Method for manufacturing a display device, display device, display module, and electronic device.

Abstract

Provided is a high-definition or high-resolution display device. The display device is fabricated by: forming a first pixel electrode and a second pixel electrode; forming a first layer on the first pixel electrode and the second pixel electrode; forming a first sacrificial layer on the first layer; processing the first layer and the first sacrificial layer to expose at least a portion of the second pixel electrode; forming a second layer on the first pixel electrode and the second pixel electrode; forming a second sacrificial layer on the second layer; processing the second layer and the second sacrificial layer to expose at least a portion of the first sacrificial layer; removing the first sacrificial layer and the second sacrificial layer; forming a third layer on the first pixel electrode and the second pixel electrode; forming a counter electrode on the third layer; and processing the third layer and the counter electrode to remove at least a portion of each of the third layer and the counter electrode included in an area between the first pixel electrode and the second pixel electrode in a top view.

Description

[Technical Field]

[0001] One aspect of the present invention relates to a method for manufacturing a display device. Another aspect of the present invention relates to a display device, a display module, and electronic equipment.

[0002] It should be noted that one aspect of the present invention is not limited to the above-mentioned technical field. Examples of technical fields of one aspect of the present invention include semiconductor devices, display devices, light-emitting devices, energy storage devices, memory devices, electronic devices, lighting devices, input devices (e.g., touch sensors), input / output devices (e.g., touch panels), methods for driving them, or methods for manufacturing them. [Background technology]

[0003] In recent years, display devices have been expected to have applications in a variety of uses. For example, large-scale display devices are used in home television systems (also called televisions or television receivers), digital signage, and PID (Public Information Display). Furthermore, development is progressing on mobile information terminals such as smartphones and tablet devices equipped with touch panels.

[0004] Furthermore, there is a demand for higher resolution display devices. Devices requiring high-resolution displays, such as those for virtual reality (VR), augmented reality (AR), substitutional reality (SR), and mixed reality (MR), are being actively developed.

[0005] As a display device, for example, a light-emitting device (also called a light-emitting element) has been developed. Light-emitting devices that utilize the electroluminescence (EL) phenomenon (also called EL devices or EL elements) have features such as being easy to make thin and light, being able to respond quickly to input signals, and being able to be driven using a DC constant voltage power supply, and are being applied to display devices.

[0006] Patent Document 1 discloses a display device for VR using an organic EL device (also called an organic EL element). [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] International Publication No. 2018 / 087625 [Overview of the project] [Problems that the invention aims to solve]

[0008] When manufacturing a display device having multiple organic EL devices, each with a different light-emitting layer color, it is necessary to form each light-emitting layer with a different color in an island-like structure.

[0009] For example, island-shaped light-emitting layers can be formed using a vacuum deposition method with a metal mask (also called a shadow mask). However, during deposition, the outline of the layer may become blurred, and the thickness at the edges may become thinner. In other words, the thickness of the island-shaped light-emitting layer may vary depending on the location. Furthermore, when manufacturing large, high-resolution, or high-definition display devices, there are concerns that the low dimensional accuracy of the metal mask and deformation due to heat, etc., may lead to a low manufacturing yield.

[0010] In addition, when manufacturing a display device using a vacuum evaporation method with a metal mask, there is a problem that a plurality of production lines are required for the manufacturing equipment. For example, since it is necessary to clean the metal mask regularly, at least two or more production lines of manufacturing equipment need to be prepared, and it is necessary to use the other production line for manufacturing while one production line is under maintenance. Considering mass production, a plurality of production lines are required for the manufacturing equipment. Therefore, there is a problem that the initial investment for introducing the manufacturing equipment becomes extremely large.

[0011] One aspect of the present invention is to provide a method for manufacturing a high-definition display device as one of the problems. One aspect of the present invention is to provide a method for manufacturing a high-resolution display device as one of the problems. One aspect of the present invention is to provide a method for manufacturing a large-sized display device as one of the problems. One aspect of the present invention is to provide a method for manufacturing a highly reliable display device as one of the problems. One aspect of the present invention is to provide a method for manufacturing a display device with a high yield as one of the problems.

[0012] One aspect of the present invention is to provide a high-definition display device as one of the problems. One aspect of the present invention is to provide a high-resolution display device as one of the problems. One aspect of the present invention is to provide a large-sized display device as one of the problems. One aspect of the present invention is to provide a highly reliable display device as one of the problems.

[0013] Note that the description of these problems does not prevent the existence of other problems. One aspect of the present invention does not necessarily need to solve all of these problems. It is possible to extract other problems from the description of the specification, drawings, and claims.

Means for Solving the Problems

[0014] One aspect of the present invention is a method for manufacturing a display device, comprising: forming a first pixel electrode and a second pixel electrode; forming a first layer on the first pixel electrode and the second pixel electrode; forming a first sacrificial layer on the first layer; processing the first layer and the first sacrificial layer to expose at least a portion of the second pixel electrode; forming a second layer on the first pixel electrode and the second pixel electrode; forming a second sacrificial layer on the second layer; processing the second layer and the second sacrificial layer to expose at least a portion of the first sacrificial layer; removing the first sacrificial layer and the second sacrificial layer; forming a third layer on the first pixel electrode and the second pixel electrode; forming a counter electrode on the third layer; and processing the third layer and the counter electrode to remove at least a portion of the third layer and the counter electrode, which are included in the region between the first pixel electrode and the second pixel electrode in a top view.

[0015] It is preferable to form a protective layer on the counter electrode after processing the third layer and the counter electrode. As the protective layer, a first protective layer may be formed by the first film formation method and a second protective layer may be formed by the second film formation method. The first film formation method may be a film formation method that forms a film with higher coverage than the second film formation method.

[0016] Before forming the first layer, an insulating layer may be formed to cover the ends of the first and second pixel electrodes. In the process of processing the third layer and the counter electrodes, at least a portion of the insulating layer may be exposed.

[0017] It is preferable to form a first resist mask on the first sacrificial layer that overlaps with the first pixel electrode, and to use the first resist mask when processing the first layer and the first sacrificial layer. It is preferable to form a second resist mask on the second sacrificial layer that overlaps with the second pixel electrode, and to use the second resist mask when processing the second layer and the second sacrificial layer.

[0018] A third resist mask may be formed on the counter electrode, having an opening in the region between the first pixel electrode and the second pixel electrode in a top view. Alternatively, a third resist mask may be formed on the counter electrode, having a first portion overlapping the first pixel electrode and a second portion overlapping the second pixel electrode, separated from each other. It is preferable to use the third resist mask when processing the third layer and the counter electrode.

[0019] Alternatively, in one aspect of the present invention, a plurality of first pixel electrodes arranged in a first direction and a plurality of second pixel electrodes arranged in a first direction are formed in a second direction, a first layer is formed on the plurality of first pixel electrodes and the plurality of second pixel electrodes, a first sacrificial layer is formed on the first layer, the first layer and the first sacrificial layer are processed to expose at least a portion of each of the plurality of second pixel electrodes, a second layer is formed on the plurality of first pixel electrodes and the plurality of second pixel electrodes, a second sacrificial layer is formed on the second layer, the second layer and the second sacrificial layer are processed to expose at least a portion of the first sacrificial layer, and the first sacrificial layer This is a method for manufacturing a display device, comprising: removing the first and second sacrificial layers; forming a third layer on a plurality of first pixel electrodes and a plurality of second pixel electrodes; forming counter electrodes on the third layer; processing the third layer and the counter electrodes to remove at least a portion of each of the third layer and the counter electrodes included in the region between the first and second pixel electrodes in a top view; forming a protective layer on the counter electrodes; processing the protective layer to expose at least a portion of the counter electrodes included in the region between the plurality of first pixel electrodes and a plurality of second pixel electrodes in a top view; and forming a conductive layer on the counter electrodes and the protective layer.

[0020] As a protective layer, a first protective layer may be formed by a first film formation method, and a second protective layer may be formed by a second film formation method. The first film formation method may be a film formation method that forms a film with higher coverage than the second film formation method.

[0021] Before forming the first layer, an insulating layer may be formed to cover the ends of the multiple first pixel electrodes and the ends of the multiple second pixel electrodes. In the process of processing the third layer and the counter electrodes, at least a portion of the insulating layer may be exposed.

[0022] It is preferable to form a first resist mask on the first sacrificial layer that overlaps with the first pixel electrode, and to use the first resist mask when processing the first layer and the first sacrificial layer. It is preferable to form a second resist mask on the second sacrificial layer that overlaps with the second pixel electrode, and to use the second resist mask when processing the second layer and the second sacrificial layer.

[0023] A third resist mask may be formed on the counter electrode, having an opening in the region between the first pixel electrode and the second pixel electrode in a top view. Alternatively, a third resist mask may be formed on the counter electrode, having a first portion overlapping with a plurality of first pixel electrodes and a second portion overlapping with a plurality of second pixel electrodes separated from each other. It is preferable to use the third resist mask when processing the third layer and the counter electrode.

[0024] A fourth resist mask may be formed on the protective layer, having openings in the regions between the plurality of first pixel electrodes and the regions between the plurality of second pixel electrodes when viewed from above. Alternatively, a fourth resist mask may be formed on the protective layer, having a third portion that overlaps with at least one of the plurality of first pixel electrodes and at least one of the plurality of second pixel electrodes, and a fourth portion that overlaps with at least one other of the plurality of first pixel electrodes and at least one other of the plurality of second pixel electrodes, separated from each other. It is preferable to use the fourth resist mask when processing the protective layer.

[0025] One aspect of the present invention is a display device having a plurality of first light-emitting devices and a plurality of second light-emitting devices. The first light-emitting device has a first pixel electrode, a first layer on the first pixel electrode, a third layer on the first layer, and a counter electrode on the third layer. The second light-emitting device has a second pixel electrode, a second layer on the second pixel electrode, a third layer on the second layer, and a counter electrode on the third layer. The first light-emitting device and the second light-emitting device have the function of emitting light of different colors from each other. In a top view, the region between the first pixel electrode and the second pixel electrode has a portion where the third layer and counter electrode are not provided. The third layer and counter electrode are provided across the plurality of first light-emitting devices. The third layer and counter electrode are provided across the plurality of second light-emitting devices.

[0026] The above-described display device preferably has a protective layer on the counter electrode. There may also be a gap between the first light-emitting device and the second light-emitting device surrounded by the protective layer.

[0027] Alternatively, the display device preferably has a first protective layer on the counter electrode and a second protective layer on the first protective layer. There may be a gap between the first light-emitting device and the second light-emitting device, surrounded by the first protective layer and the second protective layer.

[0028] Alternatively, one aspect of the present invention is a display device comprising a plurality of first light-emitting devices and a plurality of second light-emitting devices, a protective layer on the plurality of first light-emitting devices and on the plurality of second light-emitting devices, and a conductive layer on the protective layer. The first light-emitting device comprises a first pixel electrode, a first layer on the first pixel electrode, a third layer on the first layer, and a counter electrode on the third layer. The second light-emitting device comprises a second pixel electrode, a second layer on the second pixel electrode, a third layer on the second layer, and a counter electrode on the third layer, and the first light-emitting device and the second light-emitting device have the function of emitting light of different colors from each other. In a top view, the region between the first pixel electrode and the second pixel electrode has a first portion where the third layer and the counter electrode are not provided. The third layer and the counter electrode are provided across the plurality of first light-emitting devices. The third layer and counter electrodes are provided across a plurality of second light-emitting devices. In a top view, the region between the two first pixel electrodes and the region between the two second pixel electrodes each have a second portion without a protective layer. In the second portion, the counter electrodes and the conductive layer are electrically connected.

[0029] The above-described display device may have a gap surrounded by a protective layer between the first light-emitting device and the second light-emitting device.

[0030] The protective layer preferably includes a first protective layer on the counter electrode and a second protective layer on the first protective layer. There may be a gap between the first light-emitting device and the second light-emitting device, surrounded by the first protective layer and the second protective layer.

[0031] One aspect of the present invention is a display module having a display device with any of the above configurations, to which a connector such as a Flexible Printed Circuit (FPC) or TCP (Tape Carrier Package) is attached, or a display module on which an integrated circuit (IC) is mounted by a COG (Chip On Glass) method or a COF (Chip On Film) method, etc.

[0032] One aspect of the present invention is an electronic device having the above-mentioned display module and at least one of a housing, a battery, a camera, a speaker, and a microphone. [Effects of the Invention]

[0033] According to one aspect of the present invention, a method for manufacturing a high-definition display device can be provided. According to one aspect of the present invention, a method for manufacturing a high-resolution display device can be provided. According to one aspect of the present invention, a method for manufacturing a large-scale display device can be provided. According to one aspect of the present invention, a method for manufacturing a highly reliable display device can be provided. According to one aspect of the present invention, a method for manufacturing a display device with a high yield can be provided.

[0034] According to one aspect of the present invention, a high-definition display device can be provided. According to one aspect of the present invention, a high-resolution display device can be provided. According to one aspect of the present invention, a large-screen display device can be provided. According to one aspect of the present invention, a highly reliable display device can be provided.

[0035] Furthermore, the description of these effects does not preclude the existence of other effects. One aspect of the present invention does not necessarily have to possess all of these effects. Other effects can be extracted from the description, drawings, and claims. [Brief explanation of the drawing]

[0036] Figure 1A is a top view showing an example of a display device. Figure 1B is a cross-sectional view showing an example of a display device. Figures 2A to 2F are top views showing an example of a display device. Figures 3A to 3C are cross-sectional views showing an example of a method for manufacturing a display device. Figures 4A to 4C are cross-sectional views showing an example of a method for manufacturing a display device. Figures 5A to 5C are cross-sectional views showing an example of a method for manufacturing a display device. Figures 6A to 6C are cross-sectional views showing an example of a method for manufacturing a display device. Figures 7A to 7C are cross-sectional views showing an example of a method for manufacturing a display device. Figures 8A to 8C are cross-sectional views showing an example of a method for manufacturing a display device. Figures 9A and 9B are cross-sectional views showing an example of a display device. Figure 10 is a perspective view showing an example of a display device. Figure 11A is a cross-sectional view showing an example of a display device. Figures 11B and 11C are cross-sectional views showing an example of a transistor. Figures 12A and 12B are perspective views showing an example of a display module. Figure 13 is a cross-sectional view showing an example of a display device. Figure 14 is a cross-sectional view showing an example of a display device. Figure 15 is a cross-sectional view showing an example of a display device. Figures 16A to 16D show examples of the configuration of a light-emitting device. Figures 17A and 17B show examples of electronic devices. Figures 18A and 18B show examples of electronic devices. Figures 19A and 19B show examples of electronic devices. Figures 20A to 20D show examples of electronic devices. Figures 21A to 21F show examples of electronic devices. [Modes for carrying out the invention]

[0037] Embodiments will be described in detail with reference to the drawings. However, it will be readily apparent to those skilled in the art that the present invention is not limited to the following description, and that its form and details can be modified in various ways without departing from the spirit and scope of the present invention. Accordingly, the present invention shall not be construed as being limited to the descriptions of the embodiments shown below.

[0038] In the invention described below, the same reference numerals are used in common across different drawings for identical parts or parts having similar functions, and repeated explanations are omitted. Furthermore, when referring to similar functions, the same hatching pattern may be used, and reference numerals may not be assigned.

[0039] Furthermore, the position, size, and scope of each component shown in the drawings may not represent the actual position, size, and scope for the sake of ease of understanding. Therefore, the disclosed invention is not necessarily limited to the position, size, and scope disclosed in the drawings.

[0040] It should be noted that the terms "film" and "layer" can be interchanged depending on the context or situation. For example, the term "conductive layer" can be changed to "conductive film." Or, for example, the term "insulating film" can be changed to "insulating layer."

[0041] In this specification, devices fabricated using a metal mask or an FMM (Fine Metal Mask, a high-resolution metal mask) may be referred to as MM (Metal Mask) structured devices. Furthermore, in this specification, devices fabricated without using a metal mask or an FMM may be referred to as MML (Metal Maskless) structured devices.

[0042] (Embodiment 1) In this embodiment, a display device according to one aspect of the present invention and a method for manufacturing the same will be explained with reference to Figures 1 to 9.

[0043] In a method for manufacturing a display device according to one aspect of the present invention, island-shaped pixel electrodes (also called lower electrodes) are formed, and a first layer (which can be called an EL layer or a part of an EL layer) containing a light-emitting layer that emits light of a first color is formed on one surface, and then a first sacrificial layer is formed on the first layer. Then, a first resist mask is formed on the first sacrificial layer, and the first layer and the first sacrificial layer are processed using the first resist mask to form an island-shaped first layer. Subsequently, a second layer (which can be called an EL layer or a part of an EL layer) containing a light-emitting layer that emits light of a second color is formed in an island shape using the second sacrificial layer and the second resist mask, similar to the first layer.

[0044] Thus, in the method for manufacturing a display device according to one aspect of the present invention, the island-shaped EL layer is formed not by using a fine metal mask, but by processing after the EL layer has been deposited on one surface, so that the island-shaped EL layer can be formed with a uniform thickness. Furthermore, by providing a sacrificial layer (which may also be called a mask layer) on the EL layer, the damage the EL layer receives during the manufacturing process of the display device can be reduced, and the reliability of the light-emitting device can be improved.

[0045] Here, the first layer and the second layer each include at least an emissive layer, and preferably consist of multiple layers. Specifically, it is preferable to have one or more layers on the emissive layer. By having other layers between the emissive layer and the sacrificial layer, it is possible to suppress the exposure of the emissive layer to the outermost surface during the manufacturing process of the display device, thereby reducing damage to the emissive layer. This can improve the reliability of the light-emitting device.

[0046] Furthermore, in light-emitting devices that emit light of different colors, it is not necessary to fabricate all the layers constituting the EL layer separately; some layers can be deposited in the same process. In a method for manufacturing a display device according to one aspect of the present invention, some of the layers constituting the EL layer are formed in island-like structures for each color, then the sacrificial layer is removed, and the remaining layers constituting the EL layer and the counter electrode (also called the upper electrode) are formed in common for each color of light-emitting device. Then, a third resist mask is formed on the counter electrode, and the EL layer and the counter electrode included in the region between the light-emitting device emitting light of the first color and the light-emitting device emitting light of the second color are removed using the third resist mask.

[0047] For example, when manufacturing a high-definition or high-resolution display device, the distance between light-emitting devices is often extremely short (or, more accurately, the spacing between light-emitting devices is narrow). As a result, the layers of adjacent light-emitting devices may overlap or come into contact with each other. Therefore, in a method for manufacturing a display device according to one aspect of the present invention, a third resist mask is used to process not only the counter electrode and the layer commonly formed for each color of light-emitting device (corresponding to the remaining layers that make up the EL layer), but also the first and second layers, which are formed in island shapes beforehand (each corresponding to a part of the layers that make up the EL layer). This suppresses overlapping or contact between the first and second layers, and electrically isolates adjacent light-emitting devices that emit light of different colors. As a result, it is possible to suppress current leakage to adjacent light-emitting devices and the emission of light from devices other than the desired one (also known as crosstalk).

