable to form the light-emitting layer only from quantum dots. In the case where the quantum dots are dispersed in a host as a light-emitting material to form a light-emitting layer, the host material The quantum dots are dispersed in a suitable liquid medium, or the host material and the quantum dots are dissolved or mixed in a suitable liquid medium. Disperse and apply wet processes (spin coating, casting, die coating, blade coating, etc.) Coating method, roll coating method, inkjet method, printing method, spray coating method, curtain coating The formation of the thin film may be achieved by a method such as a lattice method or a Langmuir-Blodgett method.

[0241] Examples of liquid media used in wet processes include methyl ethyl ketone, cyclohexane, etc. Ketones such as xanone, fatty acid esters such as ethyl acetate, halogens such as dichlorobenzene Hydrocarbons, aromatics such as toluene, xylene, mesitylene, and cyclohexylbenzene Hydrocarbons, aliphatic hydrocarbons such as cyclohexane, decalin, and dodecane, dimethylformamide, etc. Organic solvents such as dichloromethane (DMF) and dimethyl sulfoxide (DMSO) can be used. Cut.

[0242] Examples of polymer compounds that can be used in the light-emitting layer include poly[2-methoxy-5 -(2-ethylhexyloxy)-1,4-phenylenevinylene] (abbreviation: MEH-PP V), polyphenylene vinylene such as poly(2,5-dioctyl-1,4-phenylene vinylene), Poly(9,9-di-n-octylfluorenyl-2,7-diyl) Poly[(9,9-di-n-octylfluorenyl-2,7-diyl) (Abbreviation: F 8BT), poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt -(2,2'-bithiophene-5,5'-diyl)] (abbreviated as F8T2), poly[(9,9 -Dioctyl-2,7-divinylenefluorenylene)-alt-(9,10-anthracene Poly[(9,9-dihexylfluorene-2,7-diyl)-alt-(2,5 polyfluorene derivatives such as poly(3-hexylphenylene) Polyalkylthiophenes (PAT) such as polyalkylthiophene (P3HT) In addition, the polymer compounds and poly( 9-vinylcarbazole) (abbreviation: PVK), poly(2-vinylnaphthalene), poly[ (4-phenyl)(2,4,6-trimethylphenyl)amine (abbreviation: PTAA), etc. The polymer compound may be doped with a light-emitting low-molecular compound and used in the light-emitting layer. As the low molecular weight compound, the light emitting materials listed above can be used.

[0243] <Charge generation layer> The charge generating layer 115 is formed by adding an acceptor material, which is an electron acceptor, to a hole transporting material. Even if the structure is such that the electron transport material is a material having a donor property, the structure may be such that the donor property is added to the electron transport material. In addition, both of these configurations may be laminated.

[0244] When the charge generating layer 115 contains a composite material of an organic compound and an acceptor substance, The composite material may be any composite material that can be used for the hole injection layer. Examples include aromatic amine compounds, carbazole compounds, aromatic hydrocarbons, and polymer compounds ( Various compounds such as oligomers, dendrimers, polymers, etc. can be used. As an organic compound, the hole mobility is 1×10 -6 cm 2 / Vs or more However, if a material has a higher hole transporting property than an electron transporting property, this can be used. The composite material of the organic compound and the acceptor material may be a carrier. It has excellent injection and carrier transport properties, making it possible to achieve low-voltage and low-current operation. Cut.

[0245] The charge generating layer 115 may be a layer including a composite material of an organic compound and an acceptor substance. For example, the organic EL element may be formed as a laminated structure in which layers made of the organic material are combined. A layer including a composite material of a compound and an acceptor substance, and a layer including a donor substance selected from the group consisting of a compound and an acceptor substance. A layer containing a compound having a high electron transporting property and a layer containing a compound having a high electron transporting property may be formed in combination. A layer including a composite material of an organic compound and an acceptor substance is combined with a layer including a transparent conductive film. It may also be formed by combining the above.

[0246] From the viewpoint of light extraction efficiency, the charge generating layer 115 is required to be transparent to visible light (specifically, It is preferable that the charge generating layer 115 has a visible light transmittance of 40% or more. Furthermore, the charge generating layer 115 can function even if it has a lower conductivity than the pair of electrodes.

[0247] When the charge generating layer 115 is formed using the above-mentioned material, the light emitting layer is laminated. In this case, the increase in the driving voltage can be suppressed.

[0248] Electrode 101, electrode 102, and electrode 103 (electrode 103R, electrode 103G, and electrode 1 Electrode 101, electrode 102, and The electrodes 103 (electrodes 103R, 103G, and 103B) are made of a metal, an alloy, a conductive material, or the like. The conductive layer can be formed by using a conductive compound, a mixture or a laminate of these, etc. A typical example is aluminum (Al), and other metals include silver (Ag), tungsten, and chromium. Transition metals such as chromium, molybdenum, copper, and titanium, and arsenic such as lithium (Li) and cesium. Group 2 metals such as potassium metals, calcium, and magnesium (Mg) can be used. A rare earth metal such as ytterbium (Yb) may be used as the transition metal. As the material, an alloy containing the above metals can be used, for example, MgAg, AlLi, etc. Examples of the conductive compound include indium tin oxide (InTinO). Oxide (ITO), indium tin oxide (ITO) containing silicon or silicon oxide TSO), Indium Zinc Oxide, Tungsten Oxide Metal oxides such as indium oxide with tin and zinc oxide. As the reactive compound, an inorganic carbon-based material such as graphene may be used. The electrodes may be formed by laminating a plurality of these materials.

[0249] The light emitted from the light-emitting layer is extracted through one or both of the pair of electrodes. Therefore, at least the electrodes 102 and 103 (electrodes 103R, 103G, and The electrode 103B has a function of transmitting visible light. The material has a visible light transmittance of 40% or more and 100% or less, preferably 60% or more and 100% or less. and its resistivity is 1×10 -2 Conductive materials with a resistance of Ω cm or less are also included. In addition, the conductive film 10 of the electrode 103 (the electrode 103R, the electrode 103G, and the electrode 103B) 4 is made of a conductive material having a function of transmitting light and a function of reflecting light. The conductive material preferably has a visible light reflectance of 20% or more and 80% or less. is 40% or more and 70% or less, and its resistivity is 1×10 -2 Conductive material with Ω·cm or less When a material with low light transmittance such as a metal or an alloy is used for the conductive film 104, The thickness of the film is set to a level that allows visible light to pass through (for example, a thickness of 1 nm or more and 30 nm or less). That's good.

[0250] In this specification, the electrode 103 and the conductive film 106 each having a function of transmitting light are (The conductive film 106R, the conductive film 106G, and the conductive film 106B) have a function of transmitting visible light. Any material having the above properties and having electrical conductivity may be used. For example, the above-mentioned ITO is a typical example. In addition to the oxide conductor layer, an oxide semiconductor layer or an organic conductor layer containing an organic substance is included. The organic conductive layer containing an organic substance may be, for example, a layer containing an organic material (acceptor material) and an electron donor material. A layer including a composite material formed by mixing an organic material (donor material) and an electron receiving material. Examples of the layer include a layer containing a composite material formed by mixing a material with a receptacle (acceptor material). The resistivity of the transparent conductive film is preferably 1×10 5 Ω·cm or less, preferably 1× 10 4 Ω·cm or less.

[0251] In addition, the electrodes 101, 102, and 103 (electrodes 103R, 103G, and The electrode 103B) can be formed by sputtering, deposition, printing, coating, MBE (M Oligocular Beam Epitaxy, CVD, Pulsed Laser Deposition, The LD (Atomic Layer Deposition) method and the like can be used appropriately. do.

[0252] <Substrate> In addition, the light emitting device according to one aspect of the present invention is provided on a substrate made of glass, plastic, or the like. Regarding the order of fabrication on the substrate, the layers may be stacked in order from the electrode 101 side. They may be laminated in order from the pole 102 side.

[0253] The substrate on which the light-emitting device according to one embodiment of the present invention can be formed is, for example, glass or quartz. A flexible substrate may be used. The substrate is a flexible substrate, such as polycarbonate. Examples of the substrate include plastic substrates made of polyacrylate and polyarylate. In addition, a film made by vapor deposition may be used in the manufacturing process of a light-emitting device and an optical element. Any other material may be used as long as it functions as a support in the light-emitting device. Anything that can protect the mounting and optical elements can be used.

[0254] For example, in the present invention, a light emitting device can be formed using various substrates. The type of the substrate is not particularly limited. An example of the substrate is a semiconductor substrate (e.g., a single crystal substrate or silicon substrate), SOI substrate, glass substrate, quartz substrate, plastic substrate, metal Substrate, stainless steel substrate, substrate with stainless steel foil, tungsten substrate, substrate with tungsten foil, flexible substrate, laminated film, fibrous These include cellulose nanofibers (CNF), paper, and base films that contain these materials. Examples of glass substrates include barium borosilicate glass, aluminoborosilicate glass, and Soda lime glass, etc. Flexible substrates, laminated films, base films, etc. Examples of such materials include polyethylene terephthalate (PET), Polyethylene naphthalate (PEN), polyethersulfone (PES), polytetrafluoroethylene Examples of plastics include fluoroethylene (PTFE). Resins such as acrylic, etc., or polypropylene, polyester, etc. Examples include polyvinyl fluoride or polyvinyl chloride. Alternatively, an example is polyamide. , polyimide, aramid, epoxy, inorganic vapor deposition film, paper, etc. By manufacturing transistors using a conductor substrate, a single crystal substrate, or an SOI substrate, It has little variation in characteristics, size, or shape, high current capacity, and small size. It is possible to manufacture transistors. Circuits are constructed using such transistors. As a result, it is possible to reduce the power consumption of the circuit or to increase the degree of integration of the circuit.

[0255] In addition, a flexible substrate may be used as the substrate, and the light emitting device may be formed directly on the flexible substrate. Alternatively, a release layer may be provided between the substrate and the light emitting device. After the device is partially or completely completed, it can be separated from the substrate and used to transfer it to another substrate. In this case, the light emitting device can be transferred onto a substrate having poor heat resistance or a flexible substrate. The above-mentioned peeling layer may have a laminated structure of inorganic films, for example, a tungsten film and a silicon oxide film. Alternatively, a resin film such as polyimide may be formed on a substrate. do.

[0256] That is, a light emitting device is formed using one substrate, and then the light emitting device is transferred to another substrate, The light emitting device may be disposed on another substrate. In addition to the above mentioned substrates, cellophane substrates, stone substrates, wood substrates, fabric substrates (natural fibers (silk, cotton, Hemp), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate (including cellulose, cupra, rayon, recycled polyester, etc.), leather substrate, rubber substrate, etc. By using these substrates, light-emitting devices that are less likely to break and have high heat resistance can be manufactured. The light emitting device can be made thinner or light emitting device with a reduced weight.

[0257] Also, for example, a field effect transistor (FET) is formed on the above-mentioned substrate, and the FET and A light-emitting device may be fabricated on the electrically connected electrodes. This allows light emission by the FET. An active matrix type display device that controls the driving of an optical device can be manufactured.

[0258] <Method of manufacturing a light-emitting device> Next, a manufacturing method of a light-emitting device according to one embodiment of the present invention will be described below with reference to FIGS. Here, a method for manufacturing the light emitting device 250 shown in FIG.

[0259] 12 and 13 are cross-sectional views illustrating a method for manufacturing a light-emitting device according to one embodiment of the present invention. be.

[0260] The method for manufacturing the light emitting device 250 described below includes seven steps, from the first to the seventh steps. .

[0261] <First step> The first step is to remove some of the electrodes of the light-emitting device (specifically, electrodes 103R and 103G). , and the conductive film 108 and conductive film 104 constituting the electrode 103B are formed on the substrate 200. This is a process for performing the above-mentioned steps (see FIG. 12(A)).

[0262] In this embodiment, a transparent conductive film and a reflective conductive film are sequentially formed on a substrate 200. The conductive films 108 and 104 are formed by forming the conductive films 108 and 104 into desired shapes. The transparent conductive film is formed using, for example, ITSO, and the reflective conductive film is formed using, for example, For example, a silver-palladium-copper alloy film (Ag-Pd-Cu film, also called APC film) is used. In this way, the conductive film 108 and the conductive film 104 are processed and formed in the same process. This is preferable because it makes it possible to reduce the manufacturing cost.

[0263] Before the first step, a transistor may be formed on the substrate 200. The transistor and the conductive film 108 may be electrically connected to each other.

[0264] <<Second step>> In the second step, a conductive film constituting the electrode 102 and a conductive film constituting the electrode 103R are formed on the substrate 200. A conductive film 106R on the conductive film 104 forming the electrode 103G and a conductive film 106R on the conductive film 104 forming the electrode 103G are and the conductive film 106B on the conductive film 104 constituting the electrode 103B. In the first step, the conductive films 106R, 106G, and 106B are formed. By forming the conductive film 104 on the conductive film 104, the electrodes 103R, 103G, and 10 In this embodiment, the conductive film constituting the electrode 102, the conductive film 106 The ITSO film is used as the R, conductive film 106G, and conductive film 106B (see FIG. 12(B)). (see).

[0265] The conductive film constituting the electrode 102, the conductive film 106R, the conductive film 106G, and the conductive film 1 The method for forming 06B may be divided into several steps. Thus, the electrode 102 and the conductive film 10 are formed to a thickness that provides a suitable microcavity structure for each light-emitting element. 6R, conductive film 106G, and conductive film 106B can be formed.

[0266] The electrode 102 includes a conductive film 108, a conductive film 106R, a conductive film 106G, and a conductive film 106R. 06B may be formed simultaneously with one or more of the forming steps.

[0267] <Third step> The third step is to form partitions 145 that cover the ends of the electrodes of the light-emitting device ( See Figure 12(C).

[0268] The partition 145 has an opening so as to overlap with the electrode. In this embodiment, the partition wall 145 is made of a polyimide resin. Use fat.

[0269] In the first to third steps, the EL layer (layer containing an organic compound) may be damaged. Since there is no risk, various film formation methods and microfabrication techniques can be applied. In the method, a light-transmitting conductive film and a reflective conductive film are formed by sputtering, and then lithography is performed. The conductive film is patterned by a lithography method, and then wet-etched. The conductive film is processed into islands to form electrodes 102, 103R, 103G, and 10 Form 3B.

