Indication device

Abstract

To provide a display device with highly accurate light detection capabilities. [Solution] A display device comprising a light-receiving device, a first light-emitting device, and an insulating layer. The light-receiving device comprises a first electrode, a light-receiving layer, and a common electrode. The first light-emitting device comprises a second electrode, a first EL layer, and a common electrode. The light-receiving layer comprises a first functional layer, a second functional layer, and an active layer between them. The first functional layer contains a first substance having hole-transporting properties. The second functional layer contains a second substance having electron-transporting properties. The edges of the active layer, the edges of the first functional layer, and the edges of the first functional layer coincide or substantially coincide with each other. The first EL layer comprises a third functional layer, a fourth functional layer, and a first light-emitting layer between them. The third functional layer contains a third substance having hole-transporting properties. The fourth functional layer contains a fourth substance having electron-transporting properties. The insulating layer has regions in contact with the sides of the light-receiving layer and the sides of the first EL layer.

Description

Technical Field

[0001] One aspect of the present invention relates to a display device. One aspect of the present invention relates to a method for manufacturing a display device.

[0002] Note that one aspect of the present invention is not limited to the above technical field. As the technical field of one aspect of the present invention disclosed in this specification and the like, semiconductor devices, display devices, light-emitting devices, power storage devices, storage devices, electronic devices, lighting devices, input devices, input / output devices, their driving methods, or their manufacturing methods can be cited as an example. A semiconductor device refers to all devices that can function by utilizing semiconductor characteristics.

Background Art

[0003] In recent years, display devices are used in various devices such as information terminal devices such as smartphones, tablet terminals, and laptop PCs, television devices, and monitor devices. In addition, there is a demand for display devices to which various functions are added, such as a function as a touch sensor or a function of imaging fingerprints for authentication, in addition to displaying images.

[0004] As a display device, for example, a light-emitting device (also referred to as a light-emitting element) having a light-emitting device has been developed. A light-emitting device (also referred to as an EL device or an EL element) that utilizes the electroluminescence (EL) phenomenon has characteristics such as being easily thinned and lightened, being able to respond quickly to an input signal, and being able to be driven using a DC constant voltage power supply, and is applied to display devices. For example, Patent Document 1 discloses a flexible light-emitting device to which an organic EL device (also referred to as an organic EL element) is applied.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

[0006] One aspect of the present invention aims to provide a display device having a light detection function and high resolution. One aspect of the present invention aims to provide a display device having a highly accurate light detection function. One aspect of the present invention aims to provide a display device having a light detection function and low power consumption. One aspect of the present invention aims to provide a highly reliable display device having a light detection function. One aspect of the present invention aims to provide a novel display device.

[0007] Furthermore, the description of these problems does not preclude the existence of other problems. Moreover, one aspect of the present invention does not need to solve all of these problems. Other problems can be identified from the description in the specification, drawings, claims, etc. [Means for solving the problem]

[0008] One aspect of the present invention is a display device having a light-receiving device, a first light-emitting device, and an insulating layer. The light-receiving device has a first electrode, a light-receiving layer, and a common electrode stacked in this order. The first light-emitting device has a second electrode, a first EL layer, and a common electrode stacked in this order. The light-receiving layer has a first functional layer, a second functional layer, and an active layer between the first and second functional layers. The first functional layer contains a first substance having hole-transporting properties. The second functional layer contains a second substance having electron-transporting properties. The edges of the active layer, the edges of the first functional layer, and the edges of the second functional layer coincide or substantially coincide with each other. The first EL layer has a third functional layer, a fourth functional layer, and a first light-emitting layer between the third and fourth functional layers. The third functional layer contains a third substance having hole-transporting properties. The fourth functional layer contains a fourth substance having electron-transporting properties. The insulating layer has regions that are in contact with the side surfaces of the light-receiving layer and the side surfaces of the first EL layer.

[0009] In the aforementioned display device, it is preferable that the first substance is the same as the third substance.

[0010] In the aforementioned display device, it is preferable that the second substance is the same as the fourth substance.

[0011] In the aforementioned display device, it is preferable that the active layer has a fifth substance, and the first light-emitting layer has a sixth substance different from the fifth substance.

[0012] In the aforementioned display device, it is preferable that the side surface of the light-receiving layer is perpendicular or approximately perpendicular to the surface on which the light-receiving layer is formed.

[0013] In the aforementioned display device, it is preferable that the side surface of the first EL layer is perpendicular or approximately perpendicular to the surface on which the first EL layer is formed.

[0014] In the aforementioned display device, it is preferable that the edges of the first light-emitting layer, the third functional layer, and the fourth functional layer coincide or substantially coincide with each other.

[0015] In the aforementioned display device, it is preferable that the film thickness in the region of the first light-emitting layer that is in contact with the insulating layer is thinner than the film thickness in the region of the first light-emitting layer that is not in contact with the insulating layer.

[0016] In the aforementioned display device, it is preferable that the end of the first light-emitting layer is located inward from the end of the third functional layer and the end of the fourth functional layer.

[0017] In the aforementioned display device, it is preferable that the end of the light-receiving layer is located inward from the end of the first electrode. Furthermore, it is preferable that the insulating layer has a region that is in contact with the side surface of the light-receiving layer, as well as the upper surface and side surface of the first electrode.

[0018] In the aforementioned display device, it is preferable that the end of the first EL layer is located inside the end of the second electrode. Furthermore, it is preferable that the insulating layer has a region that is in contact with the side surface of the first EL layer and the top and side surfaces of the second electrode.

[0019] In the aforementioned display device, it is preferable that the active layer has a region that overlaps with the first electrode via the first functional layer.

[0020] In the aforementioned display device, it is preferable that the active layer has a region that overlaps with the first electrode via a second functional layer.

[0021] In the aforementioned display device, it is preferable that the first light-emitting layer has a region that overlaps with the second electrode via the third functional layer.

[0022] In the aforementioned display device, it is preferable that the first light-emitting layer has a region that overlaps with the second electrode via the third functional layer.

[0023] In the aforementioned display device, it is preferable to have a second light-emitting device. The second light-emitting device has a third electrode, a second EL layer, and a common electrode stacked in this order. The second EL layer has a fifth functional layer, a sixth functional layer, and a second light-emitting layer between the fifth and sixth functional layers. The fifth functional layer contains a third substance. The sixth functional layer contains a fourth substance.

[0024] In the aforementioned display device, it is preferable to have a second light-emitting device. The second light-emitting device has a third electrode, a second EL layer, and a common electrode stacked in this order. The second EL layer has a third functional layer, a fourth functional layer, and a second light-emitting layer between the third and fourth functional layers. [Effects of the Invention]

[0025] According to one aspect of the present invention, a display device having a light detection function and high resolution can be provided. According to one aspect of the present invention, a display device having a highly accurate light detection function can be provided. According to one aspect of the present invention, a display device having a light detection function and low power consumption can be provided. According to one aspect of the present invention, a highly reliable display device having a light detection function can be provided. According to one aspect of the present invention, a novel display device can be provided.

[0026] Furthermore, the description of these effects does not preclude the existence of other effects. Moreover, one aspect of the present invention does not necessarily have to possess all of these effects. Other effects can be extracted from the description in the specification, drawings, claims, etc. [Brief explanation of the drawing]

[0027] [Figure 1] Figures 1A to 1D are cross-sectional views showing examples of the configuration of a display device. Figure 1E is a diagram showing an example of an captured image. [Figure 2] Figures 2A to 2D are cross-sectional views showing examples of the configuration of a display device. [Figure 3] Figures 3A and 3B are cross-sectional views showing examples of the configuration of a display device. [Figure 4] Figure 4A is a top view showing an example of the configuration of a display device. Figure 4B is a cross-sectional view showing an example of the configuration of a display device. [Figure 5] Figures 5A to 5D are cross-sectional views showing examples of the configuration of a display device. [Figure 6] Figures 6A to 6C are cross-sectional views showing examples of the configuration of a display device. [Figure 7] Figures 7A to 7C are cross-sectional views showing examples of the configuration of a display device. [Figure 8] Figures 8A to 8C are cross-sectional views showing examples of the configuration of a display device. [Figure 9] Figures 9A to 9C are cross-sectional views showing examples of the configuration of a display device. [Figure 10] Figures 10A to 10C are cross-sectional views showing examples of the configuration of a display device. [Figure 11] Figures 11A to 11C are cross-sectional views showing examples of the configuration of a display device. [Figure 12] Figures 12A to 12C are cross-sectional views showing examples of the configuration of a display device. [Figure 13] Figures 13A to 13C are cross-sectional views showing examples of the configuration of a display device. [Figure 14]Figures 14A to 14C are cross-sectional views showing examples of the configuration of a display device. [Figure 15] Figures 15A to 15C are cross-sectional views showing examples of the configuration of a display device. [Figure 16] Figures 16A to 16C are cross-sectional views showing examples of the configuration of a display device. [Figure 17] Figures 17A to 17C are cross-sectional views showing examples of the configuration of a display device. [Figure 18] Figures 18A to 18E are cross-sectional views showing examples of methods for manufacturing a display device. [Figure 19] Figures 19A to 19D are cross-sectional views showing examples of methods for manufacturing a display device. [Figure 20] Figures 20A to 20E are cross-sectional views showing examples of methods for manufacturing a display device. [Figure 21] Figures 21A to 21D are cross-sectional views showing examples of methods for manufacturing a display device. [Figure 22] Figures 22A and 22B are cross-sectional views showing examples of methods for manufacturing a display device. [Figure 23] Figures 23A to 23D are cross-sectional views showing examples of methods for manufacturing a display device. [Figure 24] Figures 24A to 24D are cross-sectional views showing examples of methods for manufacturing a display device. [Figure 25] Figures 25A to 25E are cross-sectional views showing examples of methods for manufacturing a display device. [Figure 26] Figures 26A and 26B are top views showing examples of the configuration of a display device. [Figure 27] Figures 27A and 27B are perspective views showing an example of a display device. [Figure 28] Figure 28 is a cross-sectional view showing an example of a display device. [Figure 29] Figure 29 is a cross-sectional view showing an example of a display device. [Figure 30] Figure 30 is a cross-sectional view showing an example of a display device. [Figure 31] Figure 31 is a cross-sectional view showing an example of a display device. [Figure 32]Figure 32 is a cross-sectional view showing an example of a display device. [Figure 33] Figure 33 is a cross-sectional view showing an example of a display device. [Figure 34] Figure 34 is a perspective view showing an example of a display device. [Figure 35] Figure 35A is a cross-sectional view showing an example of a display device. Figures 35B and 35C are cross-sectional views showing an example of a transistor. [Figure 36] Figure 36 is a cross-sectional view showing an example of a display device. [Figure 37] Figures 37A to 37D are cross-sectional views showing examples of the configuration of a light-emitting device. [Figure 38] Figures 38A to 38G are cross-sectional views showing examples of the configuration of light-receiving and light-emitting devices. [Figure 39] Figures 39A to 39E show examples of electronic devices. [Modes for carrying out the invention]

[0028] The embodiments will be described below with reference to the drawings. However, it will be readily apparent to those skilled in the art that the embodiments can be implemented in many different ways, and their form and details can be modified in various ways without departing from the spirit and scope thereof. Accordingly, the present invention shall not be construed as being limited to the contents of the following embodiments.

[0029] In the configuration of 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 hatch patterns are the same, and reference numerals may not be assigned.

[0030] In the figures described herein, the size of each component, the thickness of the layer, or the area may be exaggerated for clarity. Therefore, the scale is not necessarily limited.

[0031] In this specification, ordinal numbers such as "the first," "the second," etc., are used to avoid confusion of constituent elements and do not imply any numerical limitation.

[0032] In this specification, the terms "film" and "layer" are interchangeable. For example, the terms "conductive layer" or "insulating layer" may be interchangeable with the terms "conductive film" or "insulating film."

[0033] In this specification, the term "EL layer" refers to a layer (also called a light-emitting layer) provided between a pair of electrodes of a light-emitting device and containing at least a light-emitting substance, or a laminate containing a light-emitting layer.

[0034] In this specification, a display panel, which is one form of a display device, has the function of displaying (outputting) images or the like on its display surface. Therefore, a display panel is one form of an output device.

[0035] In this specification, a display panel on which a connector such as an FPC (Flexible Printed Circuit) or TCP (Tape Carrier Package) is attached, or on which an IC is mounted on the board using a COG (Chip On Glass) method, may be referred to as a display panel module, a display module, or simply a display panel, etc.

[0036] (Embodiment 1) This embodiment describes a display device according to one aspect of the present invention.

[0037] A display device according to one aspect of the present invention has a display unit, the display unit having a plurality of pixels arranged in a matrix. Each pixel has a light-emitting device and a light-receiving device (also called a light-receiving element). The light-emitting device functions as a display device (also called a display element). In one aspect of the present invention, the display unit has light-emitting devices arranged in a matrix, and can display an image on the display unit. Furthermore, in one aspect of the present invention, the display device has a function of detecting light using the light-receiving device.

[0038] In one embodiment of the present invention, the display unit of the display device has light-receiving devices arranged in a matrix, and the display unit has an image display function, as well as one or both of an imaging function and a sensing function. The display unit can be used as an image sensor or a touch sensor. That is, by detecting light with the display unit, it is possible to capture an image or detect the proximity or contact of an object (such as a finger, hand, or pen). Furthermore, in one embodiment of the present invention, the light-emitting device can be used as the light source of the sensor. Therefore, it is not necessary to provide a separate light-receiving unit and light source from the display device, and the number of components in the electronic device can be reduced.

[0039] When a light-receiving device is used as an image sensor, the display device can capture an image using the light-receiving device. For example, the display device of this embodiment can be used as a scanner.

[0040] For example, an image sensor can be used to acquire biometric data such as fingerprints and palm prints. In other words, a biometric authentication sensor can be built into the display device. By integrating the biometric authentication sensor into the display device, the number of components in the electronic device can be reduced compared to when a separate biometric authentication sensor is provided, resulting in a smaller and lighter electronic device.

[0041] When a light-receiving device is used as a touch sensor, the display device can use the light-receiving device to detect the proximity or contact of an object.

[0042] In this specification, devices fabricated using a metal mask or FMM (Fine Metal Mask, a high-resolution metal mask) may be referred to as MM (Metal Mask) structured devices. In addition, in this specification, devices fabricated without using a metal mask or FMM may be referred to as MML (Metal Maskless) structured devices.

[0043] The following sections will explain more specific examples using diagrams.

[0044] <Configuration Example 1> Figures 1A to 1D show cross-sectional views illustrating an example of the configuration of a display device according to one aspect of the present invention.

[0045] The display device 100 shown in Figure 1A has a layer 53 having a light-receiving device and a layer 57 having a light-emitting device between substrate 50 and substrate 59.

[0046] Figure 1A shows a configuration in which red (R), green (G), and blue (B) light is emitted from a layer 57 containing a light-emitting device, and the light is incident on a layer 53 containing a light-receiving device. In Figure 1A, the light emitted from layer 57 and the light incident on layer 53 are indicated by arrows, respectively.

[0047] In this specification, the wavelength range for blue (B) is 400 nm or more and less than 490 nm, and blue (B) light has at least one emission spectral peak in this wavelength range. The wavelength range for green (G) is 490 nm or more and less than 580 nm, and green (G) light has at least one emission spectral peak in this wavelength range. The wavelength range for red (R) is 580 nm or more and less than 700 nm, and red (R) light has at least one emission spectral peak in this wavelength range. In this specification, the wavelength range for visible light is 400 nm or more and less than 700 nm, and visible light has at least one emission spectral peak in this wavelength range. The wavelength range for infrared (IR) is 700 nm or more and less than 900 nm, and infrared (IR) light has at least one emission spectral peak in this wavelength range.

[0048] A display device according to one aspect of the present invention is provided on a display unit with a plurality of pixels arranged in a matrix. Each pixel has one or more subpixels. Each subpixel has a light-emitting device or a light-receiving device. For example, a pixel can be configured to have four subpixels. Specifically, one pixel can be configured to have a subpixel having a light-emitting device that emits red (R) light, a subpixel having a light-emitting device that emits green (G) light, a subpixel having a light-emitting device that emits blue (B) light, and a subpixel having a light-receiving device. The light-receiving device is preferably sensitive to the wavelength range of visible light. Alternatively, the light-receiving device is preferably sensitive to the wavelength range of visible light and infrared light.

[0049] Furthermore, the combination of light colors emitted by the light-emitting device of a pixel is not limited to the three colors of red (R), green (G), and blue (B). For example, the combination of light colors emitted by the light-emitting device of a pixel could be yellow (Y), cyan (C), and magenta (M). Moreover, the light colors emitted by the light-emitting device of a pixel may be four or more.

[0050] A pixel may have a configuration that includes five or more subpixels. Specifically, one pixel may have a configuration that includes four types of light-emitting devices: red (R), green (G), blue (B), and white (W), and a light-receiving device. Alternatively, one pixel may have a configuration that includes four types of light-emitting devices: red (R), green (G), blue (B), and infrared (IR), and a light-receiving device. The light-receiving device may be provided for all pixels or for some pixels. A single pixel may have multiple light-receiving devices. For example, one pixel may have a configuration that includes three types of light-emitting devices: red (R), green (G), and blue (B), a light-receiving device sensitive to the visible light wavelength range, and a light-receiving device sensitive to the infrared light wavelength range.

[0051] A display device according to one aspect of the present invention may have the function of detecting an object in contact with the display device. The object is not particularly limited and may be a living organism or an object. If the object is a living organism, the display device may have the function of detecting, for example, a finger or a palm. As shown in Figure 1B, the light emitted by the light-emitting device of layer 57 is reflected by the finger 52 in contact with the display device 100, and the light-receiving device of layer 53 detects the reflected light. This makes it possible to detect that the finger 52 has come into contact with the display device 100. In other words, a display device according to one aspect of the present invention may have the function of a touch sensor (also called a direct touch sensor). Also, as shown in Figure 1C, the light emitted by the light-emitting device of layer 57 is reflected by the finger 52 that is close to the display device 100, and the light-receiving device of layer 53 detects the reflected light. This makes it possible to detect that the finger 52 is close to the display device 100. In other words, a display device according to one aspect of the present invention may have the function of a near-touch sensor (also called a hover sensor, hover-touch sensor, non-contact sensor, or touchless sensor).

[0052] If the display device 100 functions as a near-touch sensor, it can detect the finger 52 by being close to the display device 100, even if the finger 52 does not actually touch the display device 100. It is preferable that the display device 100 can detect the finger 52 when the distance between the display device 100 and the finger 52 is, for example, in the range of 0.1 mm to 300 mm, preferably 3 mm to 50 mm. With this configuration, it becomes possible to operate the display device 100 without directly touching it with the finger 52; in other words, it becomes possible to operate the display device 100 without contact (touchless). With this configuration, the risk of the display device 100 becoming dirty or scratched can be reduced, or it becomes possible to operate the display device 100 without the finger 52 directly touching any dirt (e.g., dust or viruses) that may adhere to the display device 100.

[0053] A display device according to one aspect of the present invention may have the function of imaging an object in contact with the display device. The display device may have the function of detecting, for example, the fingerprint of a finger 52. Figure 1D schematically shows an enlarged view of the contact area when a finger 52 is in contact with the substrate 59. Figure 1D also shows how layers 57 having light-emitting devices and layers 53 having light-receiving devices are arranged alternately.

[0054] Fingerprints are formed on finger 52 by recesses and protrusions. Therefore, as shown in Figure 1D, the protrusions of the fingerprints are in contact with the substrate 59.

[0055] Light reflected from a surface or interface can be either specular or diffuse. Specularly reflected light is highly directional, with the angle of incidence and the angle of reflection being the same, while diffusely reflected light is less directional, with low angular dependence of intensity. The light reflected from the surface of finger 52 is predominantly diffuse. On the other hand, the light reflected from the interface between substrate 59 and the atmosphere is predominantly specular.

[0056] The intensity of light reflected from the contact or non-contact surface between the finger 52 and the substrate 59, and incident on the layer 53 located directly beneath them, is the sum of specular reflection and diffuse reflection. As described above, in the recessed areas of the finger 52, the substrate 59 and the finger 52 do not come into contact, so specular reflection (indicated by the solid arrow) is dominant, while in the convex areas, they come into contact, so diffuse reflection from the finger 52 (indicated by the dashed arrow) is dominant. Therefore, the intensity of light received by the light-receiving device in the layer 53 located directly beneath the recessed areas is higher than the intensity of light received by the light-receiving device in the layer 53 located directly beneath the convex areas. Thus, the fingerprint of the finger 52 can be imaged using the light-receiving device.

[0057] The spacing of the light-receiving devices in layer 53 is set to be smaller than the distance between two protrusions of a fingerprint, preferably the distance between an adjacent recess and a protrusion, thereby enabling the acquisition of a clear fingerprint image. Since the distance between recesses and protrusions in a human fingerprint is generally between 150 μm and 250 μm, the spacing of the light-receiving devices is, for example, 400 μm or less, preferably 200 μm or less, more preferably 150 μm or less, even more preferably 120 μm or less, even more preferably 100 μm or less, and even more preferably 50 μm or less. A smaller spacing is preferable, but it can be, for example, 1 μm or more, 10 μm or more, or 20 μm or more.

[0058] Figure 1E shows an example of a fingerprint image captured by a display device according to one embodiment of the present invention. In Figure 1E, the contour of the finger 52 is shown by a dashed line and the contour of the contact area 69 is shown by a dashed line in region 65. In region 65, a high-contrast fingerprint 67 can be captured depending on the difference in the amount of light incident on the light-receiving device. Furthermore, fingerprint authentication can be performed using the acquired fingerprint image. Although an example of capturing a fingerprint using a finger as the object has been given here, the embodiment of the present invention is not limited to this. For example, the display device can detect a palm in contact with or close to the display unit. Furthermore, the display device can capture a palm print, and palm print authentication can be performed using the acquired palm print image.

[0059] As described above, in one aspect of the present invention, a light-emitting device emits light that is irradiated onto an object, and a light-receiving device can detect the light reflected by the object. Therefore, even in dark places, an object that is in contact with or close to the display unit can be detected. Furthermore, the display unit can perform authentication such as fingerprint authentication and palm print authentication.

[0060] By integrating the light-receiving device into the display unit, the need to externally attach a sensor to the display device is eliminated. Therefore, the number of components can be reduced, resulting in a smaller and lighter display device.

[0061] The substrate 50 can be a substrate with sufficient heat resistance to withstand the formation of light-emitting devices and light-receiving devices. When an insulating substrate is used as the substrate 50, glass substrates, quartz substrates, sapphire substrates, ceramic substrates, organic resin substrates, etc., can be used. In addition, semiconductor substrates such as single-crystal semiconductor substrates made of silicon or silicon carbide, polycrystalline semiconductor substrates, compound semiconductor substrates such as silicon germanium, and SOI substrates can be used.

[0062] In particular, it is preferable to use a substrate 50 on which a semiconductor circuit including semiconductor elements such as transistors is formed on the aforementioned insulating substrate or semiconductor substrate. It is preferable that the semiconductor circuit constitutes, for example, a pixel circuit, a gate line driving circuit (gate driver), a source line driving circuit (source driver), etc. In addition to the above, an arithmetic circuit, a memory circuit, etc. may also be configured.

[0063] <Configuration Example 2> [Configuration Example 2-1] The configuration of a light-emitting device and a light-receiving device applicable to a display device according to one aspect of the present invention will be described. A schematic cross-sectional view of a display device according to one aspect of the present invention is shown in Figure 2A. Figure 2A shows the configuration of a light-emitting device 20R, a light-emitting device 20G, a light-emitting device 20B, and a light-receiving device 30PS applicable to the display device.

[0064] Light-emitting devices 20R, 20G, and 20B each have the function of emitting light (hereinafter also referred to as the light-emitting function). It is preferable to use EL elements such as OLEDs (Organic Light Emitting Diodes) or QLEDs (Quantum-dot Light Emitting Diodes) for light-emitting devices 20R, 20G, and 20B. Examples of light-emitting materials for EL elements include fluorescent materials, phosphorescent materials, inorganic compounds (such as quantum dot materials), and thermally activated delayed fluorescence (TADF materials). As a TADF material, a material in which the singlet excited state and the triplet excited state are in thermal equilibrium may be used. Such TADF materials have a shorter emission lifetime (excitation lifetime), which can suppress the decrease in efficiency in the high-brightness region of the light-emitting device.

[0065] Light-emitting device 20R has an electrode 21a, an EL layer 25R, and an electrode 23. Light-emitting device 20G has an electrode 21b, an EL layer 25G, and an electrode 23. Light-emitting device 20B has an electrode 21c, an EL layer 25B, and an electrode 23. In light-emitting device 20R, the EL layer 25R sandwiched between electrode 21a and electrode 23 has at least a light-emitting layer. This light-emitting layer has a light-emitting material that emits light, and light is emitted from the EL layer 25R by applying a voltage between electrode 21a and electrode 23. Similarly, the EL layer 25G has at least a light-emitting layer. This light-emitting layer has a light-emitting material that emits light, and light is emitted from the EL layer 25G by applying a voltage between electrode 21b and electrode 23. The EL layer 25B has at least a light-emitting layer. The light-emitting layer has a light-emitting material that emits light, and by applying a voltage between electrode 21c and electrode 23, light is emitted from the EL layer 25B.

[0066] Each of the EL layers 25R, 25G, and 25B may further contain one or more of the following: a layer containing a material with high hole injection properties (hereinafter referred to as a hole injection layer), a layer containing a material with high hole transport properties (hereinafter referred to as a hole transport layer), a layer containing a material with high electron transport properties (hereinafter referred to as an electron transport layer), a layer containing a material with high electron injection properties (hereinafter referred to as an electron injection layer), a carrier block layer, an exciton block layer, and a charge generation layer. The hole injection layer, hole transport layer, electron transport layer, electron injection layer, carrier block layer, exciton block layer, and charge generation layer can also be called functional layers.