[0048] Processing using a third resist mask creates an opening in the counter electrode, or divides the counter electrode into strips to form multiple patterns. Here, a voltage drop due to the resistance of the counter electrode may occur, resulting in an uneven potential distribution within the display surface of the counter electrode. This can cause variations in the brightness of the light-emitting devices and a decrease in the display quality of the display device. Therefore, in a method for manufacturing a display device according to one aspect of the present invention, a conductive layer is provided that is electrically connected to the counter electrode. Specifically, a protective layer is formed on the counter electrode, a fourth resist mask is formed on the protective layer, and the protective layer is processed using the fourth resist mask to expose a portion of the counter electrode. The counter electrode is preferably exposed in the region between two light-emitting devices emitting light of a first color, and in the region between two light-emitting devices emitting light of a second color. Then, a conductive layer is formed on the counter electrode and on the protective layer. The conductive layer is provided over a larger area than the counter electrode and functions as auxiliary wiring. By providing the conductive layer over the entire surface, voltage drops due to the resistance of the counter electrode can be suppressed, brightness unevenness of the display device can be reduced, and high display quality can be achieved. Furthermore, if a conductive layer is provided on the side from which light is extracted, it is preferable that the conductive layer be formed using a material that transmits visible light.

[0049] [Example of a display device configuration] Figures 1A and 1B show a display device according to one embodiment of the present invention.

[0050] Figure 1A shows a top view of the display device 100. The display device 100 has a display unit in which a plurality of pixels 110 are arranged in a matrix, and a connection unit 140 outside the display unit. One pixel 110 is composed of three sub-pixels, 110a, 110b, and 110c. The connection unit 140 can also be called the cathode contact unit.

[0051] The top surface shape of the subpixel shown in Figure 1A corresponds to the top surface shape of the light-emitting region.

[0052] Furthermore, the circuit layout constituting the subpixel is not limited to the subpixel range shown in Figure 1A, but may be located outside of it. For example, the transistors in subpixel 110a may be located within the range of subpixel 110b shown in Figure 1A, or some or all of them may be located outside the range of subpixel 110a.

[0053] In Figure 1A, the aperture ratios (size, also known as the size of the light-emitting area) of the sub-pixels 110a, 110b, and 110c are shown to be equal or approximately equal, but one aspect of the present invention is not limited thereto. The aperture ratios of the sub-pixels 110a, 110b, and 110c can be determined as appropriate. The aperture ratios of the sub-pixels 110a, 110b, and 110c may be different, or two or more may be equal or approximately equal.

[0054] Figure 1A shows an example where subpixels of different colors are arranged in the X direction, and subpixels of the same color are arranged in the Y direction. Alternatively, subpixels of different colors may be arranged in the Y direction, and subpixels of the same color may be arranged in the X direction.

[0055] Figure 1A shows an example where the connection portion 140 is located below the display portion in a top view, but it is not particularly limited. The connection portion 140 only needs to be provided at least one location on the top, right, left, or bottom of the display portion in a top view, and may be provided so as to surround all four sides of the display portion.

[0056] Figure 1B shows a cross-sectional view between the dashed line X1 and X2 in Figure 1A.

[0057] As shown in Figure 1B, the display device 100 has light-emitting devices 130a, 130b, and 130c provided on a layer 101 containing transistors, and protective layers 131 and 132 are provided to cover these light-emitting devices. A substrate 120 is bonded to the protective layer 132 by a resin layer 119.

[0058] A display device according to one aspect of the present invention may be a top-emission type that emits light in the direction opposite to the substrate on which the light-emitting device is formed, a bottom-emission type that emits light toward the substrate on which the light-emitting device is formed, or a dual-emission type that emits light on both sides.

[0059] For example, the layer 101 containing transistors can be a laminated structure in which multiple transistors are provided on a substrate and an insulating layer is provided to cover these transistors. Examples of the configuration of the layer 101 containing transistors will be described later in Embodiments 2 and 3.

[0060] Each of the light-emitting devices 130a, 130b, and 130c emits light of a different color. Preferably, the light-emitting devices 130a, 130b, and 130c are a combination that emits, for example, red (R), green (G), and blue (B) light.

[0061] The light-emitting device has an EL layer between a pair of electrodes. In this specification, one of the pair of electrodes may be referred to as the pixel electrode and the other as the counter electrode.

[0062] The light-emitting device 130a includes a pixel electrode 111a on a layer 101 containing a transistor, a first layer 113a on the pixel electrode 111a, a fourth layer 114a on the first layer 113a, and a counter electrode 115a on the fourth layer 114a. In the light-emitting device 130a, the first layer 113a and the fourth layer 114a can be collectively referred to as the EL layer.

[0063] The light-emitting device 130b includes a pixel electrode 111b on a layer 101 containing a transistor, a second layer 113b on the pixel electrode 111b, a fourth layer 114b on the second layer 113b, and a counter electrode 115b on the fourth layer 114b. In the light-emitting device 130b, the second layer 113b and the fourth layer 114b can be collectively referred to as the EL layer.

[0064] The light-emitting device 130c includes a pixel electrode 111c on a layer 101 containing a transistor, a third layer 113c on the pixel electrode 111c, a fourth layer 114c on the third layer 113c, and a counter electrode 115c on the fourth layer 114c. In the light-emitting device 130c, the third layer 113c and the fourth layer 114c can be collectively referred to as the EL layer.

[0065] In this embodiment, each color light-emitting device has a different reference numeral for its fourth layer, but the fourth layer of each color light-emitting device may be the same film. In other words, it can be described using the same reference numeral. Specifically, the fourth layer may be provided in an island-like (or strip-like) manner for each color, or it may be provided across multiple sub-pixels of multiple colors, covering the entire display unit.

[0066] Similarly, in this embodiment, each color light-emitting device has a counter electrode that is assigned a different reference numeral, but the counter electrodes of each color light-emitting device may be made of the same film. In other words, it is possible to describe them using the same reference numeral. Specifically, the counter electrodes may be provided in island-like (or strip-like) arrangements for each color, or they may be provided across multiple subpixels of different colors, covering the entire display area.

[0067] The counter electrodes of each color light-emitting device are electrically connected to the conductive layer provided in the connection section 140. As a result, the same potential is supplied to the counter electrodes of each color light-emitting device.

[0068] Of the pixel electrodes and counter electrodes, the electrode that extracts light preferably uses a conductive film that transmits visible light. Furthermore, it is preferable to use a conductive film that reflects visible light on the electrode that does not extract light.

[0069] As materials for forming the pair of electrodes (pixel electrode and counter electrode) of a light-emitting device, metals, alloys, electrically conductive compounds, and mixtures thereof can be used as appropriate. Specifically, examples include indium tin oxide (In-Sn oxide, also called ITO), In-Si-Sn oxide (also called ITSO), indium zinc oxide (In-Zn oxide), In-W-Zn oxide, aluminum-containing alloys such as aluminum, nickel, and lanthanum alloys (Al-Ni-La), and silver, palladium, and copper alloys (Ag-Pd-Cu, also written as APC). In addition, metals such as aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), neodymium (Nd), and alloys containing these in appropriate combinations can also be used. Furthermore, elements belonging to Group 1 or Group 2 of the periodic table not exemplified above (e.g., lithium (Li), cesium (Cs), calcium (Ca), strontium (Sr)), rare earth metals such as europium (Eu), ytterbium (Yb), and alloys containing these in appropriate combinations, graphene, etc., can also be used.

[0070] It is preferable that the light-emitting device has a microcavity structure. Therefore, it is preferable that one of the pair of electrodes in the light-emitting device has an electrode that is transparent to and reflective to visible light (a semi-transmissive / semi-reflective electrode), and the other has an electrode that is reflective to visible light (a reflective electrode). By having a microcavity structure in the light-emitting device, the light emitted from the light-emitting layer can be resonated between the two electrodes, thereby strengthening the light emitted from the light-emitting device.

[0071] Furthermore, semi-transmissive / semi-reflective electrodes can have a laminated structure consisting of a reflective electrode and an electrode that transmits visible light (also called a transparent electrode).

[0072] The light transmittance of the transparent electrode shall be 40% or more. For example, it is preferable to use an electrode in the light-emitting device that has a transmittance of 40% or more for visible light (light with a wavelength of 400 nm or more and less than 750 nm). The visible light reflectance of the semi-transparent / semi-reflective electrode shall be 10% or more and 95% or less, preferably 30% or more and 80% or less. The visible light reflectance of the reflective electrode shall be 40% or more and 100% or less, preferably 70% or more and 100% or less. The resistivity of these electrodes shall be 1 × 10⁻⁶ -2 A value of Ωcm or less is preferable.

[0073] The first layer 113a, the second layer 113b, and the third layer 113c each have an emissive layer. Preferably, the first layer 113a, the second layer 113b, and the third layer 113c each have an emissive layer that emits light of a different color.

[0074] The luminescent layer is a layer containing a luminescent material. The luminescent layer may contain one or more types of luminescent materials. Suitable luminescent materials include those exhibiting colors such as blue, purple, blue-violet, green, yellow-green, yellow, orange, and red. Furthermore, materials emitting near-infrared light may also be used as luminescent materials.

[0075] Examples of luminescent materials include fluorescent materials, phosphorescent materials, thermally activated delayed fluorescence (TADF) materials, and quantum dot materials.

[0076] Examples of fluorescent materials include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives.

[0077] Examples of phosphorescent materials include organometallic complexes (especially iridium complexes) having a 4H-triazole skeleton, 1H-triazole skeleton, imidazole skeleton, pyrimidine skeleton, pyrazine skeleton, or pyridine skeleton; organometallic complexes (especially iridium complexes) using phenylpyridine derivatives having electron-withdrawing groups as ligands; platinum complexes; and rare earth metal complexes.

[0078] The light-emitting layer may contain one or more types of organic compounds (host material, assist material, etc.) in addition to the light-emitting substance (guest material). One or more of these organic compounds may be hole-transporting materials and / or electron-transporting materials. Alternatively, one or more of these organic compounds may be bipolar materials or TADF materials.

[0079] The light-emitting layer preferably comprises, for example, a phosphorescent material and a combination of a hole-transporting material and an electron-transporting material that readily forms an excitation complex. This configuration allows for efficient emission using ExTET (Exciplex-Triplet Energy Transfer), which is energy transfer from the excitation complex to the light-emitting substance (phosphorescent material). By selecting a combination that forms an excitation complex that exhibits emission overlapping with the wavelength of the lowest-energy absorption band of the light-emitting substance, energy transfer becomes smoother, and light emission can be obtained efficiently. This configuration simultaneously achieves high efficiency, low-voltage operation, and a long lifespan for the light-emitting device.

[0080] The first layer 113a, the second layer 113b, and the third layer 113c may further include layers other than the light-emitting layer, such as a material with high hole injection properties, a material with high hole transport properties, a hole blocking material, a material with high electron transport properties, a material with high electron injection properties, an electron blocking material, or a bipolar material (a material with high electron transport and hole transport properties).

[0081] The light-emitting device may use either low-molecular-weight compounds or high-molecular-weight compounds, and may also contain inorganic compounds. The layers constituting the light-emitting device can be formed by methods such as vapor deposition (including vacuum deposition), transfer, printing, inkjet, and coating.

[0082] For example, the first layer 113a, the second layer 113b, and the third layer 113c may each have one or more of the following: a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer, an electron transport layer, and an electron injection layer.

[0083] The fourth layers 114a, 114b, and 114c may have one or more of the following: a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer, an electron transport layer, and an electron injection layer. For example, when the pixel electrodes 111a, 111b, and 111c function as anodes and the counter electrodes 115a, 115b, and 115c function as cathodes, it is preferable that the fourth layers 114a, 114b, and 114c have electron injection layers.

[0084] The hole injection layer is a layer that injects holes from the anode into the hole transport layer, and is a layer containing a material with high hole injection capabilities. Examples of materials with high hole injection capabilities include aromatic amine compounds and composite materials containing hole transport materials and acceptor materials (electron-accepting materials).

[0085] The hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light-emitting layer. The hole transport layer is a layer containing a hole-transporting material. The hole-transporting material is 1 × 10⁻¹⁶ -6 cm 2 Materials having a hole mobility of / Vs or higher are preferred. However, other materials can also be used as long as they have higher hole transport capabilities than electron transport. Preferred hole transport materials include π-electron-rich heteroaromatic compounds (e.g., carbazole derivatives, thiophene derivatives, furan derivatives, etc.) and aromatic amines (compounds having an aromatic amine skeleton), which are materials with high hole transport capabilities.

[0086] The electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light-emitting layer. The electron transport layer is a layer containing an electron-transporting material. The electron-transporting material is 1 × 10⁻¹⁶ -6 cm 2Materials having an electron mobility of 1 / Vs or higher are preferred. However, other materials can also be used as long as they have higher electron transport capabilities than holes. Examples of electron-transporting materials include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, metal complexes having a thiazole skeleton, as well as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives having a quinoline ligand, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and other π-electron-deficient heteroaromatic compounds containing nitrogen-containing heteroaromatic compounds, which are materials with high electron transport capabilities.

[0087] The electron injection layer is a layer that injects electrons from the cathode to the electron transport layer, and is a layer containing a material with high electron injection capabilities. Alkali metals, alkaline earth metals, or compounds thereof can be used as materials with high electron injection capabilities. Composite materials containing both electron transport materials and donor materials (electron-donating materials) can also be used as materials with high electron injection capabilities.

[0088] Examples of electron injection layers include lithium, cesium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), 8-(quinolinolato)lithium (abbreviated as Liq), 2-(2-pyridyl)phenolate (abbreviated as LiPP), 2-(2-pyridyl)-3-pyridinolatritium (abbreviated as LiPPy), 4-phenyl-2-(2-pyridyl)phenolate (abbreviated as LiPPP), and lithium oxide (LiO2). x ), alkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used.

[0089] Alternatively, an electron-transporting material may be used as the electron injection layer. For example, a compound having a lone pair of electrons and an electron-deficient heteroaromatic ring can be used as the electron-transporting material. Specifically, a compound having at least one of a pyridine ring, a diazine ring (pyrimidine ring, pyrazine ring, pyridazine ring), or a triazine ring can be used.

[0090] Furthermore, it is preferable that the lowest unoccupied molecular orbital (LUMO) of an organic compound containing a lone pair of electrons is between -3.6 eV and -2.3 eV. In addition, the highest occupied molecular orbital (HOMO) level and LUMO level of an organic compound can generally be estimated by methods such as cyclic voltammetry (CV), photoelectron spectroscopy, optical absorption spectroscopy, and inverse photoelectron spectroscopy.

[0091] For example, 4,7-diphenyl-1,10-phenanthroline (abbreviated as BPhen), 2,9-bis(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviated as NBPhen), diquinoxalino[2,3-a:2',3'-c]phenazine (abbreviated as HATNA), and 2,4,6-tris[3'-(pyridine-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviated as TmPPPyTz) can be used in organic compounds containing lone pairs of electrons. NBPhen has a higher glass transition temperature (Tg) and superior heat resistance compared to BPhen.

[0092] It is preferable to have protective layers 131 and 132 on the light-emitting devices 130a, 130b, and 130c. Providing protective layers 131 and 132 can improve the reliability of the light-emitting devices.

[0093] The conductivity of the protective layers 131 and 132 is not required. At least one of an insulating film, a semiconductor film, and a conductive film can be used as the protective layers 131 and 132.

[0094] The presence of inorganic films in the protective layers 131 and 132 prevents oxidation of the counter electrodes 115a, 115b, and 115c, and suppresses the intrusion of impurities (such as moisture and oxygen) into the light-emitting devices 130a, 130b, and 130c, thereby suppressing degradation of the light-emitting devices and improving the reliability of the display device.

[0095] For the protective layers 131 and 132, inorganic insulating films such as oxide insulating films, nitride insulating films, oxidative nitride insulating films, and nitride oxide insulating films can be used. Examples of oxide insulating films include silicon oxide films, aluminum oxide films, gallium oxide films, germanium oxide films, yttrium oxide films, zirconium oxide films, lanthanum oxide films, neodymium oxide films, hafnium oxide films, and tantalum oxide films. Examples of nitride insulating films include silicon nitride films and aluminum nitride films. Examples of oxidative nitride insulating films include silicon oxide nitride films and aluminum oxide nitride films. Examples of nitride oxide insulating films include silicon oxide nitride films and aluminum oxide nitride films.

[0096] In this specification, the term "oxidogenic nitride" refers to a material in which the oxygen content is greater than the nitrogen content, and the term "nitride oxide" refers to a material in which the nitrogen content is greater than the oxygen content.

[0097] The protective layers 131 and 132 preferably each have a nitride insulating film or a nitride oxide insulating film, and more preferably a nitride insulating film.

[0098] Furthermore, the protective layers 131 and 132 may also be made of an inorganic film containing ITO, In-Zn oxide, Ga-Zn oxide, Al-Zn oxide, or indium gallium zinc oxide (also known as In-Ga-Zn oxide or IGZO). The inorganic film is preferably highly resistive, and more specifically, it is preferably more resistive than the counter electrodes 115a, 115b, and 115c. The inorganic film may further contain nitrogen.

[0099] When the light emitted from a light-emitting device is extracted via protective layers 131 and 132, it is preferable that the protective layers 131 and 132 have high transmittance to visible light. For example, ITO, IGZO, and aluminum oxide are preferred because they are inorganic materials with high transmittance to visible light.

[0100] For example, protective layers 131 and 132 can be a laminated structure of an aluminum oxide film and a silicon nitride film on the aluminum oxide film, or a laminated structure of an aluminum oxide film and an IGZO film on the aluminum oxide film. By using such a laminated structure, it is possible to suppress the penetration of impurities (water, oxygen, etc.) into the EL layer.

[0101] Furthermore, the protective layers 131 and 132 may have an organic film. For example, the protective layer 132 may have both an organic film and an inorganic film.

[0102] Furthermore, voids 133 may exist between protective layer 131 and protective layer 132, or within protective layer 132. For example, voids 133 may be formed when different film deposition methods are used for protective layer 131 and protective layer 132. For example, voids 133 may be formed when protective layer 131 is formed using a film deposition apparatus capable of forming a highly covering film, and protective layer 132 is formed using a film deposition apparatus that forms a film with lower coverage than protective layer 131. Specifically, an example is to form protective layer 131 using atomic layer deposition (ALD) and protective layer 132 using sputtering.

[0103] The void 133 contains one or more of the following: air, nitrogen, oxygen, carbon dioxide, and Group 18 elements (typically helium, neon, argon, xenon, krypton, etc.). The void 133 may also contain gases used during the deposition of the protective layer 132. For example, when the protective layer 132 is deposited by sputtering, the void 133 may contain one or more of the Group 18 elements mentioned above. If the void 133 contains gas, the gas can be identified by gas chromatography or other methods. Alternatively, when the protective layer 132 is deposited by sputtering, the protective layer 132 may also contain the gas used during sputtering. In this case, elements such as argon may be detected when the protective layer 132 is analyzed by energy-dispersive X-ray spectroscopy (EDX analysis).

