Display device

Abstract

Provided is a semiconductor device having a light detection function and a high-definition display unit. This display device has a light emitting device, a light receiving device, and a substrate. The light emitting device has a first electrode, a light emitting layer, a first electron transport layer, an electron injection layer, and a second electrode, which are laminated in this order on the substrate. The light receiving device has a third electrode, an active layer, a first hole transport layer, an electron injection layer, and a second electrode which are laminated on the substrate in this order. A first potential is applied to the first electrode. It is preferable that a second potential lower than the first potential be applied to the second electrode. It is preferable that a third potential higher than the second potential be applied to the third electrode.

Description

Display device, display module and electronic device

[0001] 1. Field of the Invention One embodiment of the present invention relates to a semiconductor device, a display device, a display module, and an electronic device. 2. Description of the Related Art One embodiment of the present invention relates to a manufacturing method of a display device.

[0002] One embodiment of the present invention is not limited to the above technical field, and examples of the technical field of one embodiment of the present invention include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, an electronic device, a lighting device, an input device (for example, a touch sensor), an input / output device (for example, a touch panel), a driving method thereof, or a manufacturing method thereof.

[0003] In recent years, information terminal devices such as mobile phones such as smartphones, tablet information terminals, and notebook PCs (personal computers) have become widespread. Such information terminal devices often contain personal information, and various authentication technologies have been developed to prevent unauthorized use. There is a demand for information terminal devices with various functions, such as an image display function, a touch sensor function, and a function for capturing fingerprints for authentication.

[0004] For example, Patent Document 1 discloses an electronic device that includes a fingerprint sensor in a push button switch section.

[0005] As a display device, for example, a light-emitting device having a light-emitting device has been developed. A light-emitting device (also called an EL device or an EL element) utilizing the electroluminescence (hereinafter referred to as EL) phenomenon has features such as being easily thin and lightweight, being capable of high-speed response to an input signal, and being capable of being driven by a DC constant voltage power supply, and is therefore applied to a display device.

[0006] US Patent Application Publication No. 2014 / 0056493

[0007] An object of one embodiment of the present invention is to provide a semiconductor device having a light detection function and a high-resolution display portion.An object of one embodiment of the present invention is to provide a semiconductor device having a light detection function and a high-resolution display portion.An object of one embodiment of the present invention is to provide a semiconductor device having a large display portion and a light detection function.An object of one embodiment of the present invention is to provide a highly reliable semiconductor device having a light detection function.

[0008] An object of one embodiment of the present invention is to provide a manufacturing method for a semiconductor device having a photodetection function and a high-resolution display portion.An object of one embodiment of the present invention is to provide a manufacturing method for a semiconductor device having a photodetection function and a high-resolution display portion.An object of one embodiment of the present invention is to provide a manufacturing method for a semiconductor device having a large display portion and a photodetection function.An object of one embodiment of the present invention is to provide a manufacturing method for a highly reliable semiconductor device having a photodetection function.An object of one embodiment of the present invention is to provide a manufacturing method for a semiconductor device having a photodetection function with high yield.

[0009] Note that the description of these problems does not preclude the existence of other problems. One embodiment of the present invention does not necessarily have to solve all of these problems. Problems other than these can be extracted from the description in the specification, drawings, and claims.

[0010] One embodiment of the present invention is a display device including a light-emitting device, a light-receiving device, and a substrate. The light-emitting device includes a first electrode, a light-emitting layer, a first electron-transport layer, an electron-injection layer, and a second electrode stacked in this order on the substrate. The light-receiving device includes a third electrode, an active layer, a first hole-transport layer, an electron-injection layer, and a second electrode stacked in this order on the substrate.

[0011] In the above-described display device, the light-emitting device preferably has a second hole transport layer between the first electrode and the light-emitting layer.

[0012] In the above-described display device, the light-receiving device preferably has a second electron transport layer between the third electrode and the active layer.

[0013] In the above-described display device, it is preferable that the light-emitting device has a function of emitting visible light, and the light-receiving device has a function of detecting visible light.

[0014] In the above-described display device, it is preferable that the light-emitting device has a function of emitting infrared light, and the light-receiving device has a function of detecting infrared light.

[0015] In the display device described above, the first electrode is preferably supplied with a first potential, the second electrode is preferably supplied with a second potential lower than the first potential, and the third electrode is preferably supplied with a third potential higher than the second potential.

[0016] In the above-described display device, the first electrode and the third electrode are preferably provided on the same surface.

[0017] The display device has a pixel unit including a plurality of first pixels, second pixels, third pixels, and fourth pixels. Preferably, the first pixels, second pixels, third pixels, and fourth pixels each include the light-emitting device or the light-receiving device. The pixel unit preferably includes a first array in a first direction, in which the second pixels, the first pixels, the second pixels, and the third pixels are repeatedly arranged in this order, and a second array in which the fourth pixels, the first pixels, the fourth pixels, and the third pixels are repeatedly arranged in this order. The first array and the second array are alternately arranged in a second direction perpendicular to the first direction. The pixel unit preferably includes a third array in which the second pixels and the fourth pixels are alternately arranged in the second direction, and a fourth array in which the first pixels and the third pixels are alternately arranged in the second direction. The third array and the fourth array are alternately arranged in the first direction.

[0018] In the above-described display device, the first pixel, the second pixel, and the third pixel preferably have light-emitting devices that emit light in different wavelength regions, and the fourth pixel preferably has a light-receiving device.

[0019] In the display device, the third pixel preferably has a light-emitting device that emits green light. The area of ​​the third pixel is preferably smaller than the area of ​​the first pixel. The area of ​​the third pixel is preferably smaller than the area of ​​the second pixel.

[0020] One aspect of the present invention is a display module including the display device described above and at least one of a connector and an integrated circuit.

[0021] One embodiment of the present invention is an electronic device including the above-described display module and at least one of a housing, a battery, a camera, a speaker, and a microphone.

[0022] According to one embodiment of the present invention, a semiconductor device having a light detection function and a high-resolution display portion can be provided. According to one embodiment of the present invention, a semiconductor device having a light detection function and a high-resolution display portion can be provided. According to one embodiment of the present invention, a semiconductor device having a large display portion and a light detection function can be provided. According to one embodiment of the present invention, a highly reliable semiconductor device having a light detection function can be provided.

[0023] According to one embodiment of the present invention, a method for manufacturing a semiconductor device having a photodetection function and a high-resolution display portion can be provided. According to one embodiment of the present invention, a method for manufacturing a semiconductor device having a photodetection function and a high-resolution display portion can be provided. According to one embodiment of the present invention, a method for manufacturing a semiconductor device having a large display portion and a photodetection function can be provided. According to one embodiment of the present invention, a method for manufacturing a highly reliable semiconductor device having a photodetection function can be provided. According to one embodiment of the present invention, a method for manufacturing a semiconductor device having a photodetection function with a high yield can be provided.

[0024] Note that the description of these effects does not preclude the existence of other effects. One embodiment of the present invention does not necessarily have all of these effects. Effects other than these can be extracted from the description in the specification, drawings, and claims.

[0025] FIGS. 1A to 1C are diagrams showing an example of the configuration of a display device. FIGS. 2A to 2D are diagrams showing an example of the configuration of a display device. FIGS. 3A to 3C are diagrams showing an example of the configuration of a display device. FIG. 4 is a diagram showing an example of the configuration of a display device. FIG. 5A is a diagram showing an example of the configuration of a display device. FIGS. 5B and 5C are circuit diagrams of pixel circuits. FIGS. 6A and 6B are timing charts explaining a method of driving a display device. FIGS. 7A and 7B are circuit diagrams of pixel circuits. FIGS. 8A to 8C are circuit diagrams of pixel circuits. FIG. 9 is a circuit diagram of a pixel circuit. FIGS. 10A and 10B are diagrams showing an example of the configuration of a display device. FIGS. 11A and 11B are diagrams showing an example of the configuration of a display device. FIGS. 12A and 12B are diagrams showing an example of the configuration of a display device. FIGS. 13A and 13B are diagrams showing an example of the configuration of a display device. FIGS. 14A, 14B, and 14D are cross-sectional views showing an example of a display device. FIGS. 14C and 14E are diagrams showing examples of images captured by the display device. FIG. 15 is a cross-sectional view showing an example of a display device. FIGS. 16A to 16C are cross-sectional views showing an example of a display device. FIGS. 17A to 17C are cross-sectional views showing an example of a display device. FIGS. 18A to 18C are views showing an example of a display device. FIGS. 19A to 19C are views showing an example of an electronic device. FIG. 20A is a top view showing an example of a display device. FIG. 20B is a cross-sectional view showing an example of a display device. FIGS. 21A to 21I are top views showing an example of a pixel. FIGS. 22A to 22E are top views showing an example of a pixel. FIGS. 23A and 23B are top views showing an example of a pixel. FIGS. 24A and 24B are top views showing an example of a pixel. FIGS. 25A and 25B are top views showing an example of a pixel. FIGS. 26A and 26B are top views showing an example of a pixel. FIGS. 27A and 27B are top views showing an example of a pixel. FIG. 28A is a top view showing an example of a display device. FIG. 28B is a cross-sectional view showing an example of a display device. 29A to 29F are top views illustrating an example of a manufacturing method of a display device. FIGS. 30A to 30C are cross-sectional views illustrating an example of a manufacturing method of a display device. FIGS. 31A to 31C are cross-sectional views illustrating an example of a manufacturing method of a display device. FIGS. 32A to 32C are cross-sectional views illustrating an example of a manufacturing method of a display device.33A and 33B are cross-sectional views showing an example of a method for manufacturing a display device. FIGS. 34A to 34C are cross-sectional views showing an example of a method for manufacturing a display device. FIGS. 35A to 35C are cross-sectional views showing an example of a method for manufacturing a display device. FIGS. 36A and 36B are cross-sectional views showing an example of a method for manufacturing a display device. FIGS. 37A to 37E are cross-sectional views showing an example of a method for manufacturing a display device. FIGS. 38A to 38F are cross-sectional views showing an example of a method for manufacturing a display device. FIG. 39 is a perspective view showing an example of a display device. FIG. 40A is a cross-sectional view showing an example of a display device. FIGS. 40B and 40C are cross-sectional views showing an example of a transistor. FIG. 41 is a cross-sectional view showing an example of a display device. FIGS. 42A and 42B are perspective views showing an example of a display module. FIG. 43 is a cross-sectional view showing an example of a display device. FIG. 44 is a cross-sectional view showing an example of a display device. FIG. 45 is a cross-sectional view showing an example of a display device. FIG. 46 is a cross-sectional view showing an example of a display device. FIG. 47 is a cross-sectional view showing an example of a display device. FIGS. 48A to 48D are diagrams showing an example of a transistor. 49A and 49B are diagrams showing an example of an electronic device. FIGS. 50A to 50D are diagrams showing an example of an electronic device. FIGS. 51A to 51F are diagrams showing an example of an electronic device. FIG. 52 is a diagram showing an example of a vehicle. FIGS. 53A and 53B are diagrams showing current density-voltage characteristics of a light receiving device. FIG. 54 is a diagram showing current density-voltage characteristics of a light receiving device. FIG. 55A is a diagram showing current density-voltage characteristics of a light receiving device. FIG. 55B is a diagram showing external quantum efficiency of a light receiving device. FIG. 56A is a diagram showing current density-voltage characteristics of a light receiving device. FIG. 56B is a diagram showing external quantum efficiency of a light receiving device.

[0026] The embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be readily understood by those skilled in the art that various changes can be made in form and detail without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the description of the embodiments shown below.

[0027] In the configuration of the invention described below, the same parts or parts having similar functions are denoted by the same reference numerals in different drawings, and repeated explanations thereof will be omitted. Furthermore, when referring to similar functions, the same hatching pattern may be used and no particular reference numeral may be assigned.

[0028] For ease of understanding, the position, size, range, etc. of each component shown in the drawings may not represent the actual position, size, range, etc. Therefore, the disclosed invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings.

[0029] It should be noted that the terms "film" and "layer" can be interchangeable depending on the circumstances. For example, the term "conductive layer" can be changed to the term "conductive film." Or, for example, the term "insulating film" can be changed to the term "insulating layer."

[0030] Embodiment 1 In this embodiment, a display device according to one embodiment of the present invention will be described.

[0031] A display device according to one embodiment of the present invention includes a display portion having a plurality of pixels arranged in a matrix, each of which includes a light-emitting device (also referred to as a light-emitting element) and a light-receiving device (also referred to as a light-receiving element).

[0032] The light-emitting device functions as a display device (also referred to as a display element). In a display device of one embodiment of the present invention, light-emitting devices are arranged in a matrix in a display portion, and an image can be displayed on the display portion. In addition, the display device of one embodiment of the present invention has a function of detecting light using a light-receiving device.

[0033] The light-emitting device preferably uses an EL device such as an OLED (organic light-emitting diode) or a QLED (quantum-dot light-emitting diode). Examples of light-emitting materials that the EL device has include fluorescent materials, phosphorescent materials, inorganic compounds (such as quantum dot materials), and thermally activated delayed fluorescence (thermally activated delayed fluorescence (TADF) materials). Furthermore, LEDs such as micro LEDs (light-emitting diodes) can also be used as the light-emitting device. Note that a material in which a singlet excited state and a triplet excited state are in thermal equilibrium may be used as the TADF material. Such TADF materials have a short emission lifetime (excitation lifetime), and therefore can suppress a decrease in efficiency in a high-brightness region of a light-emitting device.

[0034] In a display portion of a display device according to one embodiment of the present invention, light-receiving devices are arranged in a matrix. The display portion has an image display function and / or an imaging function. The display portion can be used as an image sensor or a touch sensor. That is, by detecting light in the display portion, an image can be captured or the proximity or contact of an object (such as a finger, a hand, or a pen) can be detected. Furthermore, the display device according to one embodiment of the present invention can use a light-emitting device as a light source for a sensor. Therefore, a light-receiving portion and a light source are not required separately from the display device, and the number of components in an electronic device can be reduced.