[0067] In this specification, when describing matters common to light-emitting devices 20R, 20G, and 20B, or when there is no need to distinguish between them, they may simply be referred to as "light-emitting device 20." Similarly, for components distinguished by letters, such as EL layer 25R, EL layer 25G, and EL layer 25B, when describing matters common to them, the letters may be omitted and a code may be used.

[0068] The light-receiving device 30PS has a function to detect light (hereinafter also referred to as the light-receiving function). The light-receiving device 30PS has a function to detect visible light. The light-receiving device 30PS is sensitive to visible light. It is even more preferable that the light-receiving device 30PS has a function to detect both visible light and infrared light. It is preferable that the light-receiving device 30PS is sensitive to both visible light and infrared light. For example, the light-receiving device 30PS can use a pn-type or pin-type photodiode.

[0069] The light-receiving device 30PS includes an electrode 21d, a light-receiving layer 35PS, and an electrode 23. The light-receiving layer 35PS, sandwiched between the electrode 21d and the electrode 23, has at least an active layer. The light-receiving device 30PS functions as a photoelectric conversion device, generating charge from light incident on the light-receiving layer 35PS, which can be extracted as an electric current. At this time, a voltage may be applied between the electrode 21d and the electrode 23. The amount of charge generated is determined based on the amount of light incident on the light-receiving layer 35PS.

[0070] The light-receiving layer 35PS may further have one or more of the following: a hole transport layer, an electron transport layer, a layer containing a bipolar material (a material with high electron transport and hole transport properties), and a carrier block layer. The light-receiving layer 35PS may also have a layer containing a material that can be used as a hole injection layer. In the light-receiving device 30PS, this layer can function as a hole transport layer. The light-receiving layer 35PS may also have a layer containing a material that can be used as an electron injection layer. In the light-receiving device 30PS, this layer can function as an electron transport layer. It should be noted that a material with hole injection properties can also be said to have hole transport properties. A material with electron injection properties can also be said to have electron transport properties. Therefore, in this specification, a material with hole injection properties may be referred to as a material with hole transport properties. Similarly, a material with electron injection properties may be referred to as a material with electron transport properties.

[0071] The active layer contains a semiconductor. Examples of such semiconductors include inorganic semiconductors such as silicon, and organic semiconductors containing organic compounds. In particular, it is preferable to use an organic photodiode having a layer containing an organic semiconductor as the light-receiving device 30PS. Organic photodiodes are easy to thin, lighten, and enlarge in area, and offer a high degree of freedom in shape and design, making them applicable to various display devices. Furthermore, by using an organic semiconductor, the EL layer of the light-emitting device 20 and the light-receiving layer of the light-receiving device 30PS can be formed using the same method (e.g., vacuum deposition), and common manufacturing equipment can be used, which is preferable.

[0072] In one aspect of the present invention, a display device uses organic EL devices as light-emitting devices 20R, 20G, and 20B, and preferably uses an organic photodiode as the light-receiving device 30PS. The organic EL device and the organic photodiode can be formed on the same substrate. Therefore, an organic photodiode can be incorporated into a display device using an organic EL device. In addition to the function of displaying images, the display device according to one aspect of the present invention also has one or both of the functions of imaging and sensing.

[0073] Electrodes 21a, 21b, 21c, and 21d are provided on the same plane. Figure 2A shows a configuration in which electrodes 21a, 21b, 21c, and 21d are provided on a substrate 50. Electrodes 21a, 21b, 21c, and 21d can be made from the same material. Furthermore, electrodes 21a, 21b, 21c, and 21d can be formed through the same process. For example, electrodes 21a, 21b, 21c, and 21d can be formed by processing a conductive film formed on the substrate 50 into island shapes. By forming electrodes 21a, 21b, 21c, and 21d in the same process, the productivity of the display device can be increased.

[0074] Electrodes 21a, 21b, 21c, and 21d may be formed by different processes. Furthermore, the film thicknesses of electrodes 21a, 21b, 21c, and 21d may be different. By varying the film thicknesses of electrodes 21a, 21b, 21c, and 21d, they can be used as an optical adjustment layer.

[0075] Electrodes 21a, 21b, 21c, and 21d can each be called pixel electrodes. Electrode 23 is a layer common to the light-emitting device 20R, light-emitting device 20G, light-emitting device 20B, and light-receiving device 30PS, and can be called a common electrode. Of the pixel electrodes and common electrodes, the electrodes on the side that emits or receives light should preferably use a conductive film that transmits visible light and infrared light. For the electrodes on the side that does not emit or receive light, it is preferable to use a conductive film that reflects visible light and infrared light.

[0076] Figure 2A schematically shows the configuration in which electrodes 21a, 21b, 21c, and 21d function as anodes and electrode 23 functions as a cathode in each of the light-emitting devices 20R, 20G, 20B, and 30PS. In Figure 2A, to make the orientation of the anode and cathode clearer, the circuit symbol for a light-emitting diode is shown to the left of the light-emitting device 20R, and the circuit symbol for a photodiode is shown to the right of the light-receiving device 30PS. In addition, electrons are indicated by circles with a minus sign (-), holes are indicated by circles with a plus sign (+), and the direction of electron and hole flow is schematically indicated by arrows.

[0077] In the light-emitting devices 20R, 20G, and 20B, electrodes 21a, 21b, and 21c, which function as anodes, are electrically connected to a first wiring that supplies a first potential. In the light-emitting devices 20R, 20G, 20B, and 30PS, electrode 23, which functions as a cathode, is electrically connected to a second wiring that supplies a second potential. The second potential is lower than the first potential. In the 30PS, electrode 21d, which functions as an anode, is electrically connected to a third wiring that supplies a third potential. Here, a reverse bias voltage is applied to the 30PS. That is, the third potential is lower than the second potential.

[0078] A specific example of the configuration shown in Figure 2A is shown in Figure 2B. In the light-emitting device 20R, the EL layer 25R has a first functional layer 27a, a light-emitting layer 41R, and a second functional layer 29a stacked in this order. In the light-emitting device 20G, the EL layer 25G has a first functional layer 27b, a light-emitting layer 41G, and a second functional layer 29b stacked in this order. In the light-emitting device 20B, the EL layer 25B has a first functional layer 27c, a light-emitting layer 41B, and a second functional layer 29c stacked in this order.

[0079] In addition, the configuration of the light-emitting device 20R having a first functional layer 27a, a light-emitting layer 41R, and a second functional layer 29a provided between a pair of electrodes (electrode 21a and electrode 23) can function as a single light-emitting unit, and in this specification, the configuration of the light-emitting device 20R may be referred to as a single structure. The same applies to the light-emitting devices 20G and 20B.

[0080] The first functional layers 27a, 27b, and 27c are located on the side of electrodes 21a, 21b, and 21c, which function as anodes, in the light-emitting devices 20R, 20G, and 20B. Each of the first functional layers 27a, 27b, and 27c can be a hole transport layer or a hole injection layer. Alternatively, each of the first functional layers 27a, 27b, and 27c may have a laminated structure of a hole injection layer and a hole transport layer on the hole injection layer. Furthermore, the hole injection layer may have a laminated structure, or the hole transport layer may have a laminated structure. Alternatively, each of the first functional layers 27a, 27b, and 27c may contain a material having hole transport properties and a material having hole injection properties.

[0081] The first functional layer 27a, the first functional layer 27b, and the first functional layer 27c can be made from the same material. Furthermore, the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c can be formed through the same process. For example, the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c can be formed by processing the film that will become the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c. By forming the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c in the same process, the productivity of the display device can be increased.

[0082] The second functional layers 29a, 29b, and 29c are located on the electrode 23 side, which functions as a cathode, in the light-emitting devices 20R, 20G, and 20B. The second functional layers 29a, 29b, and 29c can each be an electron transport layer or an electron injection layer. Alternatively, the second functional layers 29a, 29b, and 29c may each be a laminated structure of an electron transport layer and an electron injection layer on the electron transport layer. Furthermore, the electron injection layer may have a laminated structure, or the electron transport layer may have a laminated structure. Alternatively, the second functional layers 29a, 29b, and 29c may each contain an electron-transporting material and an electron-injecting material.

[0083] The second functional layer 29a, the second functional layer 29b, and the second functional layer 29c can be made from the same material. Furthermore, the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c can be formed through the same process. For example, the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c can be formed by processing the film that will become the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c. By forming the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c in the same process, the productivity of the display device can be increased.

[0084] As shown in Figure 2B, in the light-receiving device 30PS, the light-receiving layer 35PS has a third functional layer 37PS, an active layer 43PS, and a fourth functional layer 39PS stacked in this order.

[0085] The third functional layer 37PS, located on the electrode 21d side which functions as the anode of the photodetector 30PS, can be a hole transport layer. The hole-transporting material contained in the third functional layer 37PS may be different from the hole-transporting material contained in the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c. It is preferable that the third functional layer 37PS of the photodetector 30PS be formed by a different process than the layers constituting the light-emitting device 20 (for example, the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c). By forming it by a different process, a material more suitable for the photodetector 30PS can be applied to the third functional layer 37PS. Similarly, a material more suitable for the light-emitting device 20 can be applied to the first functional layer 27.

[0086] The third functional layer 37PS can be made of the same material used for the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c. The hole-transporting material contained in the third functional layer 37PS may be different from or the same as the hole-transporting material contained in the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c. The third functional layer 37PS may have a laminated structure.

[0087] When the hole-transporting material contained in the third functional layer 37PS is different from the hole-transporting material contained in the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c, it is preferable to select a material with optimal hole-transporting properties for each device. On the other hand, when the hole-transporting material contained in the third functional layer 37PS is the same from the hole-transporting material contained in the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c, it is preferable to manufacture them using a common apparatus (e.g., a common deposition apparatus), which can reduce manufacturing costs.

[0088] The fourth functional layer 39PS, located on the electrode 23 side which functions as the cathode of the photodetector 30PS, can be an electron transport layer. The electron transport material contained in the fourth functional layer 39PS may be different from the electron transport material contained in the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c. It is preferable that the fourth functional layer 39PS of the photodetector 30PS be formed by a different process than the layers constituting the light-emitting device 20 (for example, the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c). By forming it by a different process, a material more suitable for the photodetector 30PS can be applied to the fourth functional layer 39PS. Similarly, a material more suitable for the light-emitting device 20 can be applied to the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c.

[0089] The fourth functional layer 39PS can be made from the same material used for the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c. The electron-transporting material contained in the fourth functional layer 39PS may be different from or the same as the electron-transporting material contained in the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c. The fourth functional layer 39PS may have a laminated structure.

[0090] When the electron-transporting material contained in the fourth functional layer 39PS is different from the electron-transporting materials contained in the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c, it is preferable to select the electron-transporting material best suited to each device. On the other hand, when the electron-transporting material contained in the fourth functional layer 39PS is the same from the electron-transporting materials contained in the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c, it is preferable to manufacture them using a common apparatus (e.g., a common deposition apparatus), thereby reducing manufacturing costs.

[0091] Furthermore, the third functional layer 37PS may include a layer that functions as a hole injection layer in the light-emitting device, that is, a layer containing a material with high hole injection capabilities. The hole injection layer can function as a hole transport layer in the photodetector. The fourth functional layer 39PS may include a layer that functions as an electron injection layer in the light-emitting device, that is, a layer containing a material with high electron injection capabilities. The electron injection layer can function as an electron transport layer in the photodetector.

[0092] As shown in Figure 2B and other figures, it is preferable that the EL layer 25R, EL layer 25G, EL layer 25B, and light-receiving layer 35PS do not have any common layers. Furthermore, it is preferable that the EL layer 25R, EL layer 25G, EL layer 25B, and light-receiving layer 35PS do not have any regions in contact with each other. In other words, it is preferable that the EL layer 25R, EL layer 25G, EL layer 25B, and light-receiving layer 35PS are separate.

[0093] Because the EL layers 25 of two adjacent light-emitting devices 20 are separated, leakage current between the light-emitting devices 20 can be suppressed. In other words, the phenomenon of light emitting from devices other than the desired one (also known as crosstalk) can be suppressed, resulting in a display device with high display quality.

[0094] Because the light-receiving layer 35PS of the light-receiving device 30PS is separated from the EL layer 25 of the adjacent light-emitting device 20, leakage current flowing from the light-emitting device 20 to the light-receiving device 30PS (also known as side leakage) can be suppressed. Therefore, a light-receiving device 30PS with a high signal-to-noise ratio (SNR) and high accuracy can be achieved.

[0095] In one embodiment of the present invention, side leakage between the light-emitting device 20 and the light-receiving device 30PS is suppressed, allowing the distance between the light-emitting device 20 and the light-receiving device 30PS to be reduced. In other words, the ratio of the light-emitting device 20 and the light-receiving device 30PS to a pixel (hereinafter also referred to as the aperture ratio) can be increased. Furthermore, the size of the pixels can be reduced, and the resolution of the display device can be increased. Therefore, a display device with a light detection function and a high aperture ratio can be realized. In addition, a display device with a light detection function and high resolution can be realized.

[0096] The resolution of the light-receiving device 30PS is 100 ppi or more, preferably 200 ppi or more, more preferably 300 ppi or more, more preferably 400 ppi or more, and even more preferably 500 ppi or more, and can be 2000 ppi or less, 1000 ppi or less, or 600 ppi or less, etc. In particular, by setting the resolution of the light-receiving device 30PS to 200 ppi or more and 600 ppi or less, preferably 300 ppi or more and 600 ppi or less, it can be suitably used for fingerprint imaging.

[0097] When performing fingerprint authentication using a display device according to one aspect of the present invention, increasing the resolution of the light-receiving device 30PS allows for the extraction of, for example, the feature points (Minutia) of the fingerprint with high precision, thereby improving the accuracy of fingerprint authentication. Furthermore, a resolution of 500 ppi or higher is preferable because it allows compliance with standards such as those of the National Institute of Standards and Technology (NIST). Assuming a resolution of 500 ppi for the light-receiving device, the size of each pixel becomes 50.8 μm, which is sufficient resolution for imaging the width of a fingerprint (typically between 300 μm and 500 μm).

[0098] [Configuration Example 2-2] Figure 2C shows a configuration different from those shown in Figures 2A and 2B. The display device shown in Figure 2C schematically illustrates a configuration in which, in the light-emitting devices 20R, 20G, and 20B, electrodes 21a, 21b, and 21c function as anodes, and electrode 23 functions as a cathode, and in the light-receiving device 30PS, electrode 21d functions as a cathode and electrode 23 functions as an anode.

[0099] In the light-emitting devices 20R, 20G, and 20B, electrodes 21a, 21b, and 21c, which function as anodes, are electrically connected to a first wiring that supplies a first potential. Electrode 23, which functions as a cathode in the light-emitting devices 20R, 20G, and 20B, and also functions as an anode in the light-receiving device 30PS, is electrically connected to a second wiring that supplies a second potential. The second potential is lower than the first potential. Electrode 21d, which functions as a cathode in the light-receiving device 30PS, is electrically connected to a third wiring that supplies a third potential. The third potential is higher than the second potential.

[0100] As shown in Figure 2C, the electrode 23, which functions as a common electrode, can be configured to function as either the anode or cathode in the light-emitting devices 20R, 20G, and 20B, and as the other anode or cathode in the light-receiving device 30PS. With this configuration, the potential difference between the pixel electrodes (electrodes 21a, 21b, and 21c) of the light-emitting device 20 and the pixel electrode (electrode 21d) of the light-receiving device 30PS can be reduced, and leakage between pixel electrodes (hereinafter also referred to as side leakage) can be suppressed. Therefore, a light-receiving device 30PS with a high signal-to-noise ratio and high accuracy can be obtained.

[0101] For example, the first potential (the potential supplied to electrodes 21a, 21b, and 21c) can be set to 12V, the second potential (the potential supplied to electrode 23) to 0V, and the third potential (the potential supplied to electrode 21d) to 4V. By using such a configuration, the potential difference between the pixel electrodes (electrodes 21a, 21b, and 21c) of the light-emitting device 20 and the pixel electrode (electrode 21d) of the light-receiving device 30PS can be reduced, thereby suppressing side leakage between the light-emitting device 20 and the light-receiving device 30PS.

[0102] Furthermore, since the difference between the highest and lowest potentials of the first, second, and third potentials can be reduced, a display device with low power consumption can be achieved.

[0103] A specific example of the configuration shown in Figure 2C is shown in Figure 2D. Detailed explanations of light-emitting devices 20R, 20G, and 20B are omitted as they can be found in the previously mentioned description.

[0104] The third functional layer 37PS, located on the electrode 21d side which functions as the cathode of the photodetector 30PS, can be an electron transport layer. The electron transport material contained in the third functional layer 37PS may be different from the electron transport material contained in the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c. The third functional layer 37PS can be made from the same material used for the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c. The electron transport material contained in the third functional layer 37PS may be the same as the electron transport material contained in the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c.

[0105] The fourth functional layer 39PS, located on the electrode 23 side which functions as the anode of the photodetector 30PS, can be a hole transport layer. The hole-transporting material contained in the fourth functional layer 39PS may be different from the hole-transporting material contained in the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c. The fourth functional layer 39PS can be made from the same material used for the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c. The hole-transporting material contained in the fourth functional layer 39PS may be the same as the hole-transporting material contained in the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c.

[0106] Furthermore, the third functional layer 37PS may have a layer that functions as an electron injection layer in the light-emitting device, that is, a layer containing a material with high electron injection potential. The fourth functional layer 39PS may have a layer that functions as a hole injection layer in the light-emitting device, that is, a layer containing a material with high hole injection potential.

[0107] In this embodiment, a configuration has been described in which electrodes 21a, 21b, and 21c function as anodes and electrode 23 functions as a cathode in the light-emitting device 20. However, the present invention is not limited to this configuration. In the light-emitting device 20, electrodes 21a, 21b, and 21c can function as cathodes and electrode 23 can function as anode. In this case, the first functional layers 27a, 27b, and 27c can be either an electron transport layer or an electron injection layer, or both. The second functional layers 29a, 29b, and 29c can be either a hole transport layer or a hole injection layer, or both.

[0108] [Configuration Example 2-3] Figure 3A shows a configuration different from the one shown in Figure 2B. The light-emitting devices 20R, 20G, and 20B shown in Figure 3A have a first functional layer 27 instead of the first functional layers 27a, 27b, and 27c, and a second functional layer 29 instead of the second functional layers 29a, 29b, and 29c. The first functional layer 27 is a layer common to the light-emitting devices 20R, 20G, and 20B, and can be called the first common layer. Similarly, the second functional layer 29 is a layer common to the light-emitting devices 20R, 20G, and 20B, and can be called the second common layer.

[0109] As shown in Figure 3A, the first functional layer 27 located on the side of electrodes 21a, 21b, and 21c, which function as anodes for light-emitting devices 20R, 20G, and 20B, can be a hole transport layer or a hole injection layer. Alternatively, the first functional layer 27 may have a laminated structure of a hole injection layer and a hole transport layer on the hole injection layer. A detailed explanation of the first functional layer 27 is omitted as it can be found in the descriptions of the first functional layer 27a, the first functional layer 27b, and the first functional layer 27c.

[0110] The second functional layer 29 located on the electrode 23 side, which functions as the cathode of the light-emitting devices 20R, 20G, and 20B, can be an electron transport layer or an electron injection layer. Alternatively, the second functional layer 29 may have a laminated structure of an electron transport layer and an electron injection layer on the electron transport layer. A detailed explanation of the second functional layer 29 is omitted here, as it can be found in the descriptions of the second functional layer 29a, the second functional layer 29b, and the second functional layer 29c.

[0111] Furthermore, a third common layer may be provided between the electrode 23 and the second functional layer 29, and between the electrode 23 and the fourth functional layer 39PS. The third common layer may, for example, have an electron injection layer. Alternatively, the third common layer may have a laminated structure of an electron transport layer and an electron injection layer on the electron transport layer. The third common layer is a layer common to the light-emitting device 20R, light-emitting device 20G, light-emitting device 20B, and light-receiving device 30PS. When an electron injection layer is used for the third common layer, the electron injection layer functions as an electron transport layer in the light-receiving device 30PS.

[0112] Furthermore, as shown in Figure 3B, the light-receiving device 30PS may be configured such that electrode 21d functions as the cathode and electrode 23 functions as the anode.

[0113] Furthermore, a third common layer may be provided between the electrode 23 and the second functional layer 29, and between the electrode 23 and the fourth functional layer 39PS. Since the third common layer can be described in the preceding section, a detailed explanation is omitted. Note that if an electron injection layer is used for the third common layer, the electron injection layer does not need to have a specific function in the photodetector 30PS.

[0114] 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).

[0115] In a light-emitting device, the hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light-emitting layer. In a light-receiving device, the hole transport layer is a layer that transports holes generated in the active layer based on incident light to the anode. The hole transport layer is a layer containing a hole-transporting material. The hole-transporting material is 10 -6 cm 2Materials 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 are those with high hole transport capabilities, such as π-electron-rich heteroaromatic compounds (e.g., carbazole derivatives, thiophene derivatives, furan derivatives, etc.) and aromatic amines (compounds having an aromatic amine skeleton).

[0116] In a light-emitting device, the electron transport layer is a layer that transports electrons injected from the cathode to the light-emitting layer by the electron injection layer. In a light-receiving device, the electron transport layer is a layer that transports electrons generated in the active layer based on incident light to the cathode. The electron transport layer is a layer containing an electron-transporting material. The electron-transporting material has a density of 1 × 10⁻¹⁶ -6 cm 2 Materials having an electron mobility of / Vs or higher are preferred. However, other materials can also be used as long as they have higher electron transport capabilities than holes. Electron transport 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, etc., 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.

[0117] 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 properties. Alkali metals, alkaline earth metals, or compounds thereof can be used as the material with high electron injection properties. Composite materials containing both electron transport materials and donor materials (electron-donating materials) can also be used as the material with high electron injection properties.

[0118] The electron injection layer includes, for example, lithium, cesium, ytterbium, 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. Furthermore, the electron injection layer may have a multilayer structure of two or more layers. For example, this multilayer structure may consist of lithium fluoride as the first layer and ytterbium as the second layer.

[0119] Alternatively, the electron injection layer may be made of an electron-transporting material. 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.

[0120] 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.

[0121] For example, 4,7-diphenyl-1,10-phenanthroline (abbreviated as BPhen), 2,9-di(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.

[0122] The charge generation layer can preferably use a material applicable to the electron injection layer, such as lithium. Alternatively, the charge generation layer can preferably use a material applicable to the hole injection layer. Furthermore, the charge generation layer can include a layer containing a hole transport material and an acceptor material (electron-accepting material). Alternatively, the charge generation layer can include a layer containing an electron transport material and a donor material. By forming a charge generation layer having such layers, the increase in driving voltage when light-emitting units are stacked can be suppressed.

[0123] The active layer contains a semiconductor. Examples of such semiconductors include inorganic semiconductors such as silicon, and organic semiconductors containing organic compounds. In this embodiment, an example is shown in which an organic semiconductor is used as the semiconductor of the active layer. Using an organic semiconductor is preferable because the light-emitting layer and the active layer can be formed using the same method (for example, vacuum deposition), and the manufacturing equipment can be shared.

[0124] As a material for the n-type semiconductor in the active layer, fullerene (e.g., C 60 , C 70Examples of electron-accepting organic semiconductor materials include fullerenes, fullerene derivatives, etc. Fullerene has a soccer ball-like shape, which is energetically stable. Fullerene has deep (low) HOMO and LUMO levels. Due to the deep LUMO level, fullerene has extremely high electron-accepting (acceptor) properties. Usually, like benzene, when π-electron conjugation (resonance) spreads in a plane, the electron-donating (donor) property increases. However, because fullerene has a spherical shape, despite the large spread of π-electron conjugation, its electron-accepting property is high. High electron-accepting property is beneficial for light-receiving devices because it causes charge separation efficiently at high speed. C 60 and C 70 both have broad absorption bands in the visible light region. In particular, C 70 is preferable because it has a larger π-electron conjugation system than C 60 and also has a broad absorption band in the long wavelength region. In addition, examples of fullerene derivatives include [6,6]-Phenyl-C 71 -butyric acid methyl ester (abbreviation: PC 70 BM), [6,6]-Phenyl-C 61 -butyric acid methyl ester (abbreviation: PC 60 BM), 1’,1’’,4’,4’’-Tetrahydro-di[1,4]methanonaphthaleno[1,2:2’,3’,56,60:2’’,3’’][5,6]fullerene-C 60 (abbreviation: ICBA), etc.

[0125] Examples of materials for n-type semiconductors include perylene tetracarboxylic acid derivatives such as N,N’-dimethyl-3,4,9,10-perylene tetracarboxylic acid diimide (abbreviation: Me-PTCDI).

[0126] Examples of materials for n-type semiconductors include 2,2’-(5,5’-(thieno[3,2-b]thiophene-2,5-diyl)bis(thiophene-5,2-diyl))bis(methane-1-yl-1-ylidene)dimalononitrile (abbreviation: FT2TDMN).

[0127] Examples of n-type semiconductor 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, oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, naphthalene derivatives, anthracene derivatives, coumarin derivatives, rhodamine derivatives, triazine derivatives, and quinone derivatives.

[0128] Examples of p-type semiconductor materials for the active layer include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanthene (DBP), zinc phthalocyanine (ZnPc), tin phthalocyanine (SnPc), quinacridone, and rubrene.

[0129] Examples of materials for p-type semiconductors include carbazole derivatives, thiophene derivatives, furan derivatives, and compounds having an aromatic amine skeleton. Furthermore, examples of materials for p-type semiconductors include naphthalene derivatives, anthracene derivatives, pyrene derivatives, triphenylene derivatives, fluorene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, indole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, indolocarbazole derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, quinacridone derivatives, rubrene derivatives, tetracene derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, and polythiophene derivatives.

[0130] The HOMO level of electron-donating organic semiconductor materials is preferably shallower (higher) than the HOMO level of electron-accepting organic semiconductor materials. The LUMO level of electron-donating organic semiconductor materials is preferably shallower (higher) than the LUMO level of electron-accepting organic semiconductor materials.