[0104] Furthermore, if the refractive index of the air gap 133 is lower than that of the protective layer 131, light emitted from the first layer 113a, the second layer 113b, or the third layer 113c is reflected at the interface between the protective layer 131 and the air gap 133. This suppresses the incidence of light emitted from the first layer 113a, the second layer 113b, or the third layer 113c on adjacent pixels (or sub-pixels). This suppresses the mixing of light of different colors, thereby improving the display quality of the display device.

[0105] Each end of the pixel electrodes 111a, 111b, and 111c is covered by an insulating layer 121.

[0106] In this embodiment, the display device has each color light-emitting layer arranged in an island-like manner for each light-emitting device, and is manufactured using a so-called side-by-side (SBS) method. Therefore, a display device with higher light extraction efficiency can be realized compared to a configuration that combines a white-emitting light-emitting device and a color filter. Furthermore, since a single-structure light-emitting device can be used, a display device with a lower drive voltage can be realized compared to a configuration that uses a tandem-structure light-emitting device. In addition, by using the SBS method, a display device with lower power consumption can be realized compared to a configuration that combines a white-emitting light-emitting device and a color filter, and a configuration that uses a tandem-structure light-emitting device.

[0107] The display device of this embodiment can reduce the distance between light-emitting devices. Specifically, the distance between light-emitting devices can be 1 μm or less, preferably 500 nm or less, and more preferably 200 nm or less, 100 nm or less, 90 nm or less, 70 nm or less, 50 nm or less, 30 nm or less, 20 nm or less, 15 nm or less, or 10 nm or less. In other words, the distance between the side surface of the first layer 113a and the side surface of the second layer 113b, or the distance between the side surface of the second layer 113b and the side surface of the third layer 113c, has a region of 1 μm or less, preferably a region of 0.5 μm (500 nm) or less, and more preferably a region of 100 nm or less.

[0108] [Example 1 of a method for manufacturing a display device] Next, an example of a method for manufacturing a display device will be explained using Figures 2 to 7. Figures 2A to 2E are top views showing the method for manufacturing a display device. Figures 3A to 3C show the cross-sectional view between the dashed-dotted line X1-X2 and the cross-sectional view between Y1-Y2 in Figure 1A side by side. Figures 4 to 7 are similar to Figure 3.

[0109] Thin films (insulating films, semiconductor films, and conductive films, etc.) that constitute display devices can be formed using sputtering, chemical vapor deposition (CVD), vacuum deposition, pulsed laser deposition (PLD), ALD, and other methods. CVD methods include plasma-enhanced CVD (PECVD) and thermal CVD. One type of thermal CVD is metal-organic CVD (MOCVD).

[0110] Furthermore, thin films (insulating films, semiconductor films, conductive films, etc.) that constitute the display device can be formed by methods such as spin coating, dip coating, spray coating, inkjet printing, dispensing, screen printing, offset printing, doctor knife coating, slit coating, roll coating, curtain coating, and knife coating.

[0111] In particular, vacuum processes such as vapor deposition and solution processes such as spin coating and inkjet can be used to fabricate light-emitting devices. Examples of vapor deposition methods include physical vapor deposition (PVD) methods such as sputtering, ion plating, ion beam deposition, molecular beam deposition, and vacuum deposition, as well as chemical vapor deposition (CVD). Functional layers included in the EL layer (hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, etc.) can be formed by vapor deposition (vacuum deposition, etc.), coating methods (dip coating, die coating, bar coating, spin coating, spray coating, etc.), and printing methods (inkjet, screen printing, offset printing, flexographic printing, gravure, or microcontact printing, etc.).

[0112] Furthermore, when processing the thin film that constitutes the display device, photolithography or the like can be used. Alternatively, the thin film may be processed by nanoimprint lithography, sandblasting, lift-off lithography, or the like. In addition, island-shaped thin films may be directly formed by a film deposition method using a shielding mask such as a metal mask.

[0113] There are two main methods of photolithography. One method involves forming a resist mask on the thin film to be processed, then processing the thin film by etching or other means, and removing the resist mask. The other method involves forming a photosensitive thin film, then exposing and developing it to process the thin film into the desired shape.

[0114] In photolithography, the light used for exposure can be, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or a mixture thereof. Other options include ultraviolet light, KrF laser light, or ArF laser light. Exposure may also be performed using immersion lithography. Furthermore, extreme ultraviolet (EUV) light or X-rays may be used as the light source for exposure. An electron beam can also be used instead of the light source. Using extreme ultraviolet light, X-rays, or an electron beam is preferable because it allows for extremely fine processing. Note that a photomask is not required when exposure is performed by scanning a beam such as an electron beam.

[0115] For etching thin films, methods such as dry etching, wet etching, and sandblasting can be used.

[0116] First, as shown in Figure 3A, pixel electrodes 111a, 111b, 111c, and a conductive layer 123 are formed on the layer 101 containing the transistor. Each pixel electrode is provided on the display section, and the conductive layer 123 is provided on the connection section 140.

[0117] Next, an insulating layer 121 is formed to cover the ends of the pixel electrodes 111a, 111b, and 111c and the ends of the conductive layer 123.

[0118] Then, a first layer 113A is formed on the pixel electrodes 111a, 111b, 111c and the insulating layer 121, and a first sacrificial layer 118A is formed on the first layer 113A, the insulating layer 121, and the conductive layer 123. Figure 3A shows an example in which, in the cross-sectional view between Y1 and Y2, the end of the first layer 113A on the connection portion 140 side is located inside the end of the first sacrificial layer 118A, but is not limited to this. The ends of the first layer 113A and the ends of the first sacrificial layer 118A may be aligned, and the first layer 113A may be provided on the conductive layer 123. For example, by using a mask for defining the film deposition area (also called an area mask or rough metal mask, to distinguish it from a fine metal mask), the region to be film-deposited by the first sacrificial layer 118A and the first layer 113A can be changed.

[0119] The materials that can be used as pixel electrodes are as described above. For forming the pixel electrodes, for example, sputtering or vacuum deposition can be used.

[0120] The insulating layer 121 can be a single-layer structure or a multilayer structure using one or both of an inorganic insulating film and an organic insulating film.

[0121] Examples of organic insulating materials that can be used for the insulating layer 121 include acrylic resin, epoxy resin, polyimide resin, polyamide resin, polyimidoamide resin, polysiloxane resin, benzocyclobutene resin, and phenolic resin. Furthermore, inorganic insulating films that can be used for the insulating layer 121 can be the same inorganic insulating films that can be used for the protective layers 131 and 132.

[0122] When an inorganic insulating film is used as the insulating layer 121 covering the edges of the pixel electrodes, impurities are less likely to enter the light-emitting device compared to when an organic insulating film is used, thereby improving the reliability of the light-emitting device. When an organic insulating film is used as the insulating layer 121 covering the edges of the pixel electrodes, the step coverage is higher compared to when an inorganic insulating film is used, and it is less affected by the shape of the pixel electrodes. Therefore, short circuits in the light-emitting device can be prevented. Specifically, when an organic insulating film is used as the insulating layer 121, the shape of the insulating layer 121 can be processed into a tapered shape or the like. In this specification, a tapered shape refers to a shape in which at least a part of the side surface of the structure is inclined with respect to the substrate surface or the surface to be formed. For example, it is preferable to have a region in which the angle (also called the taper angle) between the inclined side surface and the substrate surface or the surface to be formed is less than 90°.

[0123] The insulating layer 121 is optional. Omitting the insulating layer 121 may increase the aperture ratio of the subpixels. Alternatively, it may be possible to reduce the distance between subpixels, thereby increasing the detail or resolution of the display device.

[0124] The first layer 113A is the layer that later becomes the first layer 113a. Therefore, the configurations applicable to the first layer 113a described above can also be applied to the first layer 113A. The layers constituting the first layer 113A can each be formed by methods such as vapor deposition (including vacuum deposition), transfer, printing, inkjet, and coating. Furthermore, the layers constituting the first layer 113A may be formed using a premixed material.

[0125] The first sacrificial layer 118A is made of a film that has high resistance to processing conditions, such as the first layer 113A and the second layer 113B and third layer 113C formed in a later process, specifically a film with a high etching selectivity ratio. The first sacrificial layer 118A may be a single layer or a multilayer structure.

[0126] For the formation of the first sacrificial layer 118A, for example, sputtering, ALD (including thermal ALD and PEALD), or vacuum deposition can be used. A formation method that causes less damage to the EL layer is preferred, and it is preferable to form the first sacrificial layer 118A using ALD or vacuum deposition rather than sputtering.

[0127] It is preferable to use a film that can be removed by a wet etching method for the first sacrificial layer 118A. By using a wet etching method, the damage inflicted on the first layer 113A during processing of the first sacrificial layer 118A can be reduced compared to when a dry etching method is used.

[0128] In the manufacturing method of the display device of this embodiment, it is desirable that each layer constituting the EL layer (such as the first to fourth layers) is difficult to process during the processing steps of the various sacrificial layers, and that the various sacrificial layers are difficult to process during the processing steps of each layer constituting the EL layer. It is desirable to select the material and processing method of the sacrificial layers and the processing method of the EL layer taking these factors into consideration.

[0129] As the first sacrificial layer 118A, for example, an inorganic film such as a metal film, alloy film, metal oxide film, semiconductor film, or inorganic insulating film can be used.

[0130] The first sacrificial layer 118A can be made of a metallic material such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, and tantalum, or an alloy material containing such a metallic material.

[0131] Furthermore, metal oxides such as In-Ga-Zn oxide can be used for the first sacrificial layer 118A. For example, an In-Ga-Zn oxide film can be formed as the first sacrificial layer 118A using a sputtering method. In addition, indium oxide, In-Zn oxide, In-Sn oxide, indium titanium oxide (In-Ti oxide), indium tin zinc oxide (In-Sn-Zn oxide), indium titanium zinc oxide (In-Ti-Zn oxide), indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide), etc. can be used. Alternatively, indium tin oxide containing silicon can also be used.

[0132] In addition, element M (where M is one or more elements selected from aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium) may be used instead of gallium.

[0133] Furthermore, various inorganic insulating films that can be used for the protective layers 131 and 132 can be used as the first sacrificial layer 118A. In particular, oxide insulating films are preferred because they have higher adhesion to the first layer 113A compared to nitride insulating films. For example, inorganic insulating materials such as aluminum oxide, hafnium oxide, and silicon oxide can be used for the first sacrificial layer 118A. For example, an aluminum oxide film can be formed as the first sacrificial layer 118A using the ALD method. Using the ALD method is preferable because it reduces damage to the substrate (especially the EL layer, etc.).

[0134] Next, as shown in Figure 3B, a resist mask 190a is formed on the first sacrificial layer 118A. The resist mask can be formed by applying a photosensitive resin (photoresist), exposing it to light, and developing it. The resist mask 190a is positioned to overlap with the pixel electrode 111a. Preferably, the resist mask 190a does not overlap with the pixel electrodes 111b and 111c. If the resist mask 190a overlaps with the pixel electrodes 111b and 111c, it is preferable to have an insulating layer 121 in between. If the first layer 113A is provided on the conductive layer 123, it is preferable that the resist mask 190a does not overlap with the conductive layer 123. Also, if the first layer 113A is not provided on the conductive layer 123 by forming the first layer 113A using an area mask or the like, it is preferable to position the resist mask 190a to overlap with the conductive layer 123. This suppresses damage to the conductive layer 123 in later processes.

[0135] As shown in Figure 2A, it is preferable that the resist mask 190a has one island-shaped pattern for each subpixel 110a. Alternatively, the resist mask 190a may have one strip-shaped pattern for multiple subpixels 110a arranged in a row (arranged in the Y direction in Figure 2A).

[0136] Then, as shown in Figure 3C, a portion of the first layer 113A and a portion of the first sacrificial layer 118A are removed using the resist mask 190a. This removes the areas of the first layer 113A and the first sacrificial layer 118A that do not overlap with the resist mask 190a. As a result, the pixel electrodes 111b, 111c and the conductive layer 123 are exposed. The stacked structure of the first layer 113a, the first sacrificial layer 118a, and the resist mask 190a remains on the pixel electrode 111a. After that, the resist mask 190a is removed.

[0137] The first sacrificial layer 118A can be processed by wet etching or dry etching. It is preferable to process the first sacrificial layer 118A by anisotropic etching.

[0138] By using the wet etching method, the damage inflicted on the first layer 113A during processing of the first sacrificial layer 118A can be reduced compared to the dry etching method. When using the wet etching method, it is preferable to use a chemical solution containing, for example, a developer, an aqueous solution of tetramethylammonium hydroxide (TMAH), dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or a mixture thereof.

[0139] Furthermore, when using the dry etching method, the degradation of the first layer 113A can be suppressed by not using an oxygen-containing gas as the etching gas. When using the dry etching method, it is preferable to use a gas containing noble gases (also called rare gases) such as CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, or He as the etching gas.

[0140] Figure 3C shows an example in which the first sacrificial layer 118A and the first layer 113A are processed while the resist mask 190a remains, but the method is not limited to this. For example, if the first sacrificial layer 118A has a multilayer structure, a portion of the layer may be processed using the resist mask 190a, the resist mask 190a may be removed, and then that portion of the layer may be used as a hard mask to process the remaining layer.

[0141] For example, after processing a portion of the first sacrificial layer 118A using a resist mask 190a, the resist mask 190a is removed by ashing using oxygen plasma or the like. At this time, the remaining portion of the first sacrificial layer 118A is located on the outermost surface, and the first layer 113A is not exposed, so damage to the first layer 113A can be suppressed during the removal process of the resist mask 190a. Then, the processed portion of the first sacrificial layer 118A can be used as a hard mask to process the remaining portion of the first sacrificial layer 118A and the first layer 113A, respectively.

[0142] The first layer 113A is preferably processed by anisotropic etching. In particular, anisotropic dry etching is preferred. As the etching gas, it is preferable to use a gas containing nitrogen, a gas containing hydrogen, a gas containing noble gas, a gas containing nitrogen and argon, or a gas containing nitrogen and hydrogen. By not using an oxygen-containing gas as the etching gas, the degradation of the first layer 113A can be suppressed.

[0143] Furthermore, an etching gas containing oxygen may be used. Including oxygen in the etching gas can increase the etching rate. Therefore, etching can be performed under low power conditions while maintaining a sufficiently fast etching rate. This suppresses damage to the first layer 113A. Additionally, it suppresses defects such as the adhesion of reaction products generated during etching.

[0144] Next, as shown in Figure 4A, a second layer 113B is formed on the first sacrificial layer 118a, pixel electrodes 111b, 111c, insulating layer 121, and conductive layer 123, and a second sacrificial layer 118B is formed on the second layer 113B. In Figure 4A, in the cross-sectional view between Y1 and Y2, an example is shown in which the end of the second layer 113B on the connection portion 140 side is located inside the end of the second sacrificial layer 118B, but the invention is not limited to this. The ends of the second layer 113B and the ends of the second sacrificial layer 118B may be aligned, and the second layer 113B may be provided on the conductive layer 123.

[0145] The second layer 113B is the layer that later becomes the second layer 113b. The second layer 113b emits light of a different color than the first layer 113a. The configuration and materials applicable to the second layer 113b are the same as those for the first layer 113a. The second layer 113B can be deposited using the same method as the first layer 113A.

[0146] The second sacrificial layer 118B can be formed using a material applicable to the first sacrificial layer 118A.

[0147] Next, as shown in Figure 4B, a resist mask 190b is formed on the second sacrificial layer 118B. The resist mask 190b is positioned to overlap with the pixel electrode 111b. The resist mask 190b may overlap with the first layer 113a on the insulating layer 121. In this case, the edge of the first layer 113a and the edge of the second layer 113b formed using the resist mask 190b overlap. However, the method for manufacturing the display device of this embodiment further includes a step of processing the first layer 113a and the second layer 113b (a processing step using the resist mask 190d, which will be described later). Therefore, it is possible to suppress overlapping or contact between the first layer 113a and the second layer 113b, and to electrically insulate adjacent light-emitting devices that emit light of different colors from each other. Furthermore, if the resist mask 190b is not connected by an insulating layer 121, it is preferable that it does not overlap with the first layer 113a, the pixel electrodes 111a, and 111c. If the resist mask 190b overlaps with the pixel electrodes 111a and 111c, it is preferable that an insulating layer 121 is connected between them.

[0148] As shown in Figure 2B, it is preferable that the resist mask 190b has one island-shaped pattern for each subpixel 110b. Alternatively, the resist mask 190b may have one strip-shaped pattern for multiple subpixels 110b arranged in a row.

[0149] Then, as shown in Figure 4C, a portion of the second layer 113B and a portion of the second sacrificial layer 118B are removed using the resist mask 190b. This removes the areas of the second layer 113B and the second sacrificial layer 118B that do not overlap with the resist mask 190b. As a result, the first sacrificial layer 118a, the pixel electrode 111c, and the conductive layer 123 are exposed. The stacked structure of the second layer 113b, the second sacrificial layer 118b, and the resist mask 190b remains on the pixel electrode 111b. After that, the resist mask 190b is removed.

[0150] The second sacrificial layer 118B can be processed using a method applicable to the processing of the first sacrificial layer 118A. The second layer 113B can be processed using a method applicable to the processing of the first layer 113A. The resist mask 190b can be removed using a method and timing applicable to the removal of the resist mask 190a.

[0151] Next, as shown in Figure 5A, a third layer 113C is formed on the first sacrificial layer 118a, the second sacrificial layer 118b, the pixel electrode 111c, the insulating layer 121, and the conductive layer 123, and a third sacrificial layer 118C is formed on the third layer 113C. In Figure 5A, in the cross-sectional view between Y1 and Y2, an example is shown in which the end of the third layer 113C on the connection portion 140 side is located inward from the end of the third sacrificial layer 118C, but the invention is not limited to this. The ends of the third layer 113C and the ends of the third sacrificial layer 118C may be aligned, and the third layer 113C may be provided on the conductive layer 123.

[0152] The third layer 113C is the layer that will later become the third layer 113c. The third layer 113c emits light of a different color from the first layer 113a and the second layer 113b. The configuration and materials applicable to the third layer 113c are the same as those for the first layer 113a. The third layer 113C can be deposited using the same method as the first layer 113A.

[0153] The third sacrificial layer 118C can be formed using a material applicable to the first sacrificial layer 118A.