[0035] When the 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 the present embodiment can be used as a scanner.

[0036] For example, an image sensor can be used to acquire data related to biometric information such as fingerprints and palm prints. That is, a biometric authentication sensor can be built into the display device. By building a biometric authentication sensor into the display device, the number of components in the electronic device can be reduced compared to when a biometric authentication sensor is provided separately from the display device, and the electronic device can be made smaller and lighter.

[0037] When the light-receiving device is used as a touch sensor, the display device can detect the proximity or contact of an object using the light-receiving device.

[0038] A more specific example will be described below with reference to the drawings.

[0039] 1A shows a schematic cross-sectional view of a light-emitting device 11 and a light-receiving device 12 included in a display device 10 of one embodiment of the present invention.

[0040] The light-emitting device 11 has a function of emitting light (hereinafter also referred to as a light-emitting function). The light-emitting device 11 has an electrode 13A, an EL layer 17, and an electrode 15. The light-emitting device 11 is preferably an organic EL device (organic electroluminescent device). The EL layer 17 sandwiched between the electrode 13A and the electrode 15 has at least a light-emitting layer. The light-emitting layer contains a light-emitting material that emits light. Light is emitted from the EL layer 17 by applying a voltage between the electrode 13A and the electrode 15. The EL layer 17 may further have various layers such as a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a carrier blocking layer, an exciton blocking layer, and a charge generation layer.

[0041] The light-emitting device can emit light in red, green, blue, cyan, magenta, yellow, white, or the like, depending on the material of the EL layer 17. Furthermore, the color purity can be further improved by providing the light-emitting device with a microcavity structure.

[0042] The light-receiving device 12 has a function of detecting light (hereinafter also referred to as a light-receiving function). The light-receiving device 12 may be, for example, a pn-type or pin-type photodiode. The light-receiving device 12 has an electrode 13B, a light-receiving layer 19, and an electrode 15. The light-receiving layer 19 sandwiched between the electrode 13B and the electrode 15 has at least an active layer. The light-receiving device 12 functions as a photoelectric conversion device, and can generate charges by light incident on the light-receiving layer 19 and extract them as a current. At this time, a voltage may be applied between the electrode 13B and the electrode 15. The amount of generated charges is determined based on the amount of light incident on the light-receiving layer 19.

[0043] The light receiving device 12 has a function of detecting visible light. The light receiving device 12 is sensitive to visible light. It is more preferable that the light receiving device 12 has a function of detecting visible light and infrared light. It is preferable that the light receiving device 12 is sensitive to visible light and infrared light.

[0044] In this specification, the blue (B) wavelength region is 400 nm or more and less than 490 nm, and the blue (B) light has at least one emission spectrum peak in this wavelength region. The green (G) wavelength region is 490 nm or more and less than 580 nm, and the green (G) light has at least one emission spectrum peak in this wavelength region. The red (R) wavelength region is 580 nm or more and less than 700 nm, and the red (R) light has at least one emission spectrum peak in this wavelength region. Furthermore, in this specification, the visible light wavelength region is 400 nm or more and less than 700 nm, and the visible light has at least one emission spectrum peak in this wavelength region. The infrared (IR) wavelength region is 700 nm or more and less than 900 nm, and the infrared (IR) light has at least one emission spectrum peak in this wavelength region.

[0045] The active layer includes 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 including an organic semiconductor as the light-receiving device 12. Organic photodiodes are easily made thin, lightweight, and large-area, and have a high degree of freedom in shape and design, making them applicable to a variety of display devices. Furthermore, using an organic semiconductor is preferable because the EL layer of the light-emitting device 11 and the light-receiving layer of the light-receiving device 12 can be formed by the same method (e.g., vacuum deposition), allowing the use of common manufacturing equipment.

[0046] A display device according to one embodiment of the present invention can suitably use an organic EL device as the light-emitting device 11 and an organic photodiode as the light-receiving device 12. The organic EL device and the organic photodiode can be formed on the same substrate. Therefore, an organic photodiode can be built into a display device using an organic EL device. The display device according to one embodiment of the present invention has one or both of an imaging function and a sensing function in addition to a function of displaying an image.

[0047] 1A shows a configuration in which the electrodes 13A and 13B are provided on a substrate 23. The electrodes 13A and 13B can be formed, for example, by processing a conductive film formed on the substrate 23 into an island shape. In other words, the electrodes 13A and 13B can be formed through the same process.

[0048] The substrate 23 may be a heat-resistant substrate that can withstand the formation of the light-emitting device 11 and the light-receiving device 12. When an insulating substrate is used as the substrate 23, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, an organic resin substrate, or the like may be used. In addition, a semiconductor substrate such as a single-crystal semiconductor substrate made of silicon or silicon carbide, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, or an SOI substrate may be used.

[0049] In particular, it is preferable to use a substrate having a semiconductor circuit including semiconductor elements such as transistors formed on the aforementioned insulating substrate or semiconductor substrate as the substrate 23. The semiconductor circuit preferably comprises, 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.

[0050] The electrode 13A and the electrode 13B can each be referred to as a pixel electrode. The electrode 15 is a layer common to the light-emitting device 11 and the light-receiving device 12, and can be referred to as a common electrode. Of the pixel electrode and the common electrode, the electrode that emits light or that receives light uses a conductive film that transmits visible light and infrared light. It is preferable to use a conductive film that reflects visible light and infrared light for the electrode that does not emit light or that does not receive light.

[0051] In the display device according to one embodiment of the present invention, the electrode 15 functioning as a common electrode functions as one of an anode and a cathode in the light-emitting device 11 and functions as the other of the anode and the cathode in the light-receiving device 12 .

[0052] 1B schematically shows a configuration in which, in the light-emitting device 11, the electrode 13A functions as an anode and the electrode 15 functions as a cathode, and, in the light-receiving device 12, the electrode 13B functions as a cathode and the electrode 15 functions as an anode. In order to make it easier to understand the orientation of the anode and cathode, in FIG. 1B , the circuit symbol for a light-emitting diode is shown on the left side of the light-emitting device 11, and the circuit symbol for a photodiode is shown on the right side of the light-receiving device 12. In addition, electrons are indicated by circles with a - (minus) sign, holes are indicated by circles with a + (plus) sign, and the flow directions of the electrons and holes are schematically shown by arrows.

[0053] In the light-emitting device 11, the electrode 13A functions as an anode and is electrically connected to a first wiring that supplies a first potential. In the light-emitting device 11, the electrode 15 functions as a cathode and is electrically connected to a second wiring that supplies a second potential. The second potential is lower than the first potential.

[0054] In the light-receiving device 12, the electrode 13B functions as a cathode and is electrically connected to a third wiring that supplies a third potential. In the light-receiving device 12, the electrode 15 functions as an anode and is electrically connected to a second wiring that supplies a second potential. A reverse bias voltage is applied to the light-receiving device 12. In other words, the third potential is higher than the second potential.

[0055] In the light-emitting device 11, the electrode 13A functions as an anode and the electrode 15 functions as a cathode, and in the light-receiving device 12, the electrode 13B functions as a cathode and the electrode 15 functions as an anode, thereby making it possible to reduce the potential difference between the electrodes 13A and 13B and suppress leakage between the electrodes 13A and 13B (hereinafter also referred to as side leakage), thereby making it possible to provide a light-receiving device with a high signal-to-noise ratio (SNR).

[0056] For example, the first potential (potential supplied to electrode 13A) can be 12 V, the second potential (potential supplied to electrode 15) can be 0 V, and the third potential (potential supplied to electrode 13B) can be 4 V. With this configuration, the potential difference between electrode 13A and electrode 13B can be reduced, and side leakage between light-emitting device 11 and light-receiving device 12 can be suppressed.

[0057] Furthermore, since the difference between the highest and lowest potentials of the first potential (potential supplied to electrode 13A), the second potential (potential supplied to electrode 15), and the third potential (potential supplied to electrode 13B) can be reduced, a display device with low power consumption can be obtained.

[0058] In the display device of one embodiment of the present invention, side leakage between the light-emitting device 11 and the light-receiving device 12 is suppressed, and therefore the distance between the light-emitting device 11 and the light-receiving device 12 can be narrowed. That is, the ratio of the light-emitting device 11 and the light-receiving device 12 to the pixel (hereinafter also referred to as the aperture ratio) can be increased. Furthermore, the pixel size can be reduced, and the resolution of the display device can be increased. Therefore, a display device having a light detection function and a high aperture ratio can be realized. Furthermore, a display device having a light detection function and high resolution can be realized.

[0059] Note that the resolution of the light-receiving device 12 can be 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. In particular, when the light-receiving device 12 is arranged with a resolution of 200 ppi to 600 ppi, preferably 300 ppi to 600 ppi, the light-receiving device 12 can be suitably used for imaging a fingerprint. When fingerprint authentication is performed using the display device of one embodiment of the present invention, increasing the resolution of the light-receiving device 12 enables, for example, extraction of fingerprint minutia with high accuracy, 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). If the resolution of the light-receiving device is assumed to be 500 ppi, one pixel has a size of 50.8 μm, which is sufficient resolution for capturing an image of the width of a fingerprint (typically, 300 μm to 500 μm).

[0060] Alternatively, the display device 10 according to one embodiment of the present invention may be configured such that, in the light-emitting device 11, the electrode 13A functions as a cathode and the electrode 15 functions as an anode, and in the light-receiving device 12, the electrode 13B functions as an anode and the electrode 15 functions as a cathode, as shown in FIG. 1C.

[0061] In the light-emitting device 11, the electrode 13A functions as a cathode and is electrically connected to a first wiring that supplies a first potential. In the light-emitting device 11, the electrode 15 functions as an anode and is electrically connected to a second wiring that supplies a second potential. The second potential is higher than the first potential.

[0062] In the light-receiving device 12, the electrode 13B functions as an anode and is electrically connected to a third wiring that supplies a third potential. In the light-receiving device 12, the electrode 15 functions as a cathode and is electrically connected to a second wiring that supplies a second potential. A reverse bias voltage is applied to the light-receiving device 12. In other words, the third potential is lower than the second potential. With this configuration, the potential difference between the electrodes 13A and 13B can be reduced, and leakage between the electrodes 13A and 13B can be suppressed.

[0063] FIG. 2A shows an example different from the display device 10 described above. The display device 10A shown in FIG. 2A includes a light-emitting device 11a and a light-receiving device 12a. The display device 10A differs from the display device 10 described above mainly in that the light-emitting device 11a includes a layer 21 between the EL layer 17 and the electrode 15, and the light-receiving device 12a includes a layer 21 between the light-receiving layer 19 and the electrode 15. The layer 21 is a layer common to the light-emitting device 11a and the light-receiving device 12a, and can be referred to as a common layer. For example, it is preferable that at least one of the hole injection layer, hole transport layer, electron transport layer, and electron injection layer be a layer common to the light-receiving device and the light-emitting device.

[0064] 2A , in the light-emitting device 11a, the electrode 13A functions as an anode and the electrode 15 functions as a cathode, and in the light-receiving device 12a, the electrode 13B functions as a cathode and the electrode 15 functions as an anode, the layer 21 includes, for example, a layer containing a substance with high electron injection properties (electron injection layer). The layer 21 can function as an electron injection layer that injects electrons from the electrode 15, which functions as a cathode, into the EL layer 17 in the light-emitting device 11a.

[0065] The layer 21, which includes a layer containing a substance with high electron injection properties (electron injection layer), does not have a specific function in the light-receiving device 12a. As described above, the layer 21 may be configured to function as an electron injection layer in the light-emitting device 11a.

[0066] A layer shared by a light-receiving device and a light-emitting device may have different functions in the light-emitting device and in the light-receiving device. In this specification, components may be referred to based on their functions in the light-emitting device. For example, a hole injection layer functions as a hole injection layer in the light-emitting device and as a hole transport layer in the light-receiving device. Similarly, an electron injection layer functions as an electron injection layer in the light-emitting device and as an electron transport layer in the light-receiving device. Furthermore, a layer shared by a light-receiving device and a light-emitting device may have the same functions in the light-emitting device and in the light-receiving device. A hole transport layer functions as a hole transport layer in both the light-emitting device and the light-receiving device, and an electron transport layer functions as an electron transport layer in both the light-emitting device and the light-receiving device.

[0067] 2B , in the light-emitting device 11a, the electrode 13A functions as a cathode and the electrode 15 functions as an anode, and in the light-receiving device 12a, the electrode 13B functions as an anode and the electrode 15 functions as a cathode, the layer 21 includes, for example, a layer containing a substance with high hole injection properties (hole injection layer). The layer 21 can function as a hole injection layer that injects holes from the electrode 15, which functions as an anode, into the EL layer 17 in the light-emitting device 11a.

[0068] The layer 21, which includes a layer containing a substance with high hole injection properties (hole injection layer), does not have a specific function in the light-receiving device 12a. As described above, the layer 21 may be configured to function as a hole injection layer in the light-emitting device 11a.

[0069] 2C shows a display device according to one embodiment of the present invention. A display device 10B shown in FIG. 2C includes a light-emitting device 11b and a light-receiving device 12b. The EL layer 17 of the light-emitting device 11b has a stacked structure in which a layer 31A, a light-emitting layer 41, and a layer 37A are stacked in this order. The light-receiving layer 19 of the light-receiving device 12b has a stacked structure in which a layer 37B, an active layer 43, and a layer 31B are stacked in this order.

[0070] In the light-emitting device 11b, the electrode 13A functions as an anode, and the electrode 15 functions as a cathode. In the light-receiving device 12, the electrode 13B functions as a cathode, and the electrode 15 functions as an anode. The layer 21 includes, for example, a layer containing a material with high electron injection properties (electron injection layer).