[0131] It is preferable to use spherical fullerenes as electron-accepting organic semiconductor materials and organic semiconductor materials with a near-planar shape as electron-donating organic semiconductor materials. Molecules with similar shapes tend to aggregate, and when molecules of the same type aggregate, their molecular orbital energy levels are close, which can improve carrier transport.

[0132] For example, the active layer is preferably formed by co-depositing an n-type semiconductor and a p-type semiconductor. Alternatively, the active layer may be formed by stacking an n-type semiconductor and a p-type semiconductor.

[0133] The light-emitting device and the light-receiving 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 and the light-receiving device can be formed by methods such as vapor deposition (including vacuum deposition), transfer, printing, inkjet, and coating, respectively.

[0134] For example, polymer compounds such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS), and inorganic compounds such as molybdenum oxide and copper iodide (CuI) can be used as hole transporting materials or electron blocking materials. In addition, inorganic compounds such as zinc oxide (ZnO) and organic compounds such as polyethyleneimine ethoxylate (PEIE) can be used as electron transporting materials or hole blocking materials. The light-receiving device may have, for example, a mixed film of PEIE and ZnO.

[0135] The active layer can use polymer compounds such as Poly[[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl]-2,5-thiophenediyl[5,7-bis(2-ethylhexyl)-4,8-dioxo-4H,8H-benzo[1,2-c:4,5-c']dithiophene-1,3-diyl]]polymer (abbreviated as PBDB-T) or PBDB-T derivatives, which function as donors. For example, a method can be used in which an acceptor material is dispersed in PBDB-T or a PBDB-T derivative.

[0136] A more specific configuration example of a display device according to one aspect of the present invention will be described.

[0137] <Configuration Example 3> [Configuration Example 3-1] Figure 4A shows a schematic top view illustrating an example configuration of a display device 100A according to one aspect of the present invention. The display device 100A has a display unit in which a plurality of pixels 103 are arranged in a matrix, and a connection unit 140 outside the display unit.

[0138] Each pixel 103 has multiple subpixels. Figure 4A shows an example where pixel 103 has subpixels 120R, 120G, 120B, and 130. Subpixel 120R has a light-emitting device 110R that emits red light. Subpixel 120G has a light-emitting device 110G that emits green light. Subpixel 120B has a light-emitting device 110B that emits blue light. Subpixel 130 has a light-receiving device 150. In Figure 4A, the labels R, G, and B are added to the light-emitting area of ​​the light-emitting device 110 for easier identification of each device. The label PS is added to the light-receiving area of ​​the light-receiving device 150.

[0139] Figure 4B shows cross-sectional views corresponding to the dashed lines A1-A2 and D1-D2 in Figure 4A. The light-emitting devices 110R, 110G, 110B, and 150 are provided on the substrate 101.

[0140] In this specification, for example, when we refer to "B on A" or "B below A," it is not necessarily required that A and B have areas in contact.

[0141] The light-emitting device 110R includes an electrode 111a, a common electrode 123, and an EL layer 175R sandwiched between the electrode 111a and the common electrode 123. The EL layer 175R includes a first functional layer 115a, a second functional layer 116a, and a light-emitting layer 112R sandwiched between the first functional layer 115a and the second functional layer 116a.

[0142] The light-emitting device 110G includes an electrode 111b, a common electrode 123, and an EL layer 175G sandwiched between the electrode 111b and the common electrode 123. The EL layer 175G includes a first functional layer 115b, a second functional layer 116b, and a light-emitting layer 112G sandwiched between the first functional layer 115b and the second functional layer 116b.

[0143] The light-emitting device 110B includes an electrode 111c, a common electrode 123, and an EL layer 175B sandwiched between the electrode 111c and the common electrode 123. The EL layer 175B includes a first functional layer 115c, a second functional layer 116c, and a light-emitting layer 112B sandwiched between the first functional layer 115c and the second functional layer 116c.

[0144] The light-receiving device 150 includes an electrode 111d, a common electrode 123, and a light-receiving layer 177 sandwiched between the electrode 111d and the common electrode 123. The light-receiving layer 177 includes a third functional layer 155, a fourth functional layer 156, and an active layer 157 sandwiched between the third functional layer 155 and the fourth functional layer 156.

[0145] Electrodes 111a, 111b, 111c, and 111d each function as pixel electrodes of the light-emitting device 110 or the light-receiving device 150.

[0146] Light-emitting devices 110R, 110G, and 110B can be configured to match the configurations of light-emitting devices 20R, 20G, and 20B described above. Light-receiving device 150 can be configured to match the configuration of light-receiving device 30PS described above.

[0147] The common electrode 123 is provided in common to both the light-emitting device 110 and the light-receiving device 150. Other elements of the light-emitting device 110 and the light-receiving device 150, besides the common electrode 123, are not common to both devices and are provided separately.

[0148] Specifically, electrodes 111a, 111b, 111c, and 111d are not common to the light-emitting device 110 and the light-receiving device 150, and are provided separately. The first functional layers 115a, 115b, and 115c are not common to the light-emitting device 110, and are provided separately. Similarly, light-emitting layers 112R, 112G, and 112B are not common to the light-emitting device 110, and are provided separately. Similarly, the second functional layers 116a, 116b, and 116c are not common to the light-emitting device 110, and are provided separately.

[0149] The third functional layer 155, the active layer 157, and the fourth functional layer 156 of the light-receiving device 150 are not shared with the light-emitting device 110 and are provided separately. By providing the third functional layer 155, the active layer 157, and the fourth functional layer 156 of the light-receiving device 150 separately from the light-emitting device 110, leakage current flowing from the light-emitting device 110 to the light-receiving device 150 can be suppressed. Therefore, a light-receiving device 150 with a high signal-to-noise ratio and high accuracy can be achieved.

[0150] It is preferable that the third functional layer 155 of the light-receiving device 150 be formed by a different process than the functional layers of the light-emitting device 110 (for example, the first functional layer 115a, the first functional layer 115b, and the first functional layer 115c). By forming it by a different process, a material more suitable for the light-receiving device 150 can be applied to the third functional layer 155. In other words, the third functional layer 155 can have a configuration in which the organic compound is different from the organic compound in the functional layer of the light-emitting device 110.

[0151] Similarly, it is preferable that the fourth functional layer 156 of the light-receiving device 150 be formed using a different process than the functional layers of the light-emitting device 110 (for example, the second functional layer 116a, the second functional layer 116b, and the second functional layer 116c). By forming it using a different process, a material more suitable for the light-receiving device 150 can be applied to the fourth functional layer 156. In other words, the fourth functional layer 156 can have a configuration in which the organic compound is different from the organic compound in the functional layer of the light-emitting device 110.

[0152] The first functional layer 115a, the first functional layer 115b, the first functional layer 115c, and the third functional layer 155 each have a region that is in contact with the upper surface of the electrode 111.

[0153] A conductive film that is transparent to visible light is used on either electrode 111 or common electrode 123, and a conductive film that is reflective is used on the other. By making electrode 111 transparent and common electrode 123 reflective, the display device 100A can be made into a bottom-emission type display device. On the other hand, by making electrode 111 reflective and common electrode 123 transparent, the display device 100A can be made into a top-emission type display device. Furthermore, by making both electrode 111 and common electrode 123 transparent, the display device 100A can be made into a dual-emission type display device.

[0154] The electrodes 111a, 111b, 111c, and 111d may have different film thicknesses and be used as optical adjustment layers. By providing optical adjustment layers, a light-emitting device 110 and a light-receiving device 150 having a microcavity structure (micro-resonator structure) can be created. When applying a microcavity structure, for example, electrode 111 can use a laminated structure of a conductive layer that is reflective to visible light and a conductive layer that is translucent on the conductive layer (also called an optical adjustment layer). By making the film thickness of the optical adjustment layer different for electrodes 111a, 111b, 111c, and 111d, the respective optical path lengths can be made different. A conductive film having both reflective and translucent properties can be used for the common electrode 123.

[0155] By applying a microcavity structure, the light-emitting devices 110R, 110G, and 110B can be made into light-emitting devices with high color purity by intensifying light of a specific wavelength. The light-receiving device 150 can be made into a light-receiving device with high sensitivity by intensifying light of a specific wavelength to be detected.

[0156] As shown in Figure 4B, an insulating layer 182 is provided so as to be embedded between two adjacent light-emitting devices 110 and between adjacent light-emitting devices 110 and a light-receiving device 150. Similarly, if two light-receiving devices 150 are adjacent, an insulating layer 182 may also be provided between the light-receiving devices. Preferably, the insulating layer 182 has regions that are in contact with the sides of the EL layer 175R, EL layer 175G, EL layer 175B, light-receiving layer 177, electrode 111a, electrode 111b, electrode 111c, and electrode 111d. By providing an insulating layer 182, it is possible to suppress the intrusion of impurities into the interior from the sides of the EL layer 175 and the light-receiving layer 177, resulting in a highly reliable display device. In particular, it is preferable that the insulating layer 182 has regions that are in contact with the sides of the light-emitting layer 112 and the active layer 157. Examples of such impurities include oxygen and water. A common electrode 123 is provided on the insulating layer 182.

[0157] By providing an insulating layer 182 between adjacent light-emitting devices 110, the EL layers 175R, 175G, and 175G can be configured so that they do not come into contact with each other. This prevents current from flowing through two adjacent EL layers 175 and causing unintended light emission. Therefore, a display device with high contrast and high display quality can be achieved.

[0158] Similarly, by providing an insulating layer 182 between adjacent light-emitting devices 110 and light-receiving devices 150, the EL layer 175 and the light-receiving layer 177 can be configured not to come into contact. This suppresses leakage current flowing from adjacent light-emitting devices 110 to light-receiving devices 150 (side leakage). Therefore, a light-receiving device 150 with a high signal-to-noise ratio and high accuracy can be achieved.

[0159] Between adjacent light-emitting devices 110, a step difference occurs near the edge of the EL layer 175 between the region where the EL layer 175 is provided and the region where the EL layer 175 is not provided. In one embodiment of the present invention, the display device can reduce this step difference by providing an insulating layer 182, thereby improving the step-coverage of the common electrode 123 formed thereon. Therefore, connection failures due to step breaks in the common electrode 123 can be suppressed. Alternatively, it is possible to suppress the local thinning of the film thickness of the common electrode 123 due to the step difference, which would increase electrical resistance.

[0160] In one aspect of the present invention, by providing an insulating layer 182 between adjacent EL layers 175, the irregularities on the surface of the common electrode 123 can be reduced, thereby improving the step coverage of the common electrode 123 near the edges of the EL layer 175 and achieving good conductivity of the common electrode 123.

[0161] Similarly, between adjacent light-emitting devices 110 and light-receiving devices 150, and between adjacent light-receiving devices 150, a step difference occurs between the region where the light-receiving layer 177 is provided and the region where the light-receiving layer 177 is not provided. By providing an insulating layer 182, this step difference can be reduced, and the step-coverage of the common electrode 123 formed thereon can be improved.

[0162] At the edge of the EL layer 175, the step difference between the upper surface of the EL layer 175 and the upper surface of the insulating layer 182 can be reduced, that is, by making the height of the upper surface of the EL layer 175 and the height of the upper surface of the insulating layer 182 the same or approximately the same, the step coverage of the common electrode 123 can be improved. Similarly, at the edge of the light-receiving layer 177, the step difference between the upper surface of the light-receiving layer 177 and the upper surface of the insulating layer 182 can be reduced, that is, by making the height of the upper surface of the light-receiving layer 177 and the height of the upper surface of the insulating layer 182 the same or approximately the same, the step coverage of the common electrode 123 can be improved.

[0163] Figure 4B shows a configuration in which the height of the upper surface of the insulating layer 182 is equal to or approximately equal to the height of the upper surface of the EL layer 175 and the upper surface of the light-receiving layer 177, but the present invention is not limited to this. The height of the upper surface of the insulating layer 182 does not have to be equal to the height of the upper surface of the EL layer 175 and the upper surface of the light-receiving layer 177. The height of the upper surface of the insulating layer 182 may be higher or lower than the height of the upper surface of the EL layer 175. The height of the upper surface of the insulating layer 182 may be higher or lower than the height of the upper surface of the light-receiving layer 177. Furthermore, the insulating layer 182 may have a region in contact with the upper surface of the EL layer 175 and a region in contact with the upper surface of the light-receiving layer 177.

[0164] Furthermore, the heights of the upper surfaces of the EL layer 175R, EL layer 175G, EL layer 175B, and light-receiving layer 177 may be different. Also, the heights of the upper surface of the insulating layer 182 may be different at the ends of the EL layer 175R, EL layer 175G, EL layer 175B, and light-receiving layer 177. For example, at the end of the EL layer 175R, the height of the upper surface of the EL layer 175R may be higher than the height of the upper surface of the insulating layer 182; at the end of the EL layer 175G, the height of the upper surface of the EL layer 175G may be higher than the height of the upper surface of the insulating layer 182; at the end of the EL layer 175B, the height of the upper surface of the EL layer 175B may be the same as or approximately the same as the height of the upper surface of the insulating layer 182; and at the end of the light-receiving layer 177, the height of the upper surface of the light-receiving layer 177 may be lower than the height of the upper surface of the insulating layer 182.

[0165] The insulating layer 182 can have a laminated structure of insulating layer 182a and insulating layer 182b on insulating layer 182a. Preferably, insulating layer 182a has a region in contact with the side surface of EL layer 175 and the side surface of light receiving layer 177. Preferably, insulating layer 182a has a region in contact with the side surface of electrode 111. Insulating layer 182b is provided on insulating layer 182a. In cross-sectional view, insulating layer 182b is provided in contact with insulating layer 182a so as to fill the recesses of insulating layer 182a.

[0166] The insulating layer 182a functions as a protective insulating layer for the EL layer 175 and the light-receiving layer 177. Preferably, the insulating layer 182a has barrier properties against at least one of oxygen and water. By providing the insulating layer 182a, it is possible to suppress the intrusion of oxygen, water, or their constituent elements into the interior from the sides of the EL layer 175 and the light-receiving layer 177, thereby enabling a highly reliable display device. Preferably, the insulating layer 182a covers the sides of the light-emitting layer 112 and the active layer 157.

[0167] In a cross-sectional view, if the width (film thickness) of the insulating layer 182a in the region in contact with the side surface of the EL layer 175 or the light-receiving layer 177 is large, the gap between the EL layer 175 and the light-receiving layer 177 will increase, which may result in a lower aperture ratio. Conversely, if the width (film thickness) of the insulating layer 182a is small, the effect of suppressing the intrusion of oxygen, water, or their constituent elements into the interior from the side surface of the EL layer 175 and the light-receiving layer 177 may be reduced. The width (film thickness) of the insulating layer 182a in the region in contact with the side surface of the EL layer 175 or the light-receiving layer 177 is preferably 3 nm to 200 nm, more preferably 3 nm to 150 nm, more preferably 5 nm to 150 nm, more preferably 5 nm to 100 nm, more preferably 10 nm to 100 nm, and more preferably 10 nm to 50 nm. By setting the width (film thickness) of the insulating layer 182a within the aforementioned range, a display device with a high aperture ratio and high reliability can be obtained.

[0168] The insulating layer 182a can be an insulating layer having an inorganic material. As the insulating layer 182a, aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indium gallium zinc oxide, silicon oxide, silicon oxide nitride, or silicon oxide nitride can be used as a single layer or in a laminated form. In particular, aluminum oxide is preferred because it has a high selectivity ratio with the EL layer 175 during etching and has the function of protecting the EL layer 175 during the formation of the insulating layer 182a, which will be described later. In particular, by using inorganic insulating materials such as aluminum oxide, hafnium oxide, and silicon oxide formed by the ALD method as the insulating layer 182a, a film with fewer pinholes can be made, and an insulating layer 182a with excellent function in protecting the EL layer 175 and the light-receiving layer 177 can be made.

[0169] In this specification, "oxide-nitride" refers to a material in which the oxygen content is greater than the nitrogen content, and "nitride oxide" refers to a material in which the nitrogen content is greater than the oxygen content. For example, when "silicon oxynitride" is written, it refers to a material in which the oxygen content is greater than the nitrogen content, and when "silicon nitride oxide" is written, it refers to a material in which the nitrogen content is greater than the oxygen content.

[0170] The insulating layer 182a can be formed using sputtering, chemical vapor deposition (CVD), molecular beam epitaxy (MBE), pulsed laser deposition (PLD), atomic layer deposition (ALD), and other methods. The ALD method, which provides good coverage, is preferably used for forming the insulating layer 182a.

[0171] The insulating layer 182b provided on the insulating layer 182a has the function of filling the recesses of the insulating layer 182a and improving the flatness of the insulating layer 182. By improving the flatness of the insulating layer 182, the step coverage of the common electrode 123 formed thereon can be improved. As the insulating layer 182b, an insulating layer having an organic material can be suitably used. For example, as the insulating layer 182b, one or more of acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimidoamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins can be used. Alternatively, a photosensitive resin can be used as the insulating layer 182b. The photosensitive resin can be a positive-type material or a negative-type material. A photoresist may also be used as the photosensitive resin.

[0172] By using a photosensitive resin for the insulating layer 182b, the insulating layer 182b can be manufactured using only the exposure and development processes. Alternatively, the insulating layer 182b may be formed using a negative-type photosensitive resin (e.g., a resist material). Furthermore, when using an insulating layer containing an organic material as the insulating layer 182b, it is preferable to use a material that absorbs visible light. By using a material that absorbs visible light for the insulating layer 182b, the light emitted from the EL layer 175 can be absorbed by the insulating layer 182b, thereby suppressing light (stray light) that may leak into the adjacent EL layer 175. Therefore, a display device with high display quality can be obtained. Similarly, light (stray light) that may leak from the EL layer 175 to the adjacent light-receiving layer 177 can be suppressed. Therefore, a display device with a high signal-to-noise ratio and a highly accurate light-receiving device 150 can be obtained.

[0173] By using a colored material (for example, a material containing black pigment) as the insulating layer 182b, a function may be provided to block stray light from adjacent pixels and suppress color mixing. Alternatively, a reflective film (for example, a metal film containing one or more selected from silver, palladium, copper, titanium, and aluminum) may be provided between the insulating layer 182a and the insulating layer 182b, and the light emitted from the light-emitting layer may be reflected by the reflective film, thereby improving the light extraction efficiency.

[0174] The upper surface of the insulating layer 182b is preferably flat, but the surface may have a gently curved shape. The upper surface of the insulating layer 182b may be, for example, convex, concave, or flat. Alternatively, the upper surface of the insulating layer 182b may have a wavy shape with concave and convex portions, as shown in Figure 5A.

[0175] The insulating layer 182a is provided between the EL layer 175 and the light-receiving layer 177 and the insulating layer 182b, so that they do not come into contact with each other. If the EL layer 175 and the light-receiving layer 177 come into contact with the insulating layer 182b, the components contained in the insulating layer 182b (for example, organic solvents) may cause the EL layer 175 and the light-receiving layer 177 to dissolve. By providing the insulating layer 182a, the sides of the EL layer 175 and the sides of the light-receiving layer 177 can be protected. Note that it is also possible to omit either the insulating layer 182a or the insulating layer 182b, that is, to provide only one of the insulating layer 182a or the insulating layer 182b. For example, as shown in Figure 5B, it is also possible to have a configuration in which the insulating layer 182b is not provided.

[0176] A protective layer 125 is provided on the common electrode 123. The protective layer 125 has the function of preventing impurities such as water from diffusing to each light-emitting device from above.

[0177] The protective layer 125 can be a single-layer structure or a multilayer structure including at least an inorganic insulating film. Examples of inorganic insulating films include oxide films or nitride films such as silicon oxide film, silicon oxide nitride film, silicon nitride film, silicon nitride film, aluminum oxide film, aluminum oxide nitride film, and hafnium oxide film. Alternatively, semiconductor materials such as indium gallium oxide and indium gallium zinc oxide may be used as the protective layer 125.

[0178] A laminated film of an inorganic insulating film and an organic insulating film can also be used as the protective layer 125. For example, it is preferable to have a configuration in which an organic insulating film is sandwiched between a pair of inorganic insulating films. Furthermore, it is preferable that the organic insulating film functions as a planarizing film. This makes the upper surface of the organic insulating film flat, thereby improving the coverage of the inorganic insulating film on top of it and enhancing its barrier properties. In addition, since the upper surface of the protective layer 125 is flat, it is preferable because it reduces the influence of uneven shapes caused by the structure below when a structure (e.g., a color filter, touch sensor electrodes, or lens array, etc.) is provided above the protective layer 125.

[0179] The connection portion 140 has a common electrode 123 and an electrode 111p that is electrically connected to the common electrode 123. The connection portion 140 can be called a cathode contact portion. The electrode 111p can be made of the same material as electrodes 111a, 111b, 111c, and 111d. Also, electrode 111p can be formed by the same process as electrodes 111a, 111b, 111c, and 111d. A protective layer 125 is provided covering the common electrode 123.

[0180] As shown in Figure 4B, an insulating layer 182 may be provided so as to surround the connection portion 140. Preferably, the insulating layer 182 has a region that is in contact with the side surface of the electrode 111p. A common electrode 123 is provided on the insulating layer 182.

[0181] Figure 4A shows an example where the connection portion 140 is located to the right of the display portion in a top view, but the position of the connection portion 140 is not particularly limited. The connection portion 140 only needs to be provided in at least one place 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. Furthermore, there may be one or more connection portions 140.

[0182] The connecting portion 140 can be provided along the outer circumference of the display unit. The connecting portion 140 may be provided along one side of the outer circumference of the display unit, or it may be provided across two or more sides of the outer circumference of the display unit. Furthermore, the shape of the upper surface of the connecting portion 140 is not particularly limited. If the upper surface shape of the display unit is rectangular, the upper surface shape of the connecting portion 140 may be, for example, strip-shaped, L-shaped, bracket-shaped, or quadrilateral.

[0183] Figures 4B, 5A, and 5B show examples where the edges of the EL layer 175 and the light-receiving layer 177 coincide with or roughly coincide with the edges of the electrode 111, but the present invention is not limited to these examples. The edges of the EL layer 175 and the light-receiving layer 177 do not have to coincide with the edges of the electrode 111. As shown in Figure 5C, the edges of the EL layer 175 and the light-receiving layer 177 may be located inside the edges of the electrode 111. As shown in Figure 5D, the edges of the EL layer 175 and the light-receiving layer 177 may be located outside the edges of the electrode 111.

[0184] In this specification, "ends coincide or roughly coincide" means that, when viewed from above, at least a portion of the contours of the stacked layers overlap. This includes, for example, cases where the upper and lower layers are processed with the same mask pattern, or partially with the same mask pattern. However, strictly speaking, the contours may not overlap, and the contour of the upper layer may be located inside the contour of the lower layer, or the contour of the upper layer may be located outside the contour of the lower layer; in this case, it is also referred to as "ends coincide or roughly coincide."

[0185] [Configuration Example 3-2] Figure 6A shows a configuration different from the one shown in Figure 5D. The light-emitting devices 110R, 110G, 110B, and light-receiving device 150 shown in Figure 6A differ from the configuration shown in Figure 5D mainly in that the sides of electrodes 111a, 111b, 111c, 111d, and 111p each have a tapered shape.

[0186] In this specification, a tapered shape refers to a shape in which at least a portion of the side surface of the structure is inclined with respect to the substrate surface. For example, it is preferable to have a region in which the angle between the inclined side surface and the substrate surface (also called the taper angle) is less than 90 degrees.

[0187] Figure 6B shows an enlarged view of region P, indicated by the dashed line in Figure 6A, and Figure 6C shows an enlarged view of region Q. Figure 6B shows the light-emitting device 110B on the left and the light-receiving device 150 on the right. Figure 6C shows the light-emitting device 110R on the left and the light-emitting device 110G on the right.

[0188] It is preferable that the sides of electrodes 111a, 111b, 111c, 111d, and 111p each have a tapered shape. The taper angles of electrodes 111a, 111b, 111c, 111d, and 111p are preferably less than 90 degrees, more preferably 80 degrees or less, more preferably 70 degrees or less, and more preferably 50 degrees or less. By having tapered shapes on the sides of electrodes 111a, 111b, 111c, 111d, and 111p, the step coverage of the layers formed on them (for example, the first functional layer 115 and the third functional layer 155) is improved, and defects such as step breakage or porosity in the layers can be suppressed.

[0189] As shown in Figure 6B, in the light-emitting device 110B, the edges of the first functional layer 115c, the edges of the light-emitting layer 112B, and the edges of the second functional layer 116c coincide or roughly coincide with each other. In other words, the top surfaces of the first functional layer 115c, the light-emitting layer 112B, and the second functional layer 116c coincide or roughly coincide with each other. For example, the first functional layer 115c, the film that will become the light-emitting layer 112B, and the film that will become the second functional layer 116c can be formed by processing them using the same mask. With this configuration, the area of ​​the light-emitting layer 112B can be increased, and the area of ​​the light-emitting region of the light-emitting device 110B can be increased. In other words, a display device with a high aperture ratio can be made.

[0190] As shown in Figure 6C, in the light-emitting device 110R, the edges of the first functional layer 115a, the edges of the light-emitting layer 112R, and the edges of the second functional layer 116a coincide or roughly coincide with each other. In other words, the top shapes of the first functional layer 115a, the light-emitting layer 112R, and the second functional layer 116a coincide or roughly coincide with each other. For example, the first functional layer 115, the light-emitting layer 112, and the second functional layer 116 can be formed by processing the film that will become the first functional layer 115, the film that will become the light-emitting layer 112, and the film that will become the second functional layer 116 using the same mask. The same applies to the light-emitting device 110G.