[0154] Next, as shown in Figure 5B, a resist mask 190c is formed on the third sacrificial layer 118C. The resist mask 190c is positioned to overlap with the pixel electrode 111c. The resist mask 190c may overlap with at least one of the first layer 113a and the second layer 113b on the insulating layer 121. In this case, the edge of the first layer 113a or the edge of the second layer 113b overlaps with the edge of the third layer 113c formed using the resist mask 190c. However, the method for manufacturing the display device of this embodiment further includes a step of processing the first layer 113a, the second layer 113b, and the third layer 113c (a processing step using the resist mask 190d, which will be described later). Therefore, it is possible to suppress overlapping or contact between the first layer 113a or the second layer 113b and the third layer 113c, thereby electrically insulating adjacent light-emitting devices that emit light of different colors from each other. In addition, if the resist mask 190c is not separated by the insulating layer 121, it is preferable that it does not overlap with the first layer 113a, the second layer 113b, and the pixel electrodes 111a and 111b. If the resist mask 190c overlaps with the pixel electrodes 111a and 111b, it is preferable to have the insulating layer 121 in between.

[0155] As shown in Figure 2C, it is preferable that the resist mask 190c has one island-shaped pattern for each subpixel 110c. Alternatively, the resist mask 190c may have one strip-shaped pattern for multiple subpixels 110c arranged in a row.

[0156] Then, as shown in Figure 5C, a portion of the third layer 113C and a portion of the third sacrificial layer 118C are removed using the resist mask 190c. This removes the areas of the third layer 113C and the third sacrificial layer 118C that do not overlap with the resist mask 190c. As a result, the first sacrificial layer 118a, the second sacrificial layer 118b, and the conductive layer 123 are exposed. The stacked structure of the third layer 113c, the third sacrificial layer 118c, and the resist mask 190c remains on the pixel electrode 111c. After that, the resist mask 190c is removed.

[0157] The third sacrificial layer 118C can be processed using a method applicable to the processing of the first sacrificial layer 118A. The third layer 113C can be processed using a method applicable to the processing of the first layer 113A. The resist mask 190c can be removed using a method and timing applicable to the removal of the resist mask 190a.

[0158] Next, as shown in Figure 6A, the first sacrificial layer 118a, the second sacrificial layer 118b, and the third sacrificial layer 118c are removed. This exposes the first layer 113a on the pixel electrode 111a, the second layer 113b on the pixel electrode 111b, the third layer 113c on the pixel electrode 111c, and the conductive layer 123.

[0159] The same method as the sacrificial layer processing method can be used for the sacrificial layer removal process. In particular, by using a wet etching method, the damage inflicted on the first layer 113a, the second layer 113b, and the third layer 113c when removing the first sacrificial layer 118a, the second sacrificial layer 118b, and the third sacrificial layer 118c can be reduced compared to when using a dry etching method.

[0160] Next, as shown in Figure 6B, a fourth layer 114 is formed so as to cover the first layer 113a, the second layer 113b, the third layer 113c, the insulating layer 121, and the conductive layer 123, and a counter electrode 115 is formed on the fourth layer 114.

[0161] The fourth layer 114 is the layer that will later become the fourth layers 114a, 114b, and 114c. Therefore, the configurations applicable to the fourth layers 114a, 114b, and 114c described above can also be applied to the fourth layer 114. The layers constituting the fourth layer 114 can each be formed by methods such as vapor deposition (including vacuum deposition), transfer, printing, inkjet, and coating. Furthermore, the layers constituting the fourth layer 114 may be formed using a premixed material.

[0162] The materials that can be used as the counter electrode 115 are as described above. For the formation of the counter electrode 115, for example, sputtering or vacuum deposition can be used.

[0163] Next, as shown in Figure 6C, a resist mask 190d is formed on the counter electrode 115.

[0164] The resist mask 190d is provided in a position that overlaps with the pixel electrodes 111a, 111b, and 111c. Preferably, the resist mask 190d is not provided in the region between pixel electrode 111a and pixel electrode 111b, the region between pixel electrode 111b and pixel electrode 111c, and the region between pixel electrode 111a and pixel electrode 111c when viewed from above.

[0165] Figure 2D shows an example in which an opening (also called a slit) of the resist mask 190d is provided in the region between two subpixels that exhibit light of different colors. In each of the regions between subpixels 110a and 110b, between subpixels 110b and 110c, and between subpixels 110a and 110c, there are areas where the resist mask 190d is not provided.

[0166] Furthermore, Figure 2E shows an example in which the resist mask 190d has portions that overlap with multiple subpixels 110a, portions that overlap with multiple subpixels 110b, and portions that overlap with multiple subpixels 110c, separated from each other. Thus, the resist mask 190d may be composed of multiple strip-shaped patterns. Each strip-shaped pattern is provided so as to overlap with a portion of the conductive layer 123 provided on the connection portion 140. This allows the counter electrode 115 to remain on the connection portion 140, and enables an electrical connection between the counter electrode 115 and the conductive layer 123.

[0167] Next, as shown in Figure 7A, the resist mask 190d is used to remove a portion of the fourth layer 114 and the counter electrode 115. This removes the fourth layer 114 and the counter electrode 115 that are located in the region between the two light-emitting devices that emit light of different colors. The stacked structure of the first layer 113a, the fourth layer 114a, the counter electrode 115a, and the resist mask 190d remains on the pixel electrode 111a. Similarly, the stacked structure of the second layer 113b, the fourth layer 114b, the counter electrode 115b, and the resist mask 190d remains on the pixel electrode 111b, and the stacked structure of the third layer 113c, the fourth layer 114c, the counter electrode 115c, and the resist mask 190d remains on the pixel electrode 111c. The counter electrodes 115a, 115b, and 115c also remain on the conductive layer 123. Depending on the shape of the resist mask 190d, the counter electrodes 115a, 115b, and 115c may form a continuous film (corresponding to the shape of the resist mask 190d shown in Figure 2D).

[0168] The counter electrode 115 can be processed by wet etching or dry etching. It is preferable to process the counter electrode 115 by anisotropic etching.

[0169] The fourth layer 114 can be processed using a method applicable to the processing of the first layer 113A.

[0170] In the processing step using the resist mask 190d, parts of the first layer 113a, parts of the second layer 113b, and parts of the third layer 113c located on the insulating layer 121 may also be removed. For example, if two of the first layer 113a, the second layer 113b, and the third layer 113c overlap or come into contact on the insulating layer 121, removing these parts allows for electrical isolation between light-emitting devices that emit light of different colors. Therefore, crosstalk can be suppressed.

[0171] Next, as shown in Figure 7B, the resist mask 190d is removed. Note that the resist mask 190d may also be removed after processing the counter electrode 115. In this case, the fourth layer 114 can be processed using the counter electrodes 115a, 115b, and 115c as a hard mask.

[0172] Then, as shown in Figure 7C, a protective layer 131 is formed on the counter electrodes 115a, 115b, and 115c, and a protective layer 132 is formed on the protective layer 131.

[0173] The materials that can be used for protective layers 131 and 132 are as described above. Methods for forming protective layers 131 and 132 include vacuum deposition, sputtering, CVD, and ALD. Protective layers 131 and 132 may be formed using different deposition methods. Furthermore, protective layers 131 and 132 may each be single-layer or multi-layer structures.

[0174] Here, we show an example in which a void 133 is formed by the deposition of protective layers 131 and 132, but the void 133 does not necessarily have to be formed. In this case, the space between light-emitting devices 130a and 130b, and between light-emitting devices 130b and 130c, will be filled with protective layer 132.

[0175] Subsequently, the display device 100 shown in Figure 1B can be fabricated by bonding the substrate 120 using the resin layer 119.

[0176] [Example of a method for manufacturing a display device 2] A display device with the configuration shown in Figures 9A and 9B may be manufactured by performing the steps shown in Figures 8A to 8C after the steps shown in Figure 7C. Below, an example of a method for manufacturing a display device will be explained using Figures 2F, 8, and 9. Figure 2F is a top view showing the method for manufacturing a display device. Figures 8A to 8C show the cross-sectional view between the dashed-dotted lines X1-X2 and the cross-sectional view between Y1-Y2 in Figure 1A side by side. Figure 9A is a cross-sectional view between the dashed-dotted lines X1-X2 in Figure 1A, and Figure 9B is a cross-sectional view between the dashed-dotted lines X3-X4 in Figure 1A.

[0177] After the process shown in Figure 7C, a resist mask 190e is formed on the protective layer 132, as shown in Figure 8A.

[0178] The resist mask 190e is provided in a position that overlaps with the pixel electrodes 111a, 111b, and 111c. Preferably, the resist mask 190e is not provided in the region between two adjacent pixel electrodes 111a, the region between two adjacent pixel electrodes 111b, and the region between two adjacent pixel electrodes 111c when viewed from above. Furthermore, preferably, the resist mask 190e is not provided in a region that overlaps with the conductive layer 123.

[0179] In Figure 2F, there are areas where the resist mask 190e is not provided in the region between two adjacent subpixels 110a, the region between two adjacent subpixels 110b, and the region between two adjacent subpixels 110c. Furthermore, the resist mask 190e is not provided in the connection portion 140. Note that the ends of the resist mask 190e shown in Figure 2F may be connected by regions not shown. In this case, it can be said that openings (also called slits) of the resist mask 190e are provided in the regions between two adjacent subpixels that exhibit the same color light. Alternatively, the resist mask 190e may have multiple band-shaped patterns that overlap with subpixels 110a, 110b, and 110c arranged in a single row in the X direction.

[0180] Next, as shown in Figure 8B, a portion of the protective layers 131 and 132 is removed using the resist mask 190e. This removes the protective layers 131 and 132 contained in the region between two light-emitting devices that emit light of the same color. In this region, the counter electrodes 115a, 115b, and 115c are exposed. In addition, the portions of the protective layers 131 and 132 that overlap with the conductive layer 123 are also removed. As a result, in the portion shown in Figure 8B, the counter electrode 115b is exposed.

[0181] Then, the resist mask 190e is removed. Note that the resist mask 190e may also be removed after processing the protective layer 132. In this case, the protective layer 131 can be processed using the protective layer 132 as a hard mask.

[0182] Then, as shown in Figure 8C, a conductive layer 134 is formed on the counter electrodes 115a, 115b, 115c and the protective layer 132. As a result, the counter electrodes 115a, 115b, 115c and the conductive layer 123 are electrically connected to the conductive layer 134.

[0183] The conductive layer 134 can be formed using a material applicable to the pixel electrode and the counter electrode. When the conductive layer 134 is provided on the side from which light is extracted, the conductive layer 134 is formed using a conductive material that transmits visible light.

[0184] The conductive layer 134 is provided over a larger area than the counter electrodes 115a, 115b, and 115c, and functions as auxiliary wiring. By providing the conductive layer 134 across the entire surface, voltage drops caused by the resistance of the counter electrodes 115a, 115b, and 115c are suppressed, reducing brightness unevenness in the display device and achieving high display quality.

[0185] Subsequently, the display device shown in Figures 9A and 9B can be fabricated by bonding the substrate 120 using the resin layer 119.

[0186] The display device shown in Figure 9A differs from the display device 100 shown in Figure 1B in that it has a conductive layer 134 on a protective layer 132. As shown in Figure 9B, in the cross section between the dashed line X3-X4 in Figure 1A, a fourth layer 114a, 114b, 114c is provided on the insulating layer 121, and further, counter electrodes 115a, 115b, 115c are provided, with the conductive layer 134 covering them.

[0187] As described above, in the method for manufacturing the display device of this embodiment, the island-shaped EL layer is not formed using a fine metal mask, but rather by processing after the EL layer has been deposited on one surface. Therefore, the island-shaped EL layer can be formed with a uniform thickness.

[0188] The first, second, and third layers constituting each color of light-emitting device are formed in separate processes. Therefore, each EL layer can be fabricated with a configuration (material, film thickness, etc.) suitable for each color of light-emitting device. This makes it possible to produce light-emitting devices with excellent characteristics.

[0189] The display device of this embodiment has a configuration in which the overlapping or contact of the first layer, second layer, and third layer constituting the light-emitting devices of each color is suppressed. Therefore, crosstalk is suppressed, and a display device with high definition or high resolution and high display quality can be realized.

[0190] This embodiment can be combined with other embodiments as appropriate. Furthermore, if multiple configuration examples are shown within a single embodiment in this specification, these configuration examples can be combined as appropriate.

[0191] (Embodiment 2) In this embodiment, a display device according to one aspect of the present invention will be described with reference to Figures 10 and 11.

[0192] The display device of this embodiment can be a high-resolution display device or a large-screen display device. Therefore, the display device of this embodiment can be used in electronic devices with relatively large screens, such as television sets, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as in the display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game consoles, personal information terminals, and audio playback devices.

[0193] [Display device 100A] Figure 10 shows a perspective view of the display device 100A, and Figure 11A shows a cross-sectional view of the display device 100A.

[0194] The display device 100A has a configuration in which substrate 152 and substrate 151 are bonded together. In Figure 10, substrate 152 is clearly indicated by a dashed line.

[0195] The display device 100A includes a display unit 162, a circuit 164, wiring 165, etc. Figure 10 shows an example in which IC 173 and FPC 172 are mounted on the display device 100A. Therefore, the configuration shown in Figure 10 can also be described as a display module having the display device 100A, an IC (integrated circuit), and an FPC.

[0196] For example, a scan line drive circuit can be used as circuit 164.

[0197] Wiring 165 has the function of supplying signals and power to the display unit 162 and the circuit 164. These signals and power are input to wiring 165 from an external source via FPC 172 or from IC 173.

[0198] Figure 10 shows an example in which IC 173 is mounted on the substrate 151 using a COG (Chip On Glass) method or COF (Chip On Film) method. IC 173 can be an IC having, for example, a scan line drive circuit or a signal line drive circuit. Note that the display device 100A and the display module may be configured without an IC. Alternatively, the IC may be mounted on an FPC using a COF method or the like.

[0199] Figure 11A shows an example of a cross-section obtained by cutting a portion of the display device 100A, including the FPC 172, a portion of the circuit 164, a portion of the display unit 162, and a portion of the area including the end.

[0200] The display device 100A shown in Figure 11A includes a transistor 201, a transistor 205, a light-emitting device 130a that emits red light, a light-emitting device 130b that emits green light, and a light-emitting device 130c that emits blue light, etc., between substrates 151 and 152.

[0201] Here, if a pixel of a display device has three types of subpixels, each having a light-emitting device that emits light of different colors, examples of such three subpixels include subpixels of three colors: R, G, and B; and subpixels of three colors: yellow (Y), cyan (C), and magenta (M). If there are four such subpixels, examples of such four subpixels include subpixels of four colors: R, G, B, and white (W); and subpixels of four colors: R, G, B, and Y.

[0202] The protective layer 132 and the substrate 152 are bonded together via an adhesive layer 142. For sealing the light-emitting device, a solid sealing structure or a hollow sealing structure can be applied. In Figure 11A, the space between substrate 152 and substrate 151 is filled with the adhesive layer 142, demonstrating a solid sealing structure. Alternatively, the space may be filled with an inert gas (such as nitrogen or argon), demonstrating a hollow sealing structure. In this case, the adhesive layer 142 may be provided so as not to overlap with the light-emitting device. Furthermore, the space may be filled with a resin different from the frame-shaped adhesive layer 142.

[0203] The light-emitting devices 130a, 130b, and 130c each have the same structure as the stacked structure shown in Figure 1B, except that they have an optical adjustment layer between the pixel electrode and the EL layer. Light-emitting device 130a has an optical adjustment layer 126a, light-emitting device 130b has an optical adjustment layer 126b, and light-emitting device 130c has an optical adjustment layer 126c. Details of the light-emitting devices can be found in Embodiment 1. In addition, protective layers 131 and 132 are provided on the light-emitting devices 130a, 130b, and 130c, respectively.

[0204] Figure 11A shows an example where the thickness of optical adjustment layer 126a is greater than the thickness of optical adjustment layer 126b, and the thickness of optical adjustment layer 126b is greater than the thickness of optical adjustment layer 126c. Preferably, the thickness of optical adjustment layer 126a is set to enhance red light, the thickness of optical adjustment layer 126b is set to enhance green light, and the thickness of optical adjustment layer 126c is set to enhance blue light. This makes it possible to realize a microcavity structure and improve the color purity of the light emitted by each light-emitting device.

[0205] The optical adjustment layer is preferably formed using a conductive material that has transparency to visible light, among conductive materials that can be used as electrodes for light-emitting devices.

[0206] The pixel electrodes 111a, 111b, and 111c are each connected to the conductive layer 222b of the transistor 205 through an opening provided in the insulating layer 214.

[0207] The edges of the pixel electrodes and the optical adjustment layer are covered by an insulating layer 121. The pixel electrodes contain a material that reflects visible light, and the counter electrodes contain a material that transmits visible light.

[0208] The light emitted by the light-emitting device is projected onto the substrate 152. It is preferable to use a material with high transparency to visible light for the substrate 152.

[0209] The laminated structure from the substrate 151 to the insulating layer 214 corresponds to the layer 101 containing the transistor in Embodiment 1.

[0210] Both transistors 201 and 205 are formed on the substrate 151. These transistors can be manufactured using the same materials and the same process.

[0211] On the substrate 151, insulating layers 211, 213, 215, and 214 are provided in this order. A portion of insulating layer 211 functions as a gate insulating layer for each transistor. A portion of insulating layer 213 functions as a gate insulating layer for each transistor. Insulating layer 215 is provided covering the transistors. Insulating layer 214 is provided covering the transistors and functions as a planarization layer. The number of gate insulating layers and insulating layers covering the transistors are not limited and may be a single layer or two or more layers, respectively.

[0212] It is preferable to use a material that does not easily allow impurities such as water and hydrogen to diffuse into at least one layer of the insulating layer covering the transistor. This allows the insulating layer to function as a barrier layer. With such a configuration, the diffusion of impurities from the outside into the transistor can be effectively suppressed, thereby improving the reliability of the display device.

[0213] It is preferable to use inorganic insulating films for insulating layer 211, insulating layer 213, and insulating layer 215. Examples of inorganic insulating films that can be used include silicon nitride film, silicon oxide nitride film, silicon oxide film, silicon nitride oxide film, aluminum oxide film, and aluminum nitride film. Alternatively, hafnium oxide film, yttrium oxide film, zirconium oxide film, gallium oxide film, tantalum oxide film, magnesium oxide film, lanthanum oxide film, cerium oxide film, and neodymium oxide film may also be used. Furthermore, two or more of the above insulating films may be laminated together.

[0214] Here, organic insulating films often have lower barrier properties than inorganic insulating films. Therefore, it is preferable that the organic insulating film has an opening near the edge of the display device 100A. This prevents impurities from entering through the organic insulating film from the edge of the display device 100A. Alternatively, the organic insulating film may be formed so that its edge is inward from the edge of the display device 100A, so that the organic insulating film is not exposed at the edge of the display device 100A.

[0215] An organic insulating film is preferred for the insulating layer 214, which functions as a planarizing layer. Examples of materials that can be used as the organic insulating film include acrylic resins, polyimide resins, epoxy resins, polyamide resins, polyimidoamide resins, siloxane resins, benzocyclobutene resins, phenolic resins, and precursors of these resins.