[0071] The layer 31A and the layer 31B each include, for example, a layer containing a substance with high hole-transport properties (hole-transport layer). Furthermore, the layer 31A and the layer 31B may each include a layer containing a substance with high hole-injection properties (hole-injection layer). When the layer 31A and the layer 31B each include a substance with high hole-transport properties, the substance with high hole-transport properties in the layer 31A and the substance with high hole-transport properties in the layer 31B may be the same as or different from each other. Similarly, when the layer 31A and the layer 31B each include a substance with high hole-injection properties, the substance with high hole-injection properties in the layer 31A and the substance with high hole-injection properties in the layer 31B may be the same as or different from each other. Furthermore, the layer 31A and the layer 31B may each have a stacked structure.

[0072] The layer 37A and the layer 37B each include, for example, a layer containing a substance with high electron transport properties (electron transport layer). Furthermore, the layer 37A and the layer 37B may each include a layer containing a substance with high electron injection properties (electron injection layer). When the layer 37A and the layer 37B each include a substance with high electron transport properties, the substance with high electron transport properties in the layer 37A and the substance with high electron transport properties in the layer 37B may be the same or different. Similarly, when the layer 37A and the layer 37B each include a substance with high electron injection properties, the substance with high electron injection properties in the layer 37A and the substance with high electron injection properties in the layer 37B may be the same or different. Furthermore, the layer 37A and the layer 37B may each have a stacked structure.

[0073] The active layer 43 includes a semiconductor, and it is particularly preferable that the active layer 43 includes an organic semiconductor.

[0074] The light-emitting layer 41 contains a light-emitting material that emits light. In the light-emitting device 11, the structure including the layer 31A, the light-emitting layer 41, and the layer 37A provided between the pair of electrodes (electrode 13A and electrode 15) can function as a single light-emitting unit, and the structure of the light-emitting device 11b may be referred to as a single structure in this specification and the like.

[0075] The light-emitting device 11b includes, in order from the electrode 13A side, a layer 31A including a layer containing a substance with high hole transport properties (hole transport layer), a light-emitting layer 41, and a layer 37A including a layer containing a substance with high electron transport properties (electron transport layer). The light-receiving device 12b includes, in order from the electrode 13B side, a layer 37B including a layer containing a substance with high electron transport properties (electron transport layer), an active layer 43, and a layer 31B including a layer containing a substance with high hole transport properties (hole transport layer). In a display device according to one embodiment of the present invention, the stacking order of the layer containing a substance with high electron transport properties (electron transport layer) and the layer containing a substance with high hole transport properties (hole transport layer), sandwiching the light-emitting layer and the active layer, is reversed between the light-emitting device and the light-receiving device. This configuration can suppress side leakage between the light-emitting device and the light-receiving device.

[0076] The configuration of a display device different from the display device 10B described above is shown in Fig. 2D. The display device 10C shown in Fig. 2D has a light-emitting device 11c and a light-receiving device 12c. The light-emitting device 11c differs from the light-emitting device 11b described above mainly in that the layer stacking order of the layers constituting the EL layer 17 is reversed. The light-receiving device 12c differs from the light-receiving device 12b described above mainly in that the layer stacking order of the layers constituting the light-receiving layer 19 is reversed.

[0077] The EL layer 17 of the light-emitting device 11c has a layered structure in which a layer 37A, a light-emitting layer 41, and a layer 31A are stacked in this order. The light-receiving layer 19 of the light-receiving device 12c has a layered structure in which a layer 31B, an active layer 43, and a layer 37B are stacked in this order.

[0078] In the light-emitting device 11b, the electrode 13A functions as a cathode, and the electrode 15 functions as an anode. In the light-receiving device 12, the electrode 13B functions as an anode, and the electrode 15 functions as a cathode. The layer 21 includes, for example, a layer containing a material with high hole injection properties (hole injection layer).

[0079] The following describes a configuration that differs from the display device described above, taking as an example a configuration in which the electrode 13A functions as an anode and the electrode 15 functions as a cathode in the light-emitting device, and the electrode 13B functions as a cathode and the electrode 15 functions as an anode in the light-receiving device.

[0080] 3A illustrates a display device according to one embodiment of the present invention. A display device 10D illustrated in FIG. 3A includes a light-emitting device 11d and a light-receiving device 12b. The light-emitting device 11d includes a light-emitting layer 41 having a stacked structure in which a light-emitting layer 41a, a light-emitting layer 41b, and a light-emitting layer 41c are stacked in this order. A structure in which multiple light-emitting layers (e.g., a light-emitting layer 41a, a light-emitting layer 41b, and a light-emitting layer 41c) are provided between the layer 31A and the layer 37A can also be referred to as a single structure.

[0081] A display device according to one embodiment of the present invention is shown in Fig. 3B. A display device 10E shown in Fig. 3B includes a light-emitting device 11e and a light-receiving device 12e.

[0082] The light-emitting device 11e differs from the light-emitting device 11b in that the layer 31A has a stacked structure of a layer 33A and a layer 35A on the layer 33A. The light-receiving device 12e differs from the light-receiving device 12b in that the layer 31B has a stacked structure of a layer 35B and a layer 33B on the layer 35B.

[0083] The layer 33A and the layer 33B each include, for example, a layer containing a substance with high hole injection properties (hole injection layer). The substance with high hole injection properties contained in the layer 33A and the substance with high hole injection properties contained in the layer 33B may be the same as or different from each other.

[0084] The layer 35A and the layer 35B each include, for example, a layer containing a substance with a high hole-transport property (a hole-transport layer). The substance with a high hole-transport property contained in the layer 35A and the substance with a high hole-transport property contained in the layer 35B may be the same as or different from each other.

[0085] Such a layer structure enables the light-emitting device 11e to efficiently inject carriers into the light-emitting layer 41 and to increase the efficiency of carrier recombination in the light-emitting layer 41. As described above, in the light-receiving device 12e, the layer 33B functions as a hole transport layer.

[0086] A display device according to one embodiment of the present invention is shown in Fig. 3C. A display device 10F shown in Fig. 3C includes a light-emitting device 11f and a light-receiving device 12f.

[0087] The light-emitting device 11f differs from the light-emitting device 11e described above mainly in that it has an optical adjustment layer 39A between the electrode 13A and the EL layer 17. The light-receiving device 12f differs from the light-receiving device 12e described above mainly in that it has an optical adjustment layer 39B between the electrode 13B and the light-receiving layer 19.

[0088] The optical adjustment layers 39A and 39B are preferably made of a conductive material that is highly transparent to visible light. It is even more preferable that the optical adjustment layers 39A and 39B are made of a conductive material that is highly transparent to visible light and infrared light. The optical adjustment layers 39A and 39B can be made of a conductive oxide such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, zinc oxide containing gallium, indium tin oxide containing silicon, or indium zinc oxide containing silicon.

[0089] Here, electrodes 13A and 13B are made of conductive films that are reflective to visible light, and electrode 15 is made of a conductive film that is reflective and transparent to visible light. This allows the light-emitting device 11f and the light-receiving device 12f to have a so-called microcavity structure (a microresonator structure). The light-emitting device 11f can be a light-emitting device with high color purity by intensifying light of a specific wavelength. The light-receiving device 12f can be a light-receiving device with high sensitivity by intensifying light of a specific wavelength to be detected.

[0090] The optical path lengths of the light-emitting device 11f and the light-receiving device 12f can be made different by making the optical adjustment layer 39A and the optical adjustment layer 39B have different thicknesses. Each optical adjustment layer may be a conductive film having a different thickness, or may have a single-layer structure or a multiple-layer structure.

[0091] A display device according to one embodiment of the present invention is shown in Fig. 4. A display device 10G shown in Fig. 4 includes a light-emitting device 11g and a light-receiving device 12b.

[0092] The light-emitting device 11g has a layered structure in which an EL layer 47, an intermediate layer 50, and an EL layer 17 are stacked in this order between an electrode 13A and an electrode 15. The EL layer 47 has a layered structure in which a layer 51A, a light-emitting layer 61, and a layer 57A are stacked in this order.

[0093] The layer 51A, the light-emitting layer 61, and the layer 57A may each have a stacked structure. The description of the layer 31A can be referred to for the layer 51A, and therefore a detailed description thereof will be omitted. The description of the light-emitting layer 61 can be referred to for the light-emitting layer 41, and therefore a detailed description thereof will be omitted. The description of the layer 37A can be referred to for the layer 57A, and therefore a detailed description thereof will be omitted.

[0094] A configuration in which multiple light-emitting units (EL layer 17 and EL layer 47) are connected in series via an intermediate layer 50 (also referred to as a charge generation layer), such as light-emitting device 11g, may be referred to as a tandem structure in this specification. The tandem structure may also be referred to as a stack structure. The tandem structure allows for a light-emitting device capable of emitting light with high brightness.

[0095] The light-emitting color of the light-emitting device can be red, green, blue, cyan, magenta, yellow, white, or the like, depending on the combination of the material constituting the EL layer 17 and the material constituting the EL layer 47. Furthermore, the color purity can be further improved by providing the light-emitting device with a microcavity structure.

[0096] A light-emitting device that emits white light preferably has a configuration in which the light-emitting layer 41 contains two or more types of light-emitting materials. When using a configuration containing two light-emitting materials, the light-emitting materials may be selected so that the emitted light has a complementary color relationship. For example, by making the emitted color of the first light-emitting material and the emitted color of the second light-emitting material complementary, a light-emitting device that emits white light as a whole can be obtained. When using a configuration containing three or more light-emitting materials, the white light can be emitted by mixing the emitted colors of the respective light-emitting materials. Similarly, a light-emitting device having two or more light-emitting layers can be configured to emit white light by mixing the emitted colors of the respective light-emitting layers. For example, the light-emitting device 11d shown in FIG. 3A can be realized as a single-structure white light-emitting device by mixing the emitted colors of the light-emitting layers 41a, 41b, and 41c.

[0097] The light-emitting layer preferably contains two or more light-emitting materials that emit light of R (red), G (green), B (blue), Y (yellow), O (orange), etc. Alternatively, it is preferable that the light-emitting layer contains two or more light-emitting materials, and the light emitted by each of the light-emitting materials contains spectral components of two or more colors of R, G, and B.

[0098] The combination of the light-emitting device and the light-receiving device is not particularly limited. A display device may include one or more of the light-emitting devices described above and one or more of the light-receiving devices described above. For example, a display device may include the light-emitting device 11e and the light-receiving device 12c.

[0099] 5A shows a block diagram of the display device 100. The display device 100 includes a display unit 71, a drive circuit unit 72, a drive circuit unit 73, a drive circuit unit 74, a circuit unit 75, and the like.

[0100] The display unit 71 has a plurality of pixels 80 arranged in a matrix. Each pixel 80 has sub-pixels 81R, 81G, 81B, and 82PS. The sub-pixels 81R, 81G, and 81B each have a light-emitting device that functions as a display device. For example, any of the light-emitting devices described above can be used as the light-emitting device. The sub-pixel 82PS has a light-receiving device that functions as a photoelectric conversion element. For example, any of the light-receiving devices described above can be used as the light-receiving device.

[0101] In this specification, the smallest unit within a single "pixel" that performs independent operation is defined as a "sub-pixel" for convenience in the explanation, but "pixel" may be replaced with "region" and "sub-pixel" may be replaced with "pixel".

[0102] The pixel 80 is electrically connected to a wiring GL, a wiring SLR, a wiring SLG, a wiring SLB, a wiring TX, a wiring SE, a wiring RS, a wiring WX, and the like. The wirings SLR, SLG, and SLB are electrically connected to a driver circuit unit 72. The wiring GL is electrically connected to a driver circuit unit 73. The driver circuit unit 72 functions as a source line driver circuit (also referred to as a source driver). The driver circuit unit 73 functions as a gate line driver circuit (also referred to as a gate driver).

[0103] The pixel 80 has sub-pixels 81R, 81G, and 81B as sub-pixels having light-emitting devices. For example, the sub-pixel 81R is a sub-pixel that exhibits red, the sub-pixel 81G is a sub-pixel that exhibits green, and the sub-pixel 81B is a sub-pixel that exhibits blue. This allows the display device 100 to display full color. Note that, although an example in which the pixel 80 has sub-pixels of three colors is shown here, the pixel 80 may have sub-pixels of four or more colors.

[0104] Sub-pixel 81R has a light-emitting device that emits red light. Sub-pixel 81G has a light-emitting device that emits green light. Sub-pixel 81B has a light-emitting device that emits blue light. Note that pixel 80 may have sub-pixels that have light-emitting devices that emit light of other colors. For example, pixel 80 may have, in addition to the above three sub-pixels, a sub-pixel that has a light-emitting device that emits white light, or a sub-pixel that has a light-emitting device that emits yellow light.

[0105] The wiring GL is electrically connected to the sub-pixels 81R, 81G, and 81B arranged in the row direction (extension direction of the wiring GL). The wiring SLR, wiring SLG, and wiring SLB are electrically connected to the sub-pixels 81R, 81G, and 81B arranged in the column direction (extension direction of the wiring SLR, etc.), respectively.

[0106] The sub-pixel 82PS of the pixel 80 is electrically connected to a wiring TX, a wiring SE, a wiring RS, and a wiring WX. The wiring TX, the wiring SE, and the wiring RS are each electrically connected to the drive circuit unit 74, and the wiring WX is electrically connected to the circuit unit 75.

[0107] The drive circuit unit 74 has a function of generating signals for driving the sub-pixels 82PS and outputting them to the sub-pixels 82PS via the wirings SE, TX, and RS. The circuit unit 75 has a function of receiving signals output from the sub-pixels 82PS via the wirings WX and outputting them to the outside as image data. The circuit unit 75 functions as a readout circuit.

[0108] <Configuration Example of Pixel Circuit> FIG. 5B shows an example of a circuit diagram of a pixel 81 that can be applied to the sub-pixels 81R, 81G, and 81B. The pixel 81 includes a transistor M11, a transistor M12, a transistor M13, a capacitor C11, and a light-emitting device EL. A wiring GL and a wiring SL are electrically connected to the pixel 81. The wiring SL corresponds to any one of the wirings SLR, SLG, and SLB shown in FIG. 5A. Any one of the light-emitting devices described above can be used as the light-emitting device EL.