[0270] <Fourth step> The fourth step is to deposit the hole injection layer 111, the hole transport layer 112, the light emitting layer 120, the electron transport layer 122, and the electron transport layer 124. This is a step of forming a layer 113, an electron injection layer 114, and a charge generation layer 115 (FIG. 13(A) reference).

[0271] The hole injection layer 111 is formed by co-evaporating a hole transporting material and a material containing an acceptor. Co-evaporation is a process in which different materials are deposited on different surfaces. This is a deposition method in which two evaporation sources are simultaneously evaporated.

[0272] The hole injection layer 111 may be formed in a plurality of steps. By forming the layers separately, it is possible to obtain a film thickness that provides a suitable microcavity structure for each light-emitting element. A hole injection layer 111 may be formed.

[0273] The hole transport layer 112 can be formed by evaporating a hole transport material.

[0274] The light-emitting layer 120 is made of at least one material selected from the group consisting of purple, blue, and blue-green. It can be formed by evaporating a first light-emitting material that emits light in the wavelength range. A fluorescent organic compound can be used as the light-emitting material. The compound may be deposited alone or in combination with other materials. For example, fluorescent The organic compound is used as a guest material, and the host material has a higher excitation energy than the guest material. The guest material may be dispersed and deposited.

[0275] The electron transport layer 113 can be formed by evaporating a substance having a high electron transport property. The electron injection layer 114 can be formed by evaporating a material having a high electron injection property. It is possible.

[0276] The charge generating layer 115 is made of a material having a hole transporting property to which an electron acceptor is added. or a material in which an electron donor is added to an electron transporting material. It can be formed with.

[0277] <The fifth step> The fifth step is to deposit the hole injection layer 116, the hole transport layer 117, the light emitting layer 140, the electron transport layer 116, and the electron transport layer 117. 118, an electron injection layer 119, and an electrode 101 are formed (see FIG. 13(B)). .

[0278] The hole injection layer 116 is formed of the same material and in the same manner as the hole injection layer 111 described above. The hole transport layer 117 can be formed by the above-described hole transport layer 11. It can be formed from the same materials and in the same manner as 2.

[0279] The light-emitting layer 140 may be made of at least one material selected from the group consisting of green, yellow-green, yellow, orange, and red. The second luminescent material that emits light in at least one wavelength region can be deposited on the substrate. As the second light-emitting material, a phosphorescent organic compound can be used. The photoactive organic compound may be deposited alone or in combination with other materials. For example, a phosphorescent organic compound is used as a guest material, and a hole transporter with a larger excitation energy than the guest material is used. The guest material may be dispersed in a base material and then vapor-deposited. In this case, the two light-emitting layers may be light-emitting layers each having a different emission color. It is preferable to have an optical material.

[0280] The electron transport layer 118 can be formed by evaporating a substance having a high electron transport property. The electron injection layer 119 can be formed by evaporating a material having a high electron injection property. It is possible.

[0281] The electrode 101 can be formed of a conductive film having reflectivity. The layer 101 may have a single layer structure or a multilayer structure.

[0282] Through the above steps, on the electrodes 102, 103R, 103G, and 103B, The light emitting elements 222W, 222R, 222G, and 222 A light emitting device having B is formed on a substrate 200 .

[0283] <Sixth step> In the sixth step, the light-shielding layer 223, the optical element 224R, and the optical element 224 are formed on the substrate 220. G, and the optical element 224B are formed (see FIG. 13(C)).

[0284] The light-shielding layer 223 is a resin film containing a black pigment formed in a desired area. On the plate 220 and the light-shielding layer 223, an optical element 224R, an optical element 224G, and an optical element 224L are disposed. The optical element 224R is a resin film containing a red pigment applied to a desired area. In addition, the optical element 224G is formed by forming a resin film containing a green pigment in a desired area. In addition, the optical element 224B is formed by forming a resin film containing a blue pigment in a desired area. do.

[0285] <Seventh step> The seventh step is to separate the light emitting device formed on the substrate 200 and the light emitting device formed on the substrate 220. The light-shielding layer 223, the optical element 224R, the optical element 224G, and the optical element 224B are bonded together. This is the process of aligning the components and sealing them with a sealant (not shown).

[0286] Through the above steps, the light emitting device 250 shown in FIG. 8 can be formed.

[0287] Note that one embodiment of the present invention has been described in this embodiment. In the following, one embodiment of the present invention will be described. However, the embodiment of the present invention is not limited to these. That is, various inventive aspects are described in this and other embodiments. Therefore, one embodiment of the present invention is not limited to a specific embodiment. For example, one embodiment of the present invention Although an example in which the present invention is applied to a light-emitting device has been described, one embodiment of the present invention is not limited thereto. For example, in some cases or depending on the situation, one aspect of the present invention may be applied to a light emitting device. Alternatively, for example, in one embodiment of the present invention, the first light-emitting element may not have a light-emitting layer. The second light-emitting element has a first electrode and a second electrode, and the second light-emitting element has a light-emitting layer, the first electrode, and a third electrode. The second electrode is made of only the first conductive film, and the third electrode is made of the second conductive film and the first conductive film. The first electrode has a function of reflecting light, and the first conductive film and the third conductive film The first conductive film has a function of transmitting light, and the second conductive film has a function of reflecting light and a function of transmitting light. However, one embodiment of the present invention is not limited to this. Alternatively, depending on the situation, in one embodiment of the present invention, for example, the second light-emitting element may be a second conductive film. Alternatively, the first light emitting element may not have the second conductive film. Alternatively, the light emitting layer may be formed by coating.

[0288] The structure shown in this embodiment mode can be used in appropriate combination with other embodiment modes. Cut.

[0289] (Embodiment 2) In this embodiment, a light-emitting element that can be used in the light-emitting device shown in Embodiment 1 is The light emitting element and the light emitting mechanism of the light emitting element will be described below with reference to FIGS. In addition, in Figs. 14 to 16, the reference numerals denote parts having the same functions as those in Figs. 1 to 13. In addition, parts with similar functions may be designated with the same hatch pattern and the reference numerals may be omitted. The same reference numerals will be used to denote the same parts, and detailed descriptions thereof may be omitted.

[0290] <Configuration example 1 of light-emitting element> FIG. 14A is a schematic cross-sectional view of a light-emitting element 260. FIG.

[0291] The light-emitting element 260 shown in FIG. 14A has a pair of electrodes (electrodes 201 and 202) between them. In addition, a plurality of light-emitting units (light-emitting unit 208 and light-emitting unit 103 in FIG. 14A) One of the light-emitting units has an EL layer. It is preferable that the light-emitting element 260 has a similar structure to that of the light-emitting element 100. The following description will be given assuming that the electrode 201 functions as an anode and the electrode 202 functions as a cathode. The configuration of the electrode 202 may be reversed. The electrode 102 or electrode 103 (electrode 103R, electrode 103G, and electrode 103B) may be used. The electrode 201 may be configured as shown in the first embodiment. The above-mentioned configuration of the electrode 101 may be used.

[0292] In addition, in the light-emitting element 260 shown in FIG. 14(A), the light-emitting unit 208 and the light-emitting unit The light-emitting unit 208 and the light-emitting unit 210 are stacked, and a charge is provided between the light-emitting unit 208 and the light-emitting unit 210. The light-emitting unit 208 and the light-emitting unit 210 have the same structure. The configuration may be different.

[0293] The light emitting element 260 includes a light emitting layer 120 and a light emitting layer 140. In addition to the light-emitting layer 120, the knit 208 includes a hole injection layer 111, a hole transport layer 112, an electron transport The light-emitting unit 210 also includes a light-emitting layer 140. In addition to the above, a hole injection layer 116, a hole transport layer 117, an electron transport layer 118, and an electron injection layer 11 Has 9.

[0294] When the anode side surface of the light-emitting unit is in contact with the charge generating layer 115, the charge generating layer Since 115 can also play the role of a hole injection layer or a hole transport layer of the light-emitting unit, The light-emitting unit may have a structure in which a hole injection layer or a hole transport layer is not provided. When the cathode side surface of the light-emitting unit is in contact with the charge generating layer 115, the charge generating layer 11 Since 5 can also play the role of an electron injection layer or an electron transport layer of the light-emitting unit, The optical unit may have a structure in which the electron injection layer or the electron transport layer is not provided.

[0295] The charge generating layer 115 sandwiched between the light emitting unit 208 and the light emitting unit 210 is When a voltage is applied between the electrode 201 and the electrode 202, electrons are injected into one of the light-emitting units, It is sufficient if the hole is injected into the other light-emitting unit. For example, in FIG. When a voltage is applied so that the potential of electrode 202 is higher than the potential of electrode 201, The charge generating layer 115 injects electrons into the light emitting unit 208 and holes into the light emitting unit 210. Inject.

[0296] In addition, in FIG. 14(A), a light emitting element having two light emitting units is described. However, the same can be applied to a light-emitting element having three or more stacked light-emitting units. As shown in the light-emitting element 260, a plurality of light-emitting units are disposed between a pair of electrodes to generate electric charges. By separating the layers, it is possible to achieve high-brightness light emission while keeping the current density low. It is possible to realize a light emitting element having a long life and a low power consumption. do.

[0297] As shown in FIG. 14(B), the light-emitting layer 120 of the light-emitting unit 208 is The compound has a base material 121 and a guest material 122. The guest material 122 is a fluorescent compound. The light-emitting layer 140 of the light-emitting unit 210 is shown in FIG. As shown in FIG. 1, the compound has a host material 141 and a guest material 142. The light-emitting layer 141 includes an organic compound 141_1 and an organic compound 141_2. The guest material 142 contained in 140 is a phosphorescent compound, which will be described below.

[0298] <Light Emitting Mechanism of the Light Emitting Layer 120> The light emitting mechanism of the light emitting layer 120 will be described below.

[0299] The charge injected from the pair of electrodes (electrodes 201 and 202) or the charge generating layer 115 The electrons and holes recombine in the light-emitting layer 120 to generate excitons. Since there is a large amount of host material 121 compared to material 122, the generation of excitons results in An excited state of the host material 121 is formed.

[0300] An exciton is a pair of carriers (electrons and holes). Therefore, the material in which the excitons are generated is in an excited state.

[0301] When the excited state of the formed host material 121 is a singlet excited state, the host material 12 Singlet excitation energy is transferred from the S1 level of 1 to the S1 level of the guest material 122. As a result, the singlet excited state of the guest material 122 is formed.

[0302] Since the guest material 122 is a fluorescent compound, the guest material 122 is in a singlet excited state. When the state is formed, the guest material 122 rapidly emits light. In order to achieve this, it is preferable that the guest material 122 has a high fluorescence quantum yield. In the case of 122, carriers may recombine and the resulting excited state may be a singlet excited state. Same here.

[0303] Next, when the triplet excited state of the host material 121 is formed by carrier recombination, In this case, the energy levels of the host material 121 and the guest material 122 are The correlation between the positions is shown in FIG. 14(C). The notations and symbols in FIG. 14(C) are as follows: The T1 level of the host material 121 is lower than the T1 level of the guest material 122. In FIG. 14C, this case is illustrated. 1 level may be higher than the T1 level of the guest material 122.

[0304] Correlation between the energy levels of the host material 121 and the guest material 122 in the light-emitting layer 120 is shown in FIG. 14(C). The notations and symbols in FIG. 14(C) are as follows: . ·Host(121): Host material 121 Guest(122): Guest material 122 (fluorescent compound) ·S FH : S1 level of the host material 121 T FH : T1 level of the host material 121 ·S FG : S1 level of guest material 122 (fluorescent compound) T FG : T1 level of guest material 122 (fluorescent compound)

[0305] As shown in FIG. 14(C), triplet-triplet annihilation (TTA) Let Annihilation) is a triplet generated by carrier recombination. The two excitons interact with each other, transferring excitation energy and exchanging spin angular momentum. As a result, the S1 level (S FH ) energy A reaction occurs in which the excitons are converted into singlet excitons (see Figure 14(C) TTA). The singlet excitation energy of 21 is S FH From the lower energy guest material 1 22 S1 levels (S FG ) energy transfer occurs (see route E5 in Figure 14(C)), A singlet excited state is formed in the guest material 122, and the guest material 122 emits light.

[0306] In addition, when the density of triplet excitons in the light-emitting layer 120 is sufficiently high (for example, 1×10 12 cm -3 In the above, the deactivation of a single triplet exciton is ignored, and the deactivation of two adjacent triplet excitons is considered. Only the reaction by the child can be considered.

[0307] In addition, when carriers recombine in the guest material 122 to form a triplet excited state, However, the triplet excited state of the guest material 122 is thermally deactivated, making it difficult to utilize it for light emission. However, the T1 level (T FH ) is the T1 equivalent of guest material 122 Place(T FG ), the triplet excitation energy of guest material 122 is lower than that of guest material 1 22 T1 levels (T FG ) to the T1 level of the host material 121 (T FH ) Energy transfer (See route E6 in FIG. 14(C)) and then used for TTA.

[0308] That is, the host material 121 converts triplet excitation energy into singlet excitation energy by TTA. It is preferable that the light-emitting layer 120 has a function of converting the generated energy into the light-emitting layer 120. A portion of the triplet excitation energy is converted to singlet excitation energy by TTA in the host material 121. The singlet excitation energy is converted into singlet energy, and the singlet excitation energy is transferred to the guest material 122, thereby producing a fluorescent material. To achieve this, the S1 level (S FH ) is the S1 level (S FG ) is preferable. The T1 level (T FH ) is the T1 level (T FG ) lower It is preferable.

[0309] In particular, the T1 level (T FG ) is the T1 level of the host material 121 ( T FH ), the weight ratio of the host material 121 to the guest material 122 is In particular, the weight ratio of the guest material 122 is preferably low. The amount is preferably greater than 0 and less than or equal to 0.05 by weight relative to the host material 121. This can reduce the probability of carrier recombination in the guest material 122. In addition, the T1 level (T FH) to the T1 level (T FG ) This can reduce the probability of energy transfer to the

[0310] The host material 121 may be composed of a single compound or a plurality of compounds. It may be formed.