[0191] As shown in Figure 6B, in the light-receiving device 150, the edges of the third functional layer 155, the active layer 157, and the fourth functional layer 156 coincide or roughly coincide with each other. In other words, the top shapes of the third functional layer 155, the active layer 157, and the fourth functional layer 156 coincide or roughly coincide with each other. For example, the third functional layer 155, the active layer 157, and the fourth functional layer 156 can be formed by processing them using the same mask. With this configuration, the area of ​​the active layer 157 can be increased, and the area of ​​the light-receiving region of the light-receiving device 150 can be increased. In other words, a display device with high-sensitivity light-receiving function can be made.

[0192] In this specification, "matching or roughly matching top surface shapes" means that at least a portion of the contours overlap between stacked layers. For example, this includes cases where the upper and lower layers are processed with the same mask pattern, or partially with the same mask pattern. However, strictly speaking, the contours may not overlap, and the upper layer may be located inside the lower layer, or the upper layer may be located outside the lower layer; in this case, it is also referred to as "matching or roughly matching top surface shapes."

[0193] As shown in Figure 6B, it is preferable that the light-receiving layer 177 of the light-receiving device 150 does not have a layer in common with the EL layer 175B of the light-emitting device 110B, and does not have a region in contact with the EL layer 175B. In other words, it is preferable that the light-receiving layer 177 is separated from the EL layer 175B. Although Figure 6B shows the light-emitting device 110B as a light-emitting device adjacent to the light-receiving device 150, it is not limited to this. It is preferable that the light-receiving layer of a light-receiving device is separated from the EL layer of a light-emitting device adjacent to that light-receiving device. Similarly, when two light-receiving devices are adjacent to each other, it is preferable that the light-receiving layer of one light-receiving device is separated from the light-receiving layer of the other light-receiving device.

[0194] As shown in Figure 6C, it is preferable that the EL layer 175G of the light-emitting device 110G does not have a layer in common with the EL layer 175R of the light-emitting device 110R, and does not have a region in contact with the EL layer 175R. In other words, it is preferable that the EL layer 175G is separated from the EL layer 175R. Note that Figure 6C shows the light-emitting device 110R as a light-emitting device adjacent to the light-emitting device 110G, but is not limited to this. It is preferable that the EL layer of a light-emitting device is separated from the EL layer of that light-emitting device and adjacent light-emitting devices.

[0195] As shown in Figure 6B, in the light-receiving device 150, the side surface of the third functional layer 155 is preferably perpendicular or approximately perpendicular to the surface to be formed. For example, the angle θ between the side surface of the third functional layer 155 and the surface to be formed (in this case, the substrate 101) 155 The temperature is preferably between 60 and 90 degrees.

[0196] As shown in Figure 6B, in the light-emitting device 110B, the side surface of the first functional layer 115c is preferably perpendicular or approximately perpendicular to the surface to be formed. For example, the angle θ between the side surface of the first functional layer 115c and the surface to be formed (in this case, the substrate 101) 115c The temperature is preferably between 60 and 90 degrees.

[0197] Similarly, as shown in Figure 6C, in the light-emitting device 110R, the side surface of the first functional layer 115a is preferably perpendicular or approximately perpendicular to the surface to be formed. For example, the angle θ formed between the side surface of the first functional layer 115a and the surface to be formed (in this case, the substrate 101) 115a The angle is preferably 60 degrees or more and 90 degrees or less. In the light-emitting device 110G, the side surface of the first functional layer 115b is preferably perpendicular or approximately perpendicular to the surface to be formed. For example, the angle θ formed between the side surface of the first functional layer 115b and the surface to be formed (in this case, the substrate 101) 115b The temperature is preferably between 60 and 90 degrees.

[0198] The light-emitting layers 112R, 112G, and 112B can each be formed using FMM. The light-emitting layer 112 formed using FMM may have a thinner thickness towards the edges. As shown in Figure 6B, in the light-emitting device 110B, the film thickness TE at the edge of the light-emitting layer 112B 112B This refers to the film thickness TC in the region inside the said edge. 112B It may become even thinner. Similarly, as shown in Figure 6C, in the light-emitting device 110R, the film thickness TE at the edge of the light-emitting layer 112R 112R This refers to the film thickness TC in the region inside the said edge. 112R It may become even thinner. In the light-emitting device 110G, the film thickness TE at the edge of the light-emitting layer 112G 112G This refers to the film thickness TC in the region inside the said edge. 112G It may become even thinner. Note that the film thickness TE at the edge of the light-emitting layer 112 112R , film thickness TE 112G , and film thickness TE 112B These can be said to be the film thickness of the light-emitting layer 112 in the region where the light-emitting layer 112 and the insulating layer 182 are in contact. On the other hand, the film thickness TC of the light-emitting layer 112 112R , film thickness TC 112G , and film thickness TC 112B These can be said to represent the film thickness of the light-emitting layer 112 in the region where the light-emitting layer 112 and the insulating layer 182 are not in contact.

[0199] The film thicknesses of the light-emitting layer 112R, light-emitting layer 112G, and light-emitting layer 112B may differ from each other. While Figure 6A shows an example where the film thickness of light-emitting layer 112R is thick and the film thickness of light-emitting layer 112B is thin, the relative thicknesses of the light-emitting layers 112R, 112G, and 112B are not limited to this example. Similarly, the relative thicknesses of the active layer 157 and the light-emitting layers 112R, 112G, and 112B are not particularly limited.

[0200] Preferably, the insulating layer 182 has a region that is in contact with the side surface of the EL layer 175 and the side surface of the light-receiving layer 177. By providing the insulating layer 182 in contact with the EL layer 175 and the light-receiving layer 177, the island-shaped EL layer 175 and light-receiving layer 177 are fixed or bonded by the insulating layer 182. This prevents the EL layer 175 and the light-receiving layer 177 from peeling off. This can improve the reliability of the light-emitting device 110 and the light-receiving device 150. Furthermore, it can improve the manufacturing yield of the light-emitting device 110 and the light-receiving device 150.

[0201] Preferably, the height of the upper surface of the insulating layer 182 matches or approximately matches the height of the upper surface at the end of the EL layer 175 and the height of the upper surface at the end of the light-receiving layer 177. By doing so, the surface to which the common electrode 123 is formed can be made flatter, and connection failures due to stepped cuts in the common electrode 123 can be suppressed. Alternatively, it is possible to suppress the local thinning of the film thickness of the common electrode 123 due to the step, which would increase the electrical resistance. Although it is preferable that the upper surface of the insulating layer 182 has a flat shape, it may have convex portions, convex curved surfaces, concave curved surfaces, or recesses.

[0202] The height of the upper surface of the insulating layer 182 may be higher or lower than the height of the upper surface at the end of the EL layer 175 and the height of the upper surface at the end of the light-receiving layer 177. At a minimum, it is preferable that the insulating layer 182 covers the side surfaces of the light-emitting layer 112R and the side surfaces of the active layer 157. In other words, it is preferable that the height of the upper surface of the insulating layer 182 is higher than the height of the upper surface at the end of the light-emitting layer 112 and the height of the upper surface at the end of the active layer 157. By covering the side surfaces of the light-emitting layer 112R and the side surfaces of the active layer 157 with the insulating layer 182, the diffusion of impurities into the light-emitting layer 112R and the active layer 157 can be suppressed.

[0203] Figure 6A and others show a configuration in the light-emitting device 110 where the edge of the EL layer 175 is located outside the edge of the electrode 111, but the present invention is not limited to this. The edge of the EL layer 175 may be located inside the edge of the electrode 111, or it may coincide with or roughly coincide with the edge of the electrode 111. Also, in the EL layer 175, a configuration is shown where the edge of the light-emitting layer 112 coincides with or roughly coincides with the edge of the first functional layer 115 and the edge of the second functional layer 116, but the present invention is not limited to this. The edge of the light-emitting layer 112 may be located inside the edge of the first functional layer 115 and the edge of the second functional layer 116. If the end of the light-emitting layer 112 is located inside the end of the first functional layer 115 and the end of the second functional layer 116, the end of the light-emitting layer 112 may be located inside the end of the electrode 111, outside the end of the electrode 111, or may coincide with or approximately coincide with the end of the electrode 111.

[0204] Figure 6A and others show a configuration in the light-receiving device 150 in which the end of the light-receiving layer 177 is located outside the end of the electrode 111, but the present invention is not limited to this. The end of the light-receiving layer 177 may be located inside the end of the electrode 111, or it may coincide with or approximately coincide with the end of the electrode 111.

[0205] Figure 6(A) shows the sacrificial layer 128p in the connection portion 140, which has a region in contact with the electrode 111p. The sacrificial layer 128p is a remnant of a layer that was provided when the display device was manufactured. Details of the sacrificial layer 128p will be described later.

[0206] [Configuration Example 3-3] Figure 7A shows configurations different from those shown in Figure 6A. The light-emitting devices 110R, 110G, and 110B shown in Figure 7A differ from the configuration shown in Figure 6A mainly in that the edges of the light-emitting layer 112 are located inward from the edges of the first functional layer 115 and the second functional layer 116.

[0207] Figure 7B shows an enlarged view of region P, indicated by the dashed line in Figure 7A, and Figure 7C shows an enlarged view of region Q. Figure 7B shows the light-emitting device 110B on the left and the light-receiving device 150 on the right. Figure 7C shows the light-emitting device 110R on the left and the light-emitting device 110G on the right.

[0208] As shown in Figure 6B, in the light-emitting device 110B, the edge of the light-emitting layer 112B is located inward from the edge of the first functional layer 115c. Also, the edge of the light-emitting layer 112B is located inward from the edge of the second functional layer 116c. The top and side surfaces of the light-emitting layer 112B are in contact with the second functional layer 116c. In other words, the top and side surfaces of the light-emitting layer 112B are covered by the second functional layer 116c. By covering the top and side surfaces of the light-emitting layer 112B with the second functional layer 116c, the diffusion of impurities into the light-emitting layer 112B can be suppressed. Therefore, the reliability of the light-emitting device 110B can be improved. Such impurities include, for example, metallic components contained in the common electrode 123.

[0209] The side surface of the light-emitting layer 112B is preferably tapered. The angle θ formed between the side surface of the light-emitting layer 112B and the surface to be formed (in this case, the first functional layer 115c) 112B It is preferable that it be small. Specifically, angle θ 112BThe angle θ is preferably greater than 0 degrees and less than 90 degrees, more preferably greater than 0 degrees and less than 60 degrees, more preferably greater than 0 degrees and less than 50 degrees, more preferably greater than 0 degrees and less than 40 degrees, and more preferably greater than 0 degrees and less than 30 degrees. 112B By reducing the angle θ, the step coverage of the layer formed on the light-emitting layer 112B and the first functional layer 115c (for example, the second functional layer 116c) is improved, and defects such as step breaks or porosity in the layer can be suppressed. 112B is, angle θ 115c Smaller is preferable.

[0210] The light-emitting layer 112B can be formed using an FMM. The light-emitting layer 112B formed using an FMM becomes thinner towards the edges, and the angle θ 112B In some cases, it can become extremely small. For example, angle θ 112B The temperature can be greater than 0 degrees and less than 30 degrees. As a result, the side and top surfaces of the light-emitting layer 112B may be continuously connected, making it difficult to clearly distinguish between the side and top surfaces.

[0211] The edges of the second functional layer 116c coincide with or roughly coincide with the edges of the first functional layer 115c. In other words, the top surface shape of the second functional layer 116c coincides with or roughly coincides with that of the first functional layer 115c. For example, the first functional layer 115c and the second functional layer 116c can be formed by processing a first film that will become the first functional layer 115c and a second film that will become the second functional layer 116c using the same mask.

[0212] The sides of the first functional layer 115c and the second functional layer 116c are preferably perpendicular or approximately perpendicular to the respective surface to be formed. For example, the angle θ between the side of the first functional layer 115c and the surface to be formed (in this case, the substrate 101) 115c The angle θ is preferably between 60 and 90 degrees. 116c The temperature is preferably between 60 and 90 degrees.

[0213] Although the light-emitting device 110B is used as an example in this explanation, the same applies to the light-emitting device 110R and the light-emitting device 110B. The angle θ formed between the side surface of the light-emitting layer 112R and the surface to be formed (in this case, the first functional layer 115a) 112R , and the angle θ formed between the side surface of the light-emitting layer 112G and the surface to be formed (in this case, the first functional layer 115b) 112G Each of these is the angle θ. 112B Since the description can be found elsewhere, a detailed explanation will be omitted. The angle θ between the side surface of the second functional layer 116a and the surface to be formed (in this case, the first functional layer 115a) 116a , and the angle θ formed between the side surface of the second functional layer 116b and the surface to be formed (in this case, the first functional layer 115b) 116b Each of these is the angle θ. 116c Since you can refer to the information provided, a detailed explanation will be omitted.

[0214] As shown in Figure 7B, in the light-receiving device 150, the edges of the third functional layer 155, the active layer 157, and the fourth functional layer 156 coincide or roughly coincide with each other. In other words, the top shapes of the third functional layer 155, the active layer 157, and the fourth functional layer 156 coincide or roughly coincide with each other. For example, the third functional layer 155, the active layer 157, and the fourth functional layer 156 can be formed by processing the film that will become the third functional layer 155, the film that will become the active layer 157, and the film that will become the fourth functional layer 156 using the same mask.

[0215] The side surface of the third functional layer 155 is preferably perpendicular or approximately perpendicular to the surface to be formed. For example, the angle θ formed between the side surface of the third functional layer 155 and the surface to be formed (in this case, the substrate 101) 155 The temperature is preferably between 60 and 90 degrees.

[0216] [Configuration Example 3-4] Figure 8A shows configurations different from those shown in Figure 7A. The light-emitting devices 110R, 110G, and 110B shown in Figure 8A differ from the configuration shown in Figure 7A mainly in that the edges of the light-emitting layer 112 are located inside the edges of the electrodes 111.

[0217] Figure 8B shows an enlarged view of region P, indicated by the dashed line in Figure 8A, and Figure 8C shows an enlarged view of region Q. Figure 8B shows the light-emitting device 110B on the left and the light-receiving device 150 on the right. Figure 8C shows the light-emitting device 110R on the left and the light-emitting device 110G on the right.

[0218] As shown in Figure 8B, in the photodetector 150, the edges of the third functional layer 155, the active layer 157, and the fourth functional layer 156 coincide or roughly coincide. The edges of the third functional layer 155, the active layer 157, and the fourth functional layer 156 are located outside the edges of the electrode 111d.

[0219] As shown in Figures 8B and 8C, in the light-emitting device 110, the edges of the first functional layer 115 and the second functional layer 116 coincide or roughly coincide. The edges of the first functional layer 115 and the second functional layer 116 are located outside the edge of the electrode 111. The edge of the electrode 111 is located outside the edge of the light-emitting layer 112.

[0220] [Configuration Example 3-5] Figure 9A shows a configuration different from the one shown in Figure 6A. The light-emitting devices 110R, 110G, and 110B shown in Figure 9A differ from the configuration shown in Figure 6A mainly in that the edges of the EL layer 175 are located inside the edges of the electrode 111, and the light-receiving device 150 differs from the configuration shown in Figure 6A mainly in that the edges of the light-receiving layer 177 are located inside the edges of the electrode 111d.

[0221] Figure 9B shows an enlarged view of region P, indicated by the dashed line in Figure 9A, and Figure 9C shows an enlarged view of region Q. Figure 9B shows the light-emitting device 110B on the left and the light-receiving device 150 on the right. Figure 9C shows the light-emitting device 110R on the left and the light-emitting device 110G on the right.

[0222] As shown in Figure 9B, the edge of the light-receiving layer 177 is located on electrode 111d. The edge of the EL layer 175B is located on electrode 111c. As shown in Figure 9C, the edge of the EL layer 175R is located on electrode 111a. The edge of the EL layer 175G is located on electrode 111b.

[0223] Preferably, the insulating layer 182 has regions that are in contact with the side surfaces of the EL layer 175, the side surfaces of the light-receiving layer 177, and the top and side surfaces of the electrode 111. In particular, by providing the insulating layer 182 between the electrode 111 and the common electrode 123, it is possible to suppress contact between the electrode 111 and the common electrode 123 and prevent a short circuit.

[0224] [Configuration Example 3-6] Figure 10A shows configurations different from those shown in Figure 9A. The light-emitting devices 110R, 110G, and 110B shown in Figure 10A differ from the configuration shown in Figure 9A mainly in that the edges of the light-emitting layer 112 are located inside the edges of the first functional layer 115 and the second functional layer 116, respectively.

[0225] Figure 10B shows an enlarged view of region P, indicated by the dashed line in Figure 10A, and Figure 10C shows an enlarged view of region Q. Figure 10B shows the light-emitting device 110B on the left and the light-receiving device 150 on the right. Figure 10C shows the light-emitting device 110R on the left and the light-emitting device 110G on the right.

[0226] As shown in Figure 10B, in the photodetector 150, the edges of the third functional layer 155, the active layer 157, and the fourth functional layer 156 coincide or roughly coincide. The edges of the third functional layer 155, the active layer 157, and the fourth functional layer 156 are located inside the edges of the electrode 111d.

[0227] As shown in FIGS. 10B and 10C, in the light-emitting device 110, the ends of the first functional layer 115 and the second functional layer 116 coincide or substantially coincide. The ends of the first functional layer 115 and the second functional layer 116 are located inside the ends of the electrode 111. The ends of the first functional layer 115 and the second functional layer 116 are located outside the ends of the light-emitting layer 112.

[0228] [Configuration Example 3-7] A configuration different from the configuration shown in FIG. 6A is shown in FIG. 11A. The configuration shown in FIG. 11A is mainly different from the configuration shown in FIG. 6A in that the insulating layer 182 has a region overlapping the upper surfaces of the EL layer 175R, the EL layer 175G, the EL layer 175B, and the light-receiving layer 177.

[0229] An enlarged view of the region P indicated by the dashed-dotted line in FIG. 11A is shown in FIG. 11B, and an enlarged view of the region Q is shown in FIG. 11C. FIG. 11B shows the light-emitting device 110B on the left side and the light-receiving device 150 on the right side. FIG. 11C shows the light-emitting device 110R on the left side and the light-emitting device 110G on the right side.

[0230] As shown in FIG. 11B, the upper surface of the insulating layer 182 has a region higher than the upper surface of the light-receiving layer 177. Also, a sacrificial layer 128 used when forming the light-receiving layer 177 may remain between the insulating layer 182 and the light-receiving layer 177. Details of the sacrificial layer 128 will be described later.

[0231] In a cross-sectional view, one end of the sacrificial layer 128 coincides or substantially coincides with the end of the light-receiving layer 177. The other end of the sacrificial layer 128 coincides or substantially coincides with the end of the insulating layer 182. For example, a first sacrificial layer serving as the sacrificial layer 128 is formed on a film to be the light-receiving layer 177. Subsequently, using the first sacrificial layer as a mask, the film to be the light-receiving layer 177 is processed to form the light-receiving layer 177. Subsequently, a film to be the insulating layer 182a and the insulating layer 182b are formed. Subsequently, by processing the film to be the insulating layer 182a and the first sacrificial layer using the insulating layer 182b as a mask, the insulating layer 182a and the sacrificial layer 128 can be formed.

[0232] The upper surface of the insulating layer 182 has a region higher than the upper surface of the EL layer 175B. Also, a sacrificial layer 118c used when forming the EL layer 175B may remain between the insulating layer 182 and the EL layer 175B.

[0233] One end of the sacrificial layer 118c coincides with or substantially coincides with the end of the EL layer 175B. The other end of the sacrificial layer 118c coincides with or substantially coincides with the end of the insulating layer 182. For example, a second sacrificial layer serving as the sacrificial layer 118c is formed on the film that will become the EL layer 175B. Subsequently, using the second sacrificial layer as a mask, the film that will become the EL layer 175B is processed to form the EL layer 175B. Subsequently, a film that will become the insulating layer 182a and the insulating layer 182b are formed. Subsequently, by processing the film that will become the insulating layer 182a and the second sacrificial layer using the insulating layer 182b as a mask, the insulating layer 182a and the sacrificial layer 118c can be formed. Details of the sacrificial layer 118c will be described later.

[0234] As shown in FIG. 11C, the upper surface of the insulating layer 182 has a region higher than the upper surface of the EL layer 175R. Also, a sacrificial layer 118a used when forming the EL layer 175R may remain between the insulating layer 182 and the EL layer 175R. Similarly, the upper surface of the insulating layer 182 has a region higher than the upper surface of the EL layer 175G. Also, a sacrificial layer 118b used when forming the EL layer 175G may remain between the insulating layer 182 and the EL layer 175G. For the sacrificial layer 118a and the sacrificial layer 118b, since the description of the sacrificial layer 118c can be referred to, detailed description is omitted.

[0235] [Configuration Example 3-8] A configuration different from the configuration shown in FIG. 7A is shown in FIG. 12A. The configuration shown in FIG. 12A is mainly different from the configuration shown in FIG. 7A in that the insulating layer 182 has a region overlapping the upper surfaces of the EL layer 175R, the EL layer 175G, the EL layer 175B, and the light receiving layer 177.

[0236] Figure 12B shows an enlarged view of region P, indicated by the dashed line in Figure 12A, and Figure 12C shows an enlarged view of region Q. Figure 12B shows the light-emitting device 110B on the left and the light-receiving device 150 on the right. Figure 12C shows the light-emitting device 110R on the left and the light-emitting device 110G on the right.

[0237] As shown in Figure 12B, the upper surface of the insulating layer 182 has a region that is higher than the upper surface of the light-receiving layer 177. In addition, the sacrificial layer 128 used when forming the light-receiving layer 177 may remain between the insulating layer 182 and the light-receiving layer 177.

[0238] As shown in Figures 12B and 12C, the upper surface of the insulating layer 182 has a region that is higher than the upper surface of the EL layer 175. In addition, sacrificial layers 118a, 118b, and 118c used when forming EL layers 175R, 175G, and 175B may remain between the insulating layer 182 and EL layers 175R, 175G, and 175B.

[0239] [Configuration Example 3-9] Figure 13A shows a configuration different from the one shown in Figure 6A. The light-emitting devices 110R, 110G, and 110B shown in Figure 13A differ from the configuration shown in Figure 6A mainly in that they have a first functional layer 115 instead of the first functional layers 115a, 115b, and 115c, and a second functional layer 116 instead of the second functional layers 116a, 116b, and 116c.

[0240] Specifically, the light-emitting device 110R has a first functional layer 115, a light-emitting layer 112R, and a second functional layer 116 stacked in this order as an EL layer. The light-emitting device 110G has a first functional layer 115, a light-emitting layer 112G, and a second functional layer 116 stacked in this order as an EL layer. The light-emitting device 110B has a first functional layer 115, a light-emitting layer 112B, and a second functional layer 116 stacked in this order as an EL layer.

[0241] The first functional layer 115 is a layer common to the light-emitting devices 110R, 110G, and 110B, and can be called the first common layer. Similarly, the second functional layer 116 can be called the second common layer. The first functional layer 115 can use the same material as the first functional layer 115a, the first functional layer 115b, and the first functional layer 115c. The second functional layer 116 can use the same material as the second functional layer 116a, the second functional layer 116b, and the second functional layer 116c.

[0242] Figure 13B shows an enlarged view of region P, indicated by the dashed line in Figure 13A, and Figure 13C shows an enlarged view of region Q. Figure 13B shows the light-emitting device 110B on the left and the light-receiving device 150 on the right. Figure 13C shows the light-emitting device 110R on the left and the light-emitting device 110G on the right.

[0243] As shown in Figure 13B, it is preferable that the light-receiving layer 177 of the light-receiving device 150 does not have a layer in common with the EL layer 175B of the light-emitting device 110B, and does not have a region in contact with the EL layer 175B. In other words, it is preferable that the light-receiving layer 177 of the light-receiving device 150 is separated from the EL layer 175 of the light-emitting device 110 adjacent to the light-receiving device 150. Similarly, when two light-receiving devices 150 are adjacent, it is preferable that the light-receiving layer 177 of one light-receiving device 150 is separated from the light-receiving layer 177 of the other light-receiving device 150.

[0244] As shown in Figure 13B, the edges of the second functional layer 116 coincide with or roughly coincide with the edges of the first functional layer 115. In other words, the top surface shape of the second functional layer 116 coincides with or roughly coincides with that of the first functional layer 115. For example, the first functional layer 115 and the second functional layer 116 can be formed by processing a first film that will become the first functional layer 115 and a second film that will become the second functional layer 116 using the same mask.

[0245] The sides of the first functional layer 115 are preferably perpendicular or approximately perpendicular to the respective surface to be formed. For example, the angle θ between the side of the first functional layer 115 and the surface to be formed (in this case, the substrate 101) 115 The temperature is preferably between 60 and 90 degrees.

[0246] As shown in Figures 13A, 13B, and 13C, adjacent light-emitting devices 110 share a first functional layer 115 and a second functional layer 116. Specifically, light-emitting layers 112R, 112G, and 112B share a first functional layer 115 and a second functional layer 116 with the adjacent light-emitting layer 112.

[0247] [Configuration Example 3-10] Figure 14A shows a configuration different from that shown in Figure 13A. The light-emitting devices 110R, 110G, and 110B shown in Figure 14A differ from the configuration shown in Figure 13A mainly in that they have regions where adjacent light-emitting layers 112 overlap.

[0248] An enlarged view of region Q, indicated by the dashed line in Figure 14A, is shown in Figure 14B, and an enlarged view of region R is shown in Figure 14C. Figure 14B shows light-emitting device 110R on the left and light-emitting device 110G on the right. Figure 14C shows light-emitting device 110G on the left and light-emitting device 110B on the right. An enlarged view of region P can be found in Figure 13B.

[0249] As shown in Figure 14B, the light-emitting layer 112G has a region that overlaps with the light-emitting layer 112R. Specifically, the light-emitting layer 112G is provided covering the light-emitting layer 112R and has a region that is in contact with the edge of the light-emitting layer 112R. Similarly, as shown in Figure 14C, the light-emitting layer 112B has a region that overlaps with the light-emitting layer 112G. Specifically, the light-emitting layer 112B is provided covering the light-emitting layer 112G and has a region that is in contact with the edge of the light-emitting layer 112G.