[0109] The transistor M11 has a gate electrically connected to a wiring GL, one of a source and a drain electrically connected to a wiring SL, and the other electrically connected to one electrode of a capacitor C11 and the gate of the transistor M12. The transistor M12 has one of a source and a drain electrically connected to a wiring EAL, and the other of a source and a drain electrically connected to one electrode of a light-emitting device EL, the other electrode of the capacitor C11, and one of a source and a drain of the transistor M13. The transistor M13 has a gate electrically connected to a wiring GL, and the other of a source and a drain electrically connected to a wiring RL. The light-emitting device EL has the other electrode electrically connected to a wiring ACL.

[0110] The transistors M11 and M13 function as switches, and the transistor M12 functions as a transistor for controlling the current flowing through the light-emitting device EL.

[0111] Here, it is preferable that all of the transistors M11 to M13 be transistors having silicon in their channel formation regions (hereinafter referred to as Si transistors). Alternatively, it is preferable that the transistors M11 to M13 be transistors having metal oxide (also referred to as oxide semiconductor) in their channel formation regions (hereinafter referred to as OS transistors), and the transistor M12 be a Si transistor.

[0112] Examples of silicon include single-crystal silicon, polycrystalline silicon, and amorphous silicon. Si transistors have high field-effect mobility and good frequency characteristics. For example, a transistor having low-temperature polysilicon (LTPS) in a channel formation region (hereinafter referred to as an LTPS transistor) can be used.

[0113] By using Si transistors, circuits that need to be driven at high frequencies (such as source driver circuits) can be built on the same substrate as the display unit, simplifying the external circuits mounted on the display device and reducing component and mounting costs.

[0114] The oxide semiconductor preferably contains, for example, indium, a metal M (M is one or more selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more selected from aluminum, gallium, yttrium, and tin. In particular, an oxide containing indium, gallium, and zinc (also referred to as IGZO) is preferably used for the semiconductor layer of the OS transistor. Alternatively, an oxide containing indium, tin, and zinc is preferably used. Alternatively, an oxide containing indium, gallium, tin, and zinc is preferably used.

[0115] An OS transistor using an oxide semiconductor having a wider band gap and a lower carrier density than silicon can achieve an extremely small off-state current. Therefore, the small off-state current allows charge stored in a capacitor connected in series with the OS transistor to be held for a long period of time. Therefore, it is preferable to use OS transistors for the transistors M11 and M13 connected in series with the capacitor C11. Using OS transistors as the transistors M11 and M13 can prevent charge stored in the capacitor C11 from leaking through the transistor M11 or M13. Furthermore, because charge stored in the capacitor C11 can be held for a long period of time, a still image can be displayed for a long period of time without rewriting data in the pixel 81.

[0116] A data potential is applied to the wiring SL, and a selection signal is applied to the wiring GL. The selection signal includes a potential that turns on a transistor and a potential that turns off a transistor.

[0117] A reset potential is applied to the wiring RL. A first potential is applied to the wiring EAL. A second potential is applied to the wiring ACL. The wiring EAL is electrically connected to the anode of the light-emitting device EL and functions to supply a first potential to the anode of the light-emitting device EL. The wiring ACL is electrically connected to the cathode of the light-emitting device EL and functions to supply a second potential to the cathode of the light-emitting device EL. The second potential is lower than the first potential. In the pixel 81, the first potential can be referred to as the anode potential, and the second potential can be referred to as the cathode potential. The reset potential applied to the wiring RL can be a potential such that the potential difference between the reset potential and the cathode potential is smaller than the threshold voltage of the light-emitting device EL. The reset potential can be a potential higher than the cathode potential, the same as the cathode potential, or a potential lower than the cathode potential.

[0118] 5C shows an example of a circuit diagram applicable to the sub-pixel 82PS. The pixel 82 includes transistors M15, M16, M17, and M18, a capacitor C21, and a light-receiving device PD. The light-receiving device PD can be any of the light-receiving devices described above.

[0119] The transistor M15 has a gate electrically connected to a wiring TX, one of a source and a drain electrically connected to a cathode of the light-receiving device PD, and the other of the source and drain electrically connected to one of a source and a drain of the transistor M16, a first electrode of the capacitor C21, and the gate of the transistor M17. The transistor M16 has a gate electrically connected to a wiring RS, and the other of the source and drain electrically connected to a wiring V11. The transistor M17 has one of a source and a drain electrically connected to a wiring V13, and the other of the source and drain electrically connected to one of a source and a drain of the transistor M18. The transistor M18 has a gate electrically connected to a wiring SE, and the other of the source and drain electrically connected to a wiring WX. The light-receiving device PD has an anode electrically connected to a wiring ACL. The capacitor C21 has a second electrode electrically connected to a wiring V12.

[0120] In pixel 82, the wiring ACL electrically connected to the anode of the light-receiving device PD can be common to the wiring ACL of pixel 81, and is supplied with a second potential. In pixel 82, the wiring ACL has a function of supplying the second potential to the anode of the light-receiving device PD. A third potential is supplied to the wiring V11. The wiring V11 is electrically connected to the cathode of the light-receiving device PD, and has a function of supplying the third potential to the cathode of the light-receiving device PD. The third potential is higher than the second potential. This allows a reverse bias voltage to be applied to the light-receiving device PD.

[0121] The transistors M15, M16, and M18 function as switches, and the transistor M17 functions as an amplifier.

[0122] It is preferable that all of the transistors M15 to M18 be Si transistors. Alternatively, it is preferable that the transistors M15 and M16 be OS transistors and the transistor M17 be a Si transistor. In this case, the transistor M18 may be either an OS transistor or a Si transistor.

[0123] By using OS transistors for the transistors M15 and M16, it is possible to prevent the potential held at the gate of the transistor M17, which is generated by charge in the light-receiving device PD, from leaking through the transistor M15 or the transistor M16.

[0124] For example, when imaging using the global shutter system, the period from the end of the charge transfer operation to the start of the readout operation (charge retention period) differs depending on the pixel. Here, capturing an image in which all pixels have the same gradation value ideally results in output signals having the same potential value for all pixels. However, if the length of the charge retention period differs from row to row, and charges accumulated in the nodes of pixels in each row leak over time, the potential of the pixel output signals differs from row to row, resulting in image data with different gradation levels for each row. Therefore, by using OS transistors as the transistors M15 and M16, the potential change at the pixel nodes can be minimized. In other words, even when imaging using the global shutter system, the change in gradation of image data due to different charge retention periods can be minimized, thereby improving the quality of the captured image.

[0125] On the other hand, it is preferable to use a Si transistor for the transistor M17. A Si transistor can achieve higher field-effect mobility than an OS transistor and has excellent driving capability and current capability. Therefore, the transistor M17 can operate at a higher speed than the transistors M15 and M16. By using a Si transistor for the transistor M17, an output operation in response to a small potential based on the amount of light received by the light-receiving device PD can be quickly performed on the transistor M18.

[0126] That is, in pixel 82, transistors M15 and M16 have low leakage current, and transistor M17 has high driving capability, so that the charge received by the light receiving device PD and transferred via transistor M15 can be held without leakage and can be read out at high speed.

[0127] The transistor M18 functions as a switch that allows the output from the transistor M17 to flow to the wiring WX, and therefore does not necessarily require a small off-state current, high-speed operation, or the like, as the transistors M15 to M17. Therefore, a Si transistor or an OS transistor may be used as the transistor M18.

[0128] Note that although the transistors are depicted as n-channel transistors in FIGS. 5B and 5C, p-channel transistors can also be used.

[0129] The transistors included in the pixel 81 and the pixel 82 are preferably formed side by side on the same substrate.

[0130] <Driving Method Example> An example of a driving method when the configuration of the pixel 81 is applied to the subpixels 81R, 81G, and 81B shown in Fig. 5A will be described with reference to the timing chart shown in Fig. 6A. Fig. 6A shows examples of signals input to the wirings GL, SLR, SLG, and SLB.

[0131] Before time T11, the subpixels 81R, 81G, and 81B are in a non-selected state. Before time T11, a potential (here, a low-level potential) that turns off the transistors M11 and M13 is applied to the wiring GL.

[0132] <Period T11-T12> The period from time T11 to time T12 corresponds to a period for writing data to the pixel. At time T11, a potential (here, a high-level potential) that turns on the transistors M11 and M13 is applied to the wiring GL, and data potentials DR, DG, and DB are applied to the wirings SLR, SLG, and SLB, respectively. At this time, the transistor M11 is turned on, and a data potential is applied to the gate of the transistor M12 from the wiring SLR, SLG, or SLB. Furthermore, the transistor M13 is turned on, and a reset potential is applied to one electrode of the light-emitting device EL from the wiring RL. This prevents the light-emitting device EL from emitting light during the writing period.

[0133] <After Time T12> The period after time T12 corresponds to the write period for the next row. At time T12, a potential is applied to the wiring GL to turn off the transistors M11 and M13, turning off the transistors M11 and M13. This causes a current corresponding to the gate potential of the transistor M12 to flow through the light-emitting device EL, causing the light-emitting device EL to emit light at a desired luminance.

[0134] The above is a description of an example of a method for driving the pixel 81.

[0135] An example of a method for driving the pixel 82 shown in Fig. 5C will be described with reference to the timing chart shown in Fig. 6B, which illustrates signals input to the wirings TX, SE, RS, and WX.

[0136] <Before Time T21> Before time T21, a low-level potential is applied to the wiring TX, the wiring SE, and the wiring RS. The wiring WX is in a state where no data is being output, and is shown here as a low-level potential. A predetermined potential may be applied to the wiring WX.

[0137] <Period T21-T22> At time T21, potentials (here, high-level potentials) that turn on the transistors are applied to the wirings TX and RS, and potentials (here, low-level potentials) that turn off the transistors are applied to the wirings SE.

[0138] At this time, the transistors M15 and M16 are turned on, so that a potential lower than the potential of the cathode is applied to the anode of the light-receiving device PD from the wiring V11 via the transistors M16 and M15. In other words, a reverse bias voltage is applied to the light-receiving device PD.

[0139] The potential of the wiring V11 is also supplied to the first electrode of the capacitor C21, and the capacitor C21 is charged.

[0140] The period T21-T22 can also be called a reset (initialization) period.

[0141] <Period T22 to T23> At time T22, a low-level potential is applied to the wiring TX and the wiring RS, thereby bringing the transistor M15 and the transistor M16 into a non-conductive state.

[0142] Since the transistor M15 is in a non-conductive state, a reverse bias voltage is applied to the light-receiving device PD, and photoelectric conversion occurs due to the light incident on the light-receiving device PD, and electric charges are accumulated in the light-receiving device PD.

[0143] The period T22-T23 can also be called an exposure period. The exposure period may be set depending on the sensitivity of the light receiving device PD, the amount of incident light, etc., but it is preferable to set the exposure period to a period that is at least sufficiently longer than the reset period.

[0144] During the period T22-T23, the transistor M15 and the transistor M16 are turned off, and therefore the potential of the first electrode of the capacitor C21 is held at the potential supplied from the wiring V11.

[0145] <Period T23-T24> At time T23, a high-level potential is applied to the line TX. This causes the transistor M15 to become conductive, and the charge stored in the light-receiving device PD is transferred to the first electrode of the capacitor C21 via the transistor M15. This causes the potential of the node to which the first electrode of the capacitor C21 is connected to rise in accordance with the amount of charge stored in the light-receiving device PD. As a result, a potential corresponding to the amount of exposure of the light-receiving device PD is applied to the gate of the transistor M17.

[0146] <Period T24-T25> At time T24, a low-level potential is applied to the wiring TX. This turns off the transistor M15, and the node to which the gate of the transistor M17 is connected becomes floating. Because the light-receiving device PD is constantly exposed to light, turning off the transistor M15 after the transfer operation in the period T23-T24 is completed can prevent the potential of the node to which the gate of the transistor M17 is connected from changing.

[0147] <Period T25-T26> At time T25, a high-level potential is applied to the wiring SE, which turns on the transistor M18. The period T25-T26 can also be referred to as a read period.

[0148] For example, data can be read by configuring a source follower circuit with the transistor M17 and a transistor included in the circuit unit 75. In this case, the data potential DS output to the wiring WX is determined according to the gate potential of the transistor M17. Specifically, the potential obtained by subtracting the threshold voltage of the transistor M17 from the gate potential of the transistor M17 is output to the wiring WX as the data potential DS, and this potential is read by a read circuit included in the circuit unit 75.

[0149] It is also possible to configure a common source circuit with the transistor M17 and a transistor included in the circuit section 75, and to read data using a read circuit included in the circuit section 75.

[0150] <After Time T26> At time T26, a low-level potential is applied to the wiring SE. This turns off the transistor M18. This completes the readout of data from the pixel 82. After time T26, the readout operation of data from the next row onward is performed sequentially.

[0151] 6B , the exposure period and the readout period can be set separately, so that all pixels 82 provided in the display unit 71 can be exposed simultaneously and then the data can be read out sequentially. This makes it possible to realize so-called global shutter driving. When global shutter driving is performed, it is preferable to use transistors that function as switches in the pixels 82 (particularly the transistors M15 and M16) that are made of oxide semiconductors, which have extremely low leakage current in a non-conducting state.

[0152] The above is a description of an example of a method for driving the pixel 82.

[0153] <Modifications of Pixel Circuit> Hereinafter, examples of the pixel 81 and the pixel 82 that are different from those described above will be described.

[0154] Transistors having a pair of gates overlapping with a semiconductor layer therebetween can be used as the transistors included in the pixel 81 and the pixel 82. Specific examples of an LTPS transistor and an OS transistor having a pair of gates will be described in detail below.

[0155] In a transistor having a pair of gates, when the pair of gates are electrically connected to each other and supplied with the same potential, the on-state current of the transistor is increased and the saturation characteristics are improved. A potential for controlling the threshold voltage of the transistor may be supplied to one of the pair of gates. Supplying a constant potential to one of the pair of gates can improve the stability of the electrical characteristics of the transistor. For example, one gate of the transistor may be electrically connected to a wiring to which a constant potential is supplied, or to its own source or drain.