[0311] <Light Emitting Mechanism of the Light Emitting Layer 140> Next, the light emitting mechanism of the light emitting layer 140 will be described below.

[0312] The organic compound 141_1 and the organic compound 141_2 in the light-emitting layer 140 form an exciplex. It is preferable to form

[0313] The combination of organic compound 141_1 and organic compound 141_2 forms an exciplex with each other. Any combination that can form a hole transporting compound is acceptable. It is more preferable that the other is a compound having an electron transporting property.

[0314] The organic compound 141_1, the organic compound 141_2, and the guest material in the light-emitting layer 140 The correlation between the energy levels of 142 and 143 is shown in FIG. The notes and 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) TPH2 :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 exciplex T PE :T1 level of the exciplex

[0315] The organic compound 141_1 and the organic compound 141_2 form an exciplex, and the S 1 level (S PE ) and T1 level (T PE ) are adjacent energies (Figure 15(B ) See route E7).

[0316] Organic compound 141_1 and organic compound 141_2 are such that one accepts holes and the other accepts electrons. Alternatively, when one of the two is excited, it quickly forms an exciplex. Therefore, the exciplex in the light-emitting layer 140 Most of the excited molecules exist as exciplexes. The excited energy levels of the exciplexes (S PE Also is T PE ) is a host material (organic compound 141_1 and organic compound 141_2) that forms an exciplex. 41_2) S1 level (S PH1 and S PH2 ) and therefore has a lower excitation energy. This allows the host material 141 to be excited by the excitation light. The driving voltage of the element can be reduced.

[0317] And the (S PE ) and (T PE ) and the energy of the guest material 142 (phosphorescent compound) to the T1 level to obtain light emission (Figure 15(B) Route E8, See E9).

[0318] In addition, the T1 level of the exciplex (T PE ) is the T1 level (T PG )twist By doing so, the singlet excitation energy and and triplet excitation energy in the S1 level (S PE ) and T1 level (T PE )mosquito The T1 level (T PG ) energy can be transferred to

[0319] In order to efficiently transfer excitation energy from the exciplex to the guest material 142, , the T1 level of the exciplex (T PE ) are each organic compound that forms an exciplex (organic compound 14 1_1 and organic compound 141_2) T1 level (T PH1 and T PH2 ) or It is preferable that the organic compound 141_1 and the organic Compound 141_2) is less likely to quench the triplet excitation energy of the exciplex. Thus, energy transfer occurs efficiently from the exciplex to the guest material 142.

[0320] In addition, the organic compound 141_1 and the organic compound 141_2 efficiently form an exciplex. In order to achieve this, the HOMO level of one of the organic compounds 141_1 and 141_2 must be The HOMO level of one is higher than the LUMO level of the other, and the LUMO level of the other is higher than the LUMO level of the other. For example, the organic compound 141_1 has a hole transporting property, and the organic compound 141_2 has a hole transporting property. When the organic compound 141_1 has electron transport properties, the HOMO level of the organic compound 141_2 It is preferable that the LUMO level of the organic compound 141_1 is higher than the HOMO level of the organic compound 141_2. It is preferable that the LUMO level of the organic compound 141_2 is higher than that of the organic compound 141_3. When organic compound 141_1 has a hole transporting property and organic compound 141_2 has an electron transporting property, organic compound 1 It is preferable that the HOMO level of 41_2 is higher than the HOMO level of the organic compound 141_1. , the LUMO level of organic compound 141_2 is higher than the LUMO level of organic compound 141_1. Specifically, it is preferable that the HOMO level of the organic compound 141_1 and the HOMO level of the organic compound 141 The energy difference between the HOMO level of _2 is preferably 0.05 eV or more, and more preferably The electron transport potential is preferably 0.1 eV or more, and more preferably 0.2 eV or more. The energy difference between the LUMO level of organic compound 141_1 and the LUMO level of organic compound 141_2 is , preferably 0.05 eV or more, more preferably 0.1 eV or more, and even more preferably It is preferably 0.2 eV or more.

[0321] In addition, the combination of organic compound 141_1 and organic compound 141_2 has hole transport properties. In the case of a combination of a compound having a property of electron transport and a compound having a property of electron transport, the mixing ratio Specifically, the carrier balance can be easily controlled by using a hole transporting material. The weight ratio of the compound having an electron transporting property to the compound having an electron transporting property is preferably in the range of 1:9 to 9:1. In addition, by having this configuration, the carrier balance can be easily controlled. In addition, the carrier recombination region can be easily controlled.

[0322] <Energy transfer mechanism> Next, the control of the energy transfer process between the host material 141 and the guest material 142 molecules The mechanism of energy transfer between molecules is the Förster mechanism (bipolar Two mechanisms have been proposed: the electron-dipole interaction mechanism and the Dexter mechanism (electron exchange interaction). Here, energy transfer between the host material 141 and the guest material 142 is The process is similar when the host material 141 is an exciplex.

[0323] <Förster mechanism> In the Förster mechanism, the energy transfer does not require direct contact between the molecules, but occurs via the host Energy transfer occurs through the resonance phenomenon of dipole vibration between the material 141 and the guest material 142. The host material 141 transfers energy to the guest material 142 due to the resonance phenomenon of the dipole vibration. The excited host material 141 goes to the ground state, and the guest material 14 2 becomes excited. The rate constant of the Förster mechanism is k h*→g is shown in formula (1). .

[0324]

number

[0325] In formula (1), ν represents the frequency, and f' h (ν) is the standard value of the host material 141 The emission spectrum (fluorescence spectrum when discussing energy transfer from a singlet excited state) is calculated. spectrum when discussing energy transfer from triplet excited states), ε g (ν) represents the molar extinction coefficient of the guest material 142, N represents Avogadro's number, and n represents the refractive index of the medium, and R represents the intermolecular distance between the host material 141 and the guest material 142. where τ is the measured lifetime of the excited state (fluorescence lifetime or phosphorescence lifetime) and c is the speed of light. , φ is the emission quantum yield (or the fluorescence quantum yield when considering energy transfer from a singlet excited state) When discussing energy transfer from a triplet excited state, it is the phosphorescence quantum yield, and when discussing energy transfer from a triplet excited state, it is the phosphorescence quantum yield, and K 2 teeth , a coefficient (between 0 and 141) that represents the orientation of the transition dipole moment of the host material 141 and the guest material 142 In the case of random orientation, K 2 =2 / 3.

[0326] <Dexter System> In the Dexter mechanism, the host material 141 and the guest material 142 are bonded together with orbital overlap. The electrons of the host material 141 in the excited state and the guest material 14 in the ground state approach each other within the effective distance of each other. Energy transfer occurs through the exchange of electrons with 2. The rate constant for the Dexter mechanism is k h*→g is shown in formula (2).

[0327]

number

[0328] In formula (2), h is the Planck constant, and K is a constant with the dimension of energy. where ν is the frequency and f' is the h (ν) is the normalized emission spectrum of the host material 141. Spectra (fluorescence spectrum when discussing energy transfer from singlet excited states, triplet When discussing energy transfer from an excited state, it represents the phosphorescence spectrum, and ε' g (ν) is , represents the normalized absorption spectrum of the guest material 142, L represents the effective molecular radius, R represents the intermolecular distance between the host material 141 and the guest material 142 .

[0329] Here, the energy transfer efficiency φ from the host material 141 to the guest material 142 ET is a number It is expressed by equation (3). rThe emission process of the host material 141 (energy from the singlet excited state) When discussing energy transfer, we use the term fluorescence. When discussing energy transfer from triplet excited states, we use the term phosphorescence. light), and k n is the non-radiative process (thermal deactivation and intersystem crossing) of the host material 141. represents the rate constant, and τ represents the measured lifetime of the excited state of the host material 141.

[0330]

number

[0331] From equation (3), the energy transfer efficiency φ ET To increase the rate of energy transfer, Degree constant k h*→g By increasing the other competing rate constants k r +k n (=1 / τ) is relatively It turns out that the smaller it is, the better.

[0332] <Concept for improving energy transfer> In the case of energy transfer via the Förster mechanism, the energy transfer efficiency φ ET is the amount quantum yield φ (fluorescence quantum yield when considering energy transfer from singlet excited states, triplet When discussing energy transfer from the first excited state, the higher the phosphorescence quantum yield, the better. Emission spectrum of host material 141 (when discussing energy transfer from the singlet excited state) is the fluorescence spectrum) and the absorption spectrum of guest material 142 (from the singlet ground state to the triplet excitation It is preferable that the overlap with the absorption corresponding to the transition to the excited state is large. It is also preferable that the molar absorption coefficient of the material 142 is high. This means that the spectrum overlaps with the absorption band that appears on the longest wavelength side of the guest material 142.

[0333] In addition, in the energy transfer by the Dexter mechanism, the rate constant k h*→g Make it bigger In this study, the emission spectrum of the host material 141 (energy transfer from the singlet excited state) is discussed. If the energy transfer from the triplet excited state is discussed, the fluorescence spectrum is used. The absorption spectrum of the 142 guest material (from the singlet ground state to the triplet excited state) The greater the overlap with the absorption corresponding to the transition, the better. Therefore, the efficiency of energy transfer is The optimization is performed on the emission spectrum of the host material 141 and the longest wavelength side of the guest material 142. This is achieved by the overlap of the absorption bands of the

[0334] In addition, in the same manner as the energy transfer from the host material 141 to the guest material 142, an exciplex The energy transfer process from the nucleus to the guest material142 was also investigated using the Förster mechanism and the Deca- Energy transfer occurs via both mechanisms of the star mechanism.

[0335] That is, the host material 141 is capable of efficiently transferring energy to the guest material 142. The exciplex has a function as an energy donor, and the combination that forms the exciplex Organic Compound 141_1 and Organic Compound 141_2 are included. Organic Compound 141_1 The exciplex formed by organic compound 141_1 and organic compound 141_2 is Compound 141_2 can be formed with lower excitation energy than the excited state of the compound 141_2 alone. Therefore, the driving voltage of the light emitting element can be reduced.

[0336] Furthermore, the T of the guest material 142, which acts as an energy acceptor, was calculated from the S1 level of the exciplex. In order to facilitate the energy transfer to the 1st level, the emission spectrum of the exciplex and the It is preferable that the absorption band of the photoresist material 142 overlaps with the absorption band of the photoresist material 142 that appears on the longest wavelength side (lowest energy side). By doing so, it is possible to increase the efficiency of generating the triplet excited state of the guest material 142. do.

[0337] The exciplex generated in the light-emitting layer 140 has a singlet excited energy level and a triplet excited energy level. The emission spectrum of exciplexes is characterized by the close proximity of the excited energy levels. By overlapping the absorption bands of the 142 guest material and the 143 guest material, , the triplet excited energy level of the exciplex is converted to that of the guest material 142. This also makes it easier for energy transfer to occur to occur.

[0338] By configuring the light-emitting layer 140 as described above, the guest material 142 (phosphorescent It is therefore possible to efficiently obtain light emission from the luminescent compound.

[0339] In addition, the process of the above-mentioned routes E7 to E9 is referred to as ExTET (Ex It is sometimes called plex-triplet energy transfer. In other words, the light-emitting layer 140 is configured to transmit excitation energy from the exciplex to the guest material 142. In this case, the T PE From S PE High efficiency of reverse intersystem crossing is required Instead, S PE Since the quantum yield of light emitted from the It becomes possible.

[0340] In each of the above configurations, the guest used for the light emitting unit 208 and the light emitting unit 210 The light emitting colors of the light emitting materials may be the same or different. A guest material having a function of emitting light of the same color in the light emitting unit 208 and the light emitting unit 210. In this case, the light emitting element 260 becomes a light emitting element that exhibits high light emission luminance with a small current value, which is preferable. In addition, the light emitting unit 208 and the light emitting unit 210 emit light of different colors. When the light-emitting device 260 has a guest material having the function of emitting light of multiple colors, the light-emitting device 260 emits light of multiple colors. In this case, either or both of the light-emitting layer 120 and the light-emitting layer 140 are preferably By using a plurality of light-emitting materials having different emission wavelengths, the light emitted by the light-emitting element 260 The spectrum is a composite of light with different emission peaks, so there are at least two The emission spectrum has a maximum value of

[0341] The above-mentioned configuration is also suitable for obtaining white light emission. By making the colors complementary to each other, white light can be obtained. The guest is then mixed with the guest to produce a white emission, or at least an emission having red, green and blue light. It is preferable to select the material.

[0342] In addition, the light-emitting unit 208 and the light-emitting unit 210 have guest materials that emit light of different colors. In this case, the emission from the light-emitting layer 120 has a peak in the shorter wavelength side than the emission from the light-emitting layer 140. It is preferable to use a material having a high triplet excitation energy level. The light-emitting element used in this study tends to have a tendency to deteriorate in luminance quickly. By using TA, it is possible to provide a light-emitting element with little deterioration in luminance.

[0343] In addition, at least one of the light-emitting layer 120 and the light-emitting layer 140 is further divided into layers, Each of the divided layers may contain a different light-emitting material. Alternatively, at least one of the light-emitting layers 140 may be composed of two or more layers. For example, a first light-emitting layer and a second light-emitting layer are laminated in this order from the hole transport layer side to form a light-emitting layer. In this case, a material having a hole transporting property is used as the host material of the first light-emitting layer, and A structure in which a material having an electron transporting property is used as the host material. The light-emitting material in the first light-emitting layer and the light-emitting material in the second light-emitting layer may be the same or different. Even if the material has a function of emitting light of the same color, it may have a function of emitting light of different colors. A plurality of light-emitting materials each having a function of emitting light of a different color may be used. By using this configuration, it is possible to obtain white light with high color rendering properties consisting of the three primary colors or four or more colors. It is also possible.

[0344] <Light-emitting element configuration example 2> Next, regarding examples of configurations of the light-emitting element shown in FIG. 14 and FIG. 15, FIG. 16(A) and FIG. 16(B) will be described. The following explanation will be given using (C).

[0345] FIG. 16A is a schematic cross-sectional view of the light emitting element 262. FIG.