[0216] In the region 228 shown in Figure 11A, an opening is formed in the insulating layer 214. This prevents impurities from entering the display unit 162 from the outside through the insulating layer 214, even when an organic insulating film is used for the insulating layer 214. Therefore, the reliability of the display device 100A can be improved.

[0217] Transistors 201 and 205 have a conductive layer 221 that functions as a gate, an insulating layer 211 that functions as a gate insulating layer, conductive layers 222a and 222b that function as source and drain, a semiconductor layer 231, an insulating layer 213 that functions as a gate insulating layer, and a conductive layer 223 that functions as a gate. Here, the same hatching pattern is applied to multiple layers obtained by processing the same conductive film. The insulating layer 211 is located between the conductive layer 221 and the semiconductor layer 231. The insulating layer 213 is located between the conductive layer 223 and the semiconductor layer 231.

[0218] The transistor structure of the display device of this embodiment is not particularly limited. For example, planar transistors, staggered transistors, inverse staggered transistors, etc., can be used. Furthermore, either a top-gate or bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below the semiconductor layer in which the channel is formed.

[0219] Transistors 201 and 205 are configured in which a semiconductor layer on which a channel is formed is sandwiched between two gates. The transistors may be driven by connecting the two gates and supplying them with the same signal. Alternatively, the threshold voltage of the transistors may be controlled by applying a potential to control the threshold voltage to one of the two gates and a potential to drive the other gate.

[0220] The crystallinity of the semiconductor material used in the transistor is not particularly limited; amorphous semiconductors, single-crystal semiconductors, or semiconductors with crystalline properties other than single crystals (microcrystalline semiconductors, polycrystalline semiconductors, or semiconductors with crystalline regions in part) may be used. Using a single-crystal semiconductor or a semiconductor with crystalline properties is preferable because it can suppress the degradation of transistor characteristics.

[0221] The semiconductor layer of the transistor preferably has a metal oxide (also called an oxide semiconductor). In other words, the display device of this embodiment preferably uses a transistor (hereinafter referred to as an OS transistor) that uses a metal oxide in the channel formation region. Alternatively, the semiconductor layer of the transistor may have silicon. Examples of silicon include amorphous silicon and crystalline silicon (low-temperature polysilicon, single-crystal silicon, etc.).

[0222] The semiconductor layer preferably comprises, for example, indium, M (where M is one or more selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more selected from aluminum, gallium, yttrium, and tin.

[0223] In particular, it is preferable to use an oxide (also written as IGZO) containing indium (In), gallium (Ga), and zinc (Zn) as the semiconductor layer.

[0224] When the semiconductor layer is an In-M-Zn oxide, it is preferable that the atomic ratio of In in the In-M-Zn oxide is equal to or greater than the atomic ratio of M. Examples of such In-M-Zn oxide atomic ratios of metal elements include compositions where In:M:Zn=1:1:1 or close to it, In:M:Zn=1:1:1.2 or close to it, In:M:Zn=2:1:3 or close to it, In:M:Zn=3:1:2 or close to it, In:M:Zn=4:2:3 or close to it, In:M:Zn=4:2:4.1 or close to it, In:M:Zn=5:1:3 or close to it, In:M:Zn=5:1:6 or close to it, In:M:Zn=5:1:7 or close to it, In:M:Zn=5:1:8 or close to it, In:M:Zn=6:1:6 or close to it, In:M:Zn=5:2:5 or close to it, and so on. Note that "close to it" compositions include a range of ±30% of the desired atomic ratio.

[0225] For example, when describing a composition with an atomic ratio of In:Ga:Zn = 4:2:3 or a similar ratio, it includes cases where, when In is set to 4, Ga is between 1 and 3, and Zn is between 2 and 4. Also, when describing a composition with an atomic ratio of In:Ga:Zn = 5:1:6 or a similar ratio, it includes cases where, when In is set to 5, Ga is greater than 0.1 and 2 or less, and Zn is between 5 and 7. Furthermore, when describing a composition with an atomic ratio of In:Ga:Zn = 1:1:1 or a similar ratio, it includes cases where, when In is set to 1, Ga is greater than 0.1 and 2 or less, and Zn is greater than 0.1 and 2 or less.

[0226] The transistors in circuit 164 and the transistors in display unit 162 may have the same structure or different structures. The structures of the multiple transistors in circuit 164 may all be the same or there may be two or more different structures. Similarly, the structures of the multiple transistors in display unit 162 may all be the same or there may be two or more different structures.

[0227] Figures 11B and 11C show other examples of transistor configurations.

[0228] Transistors 209 and 210 each have a conductive layer 221 that functions as a gate, an insulating layer 211 that functions as a gate insulating layer, a semiconductor layer 231 having a channel forming region 231i and a pair of low-resistance regions 231n, a conductive layer 222a connected to one of the pair of low-resistance regions 231n, a conductive layer 222b connected to the other of the pair of low-resistance regions 231n, an insulating layer 225 that functions as a gate insulating layer, a conductive layer 223 that functions as a gate, and an insulating layer 215 covering the conductive layer 223. The insulating layer 211 is located between the conductive layer 221 and the channel forming region 231i. The insulating layer 225 is located at least between the conductive layer 223 and the channel forming region 231i. Furthermore, an insulating layer 218 covering the transistor may be provided.

[0229] In the transistor 209 shown in Figure 11B, an example is shown where the insulating layer 225 covers the top and sides of the semiconductor layer 231. The conductive layers 222a and 222b are connected to the low-resistance region 231n through openings provided in the insulating layers 225 and 215, respectively. Of the conductive layers 222a and 222b, one functions as the source and the other as the drain.

[0230] On the other hand, in the transistor 210 shown in Figure 11C, the insulating layer 225 overlaps with the channel formation region 231i of the semiconductor layer 231, but does not overlap with the low-resistance region 231n. For example, the structure shown in Figure 11C can be fabricated by processing the insulating layer 225 using the conductive layer 223 as a mask. In Figure 11C, an insulating layer 215 is provided covering the insulating layer 225 and the conductive layer 223, and the conductive layer 222a and conductive layer 222b are connected to the low-resistance region 231n, respectively, through openings in the insulating layer 215.

[0231] A connection portion 204 is provided in the region of substrate 151 where substrate 152 does not overlap. At the connection portion 204, wiring 165 is electrically connected to FPC 172 via conductive layer 166 and connection layer 242. The conductive layer 166 is shown as an example of a laminated structure consisting of a conductive film obtained by processing the same conductive film as the pixel electrode and a conductive film obtained by processing the same conductive film as the optical adjustment layer 126c. The conductive layer 166 is exposed on the upper surface of the connection portion 204. This allows the connection portion 204 and FPC 172 to be electrically connected via the connection layer 242.

[0232] It is preferable to provide a light-shielding layer 117 on the surface of the substrate 152 that faces the substrate 151. Various optical components can be placed on the outside of the substrate 152 (the surface opposite to the substrate 151 side). Examples of optical components include polarizing plates, phase difference plates, light diffusion layers (such as diffusion films), anti-reflective layers, and light-collecting films. Furthermore, an antistatic film to suppress the adhesion of dust, a water-repellent film to make it difficult for dirt to adhere, a hard coat film to suppress the occurrence of scratches during use, and an impact-absorbing layer may be placed on the outside of the substrate 152.

[0233] By providing protective layers 131 and 132 that cover the light-emitting device, it is possible to suppress the ingress of impurities such as water into the light-emitting device and improve the reliability of the light-emitting device.

[0234] In the region 228 near the edge of the display device 100A, it is preferable that the insulating layer 215 and the protective layer 131 or protective layer 132 are in contact with each other through an opening in the insulating layer 214. In particular, it is preferable that the inorganic insulating films are in contact with each other. This makes it possible to suppress the entry of impurities into the display unit 162 from the outside through the organic insulating film. Therefore, the reliability of the display device 100A can be improved.

[0235] Substrates 151 and 152 can be made of glass, quartz, ceramic, sapphire, resin, metal, alloy, semiconductor, etc., respectively. The substrate on the side that extracts light from the light-emitting device should be made of a material that transmits the light. Using flexible materials for substrates 151 and 152 can increase the flexibility of the display device. Alternatively, a polarizing plate may be used as substrate 151 or substrate 152.

[0236] Substrates 151 and 152 can be made from polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyacrylonitrile resin, acrylic resin, polyimide resin, polymethyl methacrylate resin, polycarbonate (PC) resin, polyethersulfone (PES) resin, polyamide resin (nylon, aramid, etc.), polysiloxane resin, cycloolefin resin, polystyrene resin, polyamide-imide resin, polyurethane resin, polyvinyl chloride resin, polyvinylidene chloride resin, polypropylene resin, polytetrafluoroethylene (PTFE) resin, ABS resin, cellulose nanofiber, etc. One or both of substrates 151 and 152 may be made of glass of a thickness sufficient to provide flexibility.

[0237] Furthermore, when a circular polarizing plate is superimposed on a display device, it is preferable to use a substrate with high optical isotropy for the substrate of the display device. A substrate with high optical isotropy has low birefringence (or a small amount of birefringence).

[0238] For substrates with high optical isotropy, the absolute value of the retardation (phase difference) is preferably 30 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less.

[0239] Examples of films with high optical isotropy include triacetylcellulose (TAC, also known as cellulose triacetate) film, cycloolefin polymer (COP) film, cycloolefin copolymer (COC) film, and acrylic film.

[0240] Furthermore, when using a film as the substrate, the film may absorb water, potentially causing wrinkles or other shape changes in the display panel. Therefore, it is preferable to use a film with low water absorption for the substrate. For example, it is preferable to use a film with a water absorption rate of 1% or less, more preferable to use a film with a water absorption rate of 0.1% or less, and even more preferable to use a film with a water absorption rate of 0.01% or less.

[0241] Various types of curing adhesives can be used as the adhesive layer, including UV-curing adhesives, reaction-curing adhesives, thermosetting adhesives, and anaerobic adhesives. Examples of these adhesives include epoxy resins, acrylic resins, silicone resins, phenolic resins, polyimide resins, imide resins, PVC (polyvinyl chloride) resins, PVB (polyvinyl butyral) resins, and EVA (ethylene vinyl acetate) resins. Materials with low moisture permeability, such as epoxy resins, are particularly preferred. Two-component mixed resins may also be used. Adhesive sheets may also be used.

[0242] As the connecting layer 242, an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), etc., can be used.

[0243] Materials that can be used for conductive layers such as the gate, source, and drain of transistors, as well as various wirings and electrodes that constitute display devices, include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, and tungsten, as well as alloys mainly composed of these metals. Films containing these materials can be used as single layers or in a multilayer structure.

[0244] Furthermore, conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, and zinc oxide containing gallium, or graphene can be used as the light-transmitting conductive material. Alternatively, metallic materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, and titanium, or alloy materials containing such metallic materials, can be used. Alternatively, nitrides of such metallic materials (e.g., titanium nitride) may be used. When using metallic materials or alloy materials (or their nitrides), it is preferable to make them thin enough to be light-transmitting. In addition, a laminated film of the above materials can be used as a conductive layer. For example, using a laminated film of a silver-magnesium alloy and indium tin oxide is preferable because it can enhance conductivity. These can also be used as conductive layers for various wirings and electrodes that constitute a display device, and as conductive layers (conductive layers that function as pixel electrodes or counter electrodes) in light-emitting devices.

[0245] Examples of insulating materials that can be used for each insulating layer include resins such as acrylic resin and epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxide nitride, silicon nitride, silicon oxide, and aluminum oxide.

[0246] This embodiment can be combined with other embodiments as appropriate.

[0247] (Embodiment 3) In this embodiment, a display device according to one aspect of the present invention will be described with reference to Figures 12 to 15.

[0248] The display device of this embodiment can be a high-definition display device. Therefore, the display device of this embodiment can be used in the display section of wearable devices that can be worn on the head, such as information terminals (wearable devices) such as wristwatches and bracelets, as well as VR devices such as head-mounted displays and AR devices such as glasses.

[0249] [Display Module] Figure 12A shows a perspective view of the display module 280. The display module 280 includes a display device 100B and an FPC 290. Note that the display device included in the display module 280 is not limited to the display device 100B, but may be the display device 100C or the display device 100D, which will be described later.

[0250] The display module 280 has substrates 291 and 292. The display module 280 has a display unit 281. The display unit 281 is an area in the display module 280 that displays an image, and is an area in which light from each pixel provided in the pixel unit 284, which will be described later, can be seen.

[0251] Figure 12B shows a schematic perspective view illustrating the configuration of the substrate 291. On the substrate 291, a circuit section 282, a pixel circuit section 283 on the circuit section 282, and a pixel section 284 on the pixel circuit section 283 are stacked. In addition, a terminal section 285 for connecting to the FPC 290 is provided in the portion of the substrate 291 that does not overlap with the pixel section 284. The terminal section 285 and the circuit section 282 are electrically connected by a wiring section 286, which is composed of multiple wires.

[0252] The pixel section 284 has multiple pixels 284a arranged periodically. A magnified view of a single pixel 284a is shown on the right side of Figure 12B. Each pixel 284a has light-emitting devices 130a, 130b, and 130c, each with a different emission color. The multiple light-emitting devices can be arranged in a stripe pattern as shown in Figure 12B. Various arrangement methods for the light-emitting devices, such as a delta pattern or a pentile pattern, can also be applied.

[0253] The pixel circuit section 283 has a plurality of pixel circuits 283a arranged periodically.

[0254] A single pixel circuit 283a is a circuit that controls the light emission of three light-emitting devices in a single pixel 284a. A single pixel circuit 283a may be configured to have three circuits that control the light emission of one light-emitting device. For example, a pixel circuit 283a can be configured to have at least one selection transistor, one current control transistor (drive transistor), and a capacitive element for each light-emitting device. In this case, a gate signal is input to the gate of the selection transistor, and a source signal is input to either the source or the drain. This realizes an active-matrix type display device.

[0255] The circuit section 282 has circuits for driving each pixel circuit 283a of the pixel circuit section 283. For example, it is preferable to have one or both of a gate line drive circuit and a source line drive circuit. In addition, it may have at least one of the following: an arithmetic circuit, a memory circuit, and a power supply circuit.

[0256] The FPC290 functions as wiring for supplying video signals or power potential, etc., to the circuit section 282 from an external source. An IC may also be mounted on the FPC290.

[0257] The display module 280 can be configured such that one or both of the pixel circuit section 283 and the circuit section 282 are superimposed on the lower side of the pixel section 284, thereby enabling an extremely high aperture ratio (effective display area ratio) of the display section 281. For example, the aperture ratio of the display section 281 can be 40% or more and less than 100%, preferably 50% or more and 95%, and more preferably 60% or more and 95%. Furthermore, it is possible to arrange the pixels 284a at an extremely high density, enabling an extremely high resolution of the display section 281. For example, it is preferable that the pixels 284a in the display section 281 are arranged with a resolution of 20000 ppi or more, preferably 3000 ppi or more, more preferably 5000 ppi or more, and even more preferably 6000 ppi or more, and with a resolution of 20000 ppi or less, or 30000 ppi or less.

[0258] Because such a display module 280 is extremely high-resolution, it can be suitably used in VR devices such as head-mounted displays, or in glasses-type AR devices. For example, even in a configuration where the display part of the display module 280 is viewed through lenses, the display module 280 has an extremely high-resolution display part 281, so even when the display part is magnified with lenses, pixels are not visible, allowing for a highly immersive display. Furthermore, the display module 280 is not limited to this, and can be suitably used in electronic devices with relatively small display parts. For example, it can be suitably used in the display part of wearable electronic devices such as wristwatches.

[0259] [Display device 100B] The display device 100B shown in Figure 13 includes a substrate 301, light-emitting devices 130a, 130b, and 130c, a capacitor 240, and a transistor 310.

[0260] Substrate 301 corresponds to substrate 291 in Figures 12A and 12B. The laminated structure from substrate 301 to insulating layer 255 corresponds to layer 101 containing the transistor in Embodiment 1.

[0261] The transistor 310 is a transistor having a channel-forming region in the substrate 301. The substrate 301 can be a semiconductor substrate such as a single-crystal silicon substrate. The transistor 310 comprises a portion of the substrate 301, a conductive layer 311, a low-resistance region 312, an insulating layer 313, and an insulating layer 314. The conductive layer 311 functions as a gate electrode. The insulating layer 313 is located between the substrate 301 and the conductive layer 311 and functions as a gate insulating layer. The low-resistance region 312 is a region of the substrate 301 doped with impurities and functions as either a source or a drain. The insulating layer 314 is provided covering the side surface of the conductive layer 311.

[0262] Furthermore, an element isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301.

[0263] Furthermore, an insulating layer 261 is provided covering the transistor 310, and a capacitance 240 is provided on the insulating layer 261.

[0264] Capacitor 240 has a conductive layer 241, a conductive layer 245, and an insulating layer 243 located between them. The conductive layer 241 functions as one electrode of the capacitor 240, the conductive layer 245 functions as the other electrode of the capacitor 240, and the insulating layer 243 functions as the dielectric of the capacitor 240.

[0265] The conductive layer 241 is provided on the insulating layer 261 and embedded in the insulating layer 254. The conductive layer 241 is electrically connected to either the source or drain of the transistor 310 by a plug 271 embedded in the insulating layer 261. The insulating layer 243 is provided covering the conductive layer 241. The conductive layer 245 is provided in the region that overlaps with the conductive layer 241 via the insulating layer 243.

[0266] Covering a capacity of 240, an insulating layer 255 is provided, and light-emitting devices 130a, 130b, 130c, etc. are provided on the insulating layer 255. In this embodiment, an example is shown in which the light-emitting devices 130a, 130b, 130c have the same structure as the stacked structure shown in FIG. 1B. Further, protective layers 131 are provided on the light-emitting devices 130a, 130b, 130c, respectively. A protective layer 132 is provided on the protective layer 131, and a substrate 120 is bonded by a resin layer 119 on the protective layer 132. A gap 133 is provided between the protective layer 131 and the protective layer 132. Details of the components from the light-emitting device to the substrate 120 can be referred to in Embodiment 1. The substrate 120 corresponds to the substrate 292 in FIG. 12A.

[0267] The pixel electrode of the light-emitting device is electrically connected to one of the source or drain of the transistor 310 by a plug 256 embedded in the insulating layer 255, a conductive layer 241 embedded in the insulating layer 254, and a plug 271 embedded in the insulating layer 261.

[0268] [Display device 100C] The display device 100C shown in FIG. 14 is mainly different from the display device 100B in that the configuration of the transistor is different. Note that the description of the same parts as those of the display device 100B may be omitted.

[0269] The transistor 320 is a transistor (OS transistor) in which a metal oxide (also referred to as an oxide semiconductor) is applied to a semiconductor layer in which a channel is formed.

[0270] The transistor 320 includes a semiconductor layer 321, an insulating layer 323, a conductive layer 324, a pair of conductive layers 325, an insulating layer 326, and a conductive layer 327.