[0156] 7A is an example in which the transistors M11 and M13 each have a pair of gates. The pair of gates of the transistors M11 and M13 are electrically connected. With this configuration, the period for writing data to the pixel 81 can be shortened.

[0157] 7B is an example in which a transistor having a pair of gates is used for the transistor M12 in addition to the transistors M11 and M13. The pair of gates of the transistor M12 are electrically connected. By using such a transistor for the transistor M12, the saturation characteristics are improved, which makes it easier to control the emission luminance of the light-emitting device EL and improves the display quality.

[0158] 8A is an example in which a pair of gate-connected transistors are used as the transistors M15 and M16. This configuration can reduce the time required for the reset operation and the transfer operation.

[0159] 8B is an example in which, in addition to the configuration illustrated in FIG. 8A, a transistor having a pair of gates connected to each other is used as transistor M18. By using such a configuration, the time required for readout can be shortened.

[0160] 8C is an example in which, in addition to the configuration illustrated in FIG. 8B, a transistor having a pair of gates connected to each other is also used as transistor M17. By using such a configuration, the time required for readout can be further reduced.

[0161] Configuration Example 3 FIG. 9 shows an example of a circuit diagram of a pixel 80 having sub-pixels 81R, 81G, 81B, and 82PS.

[0162] The sub-pixel 81R has a light-emitting device ELR that emits red light. The sub-pixel 81G has a light-emitting device ELG that emits green light. The sub-pixel 81B has a light-emitting device ELB that emits blue light. The sub-pixels 81R, 81G, and 81B have the same configuration except for the light-emitting devices.

[0163] 9 shows a configuration in which the anode of the light receiving device PD, the cathode of the light emitting device ELR, the cathode of the light emitting device ELG, and the cathode of the light emitting device ELB are each electrically connected to the wiring ACL. This configuration reduces the number of wirings required for the pixel 80, allowing the size of the pixel 80 to be reduced, resulting in a high-resolution display device. It is also possible to use a configuration in which the anode of the light receiving device PD, the cathode of the light emitting device ELR, the cathode of the light emitting device ELG, and the cathode of the light emitting device ELB are each connected to different wirings.

[0164] The configurations of the sub-pixels 81R, 81G, 81B, and 82PS are not limited to the configuration shown in FIG.

[0165] 10A shows an example of the configuration of the light-emitting device and the light-receiving device included in the pixel 80. Fig. 10A is a schematic cross-sectional view showing the configurations of the light-emitting device 11R, the light-emitting device 11G, the light-emitting device 11B, and the light-receiving device 12PS.

[0166] Note that Figure 10A shows an example in which the configuration of the light-emitting device 11e shown in Figure 3B is applied to the light-emitting device 11R, the light-emitting device 11G, and the light-emitting device 11B, and the configuration of the light-receiving device 12e shown in Figure 3B is applied to the light-receiving device 12PS.

[0167] The light-emitting device 11R can be applied to the light-emitting device ELR of the sub-pixel 81R, and has a function of emitting red light. The light-emitting device 11R has a layered structure in which an electrode 13a, an EL layer 17R, a layer 21, and an electrode 15 are layered in this order on a substrate 23. The EL layer 17R has a layered structure in which a layer 33a, a layer 35a, a light-emitting layer 41R, and a layer 37a are layered in this order.

[0168] The layer 33a includes a layer containing a substance with high hole-injection properties (hole-injection layer). The layer 35a includes a layer containing a substance with high hole-transport properties (hole-transport layer). The light-emitting layer 41R includes a light-emitting substance that emits red light. The layer 37a includes a layer containing a substance with high electron-transport properties (electron-transport layer). The layer 21 includes a layer containing a substance with high electron-injection properties (electron-injection layer).

[0169] In the light-emitting device 11R, the electrode 13a functions as an anode, and the electrode 15 functions as a cathode. That is, the potential supplied to the electrode 13a is higher than the potential supplied to the electrode 15.

[0170] The light-emitting device 11G can be applied to the light-emitting device ELG of the sub-pixel 81G and has a function of emitting green light. The light-emitting device 11G has a layered structure in which an electrode 13b, an EL layer 17G, a layer 21, and an electrode 15 are layered in this order on a substrate 23. The EL layer 17G has a layered structure in which a layer 33b, a layer 35b, a light-emitting layer 41G, and a layer 37b are layered in this order.

[0171] The layer 33b includes a layer containing a substance with high hole-injection properties (hole-injection layer). The layer 35b includes a layer containing a substance with high hole-transport properties (hole-transport layer). The light-emitting layer 41G includes a light-emitting substance that emits green light. The layer 37b includes a layer containing a substance with high electron-transport properties (electron-transport layer).

[0172] In the light-emitting device 11G, the electrode 13b functions as an anode, and the electrode 15 functions as a cathode. That is, the potential supplied to the electrode 13b is higher than the potential supplied to the electrode 15.

[0173] The light-emitting device 11B can be applied to the light-emitting device ELB of the subpixel 81B and has a function of emitting blue light. The light-emitting device 11B has a layered structure in which an electrode 13c, an EL layer 17B, a layer 21, and an electrode 15 are layered in this order on a substrate 23. The EL layer 17B has a layered structure in which a layer 33c, a layer 35c, a light-emitting layer 41B, and a layer 37c are layered in this order.

[0174] The layer 33c includes a layer containing a substance with high hole-injection properties (hole-injection layer). The layer 35c includes a layer containing a substance with high hole-transport properties (hole-transport layer). The light-emitting layer 41B includes a light-emitting substance that emits blue light. The layer 37c includes a layer containing a substance with high electron-transport properties (electron-transport layer).

[0175] In the light-emitting device 11B, the electrode 13c functions as an anode, and the electrode 15 functions as a cathode. That is, the potential supplied to the electrode 13c is higher than the potential supplied to the electrode 15.

[0176] The light-receiving device 12PS can be applied to the light-receiving device PD of the subpixel 82PS, and has a function of detecting visible light and infrared light. The light-receiving device 12PS has a layered structure in which an electrode 13d, a light-receiving layer 19PS, a layer 21, and an electrode 15 are layered in this order on a substrate 23. The light-receiving layer 19PS has a layered structure in which a layer 37d, an active layer 43, a layer 35d, and a layer 33d are layered in this order.

[0177] The layer 37d includes a layer containing a substance with high electron transport properties (electron transport layer). The active layer 43PS includes a semiconductor. It is particularly preferable that the active layer 43PS includes an organic semiconductor. The layer 35d includes a layer containing a substance with high hole transport properties (hole transport layer). The layer 33d includes a layer containing a substance with high hole injection properties (hole injection layer). In the light-receiving device 12PS, the layer 33d functions as a hole transport layer.

[0178] In the light-receiving device 12PS, the electrode 13d functions as a cathode, and the electrode 15 functions as an anode. That is, the potential supplied to the electrode 13d is higher than the potential supplied to the electrode 15. In the light-receiving device 12PS, a reverse bias is applied between the electrode 13d and the electrode 15.

[0179] The electrodes 13a, 13b, 13c, and 13d are provided on a substrate 23. The electrodes 13a, 13b, 13c, and 13d can be formed, for example, by processing a conductive film formed on the substrate 23 into an island shape. The electrodes 13a, 13b, 13c, and 13d each function as a pixel electrode. The above description of the electrodes 13A and 13B can be referenced for the electrodes 13a, 13b, 13c, and 13d, and therefore a detailed description thereof will be omitted. The electrode 15 functions as a common electrode. The above description of the electrode 15 can be referenced, and therefore a detailed description thereof will be omitted.

[0180] The detailed description of layers 33a, 33b, 33c, and 33d can be referenced to the description of layers 33A and 33B above, and therefore will be omitted. The detailed description of layers 35a, 35b, 35c, and 35d can be referenced to the description of layers 35A and 35B above, and therefore will be omitted. The detailed description of layers 37a, 37b, 37c, and 37d can be referenced to the description of layers 37A and 37B above, and therefore will be omitted. The detailed description of layer 21, which is a common layer, can be referenced to the description above, and therefore will be omitted.

[0181] Figure 10B shows, with arrows, a schematic representation of red (R) light emitted from light-emitting device 11R, green (G) light emitted from light-emitting device 11G, blue (B) light emitted from light-emitting device 11B, and light incident on light-receiving device 12PS.

[0182] FIG. 11A shows an example of a configuration different from the pixel 80 described above. The pixel 80A shown in FIG. 11A has a light-emitting device 11R, a light-emitting device 11G, a light-emitting device 11B, a light-emitting device 11IR, and a light-receiving device 12PS. FIG. 11A is a schematic cross-sectional view showing the configuration of the light-emitting device 11R, the light-emitting device 11G, the light-emitting device 11B, the light-emitting device 11IR, and the light-receiving device 12PS. The pixel 80A differs mainly from the pixel 80 shown in FIG. 10A etc. in that it has a light-emitting device 11IR.

[0183] The light-emitting device 11IR has a function of emitting infrared light. The light-emitting device 11IR has a layered structure in which an electrode 13e, an EL layer 17IR, a layer 21, and an electrode 15 are layered in this order on a substrate 23. The EL layer 17IR has a layered structure in which a layer 33e, a layer 35e, a light-emitting layer 41IR, and a layer 37e are layered in this order.

[0184] The layer 33e includes a layer containing a substance with high hole-injection properties (hole-injection layer). The layer 35e includes a layer containing a substance with high hole-transport properties (hole-transport layer). The light-emitting layer 41IR includes a light-emitting substance that emits light in the infrared wavelength region. The layer 37e includes a layer containing a substance with high electron-transport properties (electron-transport layer).

[0185] In the light-emitting device 11IR, the electrode 13e functions as an anode, and the electrode 15 functions as a cathode. That is, the potential supplied to the electrode 13e is higher than the potential supplied to the electrode 15.

[0186] The electrode 13e is provided on the substrate 23. The electrode 13e can be formed in the same process as the electrodes 13a, 13b, 13c, and 13d. The electrode 13e functions as a pixel electrode. The description of the electrodes 13A and 13B can be referred to for the electrode 13e, and therefore a detailed description thereof will be omitted.

[0187] The detailed description of layer 33e can be found in the descriptions of layers 33A and 33B, and therefore will be omitted. The detailed description of layer 35e can be found in the descriptions of layers 35A and 35B, and therefore will be omitted. The detailed description of layer 37e can be found in the descriptions of layers 37A and 37B, and therefore will be omitted.

[0188] Figure 11B shows, with arrows, a schematic representation of red (R) light emitted from light-emitting device 11R, green (G) light emitted from light-emitting device 11G, blue (B) light emitted from light-emitting device 11B, infrared (IR) light emitted from light-emitting device 11IR, and light incident on light-receiving device 12PS.

[0189] An example of a configuration different from the pixel 80 described above is shown in Figure 12A. The pixel 80B shown in Figure 12A has a light-emitting device 11R, a light-emitting device 11G, a light-emitting device 11B, a light-receiving device 12PS, and a light-receiving device 12IRS. Figure 12A is a schematic cross-sectional view showing the configuration of the light-emitting device 11R, the light-emitting device 11G, the light-emitting device 11B, the light-receiving device 12PS, and the light-receiving device 12IRS. The pixel 80B differs mainly from the pixel 80 shown in Figure 10A etc. in the configuration of the light-receiving device.

[0190] The light receiving device 12PS of the pixel 80 has a function of receiving visible light, and the light receiving device 12IRS has a function of receiving infrared light.

[0191] The light-receiving device 12IRS has a layered structure in which an electrode 13f, a light-receiving layer 19IRS, a layer 21, and an electrode 15 are layered in this order on a substrate 23. The light-receiving layer 19IRS has a layered structure in which a layer 37f, an active layer 43IRS, a layer 35f, and a layer 33f are layered in this order.

[0192] The layer 37f includes a layer containing a substance with high electron transport properties (electron transport layer). The active layer 43IRS includes a semiconductor. It is particularly preferable that the active layer 43IRS includes an organic semiconductor. The layer 35f includes a layer containing a substance with high hole transport properties (hole transport layer). The layer 33f includes a layer containing a substance with high hole injection properties (hole injection layer). In the light-receiving device 12IRS, the layer 33f functions as a hole transport layer.

[0193] In the light receiving device 12IRS, the electrode 13f functions as a cathode, and the electrode 15 functions as an anode. That is, the potential supplied to the electrode 13f is higher than the potential supplied to the electrode 15.

[0194] The electrode 13f is provided on the substrate 23. The electrode 13f can be formed in the same process as the electrodes 13a, 13b, 13c, 13d, and 13e. The electrode 13e functions as a pixel electrode. The description of the electrodes 13A and 13B above can be referred to for the electrode 13f, and therefore a detailed description thereof will be omitted.

[0195] The detailed description of layer 33f can be referenced to the descriptions of layers 33A and 33B, and therefore will be omitted. The detailed description of layer 35f can be referenced to the descriptions of layers 35A and 35B, and therefore will be omitted. The detailed description of layer 37f can be referenced to the descriptions of layers 37A and 37B, and therefore will be omitted.

[0196] Figure 12B shows, with arrows, a schematic representation of red (R) light emitted from light-emitting device 11R, green (G) light emitted from light-emitting device 11G, blue (B) light emitted from light-emitting device 11B, light incident on light-receiving device 12PS, and light incident on light-receiving device 12IRS.

[0197] An example of a configuration different from the pixel 80B described above is shown in Figure 13A. The pixel 80B shown in Figure 13A has a light-emitting device 11R, a light-emitting device 11G, a light-emitting device 11B, a light-emitting device 11IR, a light-receiving device 12PS, and a light-receiving device 12IRS. Figure 13A is a schematic cross-sectional view showing the configuration of the light-emitting device 11R, the light-emitting device 11G, the light-emitting device 11B, the light-emitting device 11IR, the light-receiving device 12PS, and the light-receiving device 12IRS. The pixel 80C differs mainly from the pixel 80B shown in Figure 12A etc. in that it has a light-emitting device 11IR.