[0346] The light-emitting element 262 shown in FIG. 16A is a light-emitting element between a pair of electrodes (electrodes 201 and 202). In the light-emitting element 262, the electrode 202 is a positive electrode. The following description will be given assuming that the electrode 201 functions as an electrode and the electrode 202 functions as a cathode. The structure of the electrode 202 may be reversed. The electrode 102 or electrode 103 (electrode 103R, electrode 103G, and electrode 10 3B) may be used. The configuration of the electrode 101 may be used.

[0347] The EL layer 100 also includes a light-emitting layer 130, which is a light-emitting layer 120 and a light-emitting In the light-emitting element 262, the EL layer 100 includes a light-emitting layer and a A hole injection layer 111, a hole transport layer 112, an electron transport layer 118, and an electron injection layer 119 are formed on the substrate. Although shown in the figure, these laminated structures are only examples, and the EL layer 10 in the light-emitting element 262 The configuration of the EL layer 100 is not limited to these. For example, the stacking order of the above layers in the EL layer 100 is Alternatively, the EL layer 100 may be provided with a functional layer other than the above-mentioned layers. The functional layer may have, for example, a function of reducing the hole or electron injection barrier, a function of providing a hole or electron a function of improving the transportability of holes or electrons, a function of inhibiting the transportability of holes or electrons, The configuration may have a function of generating a signal.

[0348] As shown in FIG. 16B, the light-emitting layer 120 is made of a host material 121 and a guest material The light-emitting layer 140 includes a host material 141 and a guest material 142. The host material 141 includes an organic compound 141_1 and an organic compound 141_2. In addition, the guest material 122 is a fluorescent compound, and the guest material 142 is a phosphorescent compound. The following is an explanation.

[0349] <Light Emitting Mechanism of the Light Emitting Layer 130> The light-emitting mechanism of the light-emitting layer 120 is the same as that of the light-emitting layer 120 shown in FIG. 14(B)(C). The light-emitting mechanism of the light-emitting layer 140 is the light-emitting mechanism shown in FIGS. The light emission mechanism is the same as that of the layer 140.

[0350] As shown in FIG. 16(A), the light-emitting layer 120 and the light-emitting layer 140 are in contact with each other. In this case, the exciplex of the light-emitting layer 140 emits a light beam at the interface between the light-emitting layer 120 and the light-emitting layer 140. Energy transfer from the light-emitting layer 120 to the host material 121 (especially the energy of the triplet excited level) Even if the triplet excitation energy is converted into light emission in the light-emitting layer 120, the triplet excitation energy is converted into light emission in the light-emitting layer 120. It is possible.

[0351] The T1 level of the host material 121 in the light-emitting layer 120 is the same as that of the organic compound in the light-emitting layer 140. It is preferable that the T1 level of the light-emitting layer is lower than the T1 level of the organic compound 141_1 and the organic compound 141_2. In 120, the S1 level of the host material 121 is the S 1 level, and the T1 level of the host material 121 is higher than the T1 level of the guest material 122 (the fluorescent compound It is preferable that the T1 level is lower than that of the T1 level of the compound.

[0352] Specifically, when TTA is used for the light-emitting layer 120 and ExTET is used for the light-emitting layer 140, The correlation of the energy levels is shown in FIG. is as follows: ·Fluorescence EML(120): Emitting layer 120 (fluorescent emitting layer) Phosphorescence EML(140): Emitting layer 140 (phosphorescent emitting layer) ·Host(121): Host material 121 Guest(122): Guest material 122 (fluorescent compound) ·Host(141_1): Organic compound 141_1 (host material) Guest (142): Guest material 142 (phosphorescent compound) ·Exciplex: Excitonic complex (organic compound 141_1 and organic compound 141_2) ·S FH : S1 level of the host material 121 T FH : T1 level of the 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 the host material (organic compound 141_1) T PH : T1 level of the host material (organic compound 141_1) T PG :T1 level of guest material 142 (phosphorescent compound) ·S E : S1 level of the exciplex T E :T1 level of the exciplex

[0353] As shown in Figure 16(C), since exciplexes exist only in excited states, The exciton diffusion between the exciton complex and the excited complex is difficult. E , T E ) is an organic compound 141_1 of the light-emitting layer 140 (i.e., a host material of a phosphorescent compound). ) excited energy level (S PH , T PH ), so the exciplex is converted to the organic compound 1 There is no diffusion of energy to the phosphorescent light-emitting layer 41_1. In this case, the exciton diffusion distance of the exciplex is short, so that the efficiency of the phosphorescent light-emitting layer (light-emitting layer 140) can be maintained. In addition, the fluorescent light-emitting layer (light-emitting layer 120) and the phosphorescent light-emitting layer (light-emitting layer 140) At the interface, a part of the triplet excitation energy of the exciplex of the phosphorescent emitting layer (emitting layer 140) Even if the phosphor diffuses into the fluorescent layer (light-emitting layer 120), the fluorescent light generated by the diffusion The triplet excitation energy of the layer (light-emitting layer 120) is converted to light emission through TTA, It is possible to reduce energy loss.

[0354] As described above, the light emitting device 262 uses ExTET for the light emitting layer 140 and By using TTA in 20, energy loss is reduced, resulting in high luminous efficiency. As shown in the light-emitting element 262, the light-emitting layer 120 and the light-emitting layer In the case where the heat exchanger 140 and the heat exchanger 141 are in contact with each other, the energy loss is reduced and the E The number of L layers 100 can be reduced. Therefore, the light-emitting device can be manufactured at low cost. It can be said that:

[0355] The light-emitting layer 120 and the light-emitting layer 140 may not be in contact with each other. In this case, the organic compound 141_1, the organic compound 141_2, or The guest material 142 (phosphorescent compound) is excited to the host material 121 in the light-emitting layer 120. , or energy transfer to the guest material 122 (fluorescent compound) via the Dexter mechanism ( In particular, triplet energy transfer can be prevented. The layer between the substrate 40 and the substrate 40 may have a thickness of about several nm. If it is equal to or less, an increase in the driving voltage can be suppressed, which is preferable.

[0356] The layer provided between the light-emitting layer 120 and the light-emitting layer 140 may be made of a single material. Alternatively, both a hole transporting material and an electron transporting material may be included. In this case, a bipolar material may be used. The mobility ratio of the hole transport material to the electron transport material is 100 or less. Alternatively, at least one of them may be a host material for the light-emitting layer 140. Even if it is formed from the same material as the substrate material (organic compound 141_1 or organic compound 141_2), This makes it easier to fabricate the light-emitting device and reduces the driving voltage. The hole transporting material and the electron transporting material may form an exciplex, which can generate excitons. Specifically, the host material (organic compound) of the light-emitting layer 140 can be effectively prevented from diffusing. Substance 141_1 or organic compound 141_2) or guest material 142 (phosphorescent compound) The host material 121 or guest material 122 (fluorescent compound) of the light-emitting layer 120 is excited from the excited state. This can prevent the transfer of energy to the

[0357] In the light-emitting element 262, the light-emitting layer 120 is on the hole transport layer 112 side, and the light-emitting layer 140 is on the hole transport layer 112 side. However, the light-emitting element of one embodiment of the present invention is not limited to this. 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 okay.

[0358] In the light emitting device 262, the recombination region of the carriers is formed with a certain degree of distribution. Therefore, it is preferable that the light-emitting layer 120 or the light-emitting layer 140 has an appropriate carrier. The guest material 142 (phosphorescent compound) contained in the light-emitting layer 140 preferably has an attracting property. It is preferable that the gate compound of the light-emitting layer 120 has an electron trapping property. It is preferable that the storage material 122 (fluorescent compound) has a hole trapping property.

[0359] The emission from the light-emitting layer 120 has a peak on the shorter wavelength side than the emission from the light-emitting layer 140. It is preferable that the light emitting device has a phosphorescent compound that emits light of a short wavelength. Optical elements tend to deteriorate quickly in brightness. Therefore, by using fluorescent light for short wavelengths, As a result, a light-emitting element with little deterioration in luminance can be provided.

[0360] In addition, by obtaining light of different emission wavelengths from the light emitting layer 120 and the light emitting layer 140, multicolor The light emitting element may have different emission peaks in the emission spectrum. Since the emitted light is composite, the emission spectrum has at least two maxima. .

[0361] The above-mentioned structure is also suitable for obtaining white light emission. By making the lights of these two colors complementary to each other, white light can be emitted.

[0362] In addition, one or both of the light emitting layers 120 and 140 may have different emission wavelengths. By using multiple luminescent materials, it is possible to produce high-quality color rendering with three primary colors or four or more luminescent colors. In this case, the light-emitting layer is divided into layers, and each of the layers is divided into Each layer may contain a different light emitting material.

[0363] <Examples of materials that can be used for the light-emitting layer> Next, materials that can be used for the light-emitting layer 120 and the light-emitting layer 140 will be described below. do.

[0364] <Materials that can be used for the light-emitting layer 120> In the light-emitting layer 120, the host material 121 is present in the largest amount by weight, and the guest material 122 The fluorescent compound is dispersed in the host material 121. The S1 level of the host material 121 is , which is higher than the S1 level of the guest material 122 (fluorescent compound) and the T1 level of the host material 121. The T1 level is preferably lower than the T1 level of the guest material 122 (fluorescent compound).

[0365] In the light-emitting layer 120, the guest material 122 is not particularly limited, but may be anthracene. Derivatives, tetracene derivatives, chrysene derivatives, phenanthrene derivatives, pyrene derivatives, Rylene derivatives, stilbene derivatives, acridone derivatives, coumarin derivatives, phenoxazine Derivatives, phenothiazine derivatives, etc. are preferred. The indicated fluorescent compounds can be used.

[0366] In addition, examples of materials that can be used as the host material 121 in the light-emitting layer 120 include: Although there is no particular limitation, 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-quinolinolato)(4-phenylphenolato) ) Aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II)( Abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolato]zinc(II)( abbreviation: ZnBTZ), and other metal complexes, such as 2-(4-biphenylyl)-5-(4-tert- butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5 -(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene Zene (abbreviation: OXD-7), 3-(4-biphenylyl)-4-phenyl-5-(4-tetraphenyl) 2,2',2' rt-Butylphenyl)-1,2,4-triazole (abbreviation: TAZ) '-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazo TPBI, bathophenanthroline (BPhen), bathocuproline BCP, 9-[4-(5-phenyl-1,3,4-oxadiazole-2- Heterocyclic compounds such as 4,4-phenyl-9H-carbazole (abbreviation: CO11), '-Bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB or is 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 Aromatic amine compounds such as bis(phenylene phosphate phosphate) and bis(phenylene phosphate phosphate). Nanthrene derivatives, pyrene derivatives, chrysene derivatives, dibenzo[g,p]chrysene derivatives Condensed polycyclic aromatic compounds such as 9,10-diphenylanthracene are specifically exemplified. (abbreviation: DPAnth), N,N-diphenyl-9-[4-(10-phenyl-9-anth tolyl)phenyl]-9H-carbazol-3-amine (abbreviation: CzA1PA), 4-( 10-phenyl-9-anthryl)triphenylamine (abbreviation: DPhPA), 4-(9 H-Carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenyl YGAPA, N,9-diphenyl-N-[4-(10-phenyl-9 -anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), ,9-diphenyl-N-{4-[4-(10-phenyl-9-anthryl)phenyl]furan N,9-diphenyl}-9H-carbazol-3-amine (abbreviation: PCAPBA), N-(9,10-diphenyl-2-anthryl)-9H-carbazol-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 0-Phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: CzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthryl)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'-Bianthryl (abbreviation: BANT), 9,9'-(styryl Ben-3,3'-diyl)diphenanthrene (abbreviation: DPNS), 9,9'-(stilbe 1,3,5-triphenyl-4,4'-diyl)diphenanthrene (abbreviation: DPNS2), -pyrenyl)benzene (abbreviation: TPB3). Among known substances, a substance having an energy gap larger than that of the guest material 122 is selected. One or more types of material having gaps may be selected and used.

[0367] The light-emitting layer 120 may be composed of two or more layers. When the light-emitting layer 120 is formed by laminating the first light-emitting layer and the second light-emitting layer in this order from the hole transport layer side, A substance having a hole transporting property is used as a host material for the first light-emitting layer, and a substance having a hole transporting property is used as a host material for the second light-emitting layer. For example, a substance having an electron transport property is used as the insulating film.

[0368] In the light-emitting layer 120, the host material 121 is composed of a single compound. Alternatively, the light-emitting layer 120 may be made of a single compound or a plurality of compounds. The layer may contain materials other than the host material 121 and the guest material 122 .

[0369] Furthermore, the light-emitting layer 120 may have the configuration of the light-emitting layer shown in the first embodiment. It is preferable to use the host material and the light-emitting material (fluorescent compound) shown in the first embodiment. stomach.

[0370] <Materials that can be used for the light-emitting layer 140> In the light-emitting layer 140, the host material 141 is present in the largest amount by weight, and the guest material 142 The phosphorescent compound is dispersed in the host material 141. The T1 level of 1 (organic compound 141_1 and organic compound 141_2) is It is preferable that the T1 level is higher than that of the T1 level of the ion beam.

[0371] Organic compounds 141_1 include zinc and aluminum metal complexes, as well as oxadiazo derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzyl derivatives, Dibenzothiophene derivatives, dibenzofuran derivatives, pyrimidine derivatives, triazine derivatives, pyridine derivatives, bipyridine derivatives, phenanthroline derivatives Other examples include aromatic amines and carbazole derivatives. Specifically, the electron transporting material and the hole transporting material shown in Embodiment 1 are used. It is possible.

[0372] The organic compound 141_2 is a compound capable of forming an exciplex with the organic compound 141_1. Specifically, for example, the combination of the electron transporting material and the hole transporting material shown in the first embodiment is preferable. A transport material can be used. In this case, organic compound 141_1 and organic compound 141 The emission peak of the exciplex formed with _2 is triplet of the guest material 142 (phosphorescent compound). Term MLCT (Metal to Ligand Charge Transfer) transition The absorption band of organic compound 141_ is overlapped with that of the longest wavelength side, more specifically, 1, an organic compound 141_2, and a guest material 142 (phosphorescent compound) can be selected. This is preferable. It is possible to obtain a light-emitting element with a dramatically improved luminous efficiency. However, when a thermally activated delayed fluorescent compound is used instead of a phosphorescent compound, the longest wavelength is The long absorption band is preferably a singlet absorption band.