[0250] Figure 14A and others show a configuration in which the light-emitting layer 112R, light-emitting layer 112G, and light-emitting layer 112B are formed in this order, with light-emitting layer 112B covering light-emitting layer 112G and light-emitting layer 112G covering light-emitting layer 112R. However, the present invention is not limited to this configuration. The order in which the light-emitting layers 112R, 112G, and 112B are formed is not particularly limited, and a configuration can be made in which adjacent light-emitting layers 112 have overlapping regions. The presence of overlapping regions between two adjacent light-emitting layers 112 can be confirmed, for example, using the photoluminescence (PL) method.

[0251] In regions overlapping with electrode 111, it is preferable that adjacent light-emitting layers 112 do not overlap. In other words, it is preferable that regions where adjacent light-emitting layers 112 overlap do not overlap with electrode 111. In regions where adjacent light-emitting layers 112 overlap, the total thickness of the light-emitting layers 112 increases, which can lead to a higher driving voltage and a reduced contribution to light emission. By configuring the adjacent light-emitting layers 112 not to overlap in regions overlapping with electrode 111, it is possible to suppress the reduction in the area of ​​the light-emitting region.

[0252] Between adjacent light-emitting devices 110, a step difference occurs near the edge of the light-emitting layer 112 between the region where the light-emitting layer 112 is provided and the region where the light-emitting layer 112 is not provided. In one embodiment of the present invention, the display device has a region where adjacent light-emitting layers 112 overlap, thereby reducing this step difference and improving the step-coverage of the second functional layer 116 formed thereon. Therefore, step breaks in the second functional layer 116 can be suppressed.

[0253] Figure 14A and others show a configuration in which an insulating layer 182 is provided between the light-receiving layer 177 and the adjacent EL layer 175, and an insulating layer 182 is not provided between two adjacent EL layers 175. However, the present invention is not limited to this. An insulating layer 182 may also be provided between two adjacent EL layers 175. Furthermore, when separating the first functional layer 115 and the second functional layer 116 between two adjacent light-emitting devices 110, the area where the adjacent light-emitting layers 112 are in contact may be removed, or a portion thereof may be removed.

[0254] [Configuration Example 3-11] A configuration different from the configuration shown in FIG. 6A is shown in FIG. 15A. The configuration shown in FIG. 15A is mainly different from the configuration shown in FIG. 6A in that it does not have the insulating layer 182.

[0255] An enlarged view of the region P indicated by the dashed-dotted line in FIG. 15A is shown in FIG. 15B, and an enlarged view of the region Q is shown in FIG. 15C. FIG. 15B shows the light-emitting device 110B on the left side and the light-receiving device 150 on the right side. FIG. 15C shows the light-emitting device 110R on the left side and the light-emitting device 110G on the right side.

[0256] As shown in FIGS. 15B and 15C, it is preferable that the side surfaces of the electrodes 111a, 111b, and 111c are each covered with one or more of the first functional layer 115, the light-emitting layer 112, and the second functional layer 116. That is, it is preferable that the ends of the electrodes 111a, 111b, and 111c are each located inside one or more of the ends of the first functional layer 115, the ends of the light-emitting layer 112, and the ends of the second functional layer 116. Similarly, it is preferable that the side surface of the electrode 111d is covered with one or more of the third functional layer 155, the active layer 157, and the fourth functional layer 156. That is, it is preferable that the end of the electrode 111d is located inside one or more of the ends of the third functional layer 155, the ends of the active layer 157, and the ends of the fourth functional layer 156. By adopting such a configuration, it is possible to suppress the short circuit caused by the contact between the electrode 111 and the common electrode 123.

[0257] [Configuration Example 3-12] A configuration different from the configuration shown in FIG. 13A is shown in FIG. 16A. The light-emitting devices 110R, 110G, and 110B shown in FIG. 16A are mainly different from the configuration shown in FIG. 13A in that the shapes of the side surfaces of the first functional layer 115 and the second functional layer 116 are different.

[0258] Figure 16B shows an enlarged view of region P, indicated by the dashed line in Figure 16A, and Figure 16C shows an enlarged view of region Q. Figure 16B shows the light-emitting device 110B on the left and the light-receiving device 150 on the right. Figure 16C shows the light-emitting device 110R on the left and the light-emitting device 110G on the right.

[0259] The side surface of the first functional layer 115 has a tapered shape. The angle θ formed between the side surface of the first functional layer 115 and the surface to be formed (in this case, the substrate 101) 115 It is preferable that it be small. Specifically, angle θ 115 The angle θ is preferably greater than 0 degrees and less than 90 degrees, more preferably greater than 0 degrees and less than 60 degrees, more preferably greater than 0 degrees and less than 50 degrees, more preferably greater than 0 degrees and less than 40 degrees, and more preferably greater than 0 degrees and less than 30 degrees. 115 By reducing the step coverage of the layer formed on the substrate 101 and the first functional layer 115 (for example, the insulating layer 182), the step coverage is improved, and defects such as step breaks or porosity in the layer can be suppressed. The side surface of the second functional layer 116 may also have a tapered shape. By having a tapered shape on the side surface of the second functional layer 116, the step coverage of the layer formed on the first functional layer 115 and the second functional layer 116 (for example, the insulating layer 182) is improved, and defects such as step breaks or porosity in the layer can be suppressed.

[0260] As shown in Figure 16B, the end of the second functional layer 116 is located inside the end of the first functional layer 115. Alternatively, the end of the second functional layer 116 may be located outside the end of the first functional layer 115, and may coincide with or approximately coincide with the end of the first functional layer 115.

[0261] Although Figure 16A and others show a configuration in which the edge of the light-emitting layer 112 is located inside the edges of the first functional layer 115 and the second functional layer 116, the present invention is not limited to this. The edge of the light-emitting layer 112 may be located outside the edge of the first functional layer 115. The edge of the light-emitting layer 112 may be located outside the edge of the second functional layer 116.

[0262] [Configuration Example 3-13] Figure 17A shows a configuration different from the one shown in Figure 16A. The configuration shown in Figure 17A differs from the configuration shown in Figure 16A mainly in that it does not have an insulating layer 182.

[0263] Figure 17B shows an enlarged view of region P, indicated by the dashed line in Figure 17A, and Figure 17C shows an enlarged view of region Q. Figure 17B shows the light-emitting device 110B on the left and the light-receiving device 150 on the right. Figure 17C shows the light-emitting device 110R on the left and the light-emitting device 110G on the right.

[0264] As shown in Figures 17B and 17C, it is preferable that the sides of electrodes 111a, 111b, and 111c are covered with one or more of the first functional layer 115, the light-emitting layer 112, and the second functional layer 116. In other words, it is preferable that the ends of electrodes 111a, 111b, and 111c are located inside one or more of the ends of the first functional layer 115, the light-emitting layer 112, and the second functional layer 116. Similarly, it is preferable that the sides of electrode 111d are covered with one or more of the third functional layer 155, the active layer 157, and the fourth functional layer 156. In other words, it is preferable that the end of electrode 111d is located inside one or more of the ends of the third functional layer 155, the active layer 157, and the fourth functional layer 156. With this configuration, it is possible to suppress contact between electrode 111 and the common electrode 123 and short circuit.

[0265] <Example of manufacturing method 1> In the following, an example of a method for manufacturing a display device according to one embodiment of the present invention will be described with reference to the drawings. Here, the method for manufacturing the display device shown in Figure 6A will be used as an example. Figures 18A to 21D are schematic cross-sectional views of each step in the method for manufacturing the display device.

[0266] Furthermore, thin films (insulating films, semiconductor films, conductive films, etc.) that constitute the display device can be formed using methods such as sputtering, chemical vapor deposition (CVD), vacuum deposition, pulsed laser deposition (PLD), and atomic layer deposition (ALD). CVD methods include plasma-enhanced CVD (PECVD) and thermal CVD. One type of thermal CVD method is metal-organic CVD (MOCVD).

[0267] Thin films (insulating films, semiconductor films, conductive films, etc.) that constitute a display device can be formed by methods such as spin coating, dip coating, spray coating, inkjet printing, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, and knife coating.

[0268] When processing the thin films that constitute the display device, photolithography or the like can be used. Alternatively, the thin films may be processed by nanoimprint lithography, sandblasting, lift-off lithography, or the like.

[0269] 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.

[0270] 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, X-rays, etc., may be used as the light for exposure. An electron beam can also be used instead of the light used for exposure. Using extreme ultraviolet light, X-rays, or an electron beam is preferable because it enables extremely fine processing. Note that a photomask is not required when exposure is performed by scanning a beam such as an electron beam.

[0271] For etching thin films, methods such as dry etching, wet etching, and sandblasting can be used.

[0272] [Formation of electrodes 111a to 111d and electrode 111p] Electrodes 111a, 111b, 111c, 111d, and 111p are formed on the substrate 101 (Figure 18A). First, a conductive film is deposited, a resist mask is formed by photolithography, and unnecessary parts of the conductive film are removed by etching. Then, by removing the resist mask, electrodes 111a, 111b, 111c, 111d, and 111p can be formed.

[0273] When using a conductive film that is reflective to visible light for each pixel electrode, it is preferable to use a material (for example, silver or aluminum) that has the highest possible reflectivity across the entire wavelength range of visible light. This not only improves the light extraction efficiency of the light-emitting device but also enhances color reproduction.

[0274] It is preferable that the sides of electrodes 111a, 111b, 111c, 111d, and 111p each have a tapered shape. It is also preferable that the sides of the resist mask used to form electrodes 111a, 111b, 111c, 111d, and 111p have a tapered shape. Wet etching is preferably used for etching the conductive film.

[0275] [Formation of functional membrane 155f, active membrane 157f, and functional membrane 156f] Next, a functional film 155f, which will later become the third functional layer 155, an active film 157f, which will become the active layer 157, and a functional film 156f, which will become the fourth functional layer 156, are deposited on electrodes 111a, 111b, 111c, and 111d in that order. The functional film 155f, active film 157f, and functional film 156f can each be formed by, for example, vapor deposition, sputtering, coating, or inkjet. However, the above-described film formation methods can be used as appropriate. In this specification, the functional film 155f, active film 157f, and functional film 156f may be collectively referred to as the photodetector film.

[0276] For example, when fabricating a photodetector sensitive to infrared light wavelengths, a photodetector with good properties can be produced by forming at least one of the functional film 155f, the active film 157f, and the functional film 156f using a polymer compound by a coating method or an inkjet method.

[0277] It is preferable that the functional film 155f, the active film 157f, and the functional film 156f are formed so as not to be present on the electrode 111p. For example, when the functional film 155f, the active film 157f, and the functional film 156f are formed by vapor deposition or sputtering, a shielding mask can be used to prevent the functional film 155f, the active film 157f, and the functional film 156f from being deposited on the electrode 111p.

[0278] [Formation of sacrificial film 128f and sacrificial film 129f] Next, a sacrificial film 128f and a sacrificial film 129f are formed on the functional film 156f in that order (Figure 18B). The sacrificial film 128f is provided in contact with the upper surface of the electrode 111p.

[0279] The sacrificial film 128f can preferably be a film with high resistance to etching of the functional film 156f, the active film 157f, and the functional film 155f, i.e., a film with a high etching selectivity ratio. Furthermore, the sacrificial film 128f can preferably be a film with a high etching selectivity ratio with respect to the sacrificial film 129f, which will be described later. Moreover, it is particularly preferable that the sacrificial film 128f be a film that can be removed by a wet etching method that causes less damage to the functional film 156f, the active film 157f, and the functional film 155f.

[0280] The sacrificial film 128f can be, for example, a metal film, an alloy film, a metal oxide film, a semiconductor film, or an inorganic film such as an inorganic insulating film. The sacrificial film 128f can be formed by various film deposition methods such as sputtering, vapor deposition, CVD, and ALD. In particular, since the ALD method causes little film deposition damage to the layer to be formed, it is preferable to form the sacrificial film 128f directly on the functional film 156f using the ALD method.

[0281] The sacrificial film 128f 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. In particular, it is preferable to use a low-melting-point material such as aluminum or silver.

[0282] The sacrificial film 128f can be made of metal oxides such as indium gallium zinc oxide (In-Ga-Zn oxide, also written as IGZO). Furthermore, indium oxide, indium zinc oxide (In-Zn oxide), indium tin oxide (In-Sn oxide, also written as ITO), 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.

[0283] Furthermore, the above-mentioned method can also be applied when element M (where M is one or more selected from aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium) is used instead of gallium. In particular, it is preferable that element M be one or more selected from gallium, aluminum, or yttrium.

[0284] The sacrificial film 128f can be an oxide such as aluminum oxide, hafnium oxide, or silicon oxide; a nitride such as silicon nitride or aluminum nitride; or an oxynitride such as silicon oxynitride. Such inorganic insulating materials can be formed using sputtering, CVD, or ALD methods.

[0285] It is preferable to use a material that is soluble in a chemically stable solvent relative to at least the functional film 156f as the sacrificial film 128f. In particular, a material soluble in water or alcohol can be suitably used for the sacrificial film 128f. When forming the sacrificial film 128f, it is preferable to apply it using a wet deposition method while dissolved in a solvent such as water or alcohol, and then perform a heat treatment to evaporate the solvent. At this time, performing the heat treatment under a reduced pressure atmosphere is preferable because it allows the solvent to be removed at a low temperature and in a short time, thereby reducing thermal damage to the functional film 156f, the activated film 157f, and the functional film 155f.

[0286] Wet film deposition methods that can be used to form the sacrificial film 128f include, for example, spin coating, dip coating, spray coating, inkjet printing, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, and knife coating.

[0287] The sacrificial film 128f can be made of organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin.

[0288] The sacrificial film 129f is used as a hard mask when etching the sacrificial film 128f later. Also, when processing the sacrificial film 129f later, the sacrificial film 128f will be exposed. Therefore, the sacrificial film 128f and the sacrificial film 129f are selected as a combination of films with a high etching selectivity ratio for each other. Thus, the film that can be used for the sacrificial film 129f can be selected according to the etching conditions of the sacrificial film 128f and the sacrificial film 129f.

[0289] For example, when dry etching using a fluorine-containing gas (also called a fluorine-based gas) is used to etch the sacrificial film 129f, silicon, silicon nitride, silicon oxide, tungsten, titanium, molybdenum, tantalum, tantalum nitride, an alloy containing molybdenum and niobium, or an alloy containing molybdenum and tungsten can be used for the sacrificial film 129f. Here, metal oxide films such as IGZO and ITO can be used for the sacrificial film 128f as films that allow for a higher selectivity ratio for etching (i.e., a slower etching rate) compared to the dry etching using the above-mentioned fluorine-based gas.

[0290] However, the sacrificial film 129f can be selected from a variety of materials, depending on the etching conditions of the sacrificial film 128f and the sacrificial film 129f. For example, it can be selected from among the films that can be used for the sacrificial film 128f.

[0291] For example, an oxide film can be used as the sacrificial film 129f. Typically, oxide films or oxynitride films such as silicon oxide, silicon oxynitride, aluminum oxide, aluminum oxynitride, hafnium oxide, and hafnium oxynitride can be used.

[0292] The sacrificial film 129f can be, for example, a nitride film. Specifically, nitrides such as silicon nitride, aluminum nitride, hafnium nitride, titanium nitride, tantalum nitride, tungsten nitride, gallium nitride, and germanium nitride can be used. Alternatively, metals such as tungsten, molybdenum, copper, aluminum, titanium, and tantalum, or alloys containing such metals, may be used as the sacrificial film 129f.

[0293] For example, it is preferable to use an inorganic insulating material such as aluminum oxide, hafnium oxide, or silicon oxide formed by the ALD method as the sacrificial film 128f, and to use an indium-containing metal oxide such as indium gallium zinc oxide (In-Ga-Zn oxide, also written as IGZO) formed by the sputtering method as the sacrificial film 129f.

[0294] For example, the sacrificial film 129f can be made from the same material used for the functional film 155f, the active film 157f, or the functional film 156f. Using such a material is preferable because it allows for the common use of the film deposition apparatus. Furthermore, when etching the functional film 155f, the active film 157f, and the functional film 156f later using the sacrificial layer as a mask, the sacrificial film 129f can also be removed, simplifying the process.

[0295] [Formation of Sacrificial Layer 129 and Sacrificial Layer 128] Next, a resist mask 133 and a resist mask 133p are formed on the sacrificial film 129f in the region overlapping with electrode 111d, and on the sacrificial film 129f in the region overlapping with connection portion 140 (Figure 18C).

[0296] The resist mask 133 and resist mask 133p can use a resist material containing a photosensitive resin, such as a positive-type resist material or a negative-type resist material.

[0297] In this case, if the resist mask 133 and resist mask 133p are formed on the sacrificial film 128f without forming the sacrificial film 129f, there is a risk that the functional film 156f, etc., may dissolve due to the solvent of the resist material if defects such as pinholes exist in the sacrificial film 128f. Using the sacrificial film 129f prevents such problems from occurring.

[0298] Furthermore, if a film less prone to defects such as pinholes is used for the sacrificial film 128f, the resist mask 133 and resist mask 133p may be formed directly on the sacrificial film 128f without using the sacrificial film 129f.

[0299] Next, the sacrificial film 129f in the area not covered by the resist mask 133 and resist mask 133p is removed by etching to form the sacrificial layer 129 and the sacrificial layer 129p.

[0300] When etching the sacrificial film 129f, it is preferable to use etching conditions with a high selectivity ratio so that the sacrificial film 128f is not removed by the etching. The sacrificial film 129f can be etched by wet etching or dry etching, but by using dry etching, it is possible to suppress the reduction in the area of ​​the sacrificial layers 129 and 129p.

[0301] Next, resist mask 133 and resist mask 133p are removed (Figure 18D).

[0302] The resist mask 133 and resist mask 133p can be removed by wet etching or dry etching. In particular, it is preferable to remove the resist mask 133 and resist mask 133p by dry etching (also called plasma ashing) using oxygen gas as the etching gas.

[0303] In this case, the removal of the resist mask 133 is performed with the sacrificial film 128f on the functional film 156f, thus suppressing damage to the functional film 156f, the active film 157f, and the functional film 155f. In particular, since contact of the active film 157f with oxygen can adversely affect the characteristics of the photodetector, this method is suitable when etching is performed using oxygen gas, such as plasma ashing.

[0304] Next, using sacrificial layers 129 and 129p as a mask, the sacrificial film 128f in the region not covered by either sacrificial layer 129 or 129p is removed by etching, forming a sacrificial layer 128 in the region overlapping with electrode 111d, and forming a sacrificial layer 128p in contact with the upper surface of electrode 111p.

[0305] The sacrificial layer 128f can be etched by wet etching or dry etching, but dry etching is preferred because it suppresses the reduction in the area of ​​the sacrificial layer 128 and the sacrificial layer 128p.

[0306] [Formation of the third functional layer 155, the active layer 157, and the fourth functional layer 156] Next, the sacrificial layer 129 and sacrificial layer 129p are removed by etching, and the functional film 156f, active film 157f, and functional film 155f in the regions not covered by either the sacrificial layer 128 or sacrificial layer 128p are removed by etching to form the fourth functional layer 156, the active layer 157, and the third functional layer 155 (Figure 18E).

[0307] By etching the functional film 156f, the active film 157f, and the functional film 155f with the sacrificial layer 129 in the same process, the process can be simplified, increasing the productivity of the display device and reducing manufacturing costs.

[0308] In particular, dry etching using an etching gas that does not contain oxygen (O2) is preferable for etching the functional film 156f, the active film 157f, and the functional film 155f. This suppresses deterioration of the functional film 156f, the active film 157f, and the functional film 155f, enabling the realization of a highly reliable display device. As the etching gas, noble gases such as CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, H2, or He can be suitably used. Alternatively, a mixed gas of the above gases with a gas other than oxygen can be used as the etching gas.

[0309] The etching of the functional film 156f, the active film 157f, and the functional film 155f may be performed separately from the etching of the sacrificial layer 129. For example, the functional film 156f, the active film 157f, and the functional film 155f may be etched first, and then the sacrificial layer 129 may be etched.

[0310] [Formation of functional film 115f] Next, the functional film 115f is formed by covering the substrate 101, electrodes 111a, 111b, 111c, the third functional layer 155, the active layer 157, the fourth functional layer 156, the sacrificial layer 128, and the sacrificial layer 128p (Figure 19A). The functional film 115f later becomes the first functional layer 115a, the first functional layer 115b, and the first functional layer 115c. It is preferable to form the functional film 115f without using FMM.

[0311] The functional film 115f can be deposited using the same method as that used for depositing the functional film 155f, the active film 157f, and the functional film 156f. However, it is not limited to this, and the above-mentioned deposition methods can be used as appropriate.

[0312] [Formation of light-emitting layer 112R, light-emitting layer 112G, and light-emitting layer 112B] Next, an island-shaped light-emitting layer 112R is formed on the functional film 115f in the region overlapping with electrode 111a (Figure 19B).

[0313] The light-emitting layer 112R is preferably formed by a vacuum deposition method using an FMM. Alternatively, island-shaped light-emitting layers 112R may be formed using a sputtering method or an inkjet method using an FMM.

[0314] Figure 19B shows the formation of the light-emitting layer 112R via FMM191R. In Figure 19B, the light-emitting layer 112R is formed using a so-called face-down method, where the substrate is inverted so that the surface to be formed on the light-emitting layer 112R is facing downwards.

[0315] In vacuum deposition using an FMM, deposition often occurs over an area wider than the FMM's opening. As shown by the dashed line in Figure 19B, the light-emitting layer 112R can be deposited over an area wider than the opening of the FMM 191R. Furthermore, the edges of the light-emitting layer 112R are tapered.

[0316] Figure 19B shows a configuration in which the FMM191R does not contact the surface of the light-emitting layer 112R, but the present invention is not limited to this. The FMM191R may contact the surface of the light-emitting layer 112R (in this case, the functional film 115f). In this case, the region that becomes the light-receiving device 150 with the highest height from the substrate 101, that is, the region that overlaps with the electrode 111d, contacts the FMM191R. This region can have the function of holding the FMM191R. Furthermore, this region can have the function of maintaining the distance between the FMM191R and the electrodes 111a, 111b, and 111c. The same applies when forming the light-emitting layers 112G and 112B.

[0317] Next, using FMM191G, a light-emitting layer 112G is formed on the functional film 115f in the region overlapping with the electrode 111b (Figure 19C). The edges of the light-emitting layer 112G are tapered. Although Figure 19C shows an example in which the light-emitting layer 112G does not have a region overlapping with the light-emitting layer 112R, that is, the light-emitting layer 112G and the light-emitting layer 112R are separated, the present invention is not limited to this. The light-emitting layer 112G may also be formed in such a way that it has a region overlapping with the light-emitting layer 112R, that is, the light-emitting layer 112G and the light-emitting layer 112R are in contact.

[0318] Next, using FMM191B, a light-emitting layer 112B is formed on the functional film 115f in the region overlapping with the electrode 111c (Figure 19D). The edges of the light-emitting layer 112B are tapered. Although Figure 19D shows an example in which the light-emitting layer 112B does not have a region overlapping with the light-emitting layer 112G, that is, the light-emitting layer 112B and the light-emitting layer 112G are separated, the present invention is not limited to this. The light-emitting layer 112B may also be formed in such a way that it has a region overlapping with the light-emitting layer 112G, that is, the light-emitting layer 112B and the light-emitting layer 112G are in contact.

[0319] It is preferable not to form the light-emitting layer 112R, light-emitting layer 112G, and light-emitting layer 112B on the electrode 111p.

[0320] In this example, the light-emitting layers 112R, 112G, and 112B were formed in that order, but the formation order is not limited to this.

[0321] [Formation of functional film 116f, sacrificial film 118f, and sacrificial film 119f] Next, the light-emitting layer 112R, light-emitting layer 112G, light-emitting layer 112B, and functional film 115f are covered to form a functional film 116f. The functional film 116f later becomes the second functional layer 116a, the second functional layer 116b, and the second functional layer 116c. The formation of the functional film 116f can be done using the same method as used for forming the functional film 155f, the active film 157f, and the functional film 156f. However, it is not limited to this, and the above-mentioned film formation methods can be used as appropriate.

[0322] Next, a sacrificial film 118f and a sacrificial film 119f are formed on the functional film 116f in that order (Figure 20A).

[0323] The sacrificial film 118f can preferably be a film with high resistance to etching of the functional films 116f and 115f, i.e., a film with a high etching selectivity ratio. Furthermore, the sacrificial film 118f can preferably be a film with a high etching selectivity ratio with respect to the sacrificial film 119f, which will be described later. Additionally, the sacrificial film 118f can be a film that can be removed by a wet etching method that causes minimal damage to the functional films 156f and 155f.

[0324] The sacrificial film 118f can be made from a material that can be used for the sacrificial film 128f. Furthermore, the sacrificial film 118f can be formed using a method that can be used for the formation of the sacrificial film 128f. However, this is not limited to this, and the above-described film formation methods can be used as appropriate.

[0325] It is preferable that the sacrificial film 118f is made of the same material as the sacrificial film 128f. Furthermore, it is preferable that the thickness of the sacrificial film 118f be approximately the same as the thickness of the sacrificial film 128f.

[0326] The sacrificial film 119f is used as a hard mask when etching the sacrificial film 118f later. Also, when processing the sacrificial film 119f later, the sacrificial film 118f will be exposed. Therefore, the sacrificial film 118f and the sacrificial film 119f are selected as a combination of films with a high selectivity ratio for etching each other. Thus, the film that can be used for the sacrificial film 119f can be selected according to the etching conditions of the sacrificial film 118f and the sacrificial film 119f.

[0327] The sacrificial film 119f can be made from the same material as the sacrificial film 129f. The sacrificial film 118f can be formed using the same method as the sacrificial film 128f. However, this is not limited to the above, and the above-described film formation methods can be used as appropriate. The sacrificial film 119f may be made from the same material as the sacrificial film 129f, or from a different material. Furthermore, the film thickness of the sacrificial film 118f may be similar to that of the sacrificial film 128f, or it may be different.