[0198] Figure 13B shows, with arrows, a schematic representation of red (R) light emitted from light-emitting device 11R, green (G) light emitted from light-emitting device 11G, blue (B) light emitted from light-emitting device 11B, infrared (IR) light emitted from light-emitting device 11IR, light incident on light-receiving device 12PS, and light incident on light-receiving device 12IRS.

[0199] 14A is a schematic diagram of a display device of one embodiment of the present invention. A display device 200 shown in FIG. 14A includes a substrate 201, a substrate 202, a light-emitting device 211R, a light-emitting device 211G, a light-emitting device 211B, a light-receiving device 212PS, a functional layer 203, and the like.

[0200] The light-emitting device 211R, the light-emitting device 211G, the light-emitting device 211B, and the light-receiving device 212PS are provided between the substrate 201 and the substrate 202. The light-emitting device 211R, the light-emitting device 211G, and the light-emitting device 211B emit red (R), green (G), or blue (B) light, respectively. The light-emitting device 211R, the light-emitting device 211G, and the light-emitting device 211B may be the light-emitting device described above. The light-receiving device 212PS may be the light-receiving device described above. Note that, hereinafter, when there is no need to particularly distinguish between the light-emitting device 211R, the light-emitting device 211G, and the light-emitting device 211B, they may be referred to as the light-emitting device 211.

[0201] 14A shows a state in which finger 220 touches the surface of substrate 202. A portion of light emitted by a light-emitting device (e.g., light-emitting device 211G) is reflected at the contact point between substrate 202 and finger 220. A portion of the reflected light is then incident on light-receiving device 212PS, making it possible to detect that finger 220 has touched substrate 202. In other words, display device 200 can function as a touch panel.

[0202] The functional layer 203 has circuits for driving the light-emitting devices 211R, 211G, and 211B, and a circuit for driving the light-receiving device 212PS. The functional layer 203 is provided with switches, transistors, capacitors, wiring, and the like. Note that, when the light-emitting devices 211R, 211G, and 211B, and the light-receiving device 212PS are driven by a passive matrix method, a configuration without switches and transistors may be used.

[0203] The display device 200 can detect, for example, the fingerprint of a finger 220. Fig. 14B is a schematic enlarged view of a contact portion between the substrate 202 and the finger 220. Fig. 14B also shows light-emitting devices 211 and light-receiving devices 212 arranged alternately.

[0204] A fingerprint is formed on the finger 220 by recesses and protrusions, and therefore the protrusions of the fingerprint are in contact with the substrate 202 as shown in FIG.

[0205] Light reflected from a surface or interface can be classified as specular reflection or diffuse reflection. Specular reflection is highly directional light, with the angle of incidence and the angle of reflection matching, while diffuse reflection is low-directional light, with its intensity less dependent on the angle. The diffuse reflection component is dominant in the light reflected from the surface of the finger 220. On the other hand, the specular reflection component is dominant in the light reflected from the interface between the substrate 202 and the atmosphere.

[0206] The intensity of light reflected by the contact or non-contact surface between the finger 220 and the substrate 202 and incident on the light receiving device 212 located directly below them is the sum of specularly reflected light and diffusely reflected light. As described above, at the concave portions of the finger 220, the substrate 202 and the finger 220 do not come into contact, so specularly reflected light (indicated by the solid arrows) is dominant, whereas at the convex portions, they come into contact, so diffusely reflected light (indicated by the dashed arrows) from the finger 220 is dominant. Therefore, the intensity of light received by the light receiving device 212 located directly below the concave portions is higher than that of the light receiving device 212 located directly below the convex portions. This makes it possible to capture an image of the fingerprint of the finger 220.

[0207] A clear fingerprint image can be obtained by arranging the light receiving devices 212 at an interval smaller than the distance between two convex portions of a fingerprint, preferably the distance between adjacent convex and concave portions. Since the distance between convex and concave portions of a human fingerprint is approximately 200 μm, the interval between the light receiving devices 212 is, for example, 400 μm or less, preferably 200 μm or less, more preferably 150 μm or less, even more preferably 100 μm or less, and even more preferably 50 μm or less, and is 1 μm or more, preferably 10 μm or more, and more preferably 20 μm or more.

[0208] 14C shows an example of a fingerprint image captured by display device 200. In Fig. 14C, the outline of finger 220 is indicated by a dashed line and the outline of contact portion 224 is indicated by a dashed line within imaging range 227. Within contact portion 224, a fingerprint 222 with high contrast can be captured due to differences in the amount of light incident on light receiving device 212.

[0209] The display device 200 can also function as a touch panel or a pen tablet. Fig. 14D shows a state in which the tip of a stylus 229 is in contact with the substrate 202 and is slid in the direction of the dashed arrow.

[0210] As shown in Figure 14D, the diffuse reflected light scattered by the tip of the stylus 229 and the contact surface of the substrate 202 is incident on the light receiving device 212 located at the part overlapping with the contact surface, thereby enabling the position of the tip of the stylus 229 to be detected with high accuracy.

[0211] 14E shows an example of a trajectory 226 of the stylus 229 detected by the display device 200. The display device 200 is capable of detecting the position of a detectable object such as the stylus 229 with high positional accuracy, and therefore is also capable of performing high-resolution drawing in drawing applications, etc. Furthermore, unlike when a capacitive touch sensor, an electromagnetic induction touch pen, or the like is used, the position of even a highly insulating detectable object can be detected, and therefore the material of the tip of the stylus 229 is not a factor, and various writing implements (e.g., a brush, a glass pen, a feather pen) can be used.

[0212] The light receiving device 212PS can be used as a touch sensor (also called a direct touch sensor) or a near-touch sensor (also called a hover sensor, hover touch sensor, non-contact sensor, or touchless sensor). FIG. 15 shows how light 31 emitted from a light emitting device (e.g., light emitting device 211G) is reflected by an object (e.g., finger 220), and the reflected light 32 is incident on the light receiving device 212PS. Although the object is not in contact with the display device 200, the object can be detected using the light receiving device 212PS. Note that the wavelength of light to be detected by the light receiving device 212PS may be appropriately determined depending on the application.

[0213] A touch sensor or near-touch sensor can detect the proximity or contact of an object (such as a finger, hand, or pen). A touch sensor can detect an object by direct contact between the display device and the object. A near-touch sensor can detect an object even if the object does not touch the display device. For example, a configuration in which the display device can detect an object when the distance between the display device and the object is 0.1 mm or more and 300 mm or less, preferably 3 mm or more and 50 mm or less, is preferred. This configuration enables the display device to be operated without the object directly touching it, in other words, to be operated in a non-contact (touchless) manner. This configuration reduces the risk of the display device becoming dirty or scratched, or enables the display device to be operated without the object directly touching dirt (e.g., dust or viruses) attached to the display device.

[0214] The display device of one embodiment of the present invention can have a variable refresh rate. For example, the refresh rate can be adjusted (for example, adjusted within a range of 1 Hz to 240 Hz) depending on content displayed on the display device, thereby reducing power consumption. Furthermore, the drive frequency of the touch sensor or near-touch sensor may be changed depending on the refresh rate. For example, when the refresh rate of the display device is 120 Hz, the drive frequency of the touch sensor or near-touch sensor can be configured to be higher than 120 Hz (typically 240 Hz). This configuration enables low power consumption and an increased response speed of the touch sensor or near-touch sensor.

[0215] It is preferable that the light receiving device 212PS is provided in all pixels of the display device. By providing the light receiving device 212PS in all pixels, touch detection can be performed with high accuracy. Note that the light receiving device 212PS may be provided in some pixels. For example, the display device may have pixels provided with both a light emitting device and a light receiving device, and pixels provided with a light receiving device (without a light emitting device only).

[0216] 16A shows an example of a configuration different from the above-described display device 200. The display device 200A shown in Fig. 16A includes a substrate 201, a substrate 202, a light-emitting device 211R, a light-emitting device 211G, a light-emitting device 211B, a light-emitting device 211IR, a light-receiving device 212PS, and a functional layer 203. The display device 200A differs from the above-described display device 200 mainly in that the display device 200A includes a light-emitting device 211IR.

[0217] The light-emitting device 211R, the light-emitting device 211G, the light-emitting device 211B, and the light-receiving device 212PS are provided between the substrate 201 and the substrate 202. The light-emitting device 211IR emits infrared light. The light-emitting device described above can be used as the light-emitting device 211IR.

[0218] 16A shows a state in which finger 220 touches the surface of substrate 202. A portion of light emitted from a light-emitting device (e.g., light-emitting device 211IR) is reflected at the contact point between substrate 202 and finger 220. A portion of the reflected light is then incident on light-receiving device 212PS, making it possible to detect that finger 220 has touched substrate 202. For example, by emitting infrared light from light-emitting device 211IR and detecting the infrared light with light-receiving device 212PS, touch detection becomes possible even in a dark place.

[0219] The display device 200A can display an image on the display unit using the light-emitting device 211R, the light-emitting device 211G, and the light-emitting device 211B, and can perform touch detection on the display unit using the light-emitting device 211IR and the light-receiving device 212PS. The display device 200A can also display an image on the display unit and can capture an image on the display unit.

[0220] 16B shows how light 31 emitted from light-emitting device 211G is reflected by an object (e.g., finger 220) and the reflected light 32 is incident on light-receiving device 212PS. FIG. 16C shows how light 31 emitted from light-emitting device 211IR is reflected by an object (e.g., finger 220) and the reflected light 32 is incident on light-receiving device 212PS. Although the object is not in contact with display device 200A, the object can be detected using light-receiving device 212PS.

[0221] 17A shows an example of a configuration different from the display device 200A described above. The display device 200B shown in Fig. 17A includes a substrate 201, a substrate 202, a light-emitting device 211R, a light-emitting device 211G, a light-emitting device 211B, a light-emitting device 211IR, a light-receiving device 212PS, a light-receiving device 212IRS, and a functional layer 203. The display device 200B differs from the display device 200A described above mainly in the configuration of the light-receiving device.

[0222] The light-emitting device 211R, the light-emitting device 211G, the light-emitting device 211B, the light-receiving device 212PS, and the light-receiving device 212IRS are provided between the substrate 201 and the substrate 202. The light-receiving device 212PS receives visible light. The light-receiving device 212IRS receives infrared light. The light-receiving device 212PS and the light-receiving device 212IRS can be the light-receiving devices described above.

[0223] 17A shows a state in which a finger 220 touches the surface of the substrate 202. A portion of the light emitted by a light-emitting device (e.g., light-emitting device 211IR) is reflected at the contact point between the substrate 202 and the finger 220. Then, a portion of the reflected light is incident on the light-receiving device 212IRS, thereby making it possible to detect that the finger 220 has touched the substrate 202.

[0224] 17B shows how light 31 emitted from light-emitting device 211IR is reflected by an object (e.g., finger 220) and the reflected light 32 is incident on light-receiving device 212IRS. FIG. 17C shows how light 31 emitted from light-emitting device 211G is reflected by an object (e.g., finger 220) and the reflected light 32 is incident on light-receiving device 212PS. Although the object is not in contact with display device 200B, the object can be detected using light-receiving device 212PS or light-receiving device 212IRS.

[0225] The area of ​​the light receiving region of the light receiving device 212PS (hereinafter also referred to as the light receiving area) is preferably smaller than the light receiving area of ​​the light receiving device 212IRS. By reducing the light receiving area of ​​the light receiving device 212PS, i.e., narrowing the imaging range, the light receiving device 212PS can capture images with higher resolution than the light receiving device 212IRS. In this case, the light receiving device 212PS can be used for imaging for personal authentication using fingerprints, palm prints, irises, pulse shapes (including vein shapes and arterial shapes), faces, etc. Note that the wavelength of light detected by the light receiving device 212PS may be appropriately determined depending on the application.

[0226] A method for detecting an object may be selected depending on the function, based on the difference in detection accuracy between the light receiving device 212PS and the light receiving device 212IRS. For example, the scrolling function of the display screen may be realized by a near-touch sensor function using the light receiving device 212IRS, and the input function using a keyboard displayed on the screen may be realized by a high-definition touch sensor function using the light receiving device 212PS.

[0227] By mounting two types of light receiving devices in one pixel, two additional functions can be added in addition to the display function, making it possible to provide a multi-function display device.

[0228] In order to capture high-resolution images, it is preferable that the light receiving devices 212PS are provided in all pixels of the display device. On the other hand, the light receiving devices 212IRS used in touch sensors or near-touch sensors do not require as high accuracy as detection using the light receiving devices 212PS, so they may be provided in only some of the pixels of the display device. By reducing the number of light receiving devices 212IRS provided in the display device compared to the number of light receiving devices 212PS, the detection speed can be increased.

[0229] As described above, the display device of this embodiment can be a multi-functional display device by incorporating a light-emitting device and a light-receiving device in one pixel. For example, a display device having a high-resolution imaging function and a sensing function such as a touch sensor or a near-touch sensor can be realized.

[0230] A display device according to one embodiment of the present invention may emit light of a specific color and receive light reflected by an object. Fig. 18A shows red light emitted from the display device and red light reflected by an object (here, finger 220) and incident on the display device, each indicated by an arrow. Fig. 18B shows infrared light emitted from the display device and infrared light reflected by the object (here, finger 220) and incident on the display device, each indicated by an arrow.

[0231] The transmittance of the object to red light can be measured by emitting red light while the object is in contact with or close to the display device and allowing the reflected light from the object to enter the display device. Similarly, the transmittance of the object to infrared light can be measured by emitting infrared light while the object is in contact with or close to the display device and allowing the reflected light from the object to enter the display device.

[0232] 18C is an enlarged view of region P indicated by the dashed line in FIG. 18A. Light 31 emitted from light-emitting device 211R is scattered by biological tissue on the surface and inside finger 220, and some of the scattered light travels from inside the body toward light-receiving device 212PS. This scattered light passes through blood vessel 91, and transmitted light 32 enters light-receiving device 212PS.