[0373] The guest material 142 (phosphorescent compound) is an iridium, rhodium, or platinum-based Organometallic complexes or metal complexes are included, among which organic iridium complexes, e.g. iridium The orthometalated ligand is preferably a 4H-triazolium complex. 1H-triazole ligands, 1H-triazole ligands, imidazole ligands, pyridine ligands, pyrimidine ligands Examples of the ligands include quinolinone, pyrazine, and isoquinoline. Examples of the platinum complex include a platinum complex having a porphyrin ligand. The phosphorescent compound exemplified as the light-emitting material in Embodiment 1 can be used.

[0374] The light-emitting material contained in the light-emitting layer 140 is a material capable of converting triplet excitation energy into light emission. As a material capable of converting the triplet excitation energy into light emission, a phosphorescent material In addition to the compounds, thermally activated delayed fluorescent substances can be mentioned. The term "thermally activated delayed phosphor" may be used instead.

[0375] In addition, materials that exhibit thermally activated delayed fluorescence can be independently converted from a triplet excited state to a single excited state by reverse intersystem crossing. The material may be capable of generating a doublet excited state, or may be an exciplex (or The material may be made of multiple materials that form a single layer (also called an exciplex).

[0376] When the thermally activated delayed phosphor is composed of one kind of material, specifically, It is possible to use a thermally activated delayed phosphor represented by the following formula:

[0377] In addition, when a thermally activated delayed fluorescent substance is used as a host material, two types of exciplexes are formed. In this case, the above-mentioned exciplex is formed. The combination of a compound that easily accepts electrons and a compound that easily accepts holes is It is particularly preferable to use

[0378] In addition, there is no limitation on the color of light emitted by the light-emitting materials contained in the light-emitting layers 120 and 140. They may be the same or different. The light emitted from each is mixed and extracted from the device. Therefore, for example, if the emission colors of the two elements are complementary to each other, the light-emitting element will emit white light. In consideration of the reliability of the light-emitting device, the light-emitting material contained in the light-emitting layer 120 The emission peak wavelength is preferably shorter than that of the light-emitting material contained in the light-emitting layer 140 .

[0379] The light-emitting unit 208, the light-emitting unit 210, and the charge generating layer 115 are formed by deposition ( (including vacuum deposition), inkjet printing, coating, gravure printing, etc. can be done.

[0380] The configuration described in this embodiment mode may be used in appropriate combination with the configurations described in other embodiments. There can be.

[0381] (Embodiment 3) In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS. Reveal.

[0382] <Display device configuration example 1> FIG. 17A is a top view showing the display device 600, and FIG. 17B is a diagram showing the display device 600 shown in FIG. The display device 600 includes a driving circuit section ( The display device includes a signal line driver circuit portion 601, a scanning line driver circuit portion 603, and a pixel portion 602. The signal line driver circuit section 601, the scanning line driver circuit section 603, and the pixel section 602 are It has the function of controlling the light emission of the element.

[0383] The display device 600 includes an element substrate 610, a sealing substrate 604, a sealant 605, The semiconductor device has an area 607 surrounded by a sealing material 605, wiring 608, and an FPC 609. do.

[0384] The lead wiring 608 is connected to the signal line driver circuit portion 601 and the scanning line driver circuit portion 603. This is the wiring for transmitting the input signal. It is connected to the external input terminal FPC609 and It receives the FP signal, clock signal, start signal, reset signal, etc. Although only C609 is shown, FPC609 has a printed wiring board (PWB: Pri A 3.5V DC Inverter Wiring Board may be installed.

[0385] The signal line driver circuit portion 601 includes an N-channel transistor 623 and a P-channel A CMOS circuit is formed by combining this transistor 624. The path section 601 or the scanning line driving circuit section 603 may be implemented by various CMOS circuits, PMOS circuits, or In this embodiment, the driving circuit section is formed on the substrate. Although the display device shown has the driver and the pixels formed on the same surface, this is not necessarily required. Alternatively, the driving circuitry may be formed externally rather than on the substrate.

[0386] The pixel portion 602 includes a switching transistor 611 and a current control transistor 612. A lower part electrically connected to the drain of the transistor 612 for current control A partition wall 614 is formed to cover an end of the lower electrode 613. The partition wall 614 can be made of a positive photosensitive acrylic resin film.

[0387] In order to improve the covering property, the partition wall 614 is provided with a curved surface having a curvature at the upper end or the lower end. For example, a positive photosensitive acrylic is used as the material for the partition wall 614. In this case, only the upper end of the partition wall 614 is curved with a radius of curvature (0.2 μm or more and 3 μm or less). It is preferable that the partition wall 614 is made of a negative photosensitive resin or a polyimide. Any of the above-mentioned photosensitive resins can be used.

[0388] The structure of the transistors (transistors 611, 612, 623, and 624) is For example, a staggered transistor may be used. There is no particular limitation on the polarity, and it has N-channel and P-channel transistors. The structure is such that the transistors are either N-channel or P-channel. A structure consisting of only one of the two may be used. For example, an amorphous semiconductor film or a crystalline semiconductor film may be used. Semiconductor materials include group 14 (silicon, etc.) semiconductors, compound semiconductors (oxide As the transistor, for example, The energy gap is 2 eV or more, preferably 2.5 eV or more, and more preferably 3 eV or more. By using the oxide semiconductor, the off-state current of a transistor can be reduced. As the oxide semiconductor, 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 neodymium (Nb). Examples include Nd (Nd).

[0389] An EL layer 616 and an upper electrode 617 are formed on the lower electrode 613. For example, the lower electrode 613 functions as an anode and the upper electrode 617 functions as a cathode. do.

[0390] The EL layer 616 is formed by a deposition method (including a vacuum deposition method) using a deposition mask, a droplet discharge method, etc. (also called inkjet method), spin coating method, gravure printing method, etc. The EL layer 616 is formed by the method. The material for forming the EL layer 616 is a low molecular weight compound, Alternatively, it may be a polymer compound (including an oligomer or a dendrimer).

[0391] The lower electrode 613, the EL layer 616, and the upper electrode 617 constitute a light-emitting element 618. The light emitting element 618 has the configurations of the first and second embodiments. In addition, in the case where a plurality of light emitting elements are formed in a pixel portion, The light-emitting element according to the second embodiment and the light-emitting element having other structures are both included. That's fine.

[0392] In addition, the sealing substrate 604 is bonded to the element substrate 610 with the sealant 605, A light-emitting element is disposed in an area 607 surrounded by an element substrate 610, a sealing substrate 604, and a sealant 605. The region 607 is filled with a filler. In addition to being filled with an inert gas (nitrogen, argon, etc.), it can also be used as a sealant 605. They may also be filled with UV-curable or heat-curable resins, e.g. PVC ( Polyvinyl chloride) resin, acrylic resin, polyimide resin, epoxy resin, Silicone resin, PVB (polyvinyl butyral) resin, or EVA (ethylene vinyl acetate) In addition, silicon oxide, silicon oxynitride, Inorganic materials such as silicon oxynitride, silicon nitride, aluminum oxide, and aluminum nitride If a recess is formed in the sealing substrate and a desiccant is provided there, deterioration caused by moisture can be prevented. This is a preferable configuration because it is possible to suppress the oxidation of the surface of the substrate. The impurities are effectively prevented from penetrating from the outside of the display device 600 to the light emitting element 618 inside the display device. In order to prevent this, it is preferable to laminate a resin and an inorganic material. A structure in which the sealant 605 or the sealing substrate 604 is not provided may be used.

[0393] In addition, an optical element is provided below the element substrate 610 so as to overlap the light emitting element 618. The optical element may have the same structure as the optical element shown in the first embodiment.

[0394] It is preferable to use epoxy resin or glass frit for the sealing material 605. In addition, it is desirable that these materials are as impermeable to moisture and oxygen as possible. In addition, the material used for the sealing substrate 604 may be a glass substrate, a quartz substrate, or FRP (Fiber Reinforced Plastics). Reinforced Plastics), PVF (Polyvinyl Fluoride), Poly A plastic substrate made of ester, acrylic or the like can be used.

[0395] <Method for forming light-emitting element by droplet ejection method> Here, a method for forming the EL layer 616 by using a droplet discharge method will be described with reference to FIG. 20(A) to 20(D) are cross-sectional views illustrating a method for forming the EL layer 616. be.

[0396] First, in FIG. 20A, a device substrate on which a lower electrode 613 and a partition wall 614 are formed is shown. 610 is shown, but as shown in FIG. 17B, a lower electrode 613 and a partition wall 61 are formed on the insulating film. A substrate on which 4 is formed may also be used.

[0397] Next, a droplet is discharged from a droplet discharge device 683 to an exposed portion of the lower electrode 613, which is an opening of the partition wall 614. Droplets 684 are ejected to form a layer 685 containing the composition. The droplets 684 are a layer of the composition containing a solvent. It is attached onto the lower electrode 613 (see FIG. 20(B)).

[0398] The step of discharging the droplets 684 may be performed under reduced pressure.

[0399] Next, the solvent is removed from the layer 685 containing the composition, and the layer is solidified to form the EL layer 616. (See FIG. 20(C)).

[0400] The solvent may be removed by a drying step or a heating step.

[0401] Next, an upper electrode 617 is formed on the EL layer 616 to form a light-emitting element 618 (FIG. 20 (See (D)).

[0402] In this way, when the EL layer 616 is formed by the droplet discharge method, the composition can be selectively discharged. This reduces material loss. Since no additional steps are required, the process can be simplified and costs can be reduced.

[0403] In FIG. 20, a process for forming the EL layer 616 in a single layer has been described. When the light-emitting layer 16 has a functional layer in addition to the light-emitting layer, each layer is formed in order from the lower electrode 613 side. In this case, the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer are The hole injection layer, the hole transport layer, and the light emitting layer may be formed by the droplet discharge method. The electron transport layer and the electron injection layer may be formed by a deposition method or the like. The layer may be formed by a droplet discharge method, a vapor deposition method, or the like.

[0404] The hole injection layer may be, for example, poly(ethylenedioxythiophene) / poly(styrene The insulating film 10 can be formed by using a coating method such as a droplet discharge method or a spin coating method. The hole transport layer can be formed of a hole transport material, for example, poly Vinyl carbazole can be formed by using a coating method such as a droplet discharge method or a spin coating method. After the formation of the hole injection layer and the hole transport layer, the hole injection layer and the hole transport layer are heated in an air atmosphere or in an atmosphere such as nitrogen. Each of the layers may be subjected to a heat treatment under an inert gas atmosphere.

[0405] The light-emitting layer can be purple, blue, blue-green, green, yellow-green, yellow, orange, or red. The light-emitting device is formed by at least one luminescent polymer compound or low molecular compound selected from the group consisting of The high molecular weight compounds and low molecular weight compounds can be used as the fluorescent or phosphorescent compounds. Light-emitting organic compounds can be used. Polymer compounds and low molecular weight compounds can be used in a solvent. By dissolving the film, it can be formed by a coating method such as a droplet discharge method or a spin coating method. After the light-emitting layer is formed, the layer is heated in air or in an inert gas atmosphere such as nitrogen. In addition, a fluorescent or phosphorescent organic compound may be used as a guest material. The guest material is dispersed in a polymer or low molecular weight compound that has a higher excitation energy than the material. The light-emitting organic compound may be formed alone or in a mixture with other substances. The light-emitting layer may be formed in two layers. The light-emitting layers preferably contain light-emitting organic compounds that emit light of different colors. In addition, when a low molecular weight compound is used for the light emitting layer, the layer can be formed by a deposition method. .

[0406] The electron transport layer can be formed by depositing a substance having a high electron transport property. The electron injection layer can be formed by depositing a material having a high electron injection property. The electron transport layer and the electron injection layer can be formed by vapor deposition.

[0407] The upper electrode 617 can be formed by using a deposition method. The upper electrode 617 can be formed using a conductive film having reflectivity. A conductive film having reflectivity and a conductive film having light-transmitting properties may be stacked.

[0408] The droplet discharge method described above is a method of discharging a composition using a nozzle having a discharge port, or The term "jet head" is a general term for anything that has a means for ejecting droplets, such as a head having multiple nozzles.

[0409] ≪Droplet discharge device≫ Next, a droplet discharge device used in the droplet discharge method will be described with reference to FIG. 14 is a conceptual diagram illustrating a droplet ejection device 1400. FIG.

[0410] The droplet discharge device 1400 includes a droplet discharge means 1403. 3 has a head 1405 and a head 1412.

[0411] The head 1405 and the head 1412 are connected to a control means 1407, which controls a computer. By controlling the laser 1410, it is possible to draw a pre-programmed pattern. can.

[0412] The timing of drawing may be, for example, marker 1 formed on the substrate 1402. Alternatively, the reference point may be determined based on the outer edge of the substrate 1402. Here, the marker 1411 is detected by the imaging means 1404, and the image processing means 1 The signal converted to a digital signal by 409 is recognized by a computer 1410 and a control signal is generated. The generated signal is sent to the control means 1407.

[0413] The imaging means 1404 may be a charge-coupled device (CCD) or a complementary metal oxide semiconductor (CM An image sensor using an OS can be used. The information of the pattern to be created is stored in the storage medium 1408. A control signal is sent to the control means 1407, and the individual heads 1405, The material to be discharged is supplied from a material supply source 1413, a material supply unit 1414, and a nozzle 1416. The fuel is supplied from a fuel supply source 1414 through piping to heads 1405 and 1412, respectively. do.

[0414] The inside of the head 1405 is a space 1406 for filling with a liquid material, as shown by the dotted line, and a discharge space 1405 for discharging the liquid material. The head 1412 has a nozzle as an outlet. The head 1405 and the head 1412 have the same internal structure. By providing a single head, different materials can be printed at different widths at the same time. It is possible to discharge multiple types of luminescent materials and perform drawing on a wide area. In order to improve throughput, the same material is ejected from multiple nozzles at the same time to create a pattern. When a large substrate is used, the head 1405 and the head 1412 move over the substrate as shown in FIG. 1) The area to be drawn can be freely set by freely scanning in the directions of the X, Y, and Z arrows shown in the figure. This allows the same pattern to be written multiple times on a single substrate.