[0271] The substrate 331 corresponds to the substrate 291 in FIGS. 12A and 12B. The stacked structure from the substrate 331 to the insulating layer 255 corresponds to the layer 101 including the transistor in Embodiment 1. As the substrate 331, an insulating substrate or a semiconductor substrate can be used.

[0272] An insulating layer 332 is provided on the substrate 331. The insulating layer 332 functions as a barrier layer that prevents impurities such as water or hydrogen from diffusing from the substrate 331 to the transistor 320, and prevents oxygen from detaching from the semiconductor layer 321 to the insulating layer 332. As the insulating layer 332, for example, a film that is less susceptible to hydrogen or oxygen diffusion than a silicon oxide film can be used, such as an aluminum oxide film, a hafnium oxide film, or a silicon nitride film.

[0273] A conductive layer 327 is provided on an insulating layer 332, and an insulating layer 326 is provided covering the conductive layer 327. The conductive layer 327 functions as the first gate electrode of the transistor 320, and a portion of the insulating layer 326 functions as the first gate insulating layer. It is preferable to use an oxide insulating film, such as a silicon oxide film, for at least the portion of the insulating layer 326 that is in contact with the semiconductor layer 321. It is preferable that the upper surface of the insulating layer 326 is flattened.

[0274] The semiconductor layer 321 is provided on the insulating layer 326. Preferably, the semiconductor layer 321 has a metal oxide (also called an oxide semiconductor) film having semiconductor properties. Details of materials suitable for use in the semiconductor layer 321 will be described later.

[0275] A pair of conductive layers 325 are provided in contact with the semiconductor layer 321 and function as source and drain electrodes.

[0276] Furthermore, an insulating layer 328 is provided covering the top and side surfaces of the pair of conductive layers 325, as well as the side surfaces of the semiconductor layer 321, and an insulating layer 264 is provided on the insulating layer 328. The insulating layer 328 functions as a barrier layer to prevent impurities such as water or hydrogen from diffusing into the semiconductor layer 321 from the insulating layer 264, etc., and to prevent oxygen from detaching from the semiconductor layer 321. As the insulating layer 328, an insulating film similar to that of the insulating layer 332 can be used.

[0277] An opening is provided in the insulating layer 328 and the insulating layer 264 that reaches the semiconductor layer 321. Inside this opening, the insulating layer 323 and the conductive layer 324 are embedded, in contact with the sides of the insulating layer 264, the insulating layer 328, and the conductive layer 325, as well as the upper surface of the semiconductor layer 321. The conductive layer 324 functions as a second gate electrode, and the insulating layer 323 functions as a second gate insulating layer.

[0278] The upper surfaces of the conductive layer 324, the insulating layer 323, and the insulating layer 264 are flattened so that their heights are roughly the same, and the insulating layer 329 and insulating layer 265 are provided covering them.

[0279] Insulating layers 264 and 265 function as interlayer insulating layers. Insulating layer 329 functions as a barrier layer to prevent impurities such as water or hydrogen from diffusing into the transistor 320 from insulating layer 265, etc. As insulating layer 329, an insulating film similar to that used for insulating layers 328 and 332 can be used.

[0280] A plug 274, which is electrically connected to one of the pair of conductive layers 325, is provided so as to be embedded in the insulating layers 265, 329, and 264. Here, it is preferable that the plug 274 has a conductive layer 274a that covers the sides of the openings of the insulating layers 265, 329, 264, and 328, and a part of the upper surface of the conductive layer 325, and a conductive layer 274b that is in contact with the upper surface of the conductive layer 274a. In this case, it is preferable to use a conductive material that does not easily allow hydrogen and oxygen to diffuse as the conductive layer 274a.

[0281] The configuration from the insulating layer 254 to the substrate 120 in the display device 100C is the same as that of the display device 100B.

[0282] [Display device 100D] The display device 100D shown in Figure 15 has a configuration in which a transistor 310 with a channel formed on a substrate 301 and a transistor 320 containing a metal oxide in the semiconductor layer where the channel is formed are stacked. Note that parts that are the same as those of display devices 100B and 100C may be omitted from the explanation.

[0283] An insulating layer 261 is provided covering the transistor 310, and a conductive layer 251 is provided on the insulating layer 261. An insulating layer 262 is provided covering the conductive layer 251, and a conductive layer 252 is provided on the insulating layer 262. The conductive layers 251 and 252 each function as wiring. An insulating layer 263 and an insulating layer 332 are provided covering the conductive layer 252, and a transistor 320 is provided on the insulating layer 332. An insulating layer 265 is provided covering the transistor 320, and a capacitor 240 is provided on the insulating layer 265. The capacitor 240 and the transistor 320 are electrically connected by a plug 274.

[0284] Transistor 320 can be used as a transistor constituting a pixel circuit. Transistor 310 can also be used as a transistor constituting a pixel circuit, or as a transistor constituting a drive circuit (gate line drive circuit, source line drive circuit) for driving the pixel circuit. Furthermore, transistors 310 and 320 can be used as transistors constituting various circuits such as arithmetic circuits or memory circuits.

[0285] This configuration allows for the formation of not only pixel circuits but also drive circuits directly beneath the light-emitting device, making it possible to miniaturize the display device compared to cases where the drive circuits are located around the display area.

[0286] This embodiment can be combined with other embodiments as appropriate.

[0287] (Embodiment 4) This embodiment describes a light-emitting device that can be used in a display device according to one aspect of the present invention.

[0288] The light-emitting device shown in Figure 16A has an electrode 772, an EL layer 786, and an electrode 788. Of the electrodes 772 and 788, one functions as an anode and the other as a cathode. Furthermore, of the electrodes 772 and 788, one functions as a pixel electrode and the other as a counter electrode. Preferably, of the electrodes 772 and 788, the electrode that extracts light is transparent to visible light, and the other electrode reflects visible light.

[0289] The EL layer 786 of the light-emitting device can be composed of multiple layers, such as layer 4420, light-emitting layer 4411, and layer 4430, as shown in Figure 16A. Layer 4420 may include, for example, a layer containing a material with high electron injection properties (electron injection layer) and a layer containing a material with high electron transport properties (electron transport layer). Light-emitting layer 4411 may contain, for example, a light-emitting compound. Layer 4430 may include, for example, a layer containing a material with high hole injection properties (hole injection layer) and a layer containing a material with high hole transport properties (hole transport layer).

[0290] A configuration having a layer 4420, a light-emitting layer 4411, and a layer 4430 provided between a pair of electrodes can function as a single light-emitting unit, and in this specification, the configuration shown in Figure 16A is referred to as a single structure.

[0291] Further, FIG. 16B shows a modified example of the EL layer 786 included in the light-emitting device shown in FIG. 16A. Specifically, the light-emitting device shown in FIG. 16B includes a layer 4431 on the electrode 772, a layer 4432 on the layer 4431, a light-emitting layer 4411 on the layer 4432, a layer 4421 on the light-emitting layer 4411, a layer 4422 on the layer 4421, and an electrode 788 on the layer 4422. For example, when the electrode 772 is an anode and the electrode 788 is a cathode, the layer 4431 functions as a hole injection layer, the layer 4432 functions as a hole transport layer, the layer 4421 functions as an electron transport layer, and the layer 4422 functions as an electron injection layer. Or, when the electrode 772 is a cathode and the electrode 788 is an anode, the layer 4431 functions as an electron injection layer, the layer 4432 functions as an electron transport layer, the layer 4421 functions as a hole transport layer, and the layer 4422 functions as a hole injection layer. By adopting such a layer structure, carriers can be efficiently injected into the light-emitting layer 4411, and the efficiency of carrier recombination in the light-emitting layer 4411 can be increased.

[0292] In addition, as shown in FIG. 16C, a configuration in which a plurality of light-emitting layers (light-emitting layers 4411, 4412, 4413) are provided between the layer 4420 and the layer 4430 is also a variation of the single structure.

[0293] Further, as shown in FIG. 16D, a configuration in which a plurality of light-emitting units (EL layers 786a, 786b) are connected in series via an intermediate layer 4440 (also referred to as a charge generation layer) is referred to as a tandem structure in this specification. Note that the present invention is not limited to this, and for example, the tandem structure may be referred to as a stack structure. By adopting the tandem structure, a light-emitting device capable of high-luminance emission can be obtained.

[0294] In FIGS. 16C and 16D as well, as shown in FIG. 16B, the layer 4420 and the layer 4430 can each have a stacked structure composed of two or more layers.

[0295] The light-emitting color of the light-emitting device can be red, green, blue, cyan, magenta, yellow, or white, depending on the material that makes up the EL layer 786. Furthermore, the color purity can be further enhanced by adding a microcavity structure to the light-emitting device.

[0296] A light-emitting device that emits white light preferably has a configuration in which two or more light-emitting materials are included in the light-emitting layer. To obtain white light emission, it is sufficient to select light-emitting materials such that the light emitted by each of the two or more materials is complementary in color. For example, by making the light-emitting color of the first light-emitting layer and the light-emitting color of the second light-emitting layer complementary, a light-emitting device that emits white light as a whole can be obtained. The same applies to light-emitting devices that have three or more light-emitting layers. For example, if the light-emitting colors of light-emitting layers 4411, 4412, and 4413 shown in Figure 16C are complementary, a single-structure white light-emitting device can be realized.

[0297] The light-emitting layer preferably contains two or more light-emitting materials that emit light such as R (red), G (green), B (blue), Y (yellow), and O (orange). Alternatively, it is preferable to have two or more light-emitting materials, and for each light-emitting material to emit light that contains spectral components of two or more colors from R, G, and B.

[0298] This embodiment can be combined with other embodiments as appropriate.

[0299] (Embodiment 5) This embodiment describes metal oxides (also called oxide semiconductors) that can be used in the OS transistor described in the above embodiment.

[0300] The metal oxide preferably contains at least indium or zinc. It is particularly preferable that it contains indium and zinc. In addition, it is preferable that it contains aluminum, gallium, yttrium, tin, etc. It may also contain one or more selected from boron, silicon, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, cobalt, etc.

[0301] Furthermore, metal oxides can be formed by methods such as sputtering, chemical vapor deposition (CVD) methods including metal-organic chemical vapor deposition (MOCVD), or atomic layer deposition (ALD).

[0302] <Classification of crystal structures> Examples of crystalline structures for oxide semiconductors include amorphous (including completely amorphous), CAAC (c-axis-aligned crystalline), nc (nanocrystalline), CAC (cloud-aligned composite), single crystal, and polycrystal.

[0303] The crystal structure of a film or substrate can be evaluated using X-ray diffraction (XRD) spectroscopy. For example, it can be evaluated using the XRD spectrum obtained by GIXD (Grazing-Incidence XRD) measurement. The GIXD method is also known as the thin-film method or the Seemann-Bohlin method.

[0304] For example, in a quartz glass substrate, the peak shape of the XRD spectrum is nearly symmetrical. On the other hand, in an IGZO film with a crystalline structure, the peak shape of the XRD spectrum is asymmetrical. The asymmetrical shape of the XRD spectrum peak clearly indicates the presence of crystals in the film or substrate. In other words, if the peak shape of the XRD spectrum is not symmetrical, the film or substrate cannot be said to be in an amorphous state.

[0305] Furthermore, the crystalline structure of a film or substrate can be evaluated by the diffraction pattern (also called the nano-beam electron diffraction pattern) observed using nano-beam electron diffraction (NBED). For example, a halo is observed in the diffraction pattern of a quartz glass substrate, confirming that the quartz glass is in an amorphous state. However, in the diffraction pattern of an IGZO film deposited at room temperature, a spot-like pattern is observed instead of a halo. Therefore, it is presumed that an IGZO film deposited at room temperature is in an intermediate state, neither crystalline nor amorphous, and cannot be concluded to be in an amorphous state.

[0306] <<Oxide semiconductor structure>> It should be noted that oxide semiconductors may be classified differently from those described above when considering their structure. For example, oxide semiconductors can be divided into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors. Examples of non-single-crystal oxide semiconductors include the aforementioned CAAC-OS and nc-OS. Non-single-crystal oxide semiconductors also include polycrystalline oxide semiconductors, pseudo-amorphous oxide semiconductors (a-like OS), and amorphous oxide semiconductors.

[0307] Here, we will explain the details of the CAAC-OS, nc-OS, and a-like OS mentioned above.

[0308] [CAAC-OS] CAAC-OS is an oxide semiconductor having multiple crystalline regions, the c-axis of which is oriented in a specific direction. This specific direction is the thickness direction of the CAAC-OS film, the normal direction to the surface on which the CAAC-OS film is formed, or the normal direction to the surface of the CAAC-OS film. A crystalline region is a region with periodic atomic arrangement. If we consider the atomic arrangement as a lattice arrangement, then a crystalline region is also a region with a aligned lattice arrangement. Furthermore, CAAC-OS has regions where multiple crystalline regions are connected in the ab-plane direction, and these regions may exhibit distortion. Distortion refers to a point in the connected region where the orientation of the lattice arrangement changes between a region with a aligned lattice arrangement and another region with a aligned lattice arrangement. In short, CAAC-OS is an oxide semiconductor that is c-axis oriented and does not exhibit clear orientation in the ab-plane direction.

[0309] Each of the multiple crystalline regions described above is composed of one or more minute crystals (crystals with a maximum diameter of less than 10 nm). When a crystalline region is composed of a single minute crystal, the maximum diameter of that crystalline region is less than 10 nm. When a crystalline region is composed of many minute crystals, the size of that crystalline region may be around several tens of nanometers.

[0310] Furthermore, in In-M-Zn oxides (where element M is one or more elements selected from aluminum, gallium, yttrium, tin, titanium, etc.), CAAC-OS tends to have a layered crystalline structure (also called a layered structure) consisting of layers containing indium (In) and oxygen (hereinafter referred to as the In layer) and layers containing element M, zinc (Zn), and oxygen (hereinafter referred to as the (M,Zn) layer). Note that indium and element M are mutually substitutable. Therefore, the (M,Zn) layer may contain indium. Also, the In layer may contain element M. Also, the In layer may contain Zn. This layered structure can be observed, for example, as a lattice image in high-resolution TEM (Transmission Electron Microscope) images.

[0311] When structural analysis of a CAAC-OS film is performed using an XRD instrument, for example, out-of-plane XRD measurements using θ / 2θ scanning show a peak indicating c-axis orientation at 2θ = 31° or nearby. Note that the position of the c-axis orientation peak (value of 2θ) may vary depending on the type and composition of the metal elements constituting the CAAC-OS.

[0312] Furthermore, for example, multiple bright spots are observed in the electron diffraction pattern of a CAAC-OS film. These spots are observed at point-symmetric positions with respect to the incident electron beam spot (also called the direct spot) that passed through the sample.

[0313] When the crystal region is observed from the specific direction described above, the lattice arrangement within that crystal region is based on a hexagonal lattice, but the unit cell is not necessarily a regular hexagon and may be non-regular hexagonal. Furthermore, the strain may have lattice arrangements such as pentagons or heptagons. Moreover, in CAAC-OS, clear grain boundaries cannot be observed even near the strain. In other words, it can be seen that the formation of grain boundaries is suppressed by the strain in the lattice arrangement. This is thought to be because CAAC-OS can tolerate strain due to the fact that the arrangement of oxygen atoms is not dense in the ab-plane direction, and the bond distance between atoms changes due to the substitution of metal atoms.

[0314] A crystal structure in which clear grain boundaries are observed is called a polycrystal. Grain boundaries act as recombination centers, trapping carriers and potentially causing a decrease in transistor on-current and field-effect mobility. Therefore, CAAC-OS, in which clear grain boundaries are not observed, is one of the crystalline oxides with a suitable crystal structure for the semiconductor layer of a transistor. In addition, a structure containing Zn is preferred for the composition of CAAC-OS. For example, In-Zn oxide and In-Ga-Zn oxide are preferred because they suppress the generation of grain boundaries more than In oxide.

[0315] CAAC-OS is an oxide semiconductor with high crystallinity and no clearly defined grain boundaries. Therefore, CAAC-OS is less susceptible to the decrease in electron mobility caused by grain boundaries. Furthermore, since the crystallinity of oxide semiconductors can decrease due to the inclusion of impurities and the generation of defects, CAAC-OS can be said to be an oxide semiconductor with few impurities and defects (such as oxygen vacancies). Consequently, oxide semiconductors containing CAAC-OS have stable physical properties. Therefore, oxide semiconductors containing CAAC-OS are heat resistant and highly reliable. In addition, CAAC-OS is stable even at high temperatures (so-called thermal budget) during the manufacturing process. Therefore, using CAAC-OS in OS transistors allows for greater flexibility in the manufacturing process.

[0316] [nc-OS] nc-OS exhibits periodicity in atomic arrangement in minute regions (e.g., regions between 1 nm and 10 nm, particularly between 1 nm and 3 nm). In other words, nc-OS contains minute crystals. These minute crystals are also called nanocrystals because their size is, for example, between 1 nm and 10 nm, particularly between 1 nm and 3 nm. Furthermore, nc-OS shows no regularity in crystal orientation between different nanocrystals. Therefore, no orientation is observed throughout the film. Consequently, depending on the analytical method, nc-OS may be indistinguishable from a-like OS or amorphous oxide semiconductors. For example, when structural analysis of an nc-OS film is performed using an XRD instrument, no peaks indicating crystallinity are detected in out-of-plane XRD measurements using θ / 2θ scanning. Also, when electron diffraction (also called limited-field electron diffraction) is performed on an nc-OS film using an electron beam with a probe diameter larger than that of the nanocrystals (e.g., 50 nm or larger), a diffraction pattern resembling a halo pattern is observed. On the other hand, when electron diffraction (also called nanobeam electron diffraction) is performed on an nc-OS film using an electron beam with a probe diameter close to or smaller than the size of the nanocrystal (for example, 1 nm to 30 nm), an electron diffraction pattern may be obtained in which multiple spots are observed within a ring-shaped region centered on a direct spot.

[0317] [a-like OS] a-like OS is an oxide semiconductor having a structure between nc-OS and amorphous oxide semiconductors. a-like OS has porous or low-density regions. That is, a-like OS has lower crystallinity compared to nc-OS and CAAC-OS. Also, a-like OS has a higher hydrogen concentration in the film compared to nc-OS and CAAC-OS.

[0318] <<Oxide Semiconductor Composition>> Next, we will explain the details of CAC-OS mentioned above. Note that CAC-OS refers to the material composition.

[0319] [CAC-OS] CAC-OS is a material composition in which, for example, the elements constituting the metal oxide are unevenly distributed in sizes of 0.5 nm to 10 nm, preferably 1 nm to 3 nm, or close to that size. In the following, a state in which one or more metal elements are unevenly distributed in a metal oxide, and the regions containing these metal elements are mixed in sizes of 0.5 nm to 10 nm, preferably 1 nm to 3 nm, or close to that size, is also referred to as a mosaic or patchy state.