[0233] Similarly, the infrared light emitted from the light-emitting device 211IR is scattered by the surface and internal biological tissue of the finger 220, and some of the scattered infrared light travels from inside the biological tissue toward the light-receiving device 212IRS. This scattered infrared light passes through the blood vessel 91, and the transmitted infrared light enters the light-receiving device 212IRS.

[0234] Here, light 32 is light that has passed through biological tissue 93 and blood vessels 91 (arteries and veins). Because arterial blood pulsates with the heartbeat, light absorption by the arteries varies depending on the heartbeat. On the other hand, because biological tissue 93 and veins are not affected by the heartbeat, light absorption by the biological tissue 93 and the veins is constant. Therefore, the light transmittance of the arteries can be calculated by removing components that remain constant over time from the light 32 incident on the display device. Furthermore, the transmittance of red light is lower for hemoglobin that is not bound to oxygen (also called deoxygenated hemoglobin) than for hemoglobin that is bound to oxygen (also called oxygenated hemoglobin). The transmittance of infrared light is similar for oxygenated hemoglobin and deoxygenated hemoglobin. By measuring the transmittance of arteries to red light and infrared light, the ratio of oxygenated hemoglobin to the sum of oxygenated hemoglobin and deoxygenated hemoglobin, that is, oxygen saturation (hereinafter referred to as transcutaneous oxygen saturation (SpO ２ In this manner, the display device which is one embodiment of the present invention can function as a reflective pulse oximeter.

[0235] For example, when a finger touches a display unit of a display device, position information of the area touched by the finger is acquired. Then, red light is emitted from pixels in the area touched by the finger and in the vicinity thereof, and the transmittance of the artery for the red light is measured. Next, infrared light is emitted and the transmittance of the artery for the infrared light is measured, thereby calculating oxygen saturation. The order in which the transmittance for red light and the transmittance for infrared light are measured is not particularly limited. The transmittance for infrared light may be measured first, and then the transmittance for red light. While an example of calculating oxygen saturation using a finger has been described here, one embodiment of the present invention is not limited thereto. Oxygen saturation can also be calculated using a site other than a finger. For example, oxygen saturation can be calculated by measuring the transmittance for red light and the transmittance for infrared light while the palm is in contact with the display unit of a display device.

[0236] 19A illustrates an example of an electronic device to which the display device of one embodiment of the present invention is applied. A portable information terminal 400 illustrated in FIG. 19A can be used as, for example, a smartphone. The portable information terminal 400 includes a housing 402 and a display portion 404. The display device described above can be applied to the display portion 404. For example, the display device 200B described above can be suitably used for the display portion 404.

[0237] Fig. 19A shows a state in which a finger 406 is in contact with a display unit 404 of a mobile information terminal 400. In Fig. 19A, the area where the touch is detected and an area 408 nearby are indicated by a two-dot chain line.

[0238] The mobile information terminal 400 emits red light from the pixels in region 408 and detects the red light incident on the display unit 404. Similarly, the oxygen saturation of the finger 406 can be measured by emitting infrared light from the pixels in region 408 and detecting the infrared light incident on the display unit 404. FIG. 19B shows the pixels in region 408 being lit. In FIG. 19B, the finger 406 is shown as a transparent element, with only the outline indicated by a dashed line, and the region 408 hatched. As shown in FIG. 19B, the lit region 408 is hidden by the finger 406 and is difficult for the user to see. This allows oxygen saturation to be measured without causing stress to the user. Furthermore, the mobile information terminal 400 can measure oxygen saturation at any position within the display unit 404.

[0239] The obtained oxygen saturation level may be displayed on the display unit 404. FIG. 19C shows an example of the image 409, which shows the oxygen saturation level, displayed in the area 407. In FIG. 19C, an image 409, which shows the oxygen saturation level, is displayed. ２ The image 409 may be an image or may include an image and text. The area 407 may be provided at any position on the display unit 404.

[0240] This embodiment mode can be combined with other embodiment modes as appropriate. In addition, in this specification, when a plurality of configuration examples are shown in one embodiment mode, the configuration examples can be combined as appropriate.

[0241] Embodiment 2 In this embodiment, a display device according to one embodiment of the present invention and a manufacturing method thereof will be described with reference to FIGS.

[0242] When manufacturing a display device having light-emitting devices and light-receiving devices that emit light of different colors, it is necessary to form a plurality of light-emitting layers and active layers in the shape of islands.

[0243] For example, island-shaped light-emitting layers and active layers can be formed by vacuum deposition using a metal mask (also called a shadow mask). However, with this method, deviations from the design occur in the shape and position of the island-shaped light-emitting layers and active layers due to various factors, such as the accuracy of the metal mask, misalignment between the metal mask and the substrate, deflection of the metal mask, and the spread of the contours of the formed film due to vapor scattering, making it difficult to achieve high-definition displays and high aperture ratios.

[0244] In a manufacturing method of a display device according to one embodiment of the present invention, an island-shaped pixel electrode (which can also be referred to as a lower electrode) is formed, a first layer to be an EL layer is formed over the entire surface, and then a first sacrificial layer is formed on the first layer. Then, a first resist mask is formed on the first sacrificial layer, and the first layer and the first sacrificial layer are processed using the first resist mask to form the island-shaped EL layer. Similarly, a second layer to be an emission layer is formed using a second sacrificial layer and a second resist mask. Note that in this specification and the like, the sacrificial layer may also be referred to as a mask layer.

[0245] As described above, in the manufacturing method of a display device according to one embodiment of the present invention, the island-shaped EL layer is not formed using a fine metal mask (high-resolution metal mask) but is formed by depositing a layer to become the EL layer on the entire surface and then processing it. Similarly, the island-shaped light-receiving layer is not formed using a fine metal mask but is formed by depositing a layer to become the light-receiving layer on the entire surface and then processing it. Therefore, a high-resolution display device or a display device with a high aperture ratio, which has been difficult to achieve until now, can be realized. Furthermore, since the EL layer can be formed separately for each color, a display device with extremely vivid images, high contrast, and high display quality can be realized. Furthermore, a light-receiving device can be provided in each pixel, thereby realizing a display device having a high-resolution imaging function and a sensing function such as a touch sensor or near-touch sensor. Furthermore, by providing a sacrificial layer on the EL layer and the light-receiving layer, damage to the EL layer and the light-receiving layer during the manufacturing process of the display device can be reduced, thereby improving the reliability of the light-emitting device and the light-receiving device.

[0246] For example, it is difficult to achieve a spacing of less than 10 μm between adjacent light-emitting devices and light-receiving devices using a fine metal mask. However, the above method can narrow the spacing to 3 μm or less, 2 μm or less, or even 1 μm or less. Furthermore, for example, by using an exposure device for LSIs, the spacing can be narrowed to 500 nm or less, 200 nm or less, 100 nm or less, or even 50 nm or less. This allows the area of ​​the light-emitting region (hereinafter also referred to as the light-emitting area) and the light-receiving area in the pixel to be increased, enabling the aperture ratio to approach 100%. For example, the aperture ratio can be 50% or more, 60% or more, 70% or more, 80% or more, or even 90% or more, but less than 100%.

[0247] The patterns of the EL layer and the light-receiving layer themselves can also be made much smaller than when a fine metal mask is used. For example, when a fine metal mask is used to separately form the EL layer and the light-receiving layer, thickness variations occur between the center and edges of the EL layer, resulting in a smaller effective area that can be used as the light-emitting region or the light-receiving region relative to the area of ​​the EL layer. On the other hand, with the above-described manufacturing method, a pattern is formed by processing a film formed to a uniform thickness, so the thickness can be made uniform within the pattern, and even with a fine pattern, almost the entire area can be used as the light-emitting region or the light-receiving region. This makes it possible to manufacture a display device that combines high definition and a high aperture ratio.

[0248] <Structure Example 1 of Display Device> FIGS. 20A and 20B illustrate a display device of one embodiment of the present invention.

[0249] 20A is a top view of the display device 100. The display device 100 has a display section in which a plurality of pixels 110 are arranged in a matrix, and a connection section 140 on the outside of the display section. The connection section 140 can be referred to as a cathode contact section.

[0250] A stripe arrangement is applied to the pixel 110 shown in FIG. 20A . The pixel 110 shown in FIG. 20A is composed of four subpixels: subpixel 110a, subpixel 110b, subpixel 110c, and subpixel 110d. The subpixels 110a, 110b, and 110c each have a light-emitting device that emits light in a different wavelength region. The light-emitting devices described above can be used as the light-emitting devices. The subpixels 110a, 110b, and 110c can be three-color subpixels of red (R), green (G), and blue (B), or three-color subpixels of yellow (Y), cyan (C), and magenta (M). The subpixel 110d has a light-receiving device. The light-receiving device can be the light-receiving device described above.

[0251] 20A shows an example in which the sub-pixels are arranged side by side in the X direction, and sub-pixels of the same type are arranged side by side in the Y direction. Note that different types of sub-pixels may be arranged side by side in the Y direction, and sub-pixels of the same type may be arranged side by side in the X direction.

[0252] 20A shows an example in which the connection portion 140 is located below the display portion when viewed from above, but this is not particularly limited. The connection portion 140 may be provided in at least one location on the upper, right, left, or lower side of the display portion when viewed from above, and may be provided so as to surround all four sides of the display portion. Furthermore, the number of connection portions 140 may be one or more.

[0253] A cross-sectional view taken along the dashed dotted line X1-X2 in FIG. 20A is shown in FIG. 20B.

[0254] 20B , display device 100 includes light-emitting device 130a, light-emitting device 130b, light-emitting device 130c, and light-receiving device 130d provided on transistor-containing layer 101. Furthermore, protective layer 131 and protective layer 132 are provided to cover these light-emitting devices and light-receiving devices. Substrate 120 is bonded to protective layer 132 with resin layer 122. Furthermore, insulating layer 125 and insulating layer 127 on insulating layer 125 are provided in the regions between adjacent light-emitting devices and light-receiving devices.

[0255] The display device of one embodiment of the present invention may be any of a top emission type that emits light in a direction opposite to a substrate on which a light-emitting device is formed, a bottom emission type that emits light toward a substrate on which a light-emitting device is formed, and a dual emission type that emits light from both sides.

[0256] The transistor-containing layer 101 may have a laminated structure in which, for example, a plurality of transistors are provided on a substrate and an insulating layer is provided to cover these transistors. The transistor-containing layer 101 may have a recess between adjacent light-emitting devices. For example, a recess may be provided in an insulating layer located on the outermost surface of the transistor-containing layer 101.

[0257] The light emitting devices 130a, 130b, and 130c each emit light in a different wavelength region, and preferably emit light of three colors, for example, red (R), green (G), and blue (B).

[0258] The light-emitting device 130 a has a pixel electrode 111 a on a layer 101 including a transistor, an island-shaped EL layer 113 a on the pixel electrode 111 a, a layer 114 on the island-shaped EL layer 113 a, and a common electrode 115 on the layer 114.

[0259] The light-emitting device 130b has a pixel electrode 111b on the layer 101 including the transistor, an island-shaped EL layer 113b on the pixel electrode 111b, a layer 114 on the island-shaped EL layer 113b, and a common electrode 115 on the layer 114.

[0260] The light-emitting device 130c has a pixel electrode 111c on the layer 101 including the transistor, an island-shaped EL layer 113c on the pixel electrode 111c, a layer 114 on the island-shaped EL layer 113c, and a common electrode 115 on the layer 114.

[0261] The light receiving device 130d has a pixel electrode 111d on the layer 101 including the transistor, an island-shaped light receiving layer 113d on the pixel electrode 111d, a layer 114 on the island-shaped light receiving layer 113d, and a common electrode 115 on the layer 114.

[0262] The light-emitting devices and light-receiving devices of each color share the same film as a common electrode. The common electrode is electrically connected to a conductive layer provided in the connection portion 140. As a result, the same potential is supplied to the common electrodes of the light-emitting devices and light-receiving devices of each color.

[0263] The pair of electrodes (pixel electrode and common electrode) of the light-emitting device and the light-receiving device can be appropriately made of a metal, an alloy, an electrically conductive compound, a mixture thereof, etc. Specific examples include indium tin oxide (In-Sn oxide, also referred to as ITO), In-Si-Sn oxide (also referred to as ITSO), indium zinc oxide (In-Zn oxide), In-W-Zn oxide, an alloy containing aluminum (aluminum alloy) such as an alloy of aluminum, nickel, and lanthanum (Al-Ni-La), and an alloy containing silver such as an alloy of silver and magnesium and an alloy of silver, palladium, and copper (Ag-Pd-Cu, also referred to as APC). Other examples of the metals that can be used include aluminum (Al), magnesium (Mg), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), and neodymium (Nd), as well as alloys containing appropriate combinations of these metals. Other examples of the metals that can be used include elements belonging to Group 1 or Group 2 of the periodic table (e.g., lithium (Li), cesium (Cs), calcium (Ca), and strontium (Sr)), rare earth metals such as europium (Eu), and ytterbium (Yb), as well as alloys containing appropriate combinations of these metals, graphene, and the like.

[0264] The light-emitting device preferably has a micro-optical resonator (microcavity) structure. Therefore, one of a pair of electrodes of the light-emitting device preferably has a transmissive and reflective electrode for visible light, and the other preferably has a reflective electrode for visible light. By having the light-emitting device have a microcavity structure, the light emitted from the light-emitting layer can be resonated between the two electrodes, thereby intensifying the light emitted from the light-emitting device.

[0265] The semi-transmitting / semi-reflective electrode can have a stacked structure of an electrode that is reflective to visible light and an electrode that is transparent to visible light (also referred to as a transparent electrode).

[0266] The light transmittance of the transparent electrode is 40% or more. For example, it is preferable to use an electrode with a visible light transmittance of 40% or more for a light emitting element. The visible light reflectance of the semi-transmissive / semi-reflective electrode is 10% to 95%, preferably 30% to 80%. The visible light reflectance of the reflective electrode is 40% to 100%, preferably 70% to 100%. Furthermore, the resistivity of these electrodes is 1×10 −２ When the light emitting element emits infrared light, the transmittance or reflectance of these electrodes for infrared light preferably satisfies the above-mentioned numerical range, similar to the transmittance or reflectance for visible light.