[0328] The etching of sacrificial film 119f is described in the same way as the etching of sacrificial film 129f, so a detailed explanation is omitted.

[0329] [Formation of sacrificial layers 119a to 119c and sacrificial layers 118a to 118c] Next, resist masks 134a, 134b, and 134c are formed on the sacrificial film 119f in the region overlapping with electrode 111a, on the sacrificial film 119f in the region overlapping with electrode 111b, and on the sacrificial film 119f in the region overlapping with electrode 111c (Figure 20B).

[0330] The resist mask 134a is smaller than the light-emitting layer 112R. That is, the edges of the resist mask 134a are located inside the edges of the light-emitting layer 112R. Similarly, the resist mask 134b is smaller than the light-emitting layer 112G. That is, the edges of the resist mask 134b are located inside the edges of the light-emitting layer 112G. The resist mask 134c is smaller than the light-emitting layer 112B. That is, the edges of the resist mask 134c are located inside the edges of the light-emitting layer 112B.

[0331] Detailed explanations of resist masks 134a, 134b, and 134c are omitted as they can be found in the description of resist mask 133.

[0332] When manufacturing the display device shown in Figure 7A, the resist mask 134a is made larger than the light-emitting layer 112R. That is, the edge of the resist mask 134a is located outside the edge of the light-emitting layer 112R. Similarly, the resist mask 134b is made larger than the light-emitting layer 112G. That is, the edge of the resist mask 134b is located outside the edge of the light-emitting layer 112G. The resist mask 134c is made larger than the light-emitting layer 112B. That is, the edge of the resist mask 134c is located outside the edge of the light-emitting layer 112B.

[0333] In this case, if resist masks 134a, 134b, and 134c are formed on the sacrificial film 118f without forming the sacrificial film 119f, there is a risk that the functional film 116f, etc., may dissolve due to the solvent of the resist material if defects such as pinholes exist in the sacrificial film 118f. Using the sacrificial film 119f prevents such problems from occurring.

[0334] Furthermore, if a film less prone to defects such as pinholes is used for the sacrificial film 118f, the resist masks 134a, 134b, and 134c may be formed directly on the sacrificial film 118f without using the sacrificial film 119f.

[0335] Next, the sacrificial film 119f in the region not covered by any of the resist masks 134a, 134b, and 134c is removed by etching to form sacrificial layers 119a, 119b, and 119c.

[0336] When etching the sacrificial film 119f, it is preferable to use etching conditions with a high selectivity ratio so that the sacrificial film 118f is not removed by the etching. The sacrificial film 119f can be etched by wet etching or dry etching, but by using dry etching, it is possible to suppress the reduction in the area of ​​the sacrificial layers 119a, 119b, and 119c.

[0337] Next, resist masks 134a, 134b, and 134c are removed (Figure 20C).

[0338] The removal of resist masks 134a, 134b, and 134c can be performed using the same method as for removing resist mask 133.

[0339] In this case, the removal of the resist masks 134a, 134b, and 134c is performed with the sacrificial film 118f on the functional film 116f, thus suppressing damage to the functional film 156f, the light-emitting layer 112R, the light-emitting layer 112G, the light-emitting layer 112B, and the functional film 155f. In particular, since contact between the light-emitting layer 112R, the light-emitting layer 112G, and the light-emitting layer 112B can adversely affect the characteristics of the light-emitting device, this method is suitable when etching is performed using oxygen gas, such as plasma ashing.

[0340] Next, using sacrificial layers 119a, 119b, and 119c as a mask, the sacrificial film 118f in the region not covered by any of the sacrificial layers 119a, 119b, and 119c is removed by etching to form sacrificial layers 118a, 118b, and 118c.

[0341] The etching of sacrificial film 118f is described in the same way as the etching of sacrificial film 128f, so a detailed explanation is omitted.

[0342] [Formation of the first functional layer 115a to 115c and the second functional layer 116a to 116c] Next, sacrificial layers 119a, 119b, and 119c are removed by etching, and the functional films 116f and 115f in the regions not covered by sacrificial layers 118a, 118b, and 118c are removed by etching to form the second functional layer 116a, the second functional layer 116b, the second functional layer 116c, the first functional layer 115a, the first functional layer 115b, and the first functional layer 115c (Figure 20D).

[0343] By etching the functional film 116f and the functional film 115f with the sacrificial layers 119a, 119b, and 119c in the same process, the process can be simplified, increasing the productivity of the display device and reducing manufacturing costs.

[0344] In particular, it is preferable to use dry etching with an etching gas that does not contain oxygen as its main component for etching the functional films 116f and 115f. This suppresses deterioration of the functional films 156f and 155f, enabling the realization of a highly reliable display device.

[0345] The etching of functional films 116f and 115f may be performed separately from the etching of sacrificial layers 119a, 119b, and 119c. For example, functional films 116f and 115f may be etched first, and then sacrificial layers 119a, 119b, and 119c may be etched.

[0346] [Formation of insulating film 182af and insulating layer 182b] Next, the sacrificial layer 118a, sacrificial layer 118b, sacrificial layer 118c, sacrificial layer 128, sacrificial layer 128p, and the substrate 101 are covered to form the insulating film 182af.

[0347] The insulating film 182af functions as a barrier layer that prevents impurities from diffusing into the EL layer and the light-receiving layer. Examples of impurities include water. Forming the insulating film 182af by the ALD method, which has excellent step coverage, is preferable because it can suitably cover the sides of the EL layer and the light-receiving layer.

[0348] It is preferable to use the same film for the insulating film 182af as for the sacrificial layer 118, as this allows for subsequent etching in the same process. For example, it is preferable to use inorganic insulating materials such as aluminum oxide, hafnium oxide, or silicon oxide formed by the ALD method for both the insulating film 182af and the sacrificial layer 118.

[0349] Furthermore, the materials that can be used for the insulating film 182af are not limited to those listed above, and any materials that can be used for the sacrificial layer 128 can be used as appropriate.

[0350] Next, an insulating layer 182b is formed between two adjacent light-emitting devices and between adjacent light-emitting devices and a light-receiving device (Figure 20E). Figure 20E shows an example where the insulating layer 182b is formed to be wider than the width between the devices.

[0351] It is preferable to use a photosensitive resin as the insulating layer 182b. In this case, the insulating layer 182b can be formed by first forming a resin film, then exposing the resin film through a photomask, and then performing a development process. After that, the upper part of the insulating layer 182b may be removed by ashing or the like to adjust the height of the upper surface of the insulating layer 182b (Figure 21A).

[0352] When a non-photosensitive resin is used as the insulating layer 182b, the insulating layer 182b can be formed by removing the upper part of the resin film after the resin film has been deposited, until the surface of the sacrificial layer 118 and sacrificial layer 128 is exposed by ashing until the thickness is optimal.

[0353] [Etching of insulating film 182af, sacrificial layer 118, and sacrificial layer 128] Next, the insulating film 182af, sacrificial layer 118a, sacrificial layer 118b, sacrificial layer 118c, sacrificial layer 128, and sacrificial layer 128p in the area not covered by the insulating layer 182b are removed by etching, exposing the upper surface of the second functional layer 116, the upper surface of the fourth functional layer 156, and the upper surface of the electrode 111p. In addition, the insulating layer 182a is formed in the area covered by the insulating layer 182b (Figure 21B). At this time, the upper part of the insulating layer 182b may be removed, and the height of the upper surface of the insulating layer 182b may become lower.

[0354] It is preferable to perform the etching of the insulating film 182af and the sacrificial layers 118a, 118b, 118c, 128, and 128p in the same process. In particular, wet etching, which causes minimal etching damage to the second functional layer 116a, second functional layer 116b, second functional layer 116c, and fourth functional layer 156, is preferably used for etching the sacrificial layers 118a, 118b, 118c, 128, and 128p. For example, it is preferable to use wet etching with an aqueous solution of tetramethylammonium hydroxide (TMAH), dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or a mixture thereof.

[0355] Alternatively, it is preferable to remove either or both of the insulating film 182af and the sacrificial layer 118 by dissolving them in a solvent such as water or alcohol. Here, various alcohols can be used as the alcohol that can dissolve the insulating film 182af and the sacrificial layer 118, such as ethyl alcohol, methyl alcohol, isopropyl alcohol (IPA), or glycerin.

[0356] Since the sacrificial layers 118a to 118c and the sacrificial layers 128 and 128p are removed in the same process, it is preferable that the etching time required for their removal be approximately the same. For example, it is preferable to use the same material for the sacrificial layers 118a to 118c and the sacrificial layers 128 and 128p. Furthermore, it is preferable that the film thickness of the sacrificial layers 118a to 118c and the sacrificial layers 128 and 128p be approximately the same.

[0357] After removing sacrificial layers 118a, 118b, 118c, 128, and 128p, it is preferable to perform a drying treatment to remove water contained inside the light-emitting layer 112, active layer 157, first functional layer 115, second functional layer 116, third functional layer 155, fourth functional layer 156, and electrode 111p, as well as water adsorbed on the surface. For example, it is preferable to perform a heat treatment under an inert gas atmosphere or a reduced pressure atmosphere. The heat treatment can be performed at a substrate temperature of 50°C to 200°C, preferably 60°C to 150°C, and more preferably 70°C to 120°C. A reduced pressure atmosphere is preferable because it allows drying at a lower temperature.

[0358] [Formation of common electrode 123] Next, the second functional layer 116a, the second functional layer 116b, the second functional layer 116c, the fourth functional layer 156, and the electrode 111p are covered to form a common electrode 123 (Figure 21C). The common electrode 123 is electrically connected to the electrode 111p at the connection portion 140.

[0359] The common electrode 123 can be formed using a vapor deposition method or a sputtering method. Alternatively, the common electrode 123 may be formed by laminating a film formed by vapor deposition with a film formed by sputtering. It is preferable to form the common electrode 123 using a shielding mask. It is preferable to provide the shielding mask so that the common electrode 123 is not exposed at the edge of the display device 100, that is, so that the edge of the common electrode 123 is inside the edge of the display device 100.

[0360] Furthermore, a shielding mask does not need to be used when forming the common electrode 123. As shown in Figure 21D, a conductive layer 123f, which will become the common electrode 123, is formed. Subsequently, a resist mask 135 is formed on the conductive layer 123f, and the conductive layer 123f is processed to form the common electrode 123. At this time, it is preferable to process the common electrode 123 so that it is not exposed at the edge of the display device, that is, so that the edge of the common electrode 123 is inside the edge of the display device.

[0361] [Formation of protective layer 125] Next, a protective layer 125 is formed on the common electrode 123. For forming the inorganic insulating film used in the protective layer 125, sputtering, PECVD, or ALD methods are preferred. The ALD method is particularly preferred because it offers excellent step coverage and is less prone to defects such as pinholes. Furthermore, for forming the organic insulating film, the inkjet method is preferred because it allows for the formation of a uniform film in the desired region.

[0362] Based on the above, the display device shown in Figure 6A can be manufactured.

[0363] In one embodiment of the present invention, the light-emitting layer of the light-emitting device is formed using FMM, while the active layer of the light-receiving device is formed without using FMM. This configuration makes it possible to create a display device with a highly accurate light detection function.

[0364] <Example of manufacturing method 2> The method for manufacturing the display device shown in Figure 11A will be explained. Figures 22A and 22B are schematic cross-sectional views of each step in the method for manufacturing the display device. Note that the explanation will be omitted for parts that overlap with the previously described manufacturing method example 1, and the differences will be explained.

[0365] First, the insulating layer 182b is formed, similar to the method example 1 (Figure 20E).

[0366] [Etching of insulating film 182af, sacrificial layer 118, and sacrificial layer 128] Next, the insulating film 182af, sacrificial layer 118a, sacrificial layer 118b, sacrificial layer 118c, sacrificial layer 128, and sacrificial layer 128p in the area not covered by the insulating layer 182b are removed by etching, exposing the upper surface of the second functional layer 116, the upper surface of the fourth functional layer 156, and the upper surface of the electrode 111p. In addition, the insulating layer 182a is formed in the area covered by the insulating layer 182b (Figure 22A).

[0367] At this time, a sacrificial layer 118a may remain between the insulating layer 182a and the second functional layer 116a. Similarly, a sacrificial layer 118b may remain between the insulating layer 182a and the second functional layer 116b. A sacrificial layer 118c may remain between the insulating layer 182a and the second functional layer 116c. A sacrificial layer 128 may remain between the insulating layer 182a and the fourth functional layer 156. Detailed explanations of the etching of the insulating film 182af, sacrificial layer 118, and sacrificial layer 128 are omitted as they can be found in the above description.

[0368] After removing sacrificial layers 118a, 118b, 118c, 128, and 128p, it is preferable to perform a drying treatment to remove water contained inside the light-emitting layer 112, active layer 157, first functional layer 115, second functional layer 116, third functional layer 155, fourth functional layer 156, and electrode 111p, as well as water adsorbed on the surface. A detailed explanation of the drying treatment can be found in the above description, so it is omitted here.

[0369] [Formation of common electrode 123] Next, the common electrode 123 is formed by covering the insulating layer 182a, insulating layer 182b, the second functional layer 116, the fourth functional layer 156, and the electrode 111p (Figure 22B). Since the formation of the common electrode 123 can be found in the previously mentioned description, a detailed explanation is omitted.

[0370] [Formation of protective layer 125] Next, a protective layer 125 is formed on the common electrode 123. Since the formation of the protective layer 125 can be found in the previously mentioned description, a detailed explanation is omitted.

[0371] Based on the above, the display device shown in Figure 11A can be manufactured.

[0372] <Example of manufacturing method 3> The method for manufacturing the display device shown in Figure 16A will be explained. Figures 23A to 25E are schematic cross-sectional views of each step in the method for manufacturing the display device. Note that the explanation will be omitted for parts that overlap with the previously described manufacturing method example 1, and the differences will be explained.

[0373] First, electrodes 111a, 111b, 111c, 111d, and 111p are formed on the substrate 101, similar to the example of fabrication method 1 (Figure 18A).

[0374] [Formation of functional membrane 155f, active membrane 157f, and functional membrane 156f] Next, a functional film 155f, which will later become the third functional layer 155, an active film 157f, which will become the active layer 157, and a functional film 156f, which will become the fourth functional layer 156, are deposited on electrodes 111a, 111b, 111c, 111d, 111p, and the substrate 101 in that order. The formation of functional film 155f, active film 157f, and functional film 156f can be found in the previously mentioned description, so a detailed explanation is omitted.

[0375] [Formation of sacrificial film 128f and sacrificial film 129f] Next, a sacrificial film 128f and a sacrificial film 129f are formed on the functional film 156f in that order (Figure 23A).

[0376] The thickness of the sacrificial film 128f is preferably 10 nm to 3 μm, more preferably 10 nm to 2 μm, more preferably 10 nm to 1 μm, more preferably 20 nm to 1 μm, more preferably 20 nm to 500 nm, more preferably 30 nm to 500 nm, more preferably 30 nm to 400 nm, more preferably 40 nm to 400 nm, more preferably 40 nm to 300 nm, more preferably 50 nm to 300 nm, more preferably 50 nm to 200 nm, and more preferably 50 nm to 100 nm. Furthermore, the thickness of the sacrificial film 128f is preferably thicker than the thickness of the first functional layer 115.

[0377] Regarding the sacrificial film 129f, please refer to the previously mentioned description, and a detailed explanation will be omitted.

[0378] [Formation of Sacrificial Layer 129 and Sacrificial Layer 128] Next, a resist mask 133 and a resist mask 133p are formed on the sacrificial film 129f in the region overlapping with electrode 111d, and on the sacrificial film 129f in the region overlapping with connection portion 140 (Figure 23B).

[0379] Next, the sacrificial film 129f in the region not covered by either the resist mask 133 or the resist mask 133p is removed by etching to form the sacrificial layer 129 and the sacrificial layer 129p.

[0380] Next, remove the resist mask 133 (Figure 23C).

[0381] Next, using sacrificial layers 129 and 129p as a mask, the sacrificial film 128f in the region not covered by either sacrificial layer 129 or 129p is removed by etching, forming a sacrificial layer 128 in the region overlapping with electrode 111d, and forming a sacrificial layer 128p in contact with the upper surface of electrode 111p.

[0382] [Formation of the third functional layer 155, the active layer 157, and the fourth functional layer 156] Next, the sacrificial layer 129 and sacrificial layer 129p are removed by etching, and the functional film 156f, active film 157f, and functional film 155f in the regions not covered by either the sacrificial layer 128 or sacrificial layer 128p are removed by etching to form the fourth functional layer 156, the active layer 157, and the third functional layer 155 (Figure 23D).

[0383] By etching the functional film 156f, the active film 157f, and the functional film 155f, along with the sacrificial layer 129 and the sacrificial layer 129p, in the same process, the process can be simplified, increasing the productivity of the display device and reducing manufacturing costs.

[0384] In particular, detailed explanations regarding the etching of functional film 156f, active film 157f, and functional film 155f are omitted as they can be found in the previously mentioned description.

[0385] [Formation of the first functional layer 115] Next, the substrate 101, electrodes 111a, 111b, 111c, 111p, third functional layer 155, active layer 157, fourth functional layer 156, sacrificial layer 128, and sacrificial layer 128p are covered to form the first functional layer 115, first functional layer 115d, and first functional layer 115p.

[0386] Here, a region is formed between the region where the sacrificial layer 128 or sacrificial layer 128p is provided and the region where neither the sacrificial layer 128 nor the sacrificial layer 128p is provided, in which case the first functional layer is not deposited. In other words, the first functional layer is provided separately in the region where the sacrificial layer 128 or sacrificial layer 128p is provided and the region where neither the sacrificial layer 128 nor the sacrificial layer 128p is provided. Figure 24A shows the first functional layer provided separately: the first functional layer 115d deposited on the sacrificial layer 128, the first functional layer 115p deposited on the sacrificial layer 128p, and the first functional layer 115 deposited in the region where neither the sacrificial layer 128 nor the sacrificial layer 128p is provided. The first functional layer 115 is provided in contact with the upper surfaces of electrodes 111a, 111b, and 111c.

[0387] The thickness of the sacrificial film 128f, which will become the sacrificial layer 128 or sacrificial layer 128p, is preferably within the range described above. If the thickness of the sacrificial film 128f is too thin, it may become impossible to separate and provide the first functional layer 115, the first functional layer 115d, and the first functional layer 115p. Conversely, if the thickness of the sacrificial film 128f is too thick, it may become difficult to process the sacrificial film 128f. By setting the thickness of the sacrificial film 128f within the range described above, it is possible to separate and provide the first functional layer 115, the first functional layer 115d, and the first functional layer 115p, and to facilitate the processing of the sacrificial film 128f.

[0388] [Formation of light-emitting layer 112R, light-emitting layer 112G, and light-emitting layer 112B] Next, an island-shaped light-emitting layer 112R is formed on the first functional layer 115 in the region overlapping with the electrode 111a (Figure 24B). It is preferable to use FMM191R for forming the light-emitting layer 112R.

[0389] Next, using FMM191G, a light-emitting layer 112G is formed on the first functional layer 115 in the region overlapping with electrode 111b (Figure 24C).

[0390] Next, using FMM191B, a light-emitting layer 112B is formed on the first functional layer 115 in the region overlapping with the electrode 111c (Figure 24D).

[0391] The formation of the light-emitting layers 112R, 112G, and 112B can be found in the previously mentioned description, so a detailed explanation will be omitted.

[0392] The formation order of the light-emitting layer 112R, light-emitting layer 112G, and light-emitting layer 112B is not particularly limited.

[0393] [Formation of the second functional layer 116] Next, the second functional layer 116, the second functional layer 116d, and the second functional layer 116p are formed by covering the light-emitting layer 112R, light-emitting layer 112G, light-emitting layer 112B, the first functional layer 115, the first functional layer 115d, and the first functional layer 115p.

[0394] Here, a region is formed between the region where the sacrificial layer 128 or sacrificial layer 128p is provided and the region where neither the sacrificial layer 128 nor the sacrificial layer 128p is provided, in which case the second functional layer is not deposited. In other words, the second functional layer is provided separately (also called stepped) in the region where the sacrificial layer 128 or sacrificial layer 128p is provided and the region where neither the sacrificial layer 128 nor the sacrificial layer 128p is provided. Figure 25A shows the second functional layer provided separately: the second functional layer 116d deposited on the sacrificial layer 128, the second functional layer 116p deposited on the sacrificial layer 128p, and the second functional layer 116 deposited in the region where neither the sacrificial layer 128 nor the sacrificial layer 128p is provided. The second functional layer 116d is provided in contact with the first functional layer 115d. The second functional layer 116p is provided in contact with the first functional layer 115p. The second functional layer 116 is provided in contact with the first functional layer 115. In this case, the end of the second functional layer 116 may be located inward from the end of the first functional layer 115.

[0395] The thickness of the sacrificial film 128f, which will become the sacrificial layer 128 or sacrificial layer 128p, is preferably within the range described above. If the thickness of the sacrificial film 128f is too thin, it may become impossible to provide the second functional layer 116, the second functional layer 116d, and the second functional layer 116p separately. By setting the thickness of the sacrificial film 128f within the range described above, the second functional layer 116, the second functional layer 116d, and the second functional layer 116p can be provided separately.

[0396] [Removal of Sacrifice Layer 128 and Sacrifice Layer 128p] Next, the sacrificial layer 128 and the sacrificial layer 128p are removed. At this time, the first functional layer 115d and the second functional layer 116d on the sacrificial layer 128, and the first functional layer 115p and the second functional layer 116p on the sacrificial layer 128p are also removed, exposing the upper surface of the fourth functional layer 156 and the upper surface of the electrode 111p (Figure 25B).

[0397] When removing the sacrificial layer 128 and sacrificial layer 128p, it is preferable to use a method that causes as little damage as possible to the first functional layer 115, the second functional layer 116, the third functional layer 155, the active layer 157, the fourth functional layer 156, and the electrode 111p. Wet etching is preferably used to remove the sacrificial layer 128 and sacrificial layer 128p. By dissolving the sacrificial layer 128, the first functional layer 115d and the second functional layer 116d on the sacrificial layer 128 are removed together (also called lift-off). Similarly, by dissolving the sacrificial layer 128p, the first functional layer 115p and the second functional layer 116p on the sacrificial layer 128p are removed together (lift-off). By using lift-off, the first functional layer 115d, the second functional layer 116d, the first functional layer 115p, and the second functional layer 116p can be removed without damaging the first functional layer 115 and the second functional layer 116.

[0398] After removing the sacrificial layer 128 and the sacrificial layer 128p, it is preferable to perform a drying treatment to remove water contained inside the light-emitting layer 112, the active layer 157, the first functional layer 115, the second functional layer 116, the third functional layer 155, the fourth functional layer 156, and the electrode 111p, as well as water adsorbed on the surface.

[0399] [Formation of insulating film 182af and insulating layer 182b] Next, the insulating film 182af is formed by covering the second functional layer 116, the fourth functional layer 156, the electrode 111p, and the substrate 101. Since the formation of the insulating film 182af can be found in the previously mentioned description, a detailed explanation is omitted.

[0400] Next, an insulating layer 182b is formed between two adjacent light-emitting devices and between adjacent light-emitting devices and a light-receiving device (Figure 25C). A detailed explanation of the formation of the insulating layer 182b is omitted as it can be found in the previously mentioned description.

[0401] [Etching of insulating film 182af] Next, the insulating film 182af in the area not covered by the insulating layer 182b is removed by etching, exposing the upper surface of the second functional layer 116, the upper surface of the fourth functional layer 156, and the upper surface of the electrode 111p. In addition, the insulating layer 182a is formed in the area covered by the insulating layer 182b (Figure 25D). A detailed explanation of the etching of the insulating film 182af is omitted as it can be found in the previous description.

[0402] [Formation of common electrode 123] Next, the second functional layer 116, the fourth functional layer 156, and the electrode 111p are covered to form a common electrode 123 (Figure 25E). The common electrode 123 is electrically connected to the electrode 111p at the connection portion 140.

[0403] [Formation of protective layer 125] Next, a protective layer 125 is formed on the common electrode 123.

[0404] Based on the above, the display device shown in Figure 16A can be manufactured.

[0405] The above is an explanation of one example of a method for manufacturing a display device.

[0406] As described above, in the method for manufacturing a display device according to one aspect of the present invention, a light-emitting device and a light-receiving device can be manufactured separately on the same substrate. Furthermore, the light-emitting device and the light-receiving device can be configured to have no common components other than a common electrode. This makes it possible to increase the signal-to-noise ratio of the light-receiving device, resulting in a display device with a highly accurate light-receiving device. In addition, it is possible to create a display device with low power consumption.

[0407] <Pixel layout> This section explains the layout of pixels. There are no particular limitations on the arrangement of subpixels, and various methods can be applied. Examples of subpixel arrangements include stripe arrangements, S-stripe arrangements, matrix arrangements, delta arrangements, Bayer arrangements, and pentile arrangements.

[0408] The top surface shape of a sub-pixel can be, for example, a polygon such as a triangle, quadrilateral (including rectangles and squares), or pentagon, or a polygon with rounded corners, or an ellipse or a circle. Here, the top surface shape of a sub-pixel corresponds to the top surface shape of the light-emitting area of ​​a light-emitting device or the light-receiving area of ​​a light-receiving device.

[0409] The display device 100A shown in Figure 4A consists of one pixel 103 arranged in two rows and three columns. Pixel 103 has three subpixels (subpixels 120R, 120G, and 120B) in the top row (1st row) and one subpixel (subpixel 130) in the bottom row (2nd row). In other words, pixel 103 has subpixel 120R in the left column (1st column), subpixel 120G in the middle column (2nd column), subpixel 120B in the right column (3rd column), and subpixel 130 extending across these three columns.