[0415] The step of discharging the composition may be carried out under reduced pressure. After the composition is discharged, one or both of the steps of drying and baking are performed. Both processes are heat treatment processes, but the purpose, temperature and time are different. The firing process is carried out under normal or reduced pressure by laser light irradiation, instantaneous thermal annealing, or a heating furnace. The timing of the heat treatment and the number of times the heat treatment is performed are not particularly limited. In order to perform the drying and baking processes well, the temperature at which they are performed depends on the material of the substrate and the properties of the composition. Depends on.

[0416] As described above, the EL layer 616 can be manufactured using a droplet discharge apparatus.

[0417] As described above, a display device having the light emitting device according to the first and second embodiments is provided. can be obtained.

[0418] <Display device configuration example 2> Next, another example of the display device will be described with reference to FIGS. 18(A)(B) and 19. 18A, 18B, and 19 are cross-sectional views of a display device according to one embodiment of the present invention. .

[0419] FIG. 18A shows a substrate 1001, an insulating base film 1002, a gate insulating film 1003, and a gate Electrodes 1006, 1007, 1008, a first interlayer insulating film 1020, a second interlayer insulating film 10 21, peripheral portion 1042, pixel portion 1040, driving circuit portion 1041, lower electrode 10 of light emitting element 24W, 1024R, 1024G, 1024B, partition 1025, EL layer 1028, light emitting element The upper electrode 1026 of the device, the sealing layer 1029, the sealing substrate 1031, the seal material 1032, etc. are shown in FIG. As shown.

[0420] In FIG. 18A, a colored layer (a 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 be further provided. The base material 1033 is aligned and fixed to the substrate 1001. is covered with an overcoat layer 1036. In FIG. 1034R transmits red light, colored layer 1034G transmits green light, and colored layer 1034 B has the function of transmitting blue light.

[0421] In FIG. 18B, as an example of an optical element, a colored layer (a red colored layer 1034R, a green colored layer The colored layer 1034G and the blue colored layer 1034B are formed between the gate insulating film 1003 and the first interlayer insulating film. In this example, the colored layer is formed between the substrate 1001 and the film 1020. It may be provided between the substrates 1031 .

[0422] In FIG. 19, as an example of an optical element, a colored layer (a red colored layer 1034R, a green colored layer 1034G, blue colored layer 1034B) are formed between the first interlayer insulating film 1020 and the second interlayer insulating film In this example, the colored layer is formed between the substrate 1001 and the sealing substrate 1021. It may be provided between the plates 1031.

[0423] In addition, the display device according to one embodiment of the present invention can display four colors (red, green, blue, yellow, or red, A display device having sub-pixels of three colors (green, blue, and white). Since the light-emitting element has high light-emitting efficiency, a display device having a yellow or white subpixel consumes less power. can be reduced.

[0424] The lower electrode 1024W preferably has a function of transmitting light. An upper electrode 1026 is provided on the substrate 28. The upper electrode 1026 has a function of reflecting light. In addition, the lower electrodes 1024R, 1024G, and 1024B are preferably light-transmitting. The lower electrodes 1024R, 1024G, and 1024B have a function of transmitting light and a function of reflecting light. A microcavity structure is adopted between the upper electrode 1026 and the light intensity at a specific wavelength. It is preferable to increase the degree.

[0425] 18 and 19, a plurality of light emitting elements and Although the configuration in which a colored layer is provided has been illustrated, the present invention is not limited to this. For example, a red colored layer 1034 R, a configuration in which none of the green coloring layer 1034G and the blue coloring layer 1034B is provided. When a colored layer is provided on each of the light emitting elements, reflection of external light can be suppressed. On the other hand, when a colored layer is not provided, the light emitted from the light emitting element Since the loss of light is small, power consumption can be reduced.

[0426] In the display device described above, the side of the substrate 1001 on which the transistors are formed is The display device has a bottom emission structure for extracting light. The display device may also have a structure for extracting emitted light (top emission type).

[0427] The sealing substrate 1031 only needs to have a function of protecting the light-emitting element. Therefore, the sealing substrate 1031 can be a flexible substrate or film.

[0428] Note that the configuration shown in this embodiment may be appropriately combined with other embodiments or other configurations in this embodiment. Combinations are possible.

[0429] (Embodiment 4) In this embodiment, a display device including a light-emitting device according to one embodiment of the present invention will be described with reference to FIGS. The explanation will be given with reference to FIG.

[0430] Note that FIG. 22A is a block diagram illustrating a display device of one embodiment of the present invention. 2(B) is a circuit diagram illustrating a pixel circuit included in a display device of one embodiment of the present invention.

[0431] <Explanation about the display device> The display device shown in FIG. 22A has a region having pixels of a display element (hereinafter, referred to as a pixel portion 802). ) and a circuit section ( hereinafter referred to as a drive circuit section 804) and a circuit having a function of protecting the element (hereinafter referred to as a protection circuit 80 6) and a terminal portion 807. Note that the protection circuit 806 is not provided. This is also fine.

[0432] A part or the whole of the driver circuit portion 804 is formed on the same substrate as the pixel portion 802. This makes it possible to reduce the number of parts and terminals. When a part or the whole of the pixel portion 802 is not formed on the same substrate, the driving circuit A part or the whole of the path portion 804 is COG or TAB (Tape Automated Band). It can be implemented by using the onding.

[0433] The pixel section 802 is arranged in X rows (X is a natural number of 2 or more) and Y columns (Y is a natural number of 2 or more). A circuit for driving a plurality of display elements (hereinafter referred to as pixel circuit 801) is provided. The path portion 804 is a circuit that outputs a signal (scanning signal) for selecting a pixel (hereinafter, a scanning line driving circuit 804a) to supply signals (data signals) for driving the display elements of the pixels. The image display device 804 includes driver circuits such as a circuit (hereinafter, a signal line driver circuit 804b).

[0434] The scanning line driver circuit 804a includes a shift register and the like. A signal for driving the shift register is input via a terminal portion 807, and a signal is output. For example, a start pulse signal, a clock signal, etc. are input to the scanning line driver circuit 804a. The scanning line driver circuit 804a is a wiring to which a scanning signal is applied (hereinafter, The scanning lines GL_1 to GL_X are connected to the ground. A plurality of driving circuits 804a are provided, and the scanning lines GL_1 to Alternatively, the scanning line driving circuit 804a may control the GL_X by dividing it. However, the present invention is not limited to this, and the scanning line driving circuit 80 4a may also provide another signal.

[0435] The signal line driver circuit 804b includes a shift register and the like. Through the terminal portion 807, a signal for driving the shift register and a source of a data signal are input. The signal line driver circuit 804b drives the pixel circuit based on the image signal. The signal line driver circuit 804b has a function of generating a data signal to be written to the signal line driver circuit 801. A data signal is generated according to a pulse signal obtained by inputting a start pulse, a clock signal, etc. The signal line driver circuit 804b has a function of controlling the output of a data signal. The data lines DL_1 to DL_Y are connected to the data line 101 through the data line 102. Alternatively, the signal line driver circuit 804b may have a function of supplying an initialization signal. However, the present invention is not limited to this, and the signal line driver circuit 804b may also supply other signals. It is possible.

[0436] The signal line driver circuit 804b is configured using, for example, a plurality of analog switches. The signal line driver circuit 804b sequentially turns on a plurality of analog switches, The image signal can be time-division-multiplexed and output as a data signal. Also, a shift register, etc. The signal line driver circuit 804b may be formed using the same.

[0437] Each of the plurality of pixel circuits 801 is connected to one of the plurality of scanning lines GL to which a scanning signal is applied. A pulse signal is inputted through the data line DL, and a data signal is given through one of the data lines DL. A data signal is input to each of the pixel circuits 801 via a scanning line driving circuit. 804a controls writing and holding of data of the data signal. For example, The second pixel circuit 801 is connected to a scanning line drive circuit via a scanning line GL_m (m is a natural number equal to or smaller than X). A pulse signal is input from 804a, and the potential of the data line DL_n ( A data signal is input from the signal line driver circuit 804b via a data line driver 804c (n is a natural number equal to or smaller than Y).

[0438] The protection circuit 806 shown in FIG. 22A is, for example, a scanning line driver circuit 804a and a pixel circuit 8 01. Alternatively, the protection circuit 806 is connected to the scanning line GL, which is the wiring between the signal line driver The data line DL is connected between the circuit 804b and the pixel circuit 801. The protection circuit 806 can be connected to a wiring between the scanning line driver circuit 804a and the terminal portion 807. Alternatively, the protection circuit 806 may be a wiring between the signal line driver circuit 804b and the terminal portion 807. The terminal portion 807 can be connected to a power supply and a line from an external circuit to the display device. This refers to the part provided with terminals for inputting control signals and image signals.

[0439] When a potential outside a certain range is applied to the wiring to which the protection circuit 806 is connected, the protection circuit This is a circuit that brings one wire into electrical continuity with another wire.

[0440] As shown in FIG. 22A, a pixel section 802 and a driver circuit section 804 are provided with a protection circuit 80. 6, ESD (Electro Static Discharge) The resistance of the display device to overcurrent caused by electrostatic discharge (ESD) and other phenomena can be improved. However, the configuration of the protection circuit 806 is not limited to this. For example, or a configuration in which the protection circuit 806 is connected to the signal line driver circuit 804b. Alternatively, a protection circuit 806 may be connected to the terminal portion 807. It can also be composed of

[0441] In FIG. 22A, the scanning line driver circuit 804a and the signal line driver circuit 804b Therefore, although an example in which the driver circuit portion 804 is formed is shown, the present invention is not limited to this configuration. For example, only the scanning line driver circuit 804a is formed, and a signal line driver circuit is separately formed. A substrate (for example, a drive circuit substrate formed of a single crystal semiconductor film or a polycrystalline semiconductor film) is mounted. It may also be configured as follows.

[0442] <Pixel circuit configuration example> The pixel circuits 801 shown in FIG. 22(A) may have a configuration shown in FIG. 22(B), for example. It is possible.

[0443] The pixel circuit 801 shown in FIG. 22B includes transistors 852 and 854 and a capacitor 86. 2 and a light-emitting element 872.

[0444] A data signal is applied to one of the source and drain electrodes of the transistor 852. The gate of the transistor 852 is electrically connected to the wiring (data line DL_n). The electrode is electrically connected to a wiring (scanning line GL_m) to which a gate signal is applied.

[0445] The transistor 852 has a function of controlling writing of data signals.

[0446] One of a pair of electrodes of the capacitor 862 is connected to a wiring to which a potential is applied (hereinafter, a potential supply line VL _a), and the other is electrically connected to the source electrode and drain electrode of the transistor 852. The second electrode is electrically connected to the other of the first and second electrodes.

[0447] The capacitor 862 functions as a storage capacitor for storing written data.

[0448] One of the source electrode and the drain electrode of the transistor 854 is connected to the potential supply line VL_a. In addition, the gate electrode of the transistor 854 is electrically connected to the It is electrically connected to the other of the source electrode and the drain electrode.

[0449] One of the anode and the cathode of the light-emitting element 872 is electrically connected to the potential supply line VL_b. The other one is electrically connected to the other of the source electrode and the drain electrode of the transistor 854. will be done.

[0450] The light-emitting element 872 has the structure of the light-emitting element described in Embodiments 1 and 2. It is possible.

[0451] A high power supply potential VDD is applied to one of the potential supply lines VL_a and VL_b. and the other is supplied with a low power supply potential VSS.

[0452] In a display device having the pixel circuit 801 shown in FIG. 22B, for example, The pixel circuits 801 in each row are selected in sequence by the scanning line driving circuit 804a, and the transistors 852 are turned on. The data signal is written by turning it on.

[0453] In the pixel circuit 801 to which the data has been written, the transistor 852 is turned off. Furthermore, the transistor 854 is in a holding state in response to the potential of the written data signal. The amount of current flowing between the source electrode and the drain electrode is controlled, and the light emitting element 872 The light is emitted with a brightness that corresponds to the flow rate. By performing this process row by row, an image can be displayed.

[0454] In addition, the pixel circuit has a function to correct the effects of fluctuations in the threshold voltage of transistors, etc. 23(A)(B) and 24(A)(B) show an example of a pixel circuit.

[0455] The pixel circuit shown in FIG. 23A includes six transistors (transistors 303_1 to 303_3). 303_6), a capacitor 304, and a light-emitting element 305. In the pixel circuit shown in FIG. The transistors 303_1 to 303_6 are electrically connected to each other. For example, a P-channel transistor can be used.

[0456] The pixel circuit shown in FIG. 23B is the pixel circuit shown in FIG. 23A, except that a transistor 303 is added. In addition, the pixel circuit shown in FIG. 23B includes a wiring 301_6 and The wiring 301_5 and the wiring 301_6 are electrically connected to each other. may be electrically connected to each other. For example, a P-channel transistor can be used.

[0457] The pixel circuit shown in FIG. 24A includes six transistors (transistors 308_1 to 308_3). 308_6), a capacitor 304, and a light-emitting element 305. The pixel circuit shown in FIG. Here, the wiring 306_1 and the wiring 306_3 are electrically connected to each other. The transistors 308_1 to 308_6 may be electrically connected to each other. For example, a P-channel transistor can be used.

[0458] The pixel circuit shown in FIG. 24B includes two transistors (transistor 309_1 and transistor transistor 309_2) and two capacitive elements (capacitive element 304_1 and capacitive element 304_ 2) and a light-emitting element 305. In addition, the pixel circuit shown in FIG. 11_1 to 311_3, the wiring 312_1, and the wiring 312_2 are electrically connected to each other. In addition, by configuring the pixel circuit as shown in FIG. 24(B), for example, The transistor 309 can be a current-driven type (also called a CVCC type). For example, a P-channel transistor can be used for 1 and 309_2. .