[0320] Furthermore, CAC-OS is a composite metal oxide having a mosaic-like structure formed by the separation of the material into a first region and a second region, with the first region distributed within the film (hereinafter also referred to as a cloud-like structure). In other words, CAC-OS is a composite metal oxide having a structure in which the first region and the second region are mixed.

[0321] Here, the atomic ratios of In, Ga, and Zn to the metal elements constituting CAC-OS in In-Ga-Zn oxide are denoted as [In], [Ga], and [Zn], respectively. For example, in CAC-OS in In-Ga-Zn oxide, the first region is the region where [In] is greater than the [In] in the composition of CAC-OS. The second region is the region where [Ga] is greater than the [Ga] in the composition of CAC-OS. Alternatively, for example, the first region is the region where [In] is greater than the [In] in the second region, and [Ga] is smaller than the [Ga] in the second region. The second region is the region where [Ga] is greater than the [Ga] in the first region, and [In] is smaller than the [In] in the first region.

[0322] Specifically, the first region described above is a region whose main components are indium oxide, indium zinc oxide, etc. The second region described above is a region whose main components are gallium oxide, gallium zinc oxide, etc. In other words, the first region can be rephrased as a region whose main component is In. Similarly, the second region can be rephrased as a region whose main component is Ga.

[0323] Furthermore, a clear boundary may not be observed between the first region and the second region described above.

[0324] Furthermore, CAC-OS in In-Ga-Zn oxide refers to a material composition containing In, Ga, Zn, and O, in which regions with Ga as the main component and regions with In as the main component are arranged in a mosaic-like manner, with these regions existing randomly. Therefore, it is presumed that CAC-OS has a structure in which metal elements are unevenly distributed.

[0325] CAC-OS can be formed, for example, by sputtering under conditions where the substrate is not heated. When forming CAC-OS by sputtering, one or more gases selected from inert gases (typically argon), oxygen gas, and nitrogen gas may be used as the film-forming gas. Furthermore, it is preferable that the ratio of the oxygen gas flow rate to the total flow rate of the film-forming gas during film formation be as low as possible. For example, it is preferable that the ratio of the oxygen gas flow rate to the total flow rate of the film-forming gas during film formation be 0% or more and less than 30%, preferably 0% or more and 10% or less.

[0326] Furthermore, for example, in the case of CAC-OS in In-Ga-Zn oxide, EDX mapping obtained using energy dispersive X-ray spectroscopy (EDX) confirms that it has a structure in which regions mainly composed of In (first region) and regions mainly composed of Ga (second region) are unevenly distributed and mixed.

[0327] Here, the first region is a region with higher conductivity compared to the second region. In other words, the conductivity of the metal oxide is exhibited when carriers flow through the first region. Therefore, a high field-effect mobility (μ) can be achieved when the first region is distributed in a cloud-like manner within the metal oxide.

[0328] On the other hand, the second region is a region with higher insulating properties compared to the first region. In other words, the distribution of the second region within the metal oxide can suppress leakage current.

[0329] Therefore, when using CAC-OS in a transistor, the conductivity caused by the first region and the insulating property caused by the second region act complementarily to endow CAC-OS with the function of switching (the function of turning on / off). That is, CAC-OS has a conductive function in a part of the material and an insulating function in a part of the material, and has a function as a semiconductor in the whole material. By separating the conductive function and the insulating function, both functions can be enhanced to the maximum extent. Therefore, by using CAC-OS in a transistor, a high on-current (I on )、high field-effect mobility (μ), and good switching operation can be realized.

[0330] In addition, a transistor using CAC-OS has high reliability. Therefore, CAC-OS is optimal for various semiconductor devices including display devices.

[0331] Oxide semiconductors have various structures and each has different characteristics. The oxide semiconductor according to one aspect of the present invention may have two or more of amorphous oxide semiconductors, polycrystalline oxide semiconductors, a-like OS, CAC-OS, nc-OS, and CAAC-OS.

[0332] <Transistor having an oxide semiconductor> Subsequently, the case of using the above oxide semiconductor in a transistor will be described.

[0333] By using the above oxide semiconductor in a transistor, a transistor with high field-effect mobility can be realized. In addition, a highly reliable transistor can be realized.

[0334] It is preferable to use an oxide semiconductor with a low carrier concentration in the transistor. For example, the carrier concentration of the oxide semiconductor is 1×10 17 cm -3 or less, preferably 1×10 15 cm -3 or less, more preferably 1×10 13 cm -3More preferably 1 × 10 11 cm -3 More preferably 1 × 10 10 cm -3 It is less than 1 × 10 -9 cm -3 This concludes the explanation. Furthermore, when lowering the carrier concentration of an oxide semiconductor film, the impurity concentration in the oxide semiconductor film should be lowered to reduce the defect level density. In this specification, a low impurity concentration and low defect level density are referred to as high-purity intrinsic or substantially high-purity intrinsic. Note that oxide semiconductors with low carrier concentrations are sometimes referred to as high-purity intrinsic or substantially high-purity intrinsic oxide semiconductors.

[0335] Furthermore, oxide semiconductor films that are highly intrinsic or substantially highly intrinsic may have a low trap level density due to their low defect level density.

[0336] Furthermore, charges trapped in the trap levels of oxide semiconductors can take a long time to disappear, sometimes behaving like fixed charges. Therefore, transistors in which channel formation regions are formed in oxide semiconductors with a high trap level density may exhibit unstable electrical properties.

[0337] Therefore, reducing the impurity concentration in the oxide semiconductor is effective in stabilizing the electrical characteristics of the transistor. Furthermore, in order to reduce the impurity concentration in the oxide semiconductor, it is preferable to also reduce the impurity concentration in adjacent films. Examples of impurities include hydrogen, nitrogen, alkali metals, alkaline earth metals, iron, nickel, and silicon.

[0338] <Impurities> Here, we will explain the effects of various impurities in oxide semiconductors.

[0339] In oxide semiconductors, the presence of silicon or carbon, which are Group 14 elements, leads to the formation of defect levels in the oxide semiconductor. Therefore, the concentration of silicon or carbon in the oxide semiconductor and the concentration of silicon or carbon near the interface with the oxide semiconductor (concentration obtained by secondary ion mass spectrometry (SIMS)) are compared by 2 × 10⁻⁶. 18 atoms / cm 3 The following is preferably 2 × 10 17 atoms / cm 3 The following applies:

[0340] Furthermore, if an oxide semiconductor contains alkali metals or alkaline earth metals, it may form defect levels and generate carriers. Therefore, transistors using oxide semiconductors containing alkali metals or alkaline earth metals tend to exhibit normally-on characteristics. For this reason, the concentration of alkali metals or alkaline earth metals in the oxide semiconductor obtained by SIMS should be set to 1 × 10⁻⁶. 18 atoms / cm 3 The following is preferably 2 × 10 16 atoms / cm 3 Do the following:

[0341] Furthermore, in oxide semiconductors, the presence of nitrogen generates electrons, which act as carriers, increasing the carrier concentration and making it easier for the semiconductor to become n-type. As a result, transistors using oxide semiconductors containing nitrogen tend to exhibit normally-on characteristics. Alternatively, the presence of nitrogen in oxide semiconductors can lead to the formation of trap levels. As a result, the electrical properties of the transistor may become unstable. For this reason, the nitrogen concentration in oxide semiconductors obtained by SIMS should be set to 5 × 10⁻⁶. 19 atoms / cm 3 Less than 5 × 10 18 atoms / cm 3 More preferably 1 × 10 18 atoms / cm 3 More preferably 5 × 10 17 atoms / cm 3 Do the following:

[0342] Furthermore, hydrogen contained in oxide semiconductors can react with oxygen bonded to metal atoms to form water, potentially creating oxygen vacancies. Hydrogen can then fill these vacancies, generating electrons, which act as carriers. Additionally, some of the hydrogen can combine with oxygen bonded to metal atoms to generate electrons. Therefore, transistors using oxide semiconductors containing hydrogen tend to exhibit normally-on characteristics. For this reason, it is preferable to reduce the hydrogen content in oxide semiconductors as much as possible. Specifically, in oxide semiconductors, the hydrogen concentration obtained by SIMS should be 1 × 10⁻⁶. 20 atoms / cm 3 Less than 1 × 10 19 atoms / cm 3 Less than 5x10 18 atoms / cm 3 Less than 1 × 10 18 atoms / cm 3 Make it less than.

[0343] By using an oxide semiconductor with sufficiently reduced impurities in the channel formation region of a transistor, stable electrical characteristics can be provided.

[0344] This embodiment can be combined with other embodiments as appropriate.

[0345] (Embodiment 6) In this embodiment, an electronic device according to one aspect of the present invention will be described with reference to Figures 17 to 21.

[0346] The electronic device of this embodiment has a display device according to one aspect of the present invention in its display unit. The display device according to one aspect of the present invention is easily made high-definition and high-resolution. Therefore, it can be used in the display units of various electronic devices.

[0347] Examples of electronic devices include television sets, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as other electronic devices with relatively large screens, digital cameras, digital video cameras, digital photo frames, mobile phones, portable game consoles, personal digital assistants, and audio playback devices.

[0348] In particular, a display device according to one aspect of the present invention can be used suitably in electronic devices having a relatively small display area because it can increase the resolution. Examples of such electronic devices include wristwatch-type and bracelet-type information terminals (wearable devices), as well as wearable devices that can be worn on the head, such as VR devices such as head-mounted displays, AR devices such as glasses, and MR devices.

[0349] A display device according to one aspect of the present invention preferably has an extremely high resolution such as HD (1280 x 720 pixels), FHD (1920 x 1080 pixels), WQHD (2560 x 1440 pixels), WQXGA (2560 x 1600 pixels), 4K (3840 x 2160 pixels), or 8K (7680 x 4320 pixels). In particular, a resolution of 4K, 8K, or higher is preferred. Furthermore, the pixel density (resolution) of the display device according to one aspect of the present invention is preferably 100 ppi or more, preferably 300 ppi or more, more preferably 500 ppi or more, more preferably 1000 ppi or more, more preferably 2000 ppi or more, more preferably 3000 ppi or more, more preferably 5000 ppi or more, and even more preferably 7000 ppi or more. By using a display device that has either high resolution or high detail, or both, it becomes possible to further enhance the sense of presence and depth in personal electronic devices such as portable or home-use devices. Furthermore, there are no particular limitations on the screen ratio (aspect ratio) of the display device according to one embodiment of the present invention. For example, the display device can support various screen ratios such as 1:1 (square), 4:3, 16:9, and 16:10.

[0350] The electronic device of this embodiment may have sensors (including those with the function of measuring force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation).

[0351] The electronic device of this embodiment can have a variety of functions. For example, it can have a function to display various information (still images, videos, text images, etc.) on the display unit, a touch panel function, a function to display a calendar, date or time, a function to execute various software (programs), a wireless communication function, a function to read programs or data recorded on a recording medium, and so on.

[0352] Figures 17A, 17B, 18A, and 18B illustrate an example of a wearable device that can be worn on the head. These wearable devices have the function of displaying AR content, or the function of displaying VR content, or both. In addition to AR and VR, these wearable devices may also have the function of displaying SR or MR content. By having electronic devices that can display AR, VR, SR, MR, etc., it is possible to enhance the user's sense of immersion.

[0353] The electronic device 700A shown in Figure 17A and the electronic device 700B shown in Figure 17B each include a pair of display panels 751, a pair of housings 721, a communication unit (not shown), a pair of mounting units 723, a control unit (not shown), an imaging unit (not shown), a pair of optical members 753, a frame 757, and a pair of nose pads 758.

[0354] A display device according to one aspect of the present invention can be applied to the display panel 751. Therefore, an electronic device capable of displaying extremely high resolution can be created.

[0355] Electronic devices 700A and 700B can project an image displayed on the display panel 751 onto the display area 756 of the optical element 753. Because the optical element 753 is translucent, the user can see the image displayed on the display area superimposed on the transmitted image visible through the optical element 753. Therefore, electronic devices 700A and 700B are electronic devices capable of AR display.

[0356] Electronic devices 700A and 700B may be equipped with cameras capable of capturing images of the area in front of them as imaging units. Furthermore, electronic devices 700A and 700B may each be equipped with acceleration sensors such as gyro sensors to detect the orientation of the user's head and display an image corresponding to that orientation in the display area 756.

[0357] The communications unit has a wireless communication device, which can supply video signals and the like. Alternatively, instead of the wireless communication device, or in addition to the wireless communication device, it may be equipped with a connector to which a cable supplying video signals and power potential can be connected.

[0358] Furthermore, electronic devices 700A and 700B are equipped with batteries that can be charged wirelessly, wired, or both.

[0359] The housing 721 may be equipped with a touch sensor module. The touch sensor module has the function of detecting when the outer surface of the housing 721 is touched. The touch sensor module can detect the user's tap or slide operations and perform various processes. For example, a tap operation can be used to pause or resume the video, and a slide operation can be used to fast forward or rewind. Furthermore, by providing a touch sensor module in each of the two housings 721, the range of operations can be expanded.

[0360] Various types of touch sensors can be applied to the touch sensor module. For example, various methods such as capacitive, resistive, infrared, electromagnetic induction, surface acoustic wave, and optical sensors can be used. In particular, it is preferable to apply a capacitive or optical sensor to the touch sensor module.

[0361] When using an optical touch sensor, a photoelectric conversion device (also called a photoelectric element) can be used as the light-receiving device (also called a photoelectric element). The active layer of the photoelectric conversion device can be made of either an inorganic semiconductor or an organic semiconductor, or both.

[0362] The electronic device 800A shown in Figure 18A and the electronic device 800B shown in Figure 18B each include a pair of display units 820, a housing 821, a communication unit 822, a pair of mounting units 823, a control unit 824, a pair of imaging units 825, and a pair of lenses 832.

[0363] A display device according to one embodiment of the present invention can be applied to the display unit 820. Therefore, an electronic device capable of displaying extremely high resolution can be created. This allows the user to experience a high level of immersion.

[0364] The display unit 820 is located inside the housing 821, in a position where it can be seen through the lens 832. Furthermore, by displaying different images on a pair of display units 820, a three-dimensional display using parallax can also be performed.

[0365] Electronic devices 800A and 800B can be described as electronic devices for VR. A user wearing either electronic device 800A or electronic device 800B can view the image displayed on the display unit 820 through the lens 832.

[0366] It is preferable that electronic devices 800A and 800B each have a mechanism that allows adjustment of the left and right positions of the lens 832 and the display unit 820 so that they are in the optimal position according to the user's eye position. It is also preferable that they have a mechanism that adjusts the focus by changing the distance between the lens 832 and the display unit 820.

[0367] The attachment portion 823 allows the user to attach the electronic device 800A or 800B to their head. While Figure 18A and other figures illustrate the attachment portion as resembling the temples (or joints) of eyeglasses, it is not limited to this shape. The attachment portion 823 only needs to be wearable by the user; for example, it may be helmet-shaped or band-shaped.

[0368] The imaging unit 825 has the function of acquiring external information. The data acquired by the imaging unit 825 can be output to the display unit 820. An image sensor can be used in the imaging unit 825. In addition, multiple cameras may be provided to accommodate multiple angles of view, such as telephoto and wide-angle.

[0369] Although an example with an imaging unit 825 is shown here, any distance measuring sensor (hereinafter also referred to as a detection unit) capable of measuring the distance to an object can be provided. In other words, the imaging unit 825 is one form of a detection unit. As the detection unit, for example, an image sensor or a distance image sensor such as LiDAR (Light Detection and Ranging) can be used. By using the image obtained by the camera and the image obtained by the distance image sensor, more information can be acquired, enabling more accurate gesture control.

[0370] The electronic device 800A may have a vibration mechanism that functions as a bone conduction earphone. For example, a configuration having such a vibration mechanism can be applied to one or more of the display unit 820, housing 821, and mounting unit 823. This allows users to enjoy video and audio simply by wearing the electronic device 800A, without needing separate audio equipment such as headphones, earphones, or speakers.

[0371] Electronic devices 800A and 800B may each have input terminals. Cables can be connected to the input terminals to supply video signals from video output devices, etc., and power for charging batteries provided within the electronic devices.

[0372] An electronic device according to one aspect of the present invention may have a function for wireless communication with an earphone 750. The earphone 750 has a communication unit (not shown) and has a wireless communication function. The earphone 750 can receive information (e.g., voice data) from the electronic device through its wireless communication function. For example, the electronic device 700A shown in Figure 17A has a function for transmitting information to the earphone 750 through its wireless communication function. Also, for example, the electronic device 800A shown in Figure 18A has a function for transmitting information to the earphone 750 through its wireless communication function.

[0373] Furthermore, the electronic device may have an earphone section. The electronic device 700B shown in Figure 17B has an earphone section 727. For example, the earphone section 727 and the control section can be connected to each other by a wire. Part of the wiring connecting the earphone section 727 and the control section may be located inside the housing 721 or the mounting section 723.

[0374] Similarly, the electronic device 800B shown in Figure 18B has an earphone unit 827. For example, the earphone unit 827 and the control unit 824 can be connected to each other by a wire. Part of the wiring connecting the earphone unit 827 and the control unit 824 may be located inside the housing 821 or the mounting unit 823. Also, the earphone unit 827 and the mounting unit 823 may have magnets. This allows the earphone unit 827 to be fixed to the mounting unit 823 by magnetic force, which is preferable as it facilitates storage.

[0375] Furthermore, the electronic device may have an audio output terminal to which earphones or headphones can be connected. The electronic device may also have an audio input terminal and / or an audio input mechanism. For example, a sound-collecting device such as a microphone can be used as the audio input mechanism. By having an audio input mechanism, the electronic device may be given the function of a so-called headset.

[0376] Thus, as one embodiment of the present invention, both eyeglass-type (electronic devices 700A and 700B, etc.) and goggle-type (electronic devices 800A and 800B, etc.) are preferred as electronic devices.

[0377] Furthermore, an electronic device according to one aspect of the present invention can transmit information to earphones via wired or wireless means.

[0378] The electronic device 6500 shown in Figure 19A is a portable information terminal that can be used as a smartphone.

[0379] The electronic device 6500 includes a housing 6501, a display unit 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, and a light source 6508, etc. The display unit 6502 has a touch panel function.

[0380] A display device according to one aspect of the present invention can be applied to the display unit 6502.

[0381] Figure 19B is a schematic cross-sectional view of the housing 6501, including the end on the microphone 6506 side.

[0382] A light-transmitting protective member 6510 is provided on the display side of the housing 6501, and the display panel 6511, optical member 6512, touch sensor panel 6513, printed circuit board 6517, battery 6518, etc. are arranged in the space enclosed by the housing 6501 and the protective member 6510.

[0383] The protective member 6510 is fixed to the display panel 6511, the optical member 6512, and the touch sensor panel 6513 by an adhesive layer (not shown).