[0410] In this embodiment, to clearly explain the pixel layout, the horizontal direction (X direction) of the drawing is referred to as the row direction and the vertical direction (Y direction) as the column direction. However, the invention is not limited to this, and the row and column directions can be swapped. Therefore, in this specification, one of the row and column directions may be referred to as the first direction, and the other as the second direction. The second direction is perpendicular to the first direction. Note that if the top surface shape of the display unit is rectangular, the first and second directions do not necessarily have to be parallel to the straight lines of the outline of the display unit. Furthermore, the top surface shape of the display unit is not limited to a rectangle; it may be a polygon or a curved shape (circle, ellipse, etc.), and the first and second directions can be any direction relative to the display unit.

[0411] In this embodiment, the order of subpixels is shown from left to right in the drawing for clarity, but it is not limited to this order and can be rearranged to start from right. Similarly, the order of subpixels is shown from top to bottom in the drawing, but it is not limited to this order and can be rearranged to start from bottom.

[0412] Figures 26A and 26B show pixel arrangements different from those in Figure 4A.

[0413] The display device 100B shown in Figure 26A has a stripe arrangement applied to the pixels 103. Each pixel 103 has sub-pixels 120R, 120G, 120B, and 130 in the row direction.

[0414] The display device 100C shown in Figure 26B has a matrix array applied to the pixels 103. Each pixel 103 is composed of two rows and two columns, with two subpixels (subpixels 120R and 120G) in the top row (row 1) and two subpixels (subpixels 120B and 130) in the bottom row (row 2). In other words, each pixel 103 has two subpixels (subpixels 120R and 130) in the left column (row 1) and two subpixels (subpixels 120G and 120B) in the right column (row 2).

[0415] The positions of each subpixel are not particularly limited. For example, the positions of subpixel 120R and subpixel 130 may be swapped.

[0416] The area of ​​the light-emitting region of each subpixel's light-emitting device may be the same or different. For example, the area of ​​the light-emitting region can be determined according to the lifespan of the light-emitting device. It is preferable to make the area of ​​the light-emitting region of a light-emitting device with a short lifespan larger than the area of ​​the light-emitting regions of other light-emitting devices. By increasing the area of ​​the light-emitting region, the current density applied to the light-emitting device decreases, thus extending the lifespan of the light-emitting device. In other words, a highly reliable display device can be created.

[0417] The configuration examples illustrated in this embodiment, and the corresponding drawings, etc., can be appropriately combined with other configuration examples or drawings, etc., at least in part.

[0418] This embodiment can be implemented in appropriate combination with other embodiments described herein, at least in part.

[0419] (Embodiment 2) In this embodiment, a display device according to one aspect of the present invention will be described with reference to Figures 27 to 36.

[0420] The display device of this embodiment can be a high-definition display device. Therefore, the display device of this embodiment can be used, for example, as a display unit for information terminals (wearable devices) such as wristwatches and bracelets, and as a display unit for wearable devices that can be worn on the head, such as VR devices such as head-mounted displays and AR devices such as glasses.

[0421] 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 equipment, 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.

[0422] <Display Module> Figure 27A shows a perspective view of the display module 280. The display module 280 includes a display device 100A and an FPC 290. Note that the display device included in the display module 280 is not limited to display device 100A, but may be any of the display devices 100B to 100F described later.

[0423] 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.

[0424] Figure 27B 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 composed of multiple wires.

[0425] The pixel section 284 has multiple pixels 284a arranged in a matrix. A magnified view of one pixel 284a is shown on the right side of Figure 27B. The pixel 284a has a light-emitting device 110R that emits red light, a light-emitting device 110G that emits green light, a light-emitting device 110B that emits blue light, and a light-receiving device 150.

[0426] The pixel circuit section 283 has a plurality of pixel circuits 283a arranged in a matrix.

[0427] A single pixel circuit 283a is a circuit that controls the driving of multiple elements in a single pixel 284a. A single pixel circuit 283a may be configured to have five circuits for controlling the driving of elements. For example, a pixel circuit 283a can be configured to have at least one selection transistor, one current control transistor (driving transistor), and a capacitor 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 the source. This realizes an active-matrix type display device.

[0428] 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.

[0429] 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.

[0430] The display module 280 can be configured such that one or both of the pixel circuit section 283 and the circuit section 282 are stacked on the lower side of the pixel section 284, 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.

[0431] 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.

[0432] <Display device 100A> The display device 100A shown in Figure 28 includes a substrate 301, a light-emitting device 110R, a light-emitting device 110G, a light-receiving device 150, a capacitor 240, and a transistor 310.

[0433] Substrate 301 corresponds to substrate 291 in Figures 27A and 27B. The laminated structure from substrate 301 to insulating layer 255b corresponds to substrate 101 in Embodiment 1.

[0434] 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 has 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 a source or drain. The insulating layer 314 is provided covering the side surface of the conductive layer 311.

[0435] An element isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301.

[0436] An insulating layer 261 is provided covering the transistor 310, and a capacitance 240 is provided on the insulating layer 261.

[0437] The capacitor 240 has a conductive layer 241, a conductive layer 245, and an insulating layer 243 located between them. The conductive layer 241 acts as one electrode of the capacitor 240, the conductive layer 245 acts as the other electrode of the capacitor 240, and the insulating layer 243 acts as the dielectric of the capacitor 240.

[0438] 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 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.

[0439] An insulating layer 255a is provided covering the capacitance 240, and an insulating layer 255b is provided on top of the insulating layer 255a.

[0440] The insulating layer 255a and the insulating layer 255b can preferably use various inorganic insulating films such as oxide insulating films, nitride insulating films, oxidative nitride insulating films, and oxidative nitride insulating films. For insulating layer 255a, it is preferable to use an oxide insulating film or oxidative nitride insulating film such as a silicon oxide film, silicon oxidative nitride film, or aluminum oxide film. For insulating layer 255b, it is preferable to use a nitride insulating film or oxidative nitride insulating film such as a silicon nitride film or silicon oxidative nitride film. More specifically, it is preferable to use a silicon oxide film as insulating layer 255a and a silicon nitride film as insulating layer 255b. It is preferable that insulating layer 255b has the function of an etching protective film. Alternatively, a nitride insulating film or oxidative nitride insulating film may be used as insulating layer 255a, and an oxide insulating film or oxidative nitride insulating film may be used as insulating layer 255b. In this embodiment, an example is shown in which a recess is provided in insulating layer 255b, but the insulating layer 255b does not necessarily have to have a recess.

[0441] Light-emitting devices 110R, 110G, and 150 are provided on the insulating layer 255b. The configurations of the light-emitting devices and 150 shown in Embodiment 1 can be applied to each of the light-emitting devices 110R, 110G, and 150. An insulator is provided between adjacent light-emitting devices and between adjacent light-emitting devices and 150. Figure 28 shows a configuration in which an insulating layer 182a and an insulating layer 182b on the insulating layer 182a are provided in this region.

[0442] The electrodes 111a, 111b, and 111d of the light-emitting device are electrically connected to the source or drain of the transistor 310 by plugs 256 embedded in insulating layers 255a and 255b, a conductive layer 241 embedded in insulating layer 254, and a plug 271 embedded in insulating layer 261. The height of the top surface of insulating layer 255b and the height of the top surface of plug 256 are equal or approximately equal. Various conductive materials can be used for the plugs.

[0443] A protective layer 131 is provided on the light-emitting device 110R, the light-emitting device 110G, and the light-receiving device 150. A substrate 120 is bonded to the protective layer 131 by a resin layer 122. Details of the components from the light-emitting device to the substrate 120 can be found in Embodiment 1. The substrate 120 corresponds to the substrate 292 in Figure 27A.

[0444] The upper edges of electrodes 111a, 111b, and 111d are not covered by an insulating layer. Therefore, the spacing between adjacent light-emitting devices can be made extremely narrow. Consequently, a high-definition or high-resolution display device can be achieved.

[0445] Figure 4B and others show examples in which the light-emitting device 110R, light-emitting device 110G, and light-emitting device 110B each have different configurations of EL layers 175R, EL layer 175G, and EL layer 175B. However, EL layers 175R, EL layer 175G, and EL layer 175B may have the same configuration.

[0446] For example, the light-emitting devices 110R, 110G, and 110B can all be configured to emit white light. Furthermore, a colored layer may be provided in the region overlapping with the light-emitting device 110. By providing a colored layer that transmits red light in the region overlapping with the light-emitting device 110R, the light emitted from the light-emitting device 110R is extracted as red light to the outside of the display device via the colored layer. Similarly, by providing a colored layer that transmits green light in the region overlapping with the light-emitting device 110G, the light emitted from the light-emitting device 110G is extracted as green light to the outside of the display device via the colored layer. By providing a colored layer that transmits blue light in the region overlapping with the light-emitting device 110B, the light emitted from the light-emitting device 110B is extracted as blue light to the outside of the display device via the colored layer.

[0447] <Display device 100B> The display device 100B shown in Figure 29 has a configuration in which transistors 310A and 310B, each with a channel formed on a semiconductor substrate, are stacked. In the following description of the display device, parts that are the same as those described earlier may be omitted.

[0448] The display device 100B has a configuration in which a substrate 301B on which a transistor 310B, a capacitor 240, and a light-emitting device are provided, and a substrate 301A on which a transistor 310A is provided are bonded together.

[0449] Here, it is preferable to provide an insulating layer 345 on the lower surface of substrate 301B. It is also preferable to provide an insulating layer 346 on top of the insulating layer 261 provided on substrate 301A. Insulating layers 345 and 346 are insulating layers that function as protective layers and can suppress the diffusion of impurities into substrates 301B and 301A. Insulating layers 345 and 346 can be made of inorganic insulating films that can be used for protective layer 131 or insulating layer 332.

[0450] A plug 343 is provided on the substrate 301B, penetrating both the substrate 301B and the insulating layer 345. It is preferable to provide an insulating layer 344 covering the sides of the plug 343. The insulating layer 344 functions as a protective layer and can suppress the diffusion of impurities into the substrate 301B. The insulating layer 344 can be made of an inorganic insulating film that can be used for the protective layer 131.

[0451] A conductive layer 342 is provided on the back side of the substrate 301B (the side opposite to the substrate 120 side), beneath the insulating layer 345. Preferably, the conductive layer 342 is provided so as to be embedded in the insulating layer 335. Also, preferably, the undersides of the conductive layer 342 and the insulating layer 335 are flattened. Here, the conductive layer 342 is electrically connected to the plug 343.

[0452] On the other hand, the substrate 301A has a conductive layer 341 provided on an insulating layer 346. Preferably, the conductive layer 341 is provided so as to be embedded in the insulating layer 336. Furthermore, it is preferable that the upper surfaces of the conductive layer 341 and the insulating layer 336 are flattened.

[0453] The conductive layer 341 and the conductive layer 342 are bonded together, thereby electrically connecting the substrate 301A and the substrate 301B. By improving the flatness of the surface formed by the conductive layer 342 and the insulating layer 335, and the surface formed by the conductive layer 341 and the insulating layer 336, the bonding of the conductive layer 341 and the conductive layer 342 can be improved.

[0454] It is preferable that conductive layers 341 and 342 use the same conductive material. For example, a metal film containing an element selected from Al, Cr, Cu, Ta, Ti, Mo, and W, or a metal nitride film (titanium nitride film, molybdenum nitride film, tungsten nitride film) composed of the above elements can be used. In particular, it is preferable to use copper for conductive layers 341 and 342. This allows the application of Cu-Cu (copper-copper) direct bonding technology (a technology that achieves electrical conductivity by connecting Cu (copper) pads to each other).

[0455] <Display device 100C> The display device 100C shown in Figure 30 has a configuration in which conductive layer 341 and conductive layer 342 are joined via bumps 347.

[0456] As shown in Figure 30, the conductive layer 341 and the conductive layer 342 can be electrically connected by providing a bump 347 between them. The bump 347 can be formed using a conductive material containing, for example, gold (Au), nickel (Ni), indium (In), or tin (Sn). Solder may also be used as the bump 347. An adhesive layer 348 may also be provided between the insulating layer 345 and the insulating layer 346. Furthermore, when the bump 347 is provided, the insulating layer 335 and the insulating layer 336 may be omitted.

[0457] <Display device 100D> The display device 100D shown in Figure 31 differs from the display device 100A mainly in its transistor configuration.

[0458] Transistor 320 is a transistor (hereinafter referred to as an OS transistor) in which a metal oxide (also called an oxide semiconductor) is applied to the semiconductor layer where the channel is formed.

[0459] The transistor 320 has 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.

[0460] Substrate 331 corresponds to substrate 291 in Figures 27A and 27B. The laminated structure from substrate 331 to insulating layer 255b corresponds to substrate 101 in Embodiment 1. Substrate 331 can be an insulating substrate or a semiconductor substrate.

[0461] 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. The insulating layer 332 can be made of a film that is less permeable to hydrogen or oxygen than a silicon oxide film, such as an aluminum oxide film, a hafnium oxide film, or a silicon nitride film.

[0462] 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.

[0463] The semiconductor layer 321 is provided on the insulating layer 326. Preferably, the semiconductor layer 321 has a metal oxide (oxide semiconductor) film having semiconductor properties. A pair of conductive layers 325 are provided in contact with the semiconductor layer 321 and function as source electrodes and drain electrodes.

[0464] An insulating layer 328 is provided covering the top and side surfaces of a pair of conductive layers 325, as well as the side surfaces of the semiconductor layer 321, and an insulating layer 264 is provided on top of 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. The insulating layer 328 can be made of the same insulating film as the insulating layer 332.

[0465] 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.

[0466] The upper surfaces of the conductive layer 324, the insulating layer 323, and the insulating layer 264 are flattened so that their heights are the same or approximately the same, and the insulating layer 329 and insulating layer 265 are provided covering them.

[0467] 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. Insulating layer 329 can be an insulating film similar to that used for insulating layers 328 and 332.

[0468] 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, 264, and 328. Here, it is preferable that the plug 274 has a conductive layer 274a that covers the sides of the openings of each 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.

[0469] <Display device 100E> The display device 100E shown in Figure 32 has a configuration in which transistors 320A and 320B, each having an oxide semiconductor in the semiconductor where the channel is formed, are stacked.

[0470] The configuration of transistors 320A, 320B, and their surrounding components can be based on the display device 100D described above.

[0471] In this example, we have used a configuration in which two transistors having oxide semiconductors are stacked, but this is not the only option. For example, a configuration in which three or more transistors are stacked may also be used.

[0472] <Display device 100F> The display device 100F shown in Figure 33 has a configuration in which a transistor 310 with a channel formed on a substrate 301 and a transistor 320 containing a metal oxide on the semiconductor layer in which the channel is formed are stacked.

[0473] 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.

[0474] 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.

[0475] 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.

[0476] <Display device 100G> Figure 34 shows a perspective view of the display device 100G, and Figure 35A shows a cross-sectional view of the display device 100G.

[0477] The display device 100G has a configuration in which substrate 152 and substrate 151 are bonded together. In Figure 34, substrate 152 is clearly indicated by a dashed line.

[0478] The display device 100G includes a display unit 162, a connection unit 140, a circuit 164, wiring 165, etc. Figure 34 shows an example in which IC 173 and FPC 172 are mounted on the display device 100G. Therefore, the configuration shown in Figure 34 can also be described as a display module having the display device 100G, an IC (integrated circuit), and an FPC.

[0479] The connection portion 140 is provided on the outside of the display portion 162. The connection portion 140 can be provided along one or more sides of the display portion 162. There may be one or more connection portions 140. Figure 34 shows an example in which the connection portion 140 is provided so as to surround all four sides of the display portion. At the connection portion 140, the common electrode of the light-emitting device and the conductive layer are electrically connected, and a potential can be supplied to the common electrode.

[0480] Circuit 164 can, for example, be a scan line drive circuit.

[0481] 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.

[0482] Figure 34 shows an example in which IC 173 is provided 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 100G 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.

[0483] Figure 35A shows an example of a cross-section of the display device 100G when a portion of the area including the FPC 172, a portion of the circuit 164, a portion of the display unit 162, a portion of the connection unit 140, and a portion of the area including the end are cut.

[0484] The display device 100G shown in Figure 35A has transistors 201, 205, light-emitting device 110R, light-emitting device 110G, and light-receiving device 150, etc., between substrates 151 and 152.

[0485] The light-emitting device 110R, the light-emitting device 110G, and the light-receiving device 150 can be configured in accordance with Embodiment 1, except that the pixel electrode configuration differs.

[0486] The light-emitting device 110R has a conductive layer 113a, a conductive layer 126a on the conductive layer 113a, and a conductive layer 127a on the conductive layer 126a. All of the conductive layers 113a, 126a, and 127a can be called pixel electrodes, or only a part of them can be called pixel electrodes.

[0487] The light-emitting device 110G includes a conductive layer 113b, a conductive layer 126b on the conductive layer 113b, and a conductive layer 127b on the conductive layer 126b.

[0488] The light-receiving device 150 has a conductive layer 113d, a conductive layer 126d on the conductive layer 113d, and a conductive layer 127d on the conductive layer 126d.

[0489] The conductive layer 113a is connected to the conductive layer 222b of the transistor 205 through an opening provided in the insulating layer 214. The edge of the conductive layer 126a is located outside the edge of the conductive layer 113a. The edges of the conductive layer 126a and the conductive layer 127a are aligned or approximately aligned. For example, conductive layers that function as reflective electrodes can be used for conductive layers 113a and 126a, and a conductive layer that functions as a transparent electrode can be used for conductive layer 127a.

[0490] Detailed explanations of conductive layers 113b, 126b, and 127b in the light-emitting device 110G, and conductive layers 113d, 126d, and 127d in the light-receiving device 150 can be found by referring to the descriptions of conductive layer 113a, conductive layer 126a, and conductive layer 127a, respectively, so a detailed explanation is omitted.

[0491] The conductive layers 113a, 113b, and 113d have recesses formed to cover the openings provided in the insulating layer 214. Layer 184 is embedded in these recesses.

[0492] Layer 184 has the function of flattening the recesses of conductive layers 113a, 113b, and 113d. Conductive layers 126a, 126b, and 126d, which are electrically connected to conductive layers 113a, 113b, and 113d, are provided on conductive layers 113a, 113b, and 113d and on layer 184. Therefore, regions overlapping with the recesses of conductive layers 113a, 113b, and 113d can also be used as light-emitting regions, thereby increasing the aperture ratio of the pixels.

[0493] Layer 184 may be an insulating layer or a conductive layer. Various inorganic insulating materials, organic insulating materials, and conductive materials can be used for layer 184 as appropriate. In particular, it is preferable that layer 184 be formed using an insulating material.

[0494] Layer 184 can suitably be an insulating layer having an organic material. For example, acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimidoamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins can be used as layer 184. Alternatively, a photosensitive resin can be used as layer 184. The photosensitive resin can be a positive-type material or a negative-type material.

[0495] By using a photosensitive resin, layer 184 can be fabricated using only exposure and development processes, thereby reducing the impact of dry etching or wet etching on the surfaces of conductive layers 113a, 113b, and 113d. Furthermore, by forming layer 184 using a negative-type photosensitive resin, it may be possible to form layer 184 using the same photomask (exposure mask) as the one used to form the openings in the insulating layer 214.

[0496] Figure 35A shows an example in which the upper surface of layer 184 has a flat portion, but the present invention is not limited to this. The upper surface of layer 184 may, for example, have a shape in which the center and its vicinity are recessed in a cross-sectional view, that is, a shape having a concave curved surface. Alternatively, the upper surface of layer 184 may have a shape in which the center and its vicinity are bulging in a cross-sectional view, that is, a shape having a convex curved surface. Alternatively, the upper surface of layer 184 may have one or both a convex curved surface and a concave curved surface. The number of convex and concave curved surfaces on the upper surface of layer 184 is not limited and can be one or more.

[0497] The height of the top surface of layer 184 and the height of the top surface of the conductive layer 113 may be the same, approximately the same, or different from each other. For example, the height of the top surface of layer 184 may be lower or higher than the height of the top surface of the conductive layer 113.

[0498] The top and side surfaces of conductive layer 126a and conductive layer 127a are covered by EL layer 175R. Similarly, the top and side surfaces of conductive layer 126b and conductive layer 127b are covered by EL layer 175G. In addition, the top and side surfaces of conductive layer 126d and conductive layer 127d are covered by light-receiving layer 177. Therefore, the entire region where conductive layers 126a and 126b are provided can be used as the light-emitting region of light-emitting device 110R and light-emitting device 110G, thereby increasing the aperture ratio of the pixels. Similarly, the entire region where conductive layer 126d is provided can be used as the light-receiving region of light-receiving device 150, thereby enabling a display device with high-sensitivity light-receiving capabilities.

[0499] The sides of the EL layer 175R, EL layer 175G, and light-receiving layer 177 are covered by insulating layers 182a and 182b, respectively. A sacrificial layer 118a is located between the EL layer 175R and the insulating layer 182a. A sacrificial layer 118b is located between the EL layer 175G and the insulating layer 182a, and a sacrificial layer 128 is located between the light-receiving layer 177 and the insulating layer 182a. A common electrode 123 is provided on the EL layer 175R, EL layer 175G, light-receiving layer 177, and insulating layers 182a and 182b. The common electrode 123 is a continuous film provided in common to multiple light-emitting devices 110 and light-receiving devices 150.

[0500] A protective layer 131 is provided on each of the light-emitting devices 110R, 110G, and 150. The protective layer 131 and the substrate 152 are bonded together via an adhesive layer 142. For sealing the light-emitting devices, a solid sealing structure or a hollow sealing structure can be applied. In Figure 35A, the space between the substrate 152 and the substrate 151 is filled with the adhesive layer 142, indicating a solid sealing structure. Alternatively, the space may be filled with an inert gas (such as nitrogen or argon), indicating a hollow sealing structure. In this case, the adhesive layer 142 may be provided so as not to overlap with the light-emitting devices. Furthermore, the space may be filled with a resin different from the adhesive layer 142, which is provided in a frame shape.

[0501] In the connection portion 140, a conductive layer 186 is provided on the insulating layer 214. The conductive layer 186 is shown as an example of a laminated structure consisting of a conductive film obtained by processing the same conductive film as conductive layers 113a, 113b, and 113d, a conductive film obtained by processing the same conductive film as conductive layers 126a, 126b, and 126d, and a conductive film obtained by processing the same conductive film as conductive layers 127a, 127b, and 127d. The ends of the conductive layer 186 are covered by a sacrificial layer 128p, an insulating layer 182a, and an insulating layer 182b. A common electrode 123 is also provided on the conductive layer 186. The conductive layer 186 is electrically connected to the common electrode 123. The conductive layer 186 and the common electrode 123 may be electrically connected by direct contact, or they may be electrically connected via other conductive layers.

[0502] The display device 100G is a top-emission type. The light emitted by the light-emitting device is emitted towards the substrate 152. It is preferable to use a material with high transmittance to visible light for the substrate 152. The pixel electrodes contain a material that reflects visible light, and the counter electrodes (common electrodes 123) contain a material that transmits visible light.

[0503] The laminated structure from substrate 151 to insulating layer 214 corresponds to substrate 101 in Embodiment 1.

[0504] Both transistors 201 and 205 are formed on the substrate 151. These transistors can be manufactured using the same materials and the same process.

[0505] 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.

[0506] 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.

[0507] Insulating layers 211, 213, and 215 are preferably made of inorganic insulating films. Examples of inorganic insulating films include silicon nitride, silicon oxide nitride, silicon oxide, silicon nitride, aluminum oxide, and aluminum nitride. Alternatively, hafnium oxide, yttrium oxide, zirconium oxide, gallium oxide, tantalum oxide, magnesium oxide, lanthanum oxide, cerium oxide, and neodymium oxide may be used. Furthermore, two or more of the above insulating films may be laminated together.

[0508] An organic insulating layer is preferred for the insulating layer 214, which functions as a planarizing layer. Examples of materials that can be used for the organic insulating layer include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimidoamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins. Alternatively, the insulating layer 214 may have a laminated structure of an organic insulating layer and an inorganic insulating layer. The outermost layer of the insulating layer 214 preferably functions as an etching protection layer. This makes it possible to suppress the formation of depressions in the insulating layer 214 when processing conductive layers 113a, 126a, or 127a. Alternatively, depressions may be provided in the insulating layer 214 when processing conductive layers 113a, 126a, or 127a.

[0509] 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.

[0510] 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.

[0511] 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.

[0512] The crystallinity of the semiconductor material used in the transistor is not particularly limited; amorphous semiconductors, crystalline semiconductors (microcrystalline semiconductors, polycrystalline semiconductors, single-crystal semiconductors, or semiconductors with crystalline regions in part) may be used. Using a crystalline semiconductor is preferable because it can suppress the degradation of transistor characteristics.

[0513] The semiconductor layer of the transistor preferably has a metal oxide (oxide semiconductor). In other words, the display device of this embodiment preferably has an OS transistor.

[0514] Examples of crystalline oxide semiconductors include CAAC (c-axis-aligned crystalline)-OS and nc (nanocrystalline)-OS.

[0515] Alternatively, a transistor using silicon as the channel-forming region (Si transistor) may be used. Examples of silicon include single-crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, a transistor having low-temperature polysilicon (LTPS) in the semiconductor layer (hereinafter also referred to as an LTPS transistor) can be used. LTPS transistors have high field-effect mobility and good frequency characteristics.

[0516] By using Si transistors such as LTPS transistors, circuits that need to be driven at high frequencies (e.g., source driver circuits) can be fabricated on the same board as the display unit. This simplifies the external circuits implemented in the display device, reducing component and mounting costs.

[0517] OS transistors have extremely high field-effect mobility compared to transistors using amorphous silicon. Furthermore, OS transistors exhibit remarkably low source-drain leakage current (hereinafter also referred to as off-current) in the off state, allowing them to retain charge stored in a capacitor connected in series with the transistor for extended periods. Additionally, the application of OS transistors can reduce the power consumption of display devices.