[0459] In addition, the light-emitting element of one embodiment of the present invention may be an active master having an active element in a pixel of a display device. A display device that uses a trix method or a passive matrix method that does not have active elements in the pixels of the display device. It can be applied to each method.

[0460] In the active matrix method, a transistor is used as an active element (active element, nonlinear element). By using not only transistors but also various active elements (active elements, nonlinear elements), For example, MIM (Metal Insulator Metal) or T It is also possible to use FD (Thin Film Diode) and other elements. Since the number of manufacturing steps is small, it is possible to reduce manufacturing costs and improve yields. Alternatively, these elements can improve the aperture ratio due to their small size. This makes it possible to achieve low power consumption and high brightness.

[0461] As a non-active matrix type, active elements (active elements, nonlinear elements It is also possible to use a passive matrix type that does not use active elements. Since it does not use any nonlinear elements, there are fewer manufacturing steps, which reduces manufacturing costs and improves yield. It is possible to improve the accuracy. Alternatively, active elements (active elements, nonlinear elements) can be used. Since the aperture ratio is not increased, it is possible to achieve low power consumption and high brightness. It is possible to do this.

[0462] The structure described in this embodiment may be used in appropriate combination with structures described in other embodiments. can be done.

[0463] (Embodiment 5) In this embodiment, a display device including a light-emitting device according to one embodiment of the present invention and a display device including the light-emitting device will be described. An electronic device having an input device attached thereto will be described with reference to FIGS. 25 to 29. FIG.

[0464] <Touch panel explanation 1> In the present embodiment, an electronic device that combines a display device and an input device is used as an example of the electronic device. The touch panel 2000 will be described. The case where the .lambda.

[0465] 25(A) and (B) are perspective views of the touch panel 2000. In B), representative components of touch panel 2000 are shown for clarity.

[0466] The touch panel 2000 includes a display device 2501 and a touch sensor 2595 (see FIG. 2). 5(B)). The touch panel 2000 includes a substrate 2510, a substrate 2570, and a substrate The substrate 2510, the substrate 2570, and the substrate 2590 are all However, any one of the substrates 2510, 2570, and 2590 may be flexible. Alternatively, one or all of the components may be configured to be inflexible.

[0467] The display device 2501 includes a plurality of pixels on a substrate 2510 and a display device that can supply signals to the pixels. The plurality of wirings 2511 are arranged around the periphery of the substrate 2510. The wire is routed through a wire loop, part of which constitutes the terminal 2519. The terminal 2519 is an FPC 2509 (1). In addition, the plurality of wirings 2511 are electrically connected to the signal line driver circuit 2503s ( The signal from 1) can be fed to multiple pixels.

[0468] The substrate 2590 is electrically connected to the touch sensor 2595. The plurality of wirings 2598 are routed around the periphery of the substrate 2590. A part of the terminal is electrically connected to the FPC2509(2). In FIG. 25B, for clarity, the back side of the substrate 2590 (substrate 2510) is shown. The electrodes and wiring of the touch sensor 2595 provided on the surface opposite to the touch panel 2591 are shown by solid lines. .

[0469] As the touch sensor 2595, for example, a capacitive touch sensor can be used. The capacitive type includes a surface type capacitive type and a projected type capacitive type.

[0470] The projected capacitive type is classified into self-capacitance type, mutual capacitance type, etc., mainly based on the difference in the driving method. The mutual capacitance method is preferable because it enables simultaneous multi-point detection.

[0471] The touch sensor 2595 shown in FIG. 25(B) is a projected capacitive touch sensor. This is a configuration in which the .

[0472] The touch sensor 2595 can detect the proximity or contact of a detection target such as a finger. Various sensors can be applied.

[0473] The projected capacitive touch sensor 2595 has an electrode 2591 and an electrode 2592. The electrode 2591 is electrically connected to one of a plurality of wirings 2598, and the electrode 2592 is It is electrically connected to any other of the multiple wirings 2598.

[0474] As shown in FIG. 25(A) and (B), the electrodes 2592 are arranged in a single direction. The shape is such that the four quadrilaterals are connected at their corners.

[0475] The electrode 2591 is quadrilateral and is repeated in a direction intersecting the direction in which the electrode 2592 extends. are placed.

[0476] The wiring 2594 is electrically connected to the two electrodes 2591 that sandwich the electrode 2592. In this case, it is preferable that the area of ​​the intersection between the electrode 2592 and the wiring 2594 is as small as possible. This reduces the area of ​​the region where no electrodes are provided, reducing variations in transmittance. As a result, the variation in the brightness of the light passing through the touch sensor 2595 can be reduced. can be done.

[0477] The shapes of the electrodes 2591 and 2592 are not limited to this, and may take various shapes. For example, multiple electrodes 2591 are arranged with as few gaps as possible, and are A plurality of electrodes 2592 are provided at intervals so that there is an area where the electrodes 2592 do not overlap with the electrodes 2591. In this case, a wire may be provided between two adjacent electrodes 2592, which is electrically isolated from the two adjacent electrodes 2592. Providing an insulated dummy electrode is preferable because it can reduce the area of ​​the region with different transmittance. .

[0478] <Explanation about the display device> Next, the display device 2501 will be described in detail with reference to FIG. ) corresponds to a cross-sectional view taken along dashed line X1-X2 shown in FIG. 25(B).

[0479] The display device 2501 has a plurality of pixels arranged in a matrix. The display device has a display element and a pixel circuit for driving the display element.

[0480] In the following description, a light emitting element that emits white light is used as a display element. However, the display element is not limited to this. For example, Light emitting elements with different luminous colors may be applied so that the colors are different.

[0481] The substrate 2510 and the substrate 2570 may have a water vapor permeability of, for example, 1×10 -5 g· m -2 ·day -1 Less than or equal to 1×10 -6 g m -2 ·day -1 Possible A flexible material can be preferably used. It is preferable to use a material having a coefficient of thermal expansion approximately equal to that of the plate 2570. For example, is 1×10 -3 / K or less, preferably 5×10 -5 / K or less, preferably 1×10 - 5 A material having a viscosity of 0.1 to 1.0 μm may be preferably used.

[0482] The substrate 2510 is made up of an insulating layer 2510a for preventing impurities from diffusing into the light-emitting element, and a flexible The substrate 2510b and the adhesive layer 2 that bonds the insulating layer 2510a and the flexible substrate 2510b together 510c. The substrate 2570 is a laminate having a structure for preventing diffusion of impurities into the light-emitting element. and a flexible substrate 2570b. 2570b and an adhesive layer 2570c that bonds the first and second layers 2570a and 2570b to each other.

[0483] The adhesive layer 2510c and the adhesive layer 2570c may be made of, for example, polyester or polyolefin. Polyimide, polycarbonate or acrylic The resin may be a polyurethane, epoxy, or silicone. Any material containing a resin having a siloxane bond can be used.

[0484] In addition, a sealing layer 2560 is provided between the substrate 2510 and the substrate 2570. It is preferable that the refractive index of the light-emitting layer 2560 is larger than that of air. In this case, the sealing layer 2560 may also serve as an optical bonding layer.

[0485] A sealant may be formed on the outer periphery of the sealing layer 2560. As a result, the area surrounded by the substrate 2510, the substrate 2570, the sealing layer 2560, and the sealant The sealing layer 2560 may include a light emitting element 2550R. An inert gas (such as nitrogen or argon) may be filled. In addition, a desiccant may be added to the inert gas. Alternatively, a resin such as acrylic or epoxy may be used. The sealing material may be, for example, an epoxy resin or It is preferable to use glass frit. In addition, the material used for the sealing material is one that is resistant to moisture and acid. It is preferable to use a material that is opaque to the elements.

[0486] The display device 2501 also has a pixel 2502R. The pixel 2502R is a light-emitting model. It has a Joule 2580R.

[0487] The pixel 2502R includes a light emitting element 2550R and a power supply to the light emitting element 2550R. The transistor 2502t is a transistor that can The light emitting module 2580R includes a light emitting element 2550R and and a colored layer 2567R.

[0488] The light emitting element 2550R includes a lower electrode, an upper electrode, and an EL layer between the lower electrode and the upper electrode. As the light-emitting element 2550R, for example, the light-emitting element shown in Embodiment 1 or 2 can be used. Photonic elements can be applied.

[0489] In addition, a microcavity structure is adopted between the lower electrode and the upper electrode, and at a specific wavelength The light intensity may be increased.

[0490] The colored layer 2567R is located so as to overlap the light emitting element 2550R. A part 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. The light is emitted to the outside of the optical module 2580R.

[0491] Furthermore, the display device 2501 is provided with a light-shielding layer 2567BM in the light emission direction. The light blocking layer 2567BM is provided so as to surround the colored layer 2567R.

[0492] The colored layer 2567R may have a function of transmitting light in a specific wavelength band. For example, a color filter that transmits light in the red wavelength band and a color filter that transmits light in the green wavelength band A color filter that transmits light in the blue wavelength band, and a color filter that transmits light in the yellow wavelength band. A transparent color filter can be used. Each color filter is made of various materials. By using the above, printing method, inkjet method, etching method using photolithography technology, etc. It can be formed by, for example.

[0493] The display device 2501 is provided with an insulating layer 2521. The insulating layer 2521 is provided to flatten the unevenness caused by the pixel circuit. In addition, the insulating layer 2521 has a function of suppressing diffusion of impurities. This prevents the reliability of the transistors 2502t and the like from being reduced due to the diffusion of impurities. It can be suppressed.

[0494] The light emitting element 2550R is formed above the insulating layer 2521. The lower electrode of 550R is provided with a partition wall 2528 that overlaps an edge of the lower electrode. A spacer for controlling the distance between the substrate 2510 and the substrate 2570 is provided on the partition wall 2528. It may be formed.

[0495] The scanning line driver circuit 2503g(1) includes a transistor 2503t and a capacitor element 2503c. The driver circuit and the pixel circuit can be formed on the same substrate in the same process. do.

[0496] Moreover, wiring 2511 capable of supplying signals is provided on the substrate 2510 . A terminal 2519 is provided on the wiring 2511. C2509(1) is electrically connected to FPC2509(1). FPC2509(1) also transmits video signals, It has the function of supplying clock signals, start signals, reset signals, etc. 509(1) may have a printed wiring board (PWB) attached.

[0497] In addition, transistors with various structures can be used in the display device 2501. In 26(A), an example is given of a case where a bottom-gate transistor is applied. However, the present invention is not limited to this. For example, a top gate transistor shown in FIG. 26(B) may be used. The display device 2501 may be configured to use the same.

[0498] In addition, there is no particular restriction on the polarity of the transistor 2502t and the transistor 2503t. There is no fixed definition, and the structure has N-channel and P-channel transistors, A structure consisting of either a P-channel transistor or a P-channel transistor is used. In addition, the crystallinity of the semiconductor film used in the transistors 2502t and 2503t may be For example, an amorphous semiconductor film or a crystalline semiconductor film may be used. In addition, the semiconductor material may be a semiconductor of group 14 (e.g., a semiconductor having silicon). A compound semiconductor (including an oxide semiconductor), an organic semiconductor, etc. can be used. Either or both of the transistor 2502t and the transistor 2503t may be provided with an energy An oxide having a gap of 2 eV or more, preferably 2.5 eV or more, and more preferably 3 eV or more. The use of a semiconductor is preferable because the off-state current of a transistor can be reduced. The oxide semiconductor includes In-Ga oxide, In-M-Zn oxide (where M is Al, a, Y, Zr, La, Ce, Sn, Hf, or Nd).

[0499] <Explanation about touch sensor> Next, the touch sensor 2595 will be described in detail with reference to FIG. 25(C) corresponds to a cross-sectional view taken along dashed line X3-X4 shown in FIG. 25(B).

[0500] The touch sensor 2595 includes electrodes 2591 and electrodes 2592 arranged in a staggered pattern on a substrate 2590. 2592, an insulating layer 2593 covering the electrodes 2591 and 2592, and adjacent electrodes 25 91 and a wiring 2594 that electrically connects them.

[0501] The electrode 2591 and the electrode 2592 are formed using a light-transmitting conductive material. Examples of conductive materials having the above structure include indium oxide, indium tin oxide, and indium zinc oxide. Conductive oxides such as zinc oxide, zinc oxide doped with gallium can be used. A film containing graphene may also be used. The film containing graphene may be, for example, a film-like The graphene oxide-containing film formed on the substrate can be reduced to form the graphene oxide-containing film. An example of such a method is the application of heat.

[0502] For example, a light-transmitting conductive material is formed on the substrate 2590 by a sputtering method. After that, various pattern forming techniques such as photolithography are used to remove unnecessary parts. , an electrode 2591 and an electrode 2592 can be formed.

[0503] The insulating layer 2593 may be made of a material such as acrylic resin or epoxy resin. In addition to resins with siloxane bonds such as silicone, silicon oxide, oxynitride, etc. Inorganic insulating materials such as silicon and aluminum oxide can also be used.

[0504] In addition, an opening reaching the electrode 2591 is provided in the insulating layer 2593, and a wiring 2594 is adjacent to the insulating layer 2593. The transparent conductive material is used to increase the aperture ratio of the touch panel. Since the electrode 2591 can be formed by the above-mentioned method, it can be suitably used for the wiring 2594. A material having a higher electrical conductivity than the electrode 2592 is preferable for the wiring 2594 because it can reduce electrical resistance. It can be used appropriately.

[0505] The electrodes 2592 extend in one direction, and a plurality of electrodes 2592 are provided in a stripe pattern. In addition, the wiring 2594 is provided so as to intersect with the electrode 2592.

[0506] A pair of electrodes 2591 are provided with one electrode 2592 interposed therebetween. A pair of electrodes 2591 are electrically connected.

[0507] In addition, the multiple electrodes 2591 are arranged in a direction that is not necessarily perpendicular to one electrode 2592. The electrodes do not necessarily have to be disposed at an angle greater than 0 degrees and less than 90 degrees.

[0508] The wiring 2598 is electrically connected to the electrode 2591 or the electrode 2592. A part of the wiring 2598 functions as a terminal. The wiring 2598 is made of, for example, aluminum. Aluminum, gold, platinum, silver, nickel, titanium, tungsten, chromium, molybdenum, iron, Use of metal materials such as ballast, copper, or palladium, or alloy materials containing such metal materials. can be done.