[0384] In the area outside the display unit 6502, a portion of the display panel 6511 is folded back, and the FPC 6515 is connected to this folded portion. IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to terminals provided on the printed circuit board 6517.

[0385] A flexible display according to one embodiment of the present invention can be applied to the display panel 6511. This makes it possible to realize an extremely lightweight electronic device. Furthermore, because the display panel 6511 is extremely thin, it is possible to incorporate a large-capacity battery 6518 while keeping the thickness of the electronic device low. In addition, by folding back a part of the display panel 6511 and placing the connection part with the FPC 6515 on the back of the pixel area, it is possible to realize an electronic device with a narrow bezel.

[0386] Figure 20A shows an example of a television system. The television system 7100 has a display unit 7000 incorporated into a housing 7101. Here, the housing 7101 is shown supported by a stand 7103.

[0387] A display device according to one embodiment of the present invention can be applied to the display unit 7000.

[0388] The television device 7100 shown in Figure 20A can be operated using the operation switches on the housing 7101 and a separate remote control unit 7111. Alternatively, the display unit 7000 may be equipped with a touch sensor, and the television device 7100 can be operated by touching the display unit 7000 with a finger or the like. The remote control unit 7111 may have a display unit that displays information output from the remote control unit 7111. Channels and volume can be controlled and the image displayed on the display unit 7000 can be controlled using the operation keys or touch panel on the remote control unit 7111.

[0389] The television system 7100 is configured to include a receiver and a modem. The receiver can receive general television broadcasts. Furthermore, by connecting to a wired or wireless communication network via the modem, it is possible to perform one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication.

[0390] Figure 20B shows an example of a notebook personal computer. The notebook personal computer 7200 has a casing 7211, a keyboard 7212, a pointing device 7213, an external connection port 7214, etc. A display unit 7000 is incorporated into the casing 7211.

[0391] A display device according to one embodiment of the present invention can be applied to the display unit 7000.

[0392] Figures 20C and 20D show examples of digital signage.

[0393] The digital signage 7300 shown in Figure 20C includes a housing 7301, a display unit 7000, and a speaker 7303, etc. Furthermore, it may include LED lamps, operation keys (including a power switch or operation switches), connection terminals, various sensors, a microphone, etc.

[0394] Figure 20D shows a digital signage 7400 mounted on a cylindrical column 7401. The digital signage 7400 has a display unit 7000 that is provided along the curved surface of the column 7401.

[0395] In Figures 20C and 20D, a display device according to one embodiment of the present invention can be applied to the display unit 7000.

[0396] The larger the display area 7000, the more information can be provided at once. Furthermore, a larger display area 7000 is more eye-catching, which can, for example, enhance the effectiveness of advertising.

[0397] Applying a touch panel to the display unit 7000 is preferable because it not only allows images or videos to be displayed on the display unit 7000, but also enables intuitive operation by the user. Furthermore, when used for purposes such as providing route information or traffic information, intuitive operation can enhance usability.

[0398] Furthermore, as shown in Figures 20C and 20D, it is preferable that the digital signage 7300 or digital signage 7400 can be linked wirelessly with an information terminal 7311 or information terminal 7411 such as a smartphone owned by the user. For example, the advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or information terminal 7411. Also, the display on the display unit 7000 can be switched by operating the information terminal 7311 or information terminal 7411.

[0399] Furthermore, the digital signage 7300 or digital signage 7400 can be used to run games using the screen of the information terminal 7311 or information terminal 7411 as the control device (controller). This allows an unspecified number of users to participate in and enjoy the game simultaneously.

[0400] The electronic equipment shown in Figures 21A to 21F includes a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or operation switch), connection terminals 9006, sensors 9007 (including functions for measuring force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation), a microphone 9008, etc.

[0401] In Figures 21A to 21F, a display device according to one embodiment of the present invention can be applied to the display unit 9001.

[0402] The electronic devices shown in Figures 21A to 21F have various functions. For example, they may have functions to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date or time, a function to control processing by various software (programs), a wireless communication function, a function to read and process programs or data recorded on a recording medium, etc. However, the functions of electronic devices are not limited to these and can have various functions. Electronic devices may have multiple display units. Furthermore, electronic devices may be equipped with a camera, etc., and have functions to capture still images or videos and save them to a recording medium (external or built into the camera), a function to display the captured images on a display unit, etc.

[0403] Details of the electronic equipment shown in Figures 21A to 21F will be explained below.

[0404] Figure 21A is a perspective view showing a personal digital assistant (PDA) 9101. The PDA 9101 can be used, for example, as a smartphone. The PDA 9101 may also be equipped with a speaker 9003, connection terminals 9006, sensors 9007, etc. The PDA 9101 can also display text and image information on multiple surfaces. Figure 21A shows an example where three icons 9050 are displayed. Information 9051, indicated by a dashed rectangle, can also be displayed on other surfaces of the display unit 9001. Examples of information 9051 include notifications of incoming emails, SNS (Social Networking Service) messages, and phone calls, as well as the title, sender name, date, time, battery level, and signal strength of emails or SNS messages. Alternatively, icons 9050 may be displayed where the information 9051 is displayed.

[0405] Figure 21B is a perspective view showing the personal digital assistant (PDA) 9102. The PDA 9102 has the function of displaying information on three or more sides of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different sides. For example, a user can check information 9053, which is displayed in a position that can be observed from above the PDA 9102, while the PDA 9102 is stored in the breast pocket of their clothing. The user can check the display without taking the PDA 9102 out of their pocket and decide, for example, whether or not to answer a call.

[0406] Figure 21C is a perspective view showing a wristwatch-type personal information terminal 9200. The personal information terminal 9200 can be used, for example, as a smartwatch (registered trademark). The display unit 9001 has a curved display surface, allowing it to display information along the curved surface. The personal information terminal 9200 can also make hands-free calls by communicating with, for example, a wireless communication headset. Furthermore, the personal information terminal 9200 can transmit data to other information terminals and be charged via a connection terminal 9006. Charging may be performed by wireless power supply.

[0407] Figures 21D to 21F are perspective views showing a foldable portable information terminal 9201. Figure 21D shows the portable information terminal 9201 in an unfolded state, Figure 21F shows it in a folded state, and Figure 21E shows a perspective view of the state in between Figures 21D and 21F. The portable information terminal 9201 offers excellent portability in its folded state and excellent readability of the display due to its seamless, wide display area in its unfolded state. The display unit 9001 of the portable information terminal 9201 is supported by three housings 9000 connected by hinges 9055. For example, the display unit 9001 can be bent with a radius of curvature of 0.1 mm to 150 mm.

[0408] This embodiment can be combined with other embodiments as appropriate. [Explanation of Symbols]

[0409] 100A: Display device, 100B: Display device, 100C: Display device, 100D: Display device, 100: Display device, 101: Layer containing transistor, 110a: Sub-pixel, 110b: Sub-pixel, 110c: Sub-pixel, 110: Pixel, 111a: Pixel electrode, 111b: Pixel electrode, 111c: Pixel electrode, 113A: First layer, 113a: First layer, 113B: Second layer, 113b: Second layer, 113C: Third layer, 113c: Third layer, 114a: Fourth layer, 114b: Fourth layer, 114c: Fourth layer, 114: Fourth layer, 115a: Counter electrode, 115b: Counter electrode, 115 c: Counter electrode, 115: Counter electrode, 117: Light-shielding layer, 118A: First sacrificial layer, 118a: First sacrificial layer, 118B: Second sacrificial layer, 118b: Second sacrificial layer, 118C: Third sacrificial layer, 118c: Third sacrificial layer, 119: Resin layer, 120: Substrate, 121: Insulating layer, 123: Conductive layer, 126a: Optical adjustment layer, 126b: Optical adjustment layer, 126c: Optical adjustment layer, 130a: Light-emitting device, 130b: Light-emitting device, 130c: Light-emitting device, 131: Protective layer, 132: Protective layer, 133: Void, 134: Conductive layer, 140: Connection part, 142: Adhesive layer, 151: Substrate, 152: Substrate, 162: Display unit, 164: Circuit, 165: Wiring, 166: Conductive layer, 172: FPC, 173: IC, 190a: Resist mask, 190b: Resist mask, 190c: Resist mask, 190d: Resist mask, 190e: Resist mask, 201: Transistor, 204: Connection unit, 205: Transistor, 209: Transistor, 210: Transistor, 211: Insulating layer, 213: Insulating layer, 214: Insulating layer, 215: Insulating layer, 218: Insulating layer, 221: Conductive layer, 222a: Conductive layer, 222b: Conductive layer, 223: Conductive layer, 225: Insulating layer ,228: region, 231i: channel formation region, 231n: low resistance region, 231: semiconductor layer, 240: capacitance, 241: conductive layer, 242: connection layer, 243: insulating layer, 245: conductive layer, 251: conductive layer, 252: conductive layer, 254: insulating layer, 255: insulating layer, 256: plug, 261: insulating layer, 262: insulating layer, 263: insulating layer, 264: insulating layer, 265: insulating layer, 271: plug, 274a: conductive layer, 274b: conductive layer, 274: plug, 280: display module, 281: display unit, 282: circuit unit, 283a: pixel circuit, 283: pixel circuit unit, 284a: pixel,284: Pixel section, 285: Terminal section, 286: Wiring section, 290: FPC, 291: Substrate, 292: Substrate, 301: Substrate, 310: Transistor, 311: Conductive layer, 312: Low-resistance region, 313: Insulating layer, 314: Insulating layer, 315: Element isolation layer, 320: Transistor, 321: Semiconductor layer, 323: Insulating layer, 324: Conductive layer, 325: Conductive layer, 326: Insulating layer, 327: Conductive layer, 328: Insulating layer, 329: Insulating layer, 331: Substrate, 332: Insulating layer, 700A: Electronic equipment, 700B: Electronic equipment, 721: Housing, 723: Mounting section, 727: Earphone section, 750 : Earphone, 751: Display panel, 753: Optical component, 756: Display area, 757: Frame, 758: Nose pad, 772: Electrode, 786a: EL layer, 786b: EL layer, 786: EL layer, 788: Electrode, 800A: Electronic equipment, 800B: Electronic equipment, 820: Display unit, 821: Housing, 822: Communication unit, 823: Mounting unit, 824: Control unit, 825: Imaging unit, 827: Earphone unit, 832: Lens, 4411: Light-emitting layer, 4412: Light-emitting layer, 4413: Light-emitting layer, 4420: Layer, 4421: Layer, 4422: Layer, 4430: Layer, 4431: Layer, 4432: Layer, 4 440: Intermediate layer, 6500: Electronic equipment, 6501: Housing, 6502: Display unit, 6503: Power button, 6504: Button, 6505: Speaker, 6506: Microphone, 6507: Camera, 6508: Light source, 6510: Protective component, 6511: Display panel, 6512: Optical component, 6513: Touch sensor panel, 6515: FPC, 6516: IC, 6517: Printed circuit board, 6518: Battery, 7000: Display unit, 7100: Television equipment, 7101: Housing, 7103: Stand, 7111: Remote control unit, 7200: Notebook personal computer Data, 7211: Enclosure, 7212: Keyboard, 7213: Pointing device, 7214: External connection port, 7300: Digital signage, 7301: Enclosure, 7303: Speaker, 7311: Information terminal, 7400: Digital signage, 7401: Pillar, 7411: Information terminal, 9000: Enclosure, 9001: Display unit, 9003: Speaker, 9005: Operation keys, 9006: Connection terminal, 9007: Sensor, 9008: Microphone, 9050: Icon, 9051: Information, 9052: Information, 9053: Information, 9054: Information, 9055: Hinge,9101: Mobile information terminal, 9102: Mobile information terminal, 9200: Mobile information terminal, 9201: Mobile information terminal,

Claims

1. A first pixel electrode and a second pixel electrode are formed. A first layer is formed on the first pixel electrode and the second pixel electrode. A first sacrificial layer is formed on the first layer described above. The first layer and the first sacrificial layer are processed to expose at least a portion of the second pixel electrode. A second layer is formed on the first pixel electrode and the second pixel electrode. A second sacrificial layer is formed on the second layer described above. The second layer and the second sacrificial layer are processed to expose at least a portion of the first sacrificial layer. Remove the first sacrificial layer and the second sacrificial layer, A third layer is formed on the first pixel electrode and the second pixel electrode. A counter electrode is formed on the third layer, A method for manufacturing a display device, comprising processing the third layer and the counter electrode to remove at least a portion of the third layer and the counter electrode, respectively, that are included in the region between the first pixel electrode and the second pixel electrode in a top view.

2. In claim 1, After processing the third layer and the counter electrode, A method for manufacturing a display device, comprising forming a protective layer on the counter electrode.

3. In claim 2, As the protective layer, a first protective layer is formed by a first film formation method, and a second protective layer is formed by a second film formation method. A method for manufacturing a display device, wherein the first film formation method is a film formation method that forms a film with higher coverage than the second film formation method.

4. In any one of claims 1 to 3, Before forming the first layer, an insulating layer is formed to cover the ends of the first pixel electrode and the ends of the second pixel electrode. A method for manufacturing a display device, wherein at least a portion of the insulating layer is exposed in the process of processing the third layer and the counter electrode.

5. In any one of claims 1 to 4, A first resist mask is formed on the first sacrificial layer, overlapping with the first pixel electrode. When processing the first layer and the first sacrificial layer, the first resist mask is used. A second resist mask is formed on the second sacrificial layer, overlapping with the second pixel electrode. A method for manufacturing a display device, comprising using the second resist mask when processing the second layer and the second sacrificial layer.

6. In any one of claims 1 to 5, A third resist mask is formed on the counter electrode, having an opening in the region between the first pixel electrode and the second pixel electrode in a top view. A method for manufacturing a display device, wherein the third resist mask is used when processing the third layer and the counter electrode.

7. In any one of claims 1 to 5, A third resist mask is formed on the counter electrode, having a first portion that overlaps with the first pixel electrode and a second portion that overlaps with the second pixel electrode, separated from each other. A method for manufacturing a display device, wherein the third resist mask is used when processing the third layer and the counter electrode.

8. A plurality of first pixel electrodes arranged in a first direction and a plurality of second pixel electrodes arranged in the first direction are formed by arranging them in a second direction. A first layer is formed on the plurality of first pixel electrodes and on the plurality of second pixel electrodes. A first sacrificial layer is formed on the first layer described above. The first layer and the first sacrificial layer are processed to expose at least a portion of each of the plurality of second pixel electrodes. A second layer is formed on the plurality of first pixel electrodes and on the plurality of second pixel electrodes. A second sacrificial layer is formed on the second layer described above. The second layer and the second sacrificial layer are processed to expose at least a portion of the first sacrificial layer. Remove the first sacrificial layer and the second sacrificial layer, A third layer is formed on the plurality of first pixel electrodes and on the plurality of second pixel electrodes. A counter electrode is formed on the third layer, The third layer and the counter electrode are processed to remove at least a portion of the third layer and the counter electrode, respectively, that are included in the region between the first pixel electrode and the second pixel electrode in a top view. A protective layer is formed on the opposing electrode. The protective layer is processed to expose at least a portion of the counter electrodes included in the region between the plurality of first pixel electrodes and the region between the plurality of second pixel electrodes in a top view. A method for manufacturing a display device, comprising forming a conductive layer on the counter electrode and on the protective layer.

9. In claim 8, As the protective layer, a first protective layer is formed by a first film formation method, and a second protective layer is formed by a second film formation method. A method for manufacturing a display device, wherein the first film formation method is a film formation method that forms a film with higher coverage than the second film formation method.

10. In claim 8 or 9, Before forming the first layer, an insulating layer is formed to cover the ends of the plurality of first pixel electrodes and the ends of the plurality of second pixel electrodes. A method for manufacturing a display device, wherein at least a portion of the insulating layer is exposed in the process of processing the third layer and the counter electrode.

11. In any one of claims 8 to 10, A first resist mask is formed on the first sacrificial layer, overlapping with the first pixel electrode. When processing the first layer and the first sacrificial layer, the first resist mask is used. A second resist mask is formed on the second sacrificial layer, overlapping with the second pixel electrode. A method for manufacturing a display device, comprising using the second resist mask when processing the second layer and the second sacrificial layer.

12. In any one of claims 8 to 11, A third resist mask is formed on the counter electrode, having an opening in the region between the first pixel electrode and the second pixel electrode in a top view. A method for manufacturing a display device, wherein the third resist mask is used when processing the third layer and the counter electrode.

13. In any one of claims 8 to 11, A third resist mask is formed on the counter electrode, having a first portion that overlaps with the plurality of first pixel electrodes and a second portion that overlaps with the plurality of second pixel electrodes, separated from each other. A method for manufacturing a display device, wherein the third resist mask is used when processing the third layer and the counter electrode.

14. In any one of claims 8 to 13, A fourth resist mask is formed on the protective layer, having openings in the regions between the plurality of first pixel electrodes and the regions between the plurality of second pixel electrodes when viewed from above. A method for manufacturing a display device, wherein the fourth resist mask is used when processing the protective layer.

15. In any one of claims 8 to 13, A fourth resist mask is formed on the protective layer, having a third portion that overlaps with at least one of the plurality of first pixel electrodes and at least one of the plurality of second pixel electrodes, and a fourth portion that overlaps with at least one other of the plurality of first pixel electrodes and at least one other of the plurality of second pixel electrodes, with these portions separated from each other. A method for manufacturing a display device, wherein the fourth resist mask is used when processing the protective layer.

16. Multiple first light-emitting devices and multiple second light-emitting devices, A protective layer on the plurality of first light-emitting devices and on the plurality of second light-emitting devices, The protective layer has a conductive layer, The first light-emitting device comprises a first pixel electrode, a first layer on the first pixel electrode, a third layer on the first layer, and a counter electrode on the third layer. The second light-emitting device comprises a second pixel electrode, a second layer on the second pixel electrode, a third layer on the second layer, and the counter electrode on the third layer. The first light-emitting device and the second light-emitting device have the function of emitting light of different colors from each other. In a top view, the region between the first pixel electrode and the second pixel electrode has a first portion in which the third layer and the counter electrode are not provided. The third layer and the counter electrode are provided across the plurality of first light-emitting devices, The third layer and the counter electrode are provided across the plurality of second light-emitting devices, In a top view, the region between the two first pixel electrodes and the region between the two second pixel electrodes each have a second portion where the protective layer is not provided. A display device in which, in the second part described above, the counter electrode and the conductive layer are electrically connected.

17. In claim 16, A display device having a gap between the first light-emitting device and the second light-emitting device, surrounded by the protective layer.

18. In claim 16, The protective layer comprises a first protective layer on the counter electrode and a second protective layer on the first protective layer. A display device having a gap between the first light-emitting device and the second light-emitting device, surrounded by the first protective layer and the second protective layer.

19. A display device according to any one of claims 16 to 18, A display module having at least one of a connector and an integrated circuit.

20. The display module according to claim 19, An electronic device comprising at least one of a housing, a battery, a camera, a speaker, and a microphone.

Images