[0518] At room temperature, the off-current value of an OS transistor per 1 μm channel width is 1 aA (1 × 10⁻¹⁶). -18 A) Below, 1zA(1×10 -21 A) Less than or equal to 1yA(1×10 -24 A) It can be less than or equal to the following. Note that the off-current value of a Si transistor per 1 μm of channel width at room temperature is 1 fA (1 × 10⁻¹⁰). -15 A) More than 1pA (1×10 -12A) The answer is as follows. Therefore, it can be said that the off-current of an OS transistor is about 10 orders of magnitude lower than that of a Si transistor.

[0519] To increase the luminescence brightness of a light-emitting device included in a pixel circuit, it is necessary to increase the amount of current flowing through the device. To achieve this, the source-drain voltage of the drive transistor included in the pixel circuit must be increased. Compared to Si transistors, OS transistors have a higher breakdown voltage between the source and drain, allowing a higher voltage to be applied to the source-drain of an OS transistor. Therefore, by using an OS transistor as the drive transistor in the pixel circuit, the amount of current flowing through the light-emitting device can be increased, thereby increasing the luminescence brightness of the device.

[0520] When a transistor operates in the saturation region, an OS transistor exhibits a smaller change in source-drain current in response to a change in gate-source voltage compared to a Si transistor. Therefore, by using an OS transistor as the driving transistor in a pixel circuit, the current flowing between the source and drain can be precisely controlled by the change in gate-source voltage, thereby controlling the amount of current flowing to the light-emitting device. This allows for a wider range of tonal gradations in the pixel circuit.

[0521] In terms of the saturation characteristics of the current flowing when a transistor operates in the saturation region, OS transistors can supply a more stable current (saturation current) than Si transistors, even when the source-drain voltage gradually increases. Therefore, by using OS transistors as driving transistors, a stable current can be supplied to the light-emitting device even if there are variations in the current-voltage characteristics of the EL device. In other words, when operating in the saturation region, the source-drain current remains almost unchanged even when the source-drain voltage is increased, thus stabilizing the luminescence brightness of the light-emitting device.

[0522] As described above, by using OS transistors in the drive transistors included in the pixel circuit, it is possible to achieve "suppression of black level floating," "increase in luminescence brightness," "multi-gradation," and "suppression of variations in light-emitting devices."

[0523] The semiconductor layer preferably comprises, for example, indium, element 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, it is preferable that M is one or more selected from aluminum, gallium, yttrium, and tin.

[0524] In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also written as IGZO) as the semiconductor layer. Alternatively, it is preferable to use an oxide containing indium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium, gallium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), and zinc (Zn) (also written as IAZO). Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), gallium (Ga), and zinc (Zn) (also written as IAGZO).

[0525] 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 greater than or equal to the atomic ratio of M. Possible atomic ratios of metal elements in such an In-M-Zn oxide include: In:M:Zn=1:1:1 or near that composition, In:M:Zn=1:1:1.2 or near that composition, In:M:Zn=1:3:2 or near that composition, In:M:Zn=1:3:4 or near that composition, In:M:Zn=2:1:3 or near that composition, In:M:Zn=3:1:2 or near that composition, and In:M:Zn=4:2:3 Examples include compositions near the desired atomic ratio, such as In:M:Zn=4:2:4.1 or near that ratio, In:M:Zn=5:1:3 or near that ratio, In:M:Zn=5:1:6 or near that ratio, In:M:Zn=5:1:7 or near that ratio, In:M:Zn=5:1:8 or near that ratio, In:M:Zn=6:1:6 or near that ratio, In:M:Zn=5:2:5 or near that ratio, etc. Note that "nearby composition" includes a range of ±30% of the desired atomic ratio.

[0526] 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 the atomic ratio of In is 4, the atomic ratio of Ga is between 1 and 3, and the atomic ratio of 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 the atomic ratio of In is 5, the atomic ratio of Ga is greater than 0.1 and 2 or less, and the atomic ratio of 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 the atomic ratio of In is 1, the atomic ratio of Ga is greater than 0.1 and 2 or less, and the atomic ratio of Zn is greater than 0.1 and 2 or less.

[0527] 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.

[0528] All of the transistors in the display unit 162 may be OS transistors, all of the transistors in the display unit 162 may be Si transistors, or some of the transistors in the display unit 162 may be OS transistors and the rest may be Si transistors.

[0529] For example, by using both LTPS transistors and OS transistors in the display unit 162, a display device with low power consumption and high driving capability can be realized. Furthermore, a configuration combining LTPS transistors and OS transistors is sometimes referred to as LTPO. As a more preferable example, it is preferable to apply OS transistors to transistors that function as switches for controlling conduction and non-conduction between wiring, and LTPS transistors to transistors that control current.

[0530] For example, one of the transistors in the display unit 162 functions as a transistor for controlling the current flowing to the light-emitting device, and can also be called a drive transistor. One of the source and drain of the drive transistor is electrically connected to the pixel electrode of the light-emitting device. It is preferable to use an LTPS transistor for this drive transistor. This makes it possible to increase the current flowing to the light-emitting device in the pixel circuit.

[0531] On the other hand, the other transistor in the display unit 162 functions as a switch for controlling the selection and deselection of pixels, and can also be called a selection transistor. The gate of the selection transistor is electrically connected to the gate line, and one of the source and drain is electrically connected to the source line (signal line). It is preferable to use an OS transistor for the selection transistor. This makes it possible to maintain the gradation of pixels even when the frame frequency is significantly reduced (e.g., 1 fps or less), and thus power consumption can be reduced by stopping the driver when displaying still images.

[0532] Thus, a display device according to one aspect of the present invention can combine a high aperture ratio, high resolution, high display quality, and low power consumption.

[0533] Figures 35B and 35C show other examples of transistor configurations.

[0534] 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.

[0535] In the transistor 209 shown in Figure 35B, 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.

[0536] On the other hand, in the transistor 210 shown in Figure 35C, 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 35C can be fabricated by processing the insulating layer 225 using the conductive layer 223 as a mask. In Figure 35C, 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.

[0537] 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 conductive layers 113a, 113b, and 113d, a conductive film obtained by processing the same conductive film as conductive layers 126a, 126b, and 126d, and a conductive film obtained by processing the same conductive film as conductive layers 127a, 127b, and 127d. On the upper surface of the connection portion 204, the conductive layer 166 is exposed. This allows the connection portion 204 and FPC 172 to be electrically connected via the connection layer 242.

[0538] It is preferable to provide a light-shielding layer 117 on the surface of the substrate 152 that faces the substrate 151. The light-shielding layer 117 can be provided between adjacent light-emitting devices, at connection points 140, and in circuits 164, etc. In addition, various optical components can be arranged on the outside of the substrate 152.

[0539] By providing a protective layer 131 that covers 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.

[0540] Substrates 151 and 152 can each be made of materials that can be used for substrate 120.

[0541] The adhesive layer 142 can be made of a material that can be used for the resin layer 122.

[0542] The connecting layer 242 can be made of an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0543] <Display device 100H> A modified example of the display device 100G is shown in Figure 36. The display device 100H differs from the display device 100G mainly in that it has a substrate 153, an adhesive layer 159, and an insulating layer 212 instead of substrate 151, and a substrate 154, an adhesive layer 160, and an insulating layer 158 instead of substrate 152.

[0544] The display device 100H has a substrate 153 and an insulating layer 212 bonded together by an adhesive layer 159. In addition, a substrate 154 and an insulating layer 158 are bonded together by an adhesive layer 160.

[0545] Figure 36 shows a configuration in which a filter 149 that cuts out ultraviolet light is provided in the area overlapping with the light receiving device 150. Note that a configuration without the filter 149 is also possible.

[0546] When manufacturing the display device 100H shown in Figure 36, first, a first manufacturing substrate on which an insulating layer 212, transistors, light-emitting device 110, and light-receiving device 150 are provided, and a second manufacturing substrate on which an insulating layer 158, light-shielding layer 117, and filter 149 are provided, are bonded together with an adhesive layer 142. Then, the first manufacturing substrate is peeled off and a substrate 153 is attached to the exposed surface using an adhesive layer 159. This transfers the components formed on the first manufacturing substrate to the substrate 153. Similarly, the second manufacturing substrate is peeled off and a substrate 154 is attached to the exposed surface using an adhesive layer 160. This transfers the components formed on the second manufacturing substrate to the substrate 154. It is preferable that both substrates 153 and 154 are flexible. This allows the display device 100H to be flexible. In other words, the display device 100H can be made into a flexible display.

[0547] Insulating layer 212 and insulating layer 158 can be made of an inorganic insulating film that can be used for insulating layer 211, insulating layer 213, and insulating layer 215, respectively.

[0548] This embodiment can be combined with other embodiments as appropriate.

[0549] (Embodiment 3) This embodiment describes a light-emitting device that can be used in a display device according to one aspect of the present invention.

[0550] <Example of light-emitting device configuration> As shown in Figure 37A, the light-emitting device has an EL layer 686 between a pair of electrodes (electrode 672, electrode 688). The EL layer 686 can be composed of multiple layers, such as layer 4420, light-emitting layer 4411, and layer 4430. 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 include, 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).

[0551] A configuration having a layer 4420, an emissive layer 4411, and a layer 4430 provided between a pair of electrodes can function as a single emissive unit, and in this specification, the configuration shown in Figure 37A is referred to as a single structure.

[0552] Figure 37B shows a modified example of the EL layer 686 of the light-emitting device shown in Figure 37A. Specifically, the light-emitting device shown in Figure 37B has a layer 4430-1 on electrode 672, a layer 4430-2 on layer 4430-1, a light-emitting layer 4411 on layer 4430-2, a layer 4420-1 on light-emitting layer 4411, a layer 4420-2 on layer 4420-1, and an electrode 688 on layer 4420-2. For example, when electrode 672 is the anode and electrode 688 is the cathode, layer 4430-1 functions as a hole injection layer, layer 4430-2 functions as a hole transport layer, layer 4420-1 functions as an electron transport layer, and layer 4420-2 functions as an electron injection layer. Alternatively, when electrode 672 is used as the cathode and electrode 688 as the anode, layer 4430-1 functions as an electron injection layer, layer 4430-2 functions as an electron transport layer, layer 4420-1 functions as a hole transport layer, and layer 4420-2 functions as a hole injection layer. By using such a layer structure, it is possible to efficiently inject carriers into the light-emitting layer 4411 and increase the efficiency of carrier recombination within the light-emitting layer 4411.

[0553] As shown in Figure 37C, a configuration in which multiple light-emitting layers (light-emitting layer 4411, light-emitting layer 4412, light-emitting layer 4413) are provided between layer 4420 and layer 4430 is also a variation of the single structure.

[0554] As shown in Figure 37D, a configuration in which multiple light-emitting units (EL layer 686a, EL layer 686b) are connected in series via an intermediate layer (charge generation layer) 4440 is referred to as a tandem structure in this specification. In this specification, the configuration shown in Figure 37D is referred to as a tandem structure, but it is not limited to this, and for example, a tandem structure may also be called a stack structure. Furthermore, by using a tandem structure, a light-emitting device capable of high-brightness light emission can be made.

[0555] Furthermore, in Figures 37C and 37D, as shown in Figure 37B, layer 4420 and layer 4430 may be a laminated structure consisting of two or more layers.

[0556] The light-emitting color of the light-emitting device can be red, green, blue, cyan, magenta, yellow, or white, depending on the material constituting the EL layer 686. Furthermore, the color purity can be further enhanced by adding a microcavity structure to the light-emitting device.

[0557] A light-emitting device that emits white light preferably has a configuration that includes two or more types of light-emitting materials in the light-emitting layer. To obtain white light emission, two types of light-emitting materials should be selected such that the light emitted by each of them 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 in color, a light-emitting device that emits white light as a whole can be obtained. When using three or more types of light-emitting materials, the light-emitting colors of each material should combine to produce white light emission as a whole. The same applies to light-emitting devices that have three or more light-emitting layers.

[0558] 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.

[0559] The configuration examples illustrated in this embodiment, and the corresponding drawings, etc., can be appropriately combined with other configuration examples or drawings, etc., at least in part.

[0560] This embodiment can be implemented in appropriate combination with other embodiments described herein, at least in part.

[0561] (Embodiment 4) This embodiment describes the configuration of a light-receiving and light-emitting device that can be used in a display device according to one aspect of the present invention. The display device described above can be configured with the addition of a light-receiving and light-emitting device. Alternatively, the light-receiving device can be replaced with a light-receiving and light-emitting device. A display device according to one aspect of the present invention can have, for example, a configuration comprising a light-emitting device, a light-receiving device, and a light-receiving and light-emitting device. Alternatively, a display device according to one aspect of the present invention can have a configuration comprising a light-emitting device and a light-receiving and light-emitting device.

[0562] A light-receiving and light-receiving device has both a light-emitting function and a light-receiving function. Here, we will explain using a light-receiving and light-receiving device that emits red light and has a light-receiving function as an example. Note that the method for manufacturing the light-receiving and light-receiving device can be found in the description of the method for manufacturing the light-receiving device mentioned above, so a detailed explanation will be omitted. Alternatively, the method for manufacturing the light-receiving and light-receiving device can be found in the description of the method for manufacturing the light-emitting device mentioned above, so a detailed explanation will be omitted.

[0563] 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.

[0564] In this embodiment, a top-emission type display device will be used as an example for explanation.

[0565] The light-receiving and light-emitting device shown in Figure 38A has an electrode 377, a hole injection layer 381, a hole transport layer 382, ​​an active layer 373, a light-emitting layer 383R, an electron transport layer 384, an electron injection layer 385, and an electrode 378 stacked in this order.

[0566] The light-emitting layer 383R has a light-emitting material that emits red light. The active layer 373 has an organic compound that absorbs visible light. Alternatively, the active layer 373 may have an organic compound that absorbs both visible light and infrared light. Alternatively, the active layer 373 may have an organic compound that absorbs both visible light and infrared light. It is preferable that the organic compound in the active layer 373 does not easily absorb at least the light emitted by the light-emitting layer 383R. As a result, red light can be efficiently extracted from the light-receiving device, and one or more of the following can be detected with high accuracy: light with a shorter wavelength than red (e.g., green light and blue light), and light with a longer wavelength than red (e.g., infrared light).

[0567] Figure 38A schematically shows how a light-emitting / receiving device functions as a light-emitting device. In Figure 38A, the red (R) light emitted from the light-emitting / receiving device is indicated by an arrow.

[0568] Figure 38B schematically shows how a light-receiving device functions as a light-receiving device. In Figure 38B, the blue light (B) and green light (G) incident on the light-receiving device are indicated by arrows.

[0569] The light-receiving and light-receiving device can detect light incident on it by applying a voltage between electrodes 377 and 378, generate an electric charge, and extract it as an electric current.

[0570] The light-receiving and light-emitting device can be described as a configuration in which an active layer 373 is added to the light-emitting device. In other words, by simply adding a step of depositing the active layer 373 to the manufacturing process of the light-emitting device, the light-receiving and light-emitting device can be formed in parallel with the formation of the light-emitting device. Furthermore, the light-emitting device and the light-receiving and light-emitting device can be formed on the same substrate. Therefore, without significantly increasing the manufacturing process, it is possible to add either or both imaging and sensing functions to the display unit.

[0571] The stacking order of the light-emitting layer 383R and the active layer 373 is not limited. Figures 38A and 38B show an example in which the active layer 373 is provided on the hole transport layer 382 and the light-emitting layer 383R is provided on the active layer 373. For example, the stacking order of the light-emitting layer 383R and the active layer 373 may be reversed.

[0572] The light-receiving and light-emitting device does not necessarily have at least one of the hole injection layer 381, hole transport layer 382, ​​electron transport layer 384, and electron injection layer 385. Furthermore, the light-receiving and light-emitting device may have other functional layers, such as a hole blocking layer or an electron blocking layer.

[0573] In a light-receiving and light-emitting device, it is preferable to use a conductive film that transmits visible light on the electrode that extracts light, and to use a conductive film that reflects visible light on the electrode that does not extract light.

[0574] The functions and materials of each layer constituting the light-emitting and light-receiving device are the same as those of each layer constituting the light-emitting device and the light-receiving device; therefore, a detailed explanation is omitted.

[0575] Figures 38C to 38G show examples of stacked structures for light-receiving and light-emitting devices.

[0576] The light-receiving and light-emitting device shown in Figure 38C includes an electrode 377, a hole injection layer 381, a hole transport layer 382, ​​a light-emitting layer 383R, an active layer 373, an electron transport layer 384, an electron injection layer 385, and an electrode 378.

[0577] Figure 38C shows an example in which a light-emitting layer 383R is provided on a hole transport layer 382, ​​and an active layer 373 is laminated on the light-emitting layer 383R.

[0578] As shown in Figures 38A to 38C, the active layer 373 and the light-emitting layer 383R may be in contact with each other.

[0579] It is preferable to provide a buffer layer between the active layer 373 and the light-emitting layer 383R. In this case, it is preferable that the buffer layer has hole transport and electron transport properties. For example, it is preferable to use a bipolar material for the buffer layer. Alternatively, at least one layer from among a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a hole blocking layer, and an electron blocking layer can be used as the buffer layer. Figure 38D shows an example in which a hole transport layer 382 is used as the buffer layer.

[0580] By providing a buffer layer between the active layer 373 and the light-emitting layer 383R, the transfer of excitation energy from the light-emitting layer 383R to the active layer 373 can be suppressed. Furthermore, the buffer layer can be used to adjust the optical path length (cavity length) of the microcavity structure. Therefore, a light-emitting / receiving device having a buffer layer between the active layer 373 and the light-emitting layer 383R can achieve high luminescence efficiency.

[0581] Figure 38E shows an example of a laminated structure in which a hole transport layer 382-1, an active layer 373, a hole transport layer 382-2, and an emissive layer 383R are stacked in that order on a hole injection layer 381. The hole transport layer 382-2 functions as a buffer layer. The hole transport layers 382-1 and 281-2 may contain the same material or different materials. Alternatively, a layer that can be used as a buffer layer as described above may be used instead of the hole transport layer 281-2. Furthermore, the positions of the active layer 373 and the emissive layer 383R may be swapped.

[0582] The light-receiving device shown in Figure 38F differs from the light-receiving device shown in Figure 38A in that it does not have a hole transport layer 382. Thus, the light-receiving device does not need to have at least one of the hole injection layer 381, hole transport layer 382, ​​electron transport layer 384, and electron injection layer 385. Furthermore, the light-receiving device may have other functional layers such as a hole blocking layer or an electron blocking layer.

[0583] The light-receiving and light-emitting device shown in Figure 38G differs from the light-receiving and light-emitting device shown in Figure 38A in that it does not have an active layer 373 and a light-emitting layer 383R, but has a layer 389 that serves as both a light-emitting layer and an active layer.

[0584] As a layer that serves as both an emissive layer and an active layer, for example, a layer can be used that includes three materials: an n-type semiconductor that can be used in the active layer 373, a p-type semiconductor that can be used in the active layer 373, and an emissive material that can be used in the emissive layer 383R.

[0585] Furthermore, it is preferable that the lowest energy absorption band of the absorption spectrum of the mixed material of n-type and p-type semiconductors and the maximum peak of the emission spectrum (PL spectrum) of the luminescent material do not overlap, and it is even more preferable that they are sufficiently far apart.

[0586] The configuration examples illustrated in this embodiment, and the corresponding drawings, etc., can be appropriately combined with other configuration examples or drawings, etc., at least in part.

[0587] This embodiment can be implemented in appropriate combination with other embodiments described herein, at least in part.

[0588] (Embodiment 5) This embodiment describes metal oxides (oxide semiconductors) that can be used in the OS transistor described in the above embodiment.

[0589] 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.

[0590] Metal oxides can be formed by chemical vapor deposition (CVD) methods such as sputtering, metal-organic chemical vapor deposition (MOCVD), or atomic layer deposition (ALD).

[0591] <Classification of crystal structures> Examples of crystalline structures for oxide semiconductors include amorphous (including completely amorphous), CAAC, nc, CAC (cloud-aligned composite), single crystal, and polycrystal.

[0592] 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.

[0593] 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.

[0594] 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.

[0595] <<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. Furthermore, non-single-crystal oxide semiconductors include polycrystalline oxide semiconductors, pseudo-amorphous oxide semiconductors (a-like OS: amorphous-like oxide semiconductors), amorphous oxide semiconductors, etc.

[0596] Here, we will explain the details of the CAAC-OS, nc-OS, and a-like OS mentioned above.

[0597] [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.

[0598] Each of the above-mentioned crystalline regions 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 one minute crystal, the maximum diameter of that crystalline region will be 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.

[0599] In In-M-Zn oxide (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). Indium and element M are mutually substitutable. Therefore, the (M,Zn) layer may contain indium. The In layer may also contain element M. The In layer may also contain Zn. This layered structure can be observed, for example, as a lattice image in high-resolution TEM (Transmission Electron Microscope) images.

[0600] When structural analysis of a CAAC-OS film is performed using, for example, an XRD instrument, 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 peak indicating c-axis orientation (value of 2θ) may vary depending on the type and composition of the metal elements constituting the CAAC-OS.

[0601] 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.

[0602] 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.

[0603] 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 effectively than In oxide.

[0604] 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.

[0605] [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 more), 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.

[0606] [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.

[0607] <<Oxide Semiconductor Composition>> Next, we will explain the details of CAC-OS mentioned above. Note that CAC-OS refers to the material composition.

[0608] [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 the 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.

[0609] 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.

[0610] Here, the atomic ratios of In, Ga, and Zn to the metal elements constituting the CAC-OS in In-Ga-Zn oxide are denoted as [In], [Ga], and [Zn], respectively. For example, in the CAC-OS of In-Ga-Zn oxide, the first region is the region where [In] is greater than the [In] in the composition of the CAC-OS film. The second region is the region where [Ga] is greater than the [Ga] in the composition of the CAC-OS film. 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.

[0611] 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.

[0612] Furthermore, a clear boundary may not be observed between the first region and the second region described above.

[0613] In in-Ga-Zn oxides, CAC-OS 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 fashion, with these regions existing randomly. Therefore, it is presumed that CAC-OS has a structure in which the metal elements are unevenly distributed.

[0614] 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.

[0615] 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.

[0616] 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.

[0617] 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.

[0618] Therefore, when CAC-OS is used in a transistor, the conductivity due to the first region and the insulation due to the second region work complementaryly to give CAC-OS a switching function (on / off function). In other words, CAC-OS has conductive function in part of the material, insulating function in part of the material, and semiconductor function as a whole. By separating the conductive function and the insulating function, both functions can be maximized. 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 achieved.

[0619] Transistors using CAC-OS are highly reliable. Therefore, CAC-OS is ideal for various semiconductor devices, including display devices.

[0620] Oxide semiconductors can take on diverse structures, each possessing different properties. One embodiment of the present invention may include two or more of the following: amorphous oxide semiconductors, polycrystalline oxide semiconductors, a-like OS, CAC-OS, nc-OS, and CAAC-OS.

[0621] <Transistors containing oxide semiconductors> Next, we will explain the case where the above oxide semiconductor is used in a transistor.

[0622] By using the above-mentioned oxide semiconductor in transistors, it is possible to realize transistors with high field-effect mobility. Furthermore, it is possible to realize highly reliable transistors.

[0623] It is preferable to use an oxide semiconductor with a low carrier concentration for the transistor. For example, the carrier concentration of an oxide semiconductor is 1 × 10⁻⁶. 17 cm -3 The following is preferably 1 × 10 15 cm -3 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.

[0624] High-purity intrinsic or substantially high-purity intrinsic oxide semiconductor films have a low defect level density, which may result in a low trap level density.

[0625] Charges trapped in the trap levels of oxide semiconductors can take a long time to disappear and sometimes behave like fixed charges. Therefore, transistors in which channel formation regions are formed in oxide semiconductors with a high density of trap levels may exhibit unstable electrical properties.

[0626] 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.

[0627] <Impurities> Here, we will explain the effects of various impurities in oxide semiconductors.

[0628] 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:

[0629] When alkali metals or alkaline earth metals are present in oxide semiconductors, they can 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:

[0630] 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 × 10⁻¹⁰. 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:

[0631] Since hydrogen contained in an oxide semiconductor reacts with oxygen bonded to a metal atom to form water, oxygen vacancies may be formed. When hydrogen enters these oxygen vacancies, electrons that are carriers ma...

Claims

[Claim 1] It comprises a light-receiving device, a first light-emitting device, and an insulating layer. The light-receiving device comprises a first electrode, a light-receiving layer, and a common electrode, stacked in this order. The first light-emitting device comprises a second electrode, a first EL layer, and the common electrode, stacked in this order. The light-receiving layer comprises a first functional layer, a second functional layer, and an active layer between the first functional layer and the second functional layer. The first functional layer comprises a first substance having hole transport properties, The second functional layer comprises a second substance having electron transport properties. The ends of the active layer, the first functional layer, and the second functional layer coincide or roughly coincide with each other. The first EL layer comprises a third functional layer, a fourth functional layer, and a first light-emitting layer between the third and fourth functional layers. The third functional layer comprises a third substance having hole transport properties. The fourth functional layer comprises a fourth substance having electron transport properties. The insulating layer has regions that are in contact with the side surface of the first functional layer, the side surface of the light-receiving layer, the side surface of the second functional layer, the side surface of the third functional layer, the side surface of the first EL layer, and the side surface of the fourth functional layer. The edges of the first light-emitting layer, the third functional layer, and the fourth functional layer coincide or substantially coincide with each other. The film thickness of the first light-emitting layer in the region in contact with the insulating layer is thinner than the film thickness of the first light-emitting layer in the region not in contact with the insulating layer. The end of the light-receiving layer is located inward from the end of the first electrode. The insulating layer has regions that are in contact with the side surface of the light-receiving layer and the upper and side surfaces of the first electrode. The end of the first EL layer is located inward from the end of the second electrode. The insulating layer is a display device having regions that are in contact with the side surface of the first EL layer and the upper surface and side surface of the second electrode.

Images