[0509] An insulating layer is provided to cover the insulating layer 2593 and the wiring 2594, and the touch sensor 2595 may be protected.

[0510] The connection layer 2599 electrically connects the wiring 2598 and the FPC 2509(2). .

[0511] The connection layer 2599 is made of an anisotropic conductive film (ACF). conductive film) and anisotropic conductive paste (ACP) Conductive Paste) can be used.

[0512] <Touch panel explanation 2> Next, the touch panel 2000 will be described in detail with reference to FIG. This corresponds to a cross-sectional view taken along dashed line X5-X6 shown in 25(A).

[0513] The touch panel 2000 shown in FIG. 27 includes the display device 2501 described in FIG. 26(A), This configuration is formed by bonding the touch sensor 2595 described in FIG.

[0514] The touch panel 2000 shown in FIG. 27 is the same as that described in FIG. 26(A) and FIG. 26(C). In addition to this configuration, it has an adhesive layer 2597 and an anti-reflection layer 2567p.

[0515] The touch sensor 2595 is provided on the substrate 2510 side of the display device 2501 .

[0516] The adhesive layer 2597 is between the substrate 2510 and the substrate 2590 and is in contact with the display device 2501. Stick the Chisensor 2595 together.

[0517] In addition, it is preferable that the adhesive layer 2597 is transparent. , thermosetting resin, or ultraviolet curing resin can be used. For example, acrylic resin , urethane-based resin, epoxy-based resin, or siloxane-based resin can be used.

[0518] The anti-reflection layer 2567p is provided at a position overlapping the pixel. For example, a circular polarizing plate can be used.

[0519] The colored layer 2567R is located so as to overlap the light emitting element 2550R. The light-emitting element 2550R shown in FIG. 1 emits light toward the side where the transistor 2502t is provided. As a result, a part of the light emitted by the light emitting element 2550R passes through the colored layer 2567R, The light is emitted to the outside of light emitting module 2580R in the direction of the arrow shown in the figure.

[0520] <Explanation of how to drive the touch panel> Next, an example of a method for driving a touch panel will be described with reference to FIGS. 28(A) and 28(B). cormorant.

[0521] FIG. 28A is a block diagram showing the configuration of a mutual capacitance type touch sensor. In (A), a pulse voltage output circuit 2601 and a current detection circuit 2602 are shown. In FIG. 28(A), the electrodes 2621 to which the pulse voltage is applied are designated as X1-X6, and the change in current The electrodes 2622 for detecting the change are shown as Y1-Y6, each having six wires. FIG. 28(A) shows a capacitance 2 formed by overlapping an electrode 2621 and an electrode 2622. 603. The electrodes 2621 and 2622 have functions interchangeably. This is also fine.

[0522] The pulse voltage output circuit 2601 is a circuit for applying pulses to the wirings X1-X6 in sequence. When a pulse voltage is applied to the wiring of X1-X6, the voltage that forms the capacitance 2603 An electric field is generated between the electrodes 2621 and 2622. The electric field generated between the electrodes is blocked by By using the change in the mutual capacitance of the capacitance 2603, the proximity of the object to be detected or A contact can be detected.

[0523] The current detection circuit 2602 detects the change in mutual capacitance of the capacitor 2603 between the wirings Y1-Y6. This is a circuit to detect changes in current at the sensor. The wiring of Y1-Y6 detects the proximity of the object to be detected, Or, if there is no contact, the detected current value will not change, but the proximity of the object to be detected, or When the mutual capacitance decreases due to contact, a change in the current value is detected. The detection may be performed using an integrating circuit or the like.

[0524] Next, FIG. 28B shows an input of the mutual capacitance type touch sensor shown in FIG. The timing chart of the output waveform is shown in FIG. 28(B). In FIG. 28B, the sensor detects the object to be detected. The two cases shown are when detecting the object (touch) and when detecting the object (touch). For the wire 6, a waveform is shown in which the voltage value corresponds to the detected current value.

[0525] A pulse voltage is applied to the wires X1-X6 in sequence, and the The waveform in the Y6 wiring changes. When there is no proximity or contact of the object to be detected, X1-X6 The waveforms of Y1-Y6 change uniformly according to the change in the voltage of the wiring. Or, at the point of contact, the current value decreases, and the corresponding voltage waveform also changes. do.

[0526] In this way, by detecting the change in mutual capacitance, the proximity or contact of the object to be detected can be detected. It is possible.

[0527] <Sensor circuit description> In FIG. 28A, only a capacitor 2603 is provided at the intersection of the wiring as a touch sensor. The configuration of a passive matrix touch sensor has been shown, but it has a transistor and a capacitor. An active matrix type touch sensor may be used. An example of a sensor circuit included in the sensor is shown in FIG.

[0528] The sensor circuit shown in FIG. 29 includes a capacitor 2603, a transistor 2611, and a transistor 2612 and a transistor 2613.

[0529] A signal G2 is applied to the gate of the transistor 2613, and a voltage is applied to either the source or drain of the transistor 2613. A voltage VRES is applied to one electrode of a capacitor 2603 and a transistor 2611. The transistor 2611 has a source and a drain that are electrically connected to each other. One of the source and drain of the transistor 2612 is electrically connected to the other of the source and drain of the transistor 2612. A signal G1 is applied to the gate of the transistor 2612, and a signal S is applied to the source or The other electrode of the drain is electrically connected to the wiring ML. The other electrode of the capacitor 2603 is connected to a voltage VS S is given.

[0530] Next, the operation of the sensor circuit shown in FIG. 29 will be described. First, the signal G2 is When a potential is applied to turn on the transistor 2613, the gate of the transistor 2611 is turned on. A potential corresponding to the voltage VRES is applied to the node n to which the input is connected. When a potential that turns off the transistor 2613 is applied, the potential of the node n is Retained.

[0531] Next, the mutual capacitance of the capacitor 2603 changes due to the proximity or contact of a detection object such as a finger. Accordingly, the potential of the node n changes from VRES.

[0532] The read operation applies a potential to the signal G1 that turns on the transistor 2612. A current flows through the transistor 2611 in accordance with the potential of the node n, that is, a current flows through the wiring ML. By detecting this current, the proximity or contact of the object to be detected can be detected. This can be done.

[0533] The transistors 2611, 2612, and 2613 include It is preferable to use an oxide semiconductor layer as the semiconductor layer in which the channel region is formed. By applying such a transistor to the transistor 2613, the potential of the node n can be It is possible to hold the voltage for a long period of time, and the operation of re-supplying VRES to node n (restart) is performed. This can reduce the frequency of refresh operations.

[0534] The structure described in this embodiment may be used in appropriate combination with structures described in other embodiments. can be done.

[0535] (Embodiment 6) In this embodiment, a light-emitting device according to one embodiment of the present invention and a reflective liquid crystal element are included, and a transmissive A display device capable of performing display in both the reflective and reflective modes is shown in FIG. 30 to FIG. 33. The following explanation will be given using the following.

[0536] FIG. 30A is a bottom view illustrating a structure of a display device 300 according to one embodiment of the present invention. FIG. 30(B) is a bottom view for explaining a part of FIG. 30(A). Therefore, some of the components shown in FIG. 30(B) are omitted.

[0537] FIG. 31 is a cross-sectional view illustrating a structure of a display device 300 according to one embodiment of the present invention. , Section lines X1-X2, X3-X4, X5-X6, X7-X8, X9-X1 in Figure 30(A) 0, a cross-sectional view taken along X11-X12.

[0538] FIG. 32 illustrates a circuit of a pixel 302 included in a display device 300 of one embodiment of the present invention. be.

[0539] <Example of display device configuration> As shown in FIG. 30A, a display device 300 of one embodiment of the present invention includes a pixel portion 502 and a display The pixel unit 502 includes a driver circuit GD and a driver circuit SD arranged outside the pixel unit 502. 502 includes the pixel 302 .

[0540] The pixel 302 includes a liquid crystal element 350 and a light-emitting element 550. The pixel 302 also includes a transistor 585 and a transistor The casing has a stalk 586 (see FIG. 31).

[0541] The light emitting element 550 has a function of displaying in the same direction as the liquid crystal element 350. For example, the liquid crystal element 350 controls the intensity of reflection of external light to change the display direction as shown in FIG. 31. The direction in which the light emitting element 550 displays light is indicated by a solid arrow in FIG. Indicated by mark.

[0542] The liquid crystal element 350 includes a reflective film 351B having a function of reflecting incident light, and a reflecting layer 352B having a function of reflecting the light. and a liquid crystal layer 353 having a material that has a function of controlling the strength of the liquid crystal. The element 350 has a function of reflecting incident light and a function of controlling the intensity of the reflected light. do.

[0543] It is preferable to use a reflective liquid crystal element for the liquid crystal element 350. The element 350 includes an electrode 351 and an electrode 352 in addition to the liquid crystal layer 353. The liquid crystal layer 353 is made of a liquid crystal material. The electrode 352 has a liquid crystal material. An electric field is applied between the electrode 351 and the electrode 352 to control the alignment of the liquid crystal material. The liquid crystal layer 353 is arranged so that the light entering the liquid crystal element 350 is reflected by the reflective film 35 It has the function of controlling the intensity of light reflected by 1B.

[0544] The electrode 351 is electrically connected to the transistor 581. The electrode 351 is also The conductive film 351A and the conductive film 351C are arranged to sandwich the conductive film 351B. It is preferable that the reflective film 351B is sandwiched between the conductive film 351A and the conductive film 351C. It is possible to suppress the element contained in the film 351B from diffusing into other layers. This can prevent the reflection film 351B from being contaminated by impurities entering from the outside.

[0545] In addition, the conductive film 351A and the conductive film 351C preferably have a function of transmitting light. Since the conductive film 351A has a function of transmitting light, light entering the liquid crystal element 350 from the outside can be prevented from entering the liquid crystal element 350. The light incident on the conductive film 351C can be efficiently reflected by the conductive film 351B. By having the function of transmitting light, the light emitted by the light emitting element 550 can be efficiently transmitted as described later. It can be easily taken out to the outside.

[0546] The display device 300 also includes an alignment film 331 and an alignment film 332. The alignment film 332 is , and the alignment film 331 are disposed so as to sandwich a liquid crystal layer 353 therebetween.

[0547] In addition, the display device 300 includes a colored layer 375 and a light-shielding layer 373 in an area overlapping the pixel 302. , an insulating film 371, a functional film 370D, and a functional film 370P.

[0548] The colored layer 375 has an area overlapping with the liquid crystal element 350. The colored layer 375 is provided to allow the liquid crystal element to be exposed from the outside. The light incident on the element 350 passes through the colored layer 375 and enters the reflective film 351B. The light reflected by the liquid crystal element 350 is extracted to the outside via the colored layer 375. The light that is incident on the substrate and reflected can be extracted to the outside in a specified color.

[0549] The insulating film 371 is provided between the colored layer 375 and the liquid crystal layer 353, or between the light blocking layer 373 and the liquid crystal layer 353. 53. This prevents the liquid crystal layer 3 from being blocked by the light blocking layer 373 or the colored layer 375. In addition, the unevenness based on the thickness of the colored layer 375 can be suppressed. An insulating film 371 may be provided to flatten the surface.

[0550] The functional film 370D and the functional film 370P have an area overlapping with the liquid crystal element 350. The functional film 370D is disposed between the liquid crystal element 350 and the substrate 370. The liquid crystal element 350 and the light emitting element 550 are provided with a function film 370D and a function film 370P. A film having a function of protecting the surface of the display device 300, etc., may be used. It is possible to use only one of the functional films 370D and 370P.

[0551] The display device 300 also includes a substrate 370, a substrate 570, and a functional layer 520.

[0552] The substrate 370 has an area overlapping with the substrate 570. The functional layer 520 is It is disposed between the substrate 370 .

[0553] The functional layer 520 includes a transistor included in the pixel 302, a light-emitting element 550, and an insulating film 52...

Claims

1. The present invention has a light-emitting element, a color conversion element using quantum dots, and a transistor including an oxide semiconductor, the light-emitting element has a first electrode, a second electrode, a first light-emitting layer provided between the first electrode and the second electrode, and a second light-emitting layer provided between the first light-emitting layer and the second electrode; an emission peak wavelength of the light-emitting material contained in the first light-emitting layer is shorter than an emission peak wavelength of the light-emitting material contained in the second light-emitting layer; the second light-emitting layer includes a first organic compound and a second organic compound; a HOMO level of the first organic compound is higher than a HOMO level of the second organic compound; a LUMO level of the first organic compound is higher than a HOMO level of the second organic compound; the light-emitting element is connected to the transistor including the oxide semiconductor; A light emitting device in which light from the light emitting element is converted into light with a longer wavelength by the color conversion element and emitted.

2. The present invention has a light-emitting element, a color conversion element using quantum dots, and a transistor including an oxide semiconductor, the light-emitting element has a first electrode, a second electrode, a first light-emitting layer provided between the first electrode and the second electrode, and a second light-emitting layer provided between the first light-emitting layer and the second electrode; an emission peak wavelength of the light-emitting material contained in the first light-emitting layer is shorter than an emission peak wavelength of the light-emitting material contained in the second light-emitting layer; the second light-emitting layer includes a first organic compound and a second organic compound; an energy difference between a HOMO level of the first organic compound and a HOMO level of the second organic compound is 0.05 eV or more; an energy difference between a LUMO level of the first organic compound and a LUMO level of the second organic compound is 0.2 eV or more; the light-emitting element is connected to the transistor including the oxide semiconductor; A light emitting device in which light from the light emitting element is converted into light with a longer wavelength by the color conversion element and emitted.

3. In claim 1 or 2, the first light-emitting layer has a fourth organic compound; A light emitting device, wherein the T1 level of the fourth organic compound is lower than the T1 level of the first organic compound and the T1 level of the second organic compound.

4. In any one of claims 1 to 3, a first conductive film having a metal oxide, a second conductive film having Ag on the first conductive film, and a third conductive film having a metal oxide on the second conductive film;

Images