[0267] The EL layer 113a, the EL layer 113b, the EL layer 113c, and the light-receiving layer 113d are each provided in an island shape. The EL layer 113a, the EL layer 113b, and the EL layer 113c each have a light-emitting layer. It is preferable that the EL layer 113a, the EL layer 113b, and the EL layer 113c each have a light-emitting layer that emits light in a different wavelength region. The light-receiving layer 113d has an active layer.

[0268] The light-emitting layer is a layer containing a light-emitting substance. The light-emitting layer can contain one or more light-emitting substances. As the light-emitting substance, a substance that emits light of a color such as blue, purple, blue-purple, green, yellow-green, yellow, orange, or red is appropriately used. Furthermore, as the light-emitting substance, a substance that emits infrared light can also be used.

[0269] Examples of the light-emitting material include fluorescent materials, phosphorescent materials, TADF materials, and quantum dot materials.

[0270] Examples of fluorescent materials include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives.

[0271] Examples of phosphorescent materials include organometallic complexes (particularly iridium complexes) having a 4H-triazole skeleton, a 1H-triazole skeleton, an imidazole skeleton, a pyrimidine skeleton, a pyrazine skeleton, or a pyridine skeleton; organometallic complexes (particularly iridium complexes) having a phenylpyridine derivative having an electron-withdrawing group as a ligand; platinum complexes; and rare earth metal complexes.

[0272] The light-emitting layer may contain one or more organic compounds (host materials, assist materials, etc.) in addition to a light-emitting substance (guest material). One or both of a hole-transporting material and an electron-transporting material may be used as the one or more organic compounds. Furthermore, a bipolar material or a TADF material may be used as the one or more organic compounds.

[0273] The light-emitting layer preferably includes, for example, a phosphorescent material and a hole-transporting material and an electron-transporting material that are a combination that easily forms an exciplex. This configuration allows for efficient emission using Exciplex-Triple Energy Transfer (ExTET), which is energy transfer from the exciplex to the light-emitting material (phosphorescent material). By selecting a combination that forms an exciplex that emits light that overlaps with the wavelength of the lowest-energy absorption band of the light-emitting material, energy transfer becomes smooth, allowing for efficient emission. This configuration simultaneously enables high efficiency, low-voltage operation, and long life of the light-emitting device.

[0274] As a combination of materials that form an exciplex, it is preferable that the HOMO level (highest occupied molecular orbital level) of the hole transporting material is equal to or higher than the HOMO level of the electron transporting material. It is also preferable that the LUMO level (lowest unoccupied molecular orbital level) of the hole transporting material is equal to or higher than the LUMO level of the electron transporting material. The LUMO level and HOMO level of the material can be derived from the electrochemical properties (reduction potential and oxidation potential) of the material measured by cyclic voltammetry (CV).

[0275] The formation of exciplexes can be confirmed, for example, by comparing the emission spectra of the hole-transporting material, the electron-transporting material, and a mixed film obtained by mixing these materials, and observing the phenomenon in which the emission spectrum of the mixed film is shifted to longer wavelengths than the emission spectra of each material (or has a new peak on the longer wavelength side). Alternatively, it can be confirmed by comparing the transient photoluminescence (PL) of the hole-transporting material, the transient PL of the electron-transporting material, and a mixed film obtained by mixing these materials, and observing differences in transient response, such as the transient PL lifetime of the mixed film having a longer-lifetime component or a larger proportion of delayed components than the transient PL lifetimes of the individual materials. The above-mentioned transient PL may also be interpreted as transient electroluminescence (EL). That is, the formation of exciplexes can also be confirmed by comparing the transient EL of the hole-transporting material, the transient EL of the electron-transporting material, and a mixed film obtained by mixing these materials, and observing the differences in transient response.

[0276] The EL layer 113 a, the EL layer 113 b, and the EL layer 113 c may further include, as a layer other than the light-emitting layer, a layer containing a substance with a high hole-injection property, a substance with a high hole-transport property (also referred to as a hole-transport material), a hole-blocking material, a substance with a high electron-transport property (also referred to as an electron-transport material), a substance with a high electron-injection property, an electron-blocking material, a bipolar substance (a substance with high electron-transport property and high hole-transport property, also referred to as a bipolar material), or the like.

[0277] The light-emitting device can be made of either a low-molecular-weight compound or a high-molecular-weight compound, and may contain an inorganic compound. The layers constituting the light-emitting device can be formed by a method such as vapor deposition (including vacuum vapor deposition), transfer, printing, inkjet printing, or coating.

[0278] For example, the EL layer 113a, the EL layer 113b, and the EL layer 113c may each have one or more of a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer, an electron transport layer, and an electron injection layer.

[0279] The EL layer may include one or more of a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer, an electron transport layer, and an electron injection layer as a layer common to all colors. For example, a carrier injection layer (hole injection layer or electron injection layer) may be formed as layer 114. Note that all layers of the EL layer may be formed separately for each color. In other words, the EL layer does not need to include a layer common to all colors.

[0280] Each of the EL layers 113a, 113b, and 113c preferably includes a light-emitting layer and a carrier transport layer on the light-emitting layer. This prevents the light-emitting layer from being exposed to the outermost surface during the manufacturing process of the display device 100, thereby reducing damage to the light-emitting layer. This improves the reliability of the light-emitting device.

[0281] The hole injection layer is a layer that injects holes from the anode into the hole transport layer and contains a substance with high hole injection properties, such as an aromatic amine compound and a composite material containing a hole transport material and an acceptor material (electron acceptor material).

[0282] The hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light emitting layer. The hole transport layer is a layer that contains a hole transport material. The hole transport material is 1×10 −６ cm ２A substance having a hole mobility of 1 / Vs or more is preferred. Note that other substances can also be used as long as they have a higher hole transporting property than electron transporting property. As the hole transporting material, a substance having a high hole transporting property, such as a π-electron-rich heteroaromatic compound (e.g., a carbazole derivative, a thiophene derivative, a furan derivative, etc.) or an aromatic amine (a compound having an aromatic amine skeleton), is preferred.

[0283] The electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light emitting layer. The electron transport layer is a layer that contains an electron transporting material. The electron transporting material has a concentration of 1×10 −６ cm ２ / Vs or more is preferred. Note that other substances can also be used as long as they have a higher electron transporting property than holes. As the electron-transporting material, metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, metal complexes having a thiazole skeleton, and the like, 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 including nitrogen-containing heteroaromatic compounds can be used.

[0284] The electron injection layer is a layer that injects electrons from the cathode into the electron transport layer and contains a substance with high electron injection properties. Examples of the substance with high electron injection properties include alkali metals, alkaline earth metals, and compounds thereof. Examples of the substance with high electron injection properties include a composite material containing an electron transport material and a donor material (electron donor material).

[0285] The electron injection layer may be formed of, for example, lithium, cesium, ytterbium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ｘ, where X is an arbitrary number), 8-(quinolinolato)lithium (abbreviation: Liq), 2-(2-pyridyl)phenolatolithium (abbreviation: LiPP), 2-(2-pyridyl)-3-pyridinolatolithium (abbreviation: LiPPy), 4-phenyl-2-(2-pyridyl)phenolatolithium (abbreviation: LiPPP), lithium oxide (LiO ｘ ), alkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used. The electron injection layer may have a stacked structure of two or more layers. For example, the stacked structure may have a structure in which lithium fluoride is used in the first layer and ytterbium is provided in the second layer.

[0286] Alternatively, an electron transporting material may be used for the electron injection layer. For example, a compound having an unshared electron pair and an electron-deficient heteroaromatic ring may 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), and a triazine ring may be used.

[0287] The organic compound having an unshared electron pair preferably has a lowest unoccupied molecular orbital (LUMO) of -3.6 eV to -2.3 eV. Generally, the highest occupied molecular orbital (HOMO) level and the LUMO level of an organic compound can be estimated by cyclic voltammetry (CV), photoelectron spectroscopy, optical absorption spectroscopy, inverse photoelectron spectroscopy, or the like.

[0288] For example, 4,7-diphenyl-1,10-phenanthroline (abbreviation: BPhen), 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen), diquinoxalino<2,3-a:2′,3′-c>phenazine (abbreviation: HATNA), 2,4,6-tris<3′-(pyridin-3-yl)biphenyl-3-yl>-1,3,5-triazine (abbreviation: TmPPPyTz), etc. can be used as the organic compound having an unshared electron pair. Note that NBPhen has a higher glass transition temperature (Tg) and is superior in heat resistance compared to BPhen.

[0289] When a light-emitting device with a tandem structure is fabricated, an intermediate layer is provided between two light-emitting units, which has the function of injecting electrons into one of the two light-emitting units and holes into the other when a voltage is applied between a pair of electrodes.

[0290] For the intermediate layer, a material applicable to an electron injection layer, such as lithium, can be suitably used. For the intermediate layer, a material applicable to a hole injection layer can be suitably used. For the intermediate layer, a layer containing a hole transport material and an acceptor material (electron acceptor material) can be suitably used. For the intermediate layer, a layer containing an electron transport material and a donor material can be suitably used. By forming an intermediate layer having such a layer, an increase in driving voltage can be suppressed when light-emitting units are stacked.

[0291] The active layer includes a semiconductor. Examples of the semiconductor include an inorganic semiconductor such as silicon and an organic semiconductor including an organic compound. In this embodiment, an example in which an organic semiconductor is used as the semiconductor included in the active layer is shown. By using an organic semiconductor, the light-emitting layer and the active layer can be formed by the same method (for example, vacuum deposition), which is preferable because a common manufacturing device can be used.

[0292] As the n-type semiconductor material of the active layer, fullerene (e.g., C ６０ Fullerene, C ７０Examples of electron-accepting organic semiconductor materials include fullerenes and fullerene derivatives. Fullerenes have a soccer ball-like shape, and this shape is energetically stable. Fullerenes have deep (low) HOMO and LUMO levels. Because fullerenes have a deep LUMO level, they have extremely high electron-accepting (acceptor) properties. Normally, when π-electron conjugation (resonance) spreads on a plane, as in benzene, electron-donating (donor) properties increase, but fullerenes have a spherical shape, so they have high electron-accepting properties despite the wide spread of π-electrons. High electron-accepting properties cause charge separation quickly and efficiently, making them useful as light-receiving elements. C ６０ Fullerene, C ７０ Both fullerenes and fluorenes have a wide absorption band in the visible light region, especially C ７０ Fullerene is C ６０ It is preferable because it has a larger π-electron conjugated system than fullerene and has a wide absorption band in the long wavelength region. Other fullerene derivatives include [6,6]-Phenyl-C71-butylic acid methyl ester (abbreviation: PC70BM), [6,6]-Phenyl-C61-butylic acid methyl ester (abbreviation: PC60BM), and 1',1",4',4"-Tetrahydro-di[1,4]methanenaphthaleno[1,2:2',3',56,60:2"3"][5,6]fullerene-C60 (abbreviation: ICBA).

[0293] 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.

[0294] Examples of p-type semiconductor materials contained in the active layer include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanthene (DBP), zinc phthalocyanine (ZnPc), tin(II) phthalocyanine (SnPc), and quinacridone.

[0295] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, compounds having an aromatic amine skeleton, etc. Further examples of p-type semiconductor materials 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, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, polythiophene derivatives, etc.

[0296] The HOMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the HOMO level of the electron-accepting organic semiconductor material, and the LUMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the LUMO level of the electron-accepting organic semiconductor material.

[0297] It is preferable to use a spherical fullerene as the electron-accepting organic semiconductor material and a planar organic semiconductor material as the electron-donating organic semiconductor material. Molecules with similar shapes tend to aggregate together, and when molecules of the same type aggregate, the energy levels of their molecular orbitals become close, which can improve carrier transport properties.

[0298] For example, the active layer is preferably formed by co-evaporating an n-type semiconductor and a p-type semiconductor, or may be formed by laminating an n-type semiconductor and a p-type semiconductor.

[0299] The light-emitting element and the light-receiving element can be made of either a low-molecular-weight compound or a high-molecular-weight compound, and may contain an inorganic compound. The layers constituting the light-emitting element and the light-receiving element can be formed by a method such as a vapor deposition method (including a vacuum vapor deposition method), a transfer method, a printing method, an inkjet method, or a coating method.

[0300] For example, a polymer compound such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS) can be used as the hole transport material, and an inorganic compound such as molybdenum oxide or copper iodide (CuI) can be used as the electron transport material.

[0301] The active layer can be formed using a polymer compound 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 a PBDB-T derivative, which functions as a donor. For example, a method of dispersing an acceptor material in PBDB-T or a PBDB-T derivative can be used.

[0302] Three or more materials may be mixed in the active layer. For example, in order to expand the wavelength range, a third material may be mixed in addition to an n-type semiconductor material and a p-type semiconductor material. In this case, the third material may be a low-molecular-weight compound or a high-molecular-weight compound.

[0303] The side surfaces of the pixel electrodes 111a, 111b, 111c, 111d, the EL layers 113a, 113b, 113c, and the light-receiving layer 113d are covered with insulating layers 125 and 127. This prevents the layer 114 (or the common electrode 115) from coming into contact with any of the side surfaces of the pixel electrodes 111a, 111b, 111c, 111d, the EL layers 113a, 113b, 113c, and the light-receiving layer 113d, thereby preventing short circuits between the light-emitting device and the light-receiving device.

[0304] The insulating layer 125 preferably covers at least the side surfaces of the pixel electrodes 111a, 111b, 111c, and 111d. Furthermore, the insulating layer 125 preferably covers the side surfaces of the EL layers 113a, 113b, 113c, and the light-receiving layer 113d. The insulating layer 125 may be configured to be in contact with the side surfaces of each of the pixel electrodes 111a, 111b, 111c, 111d, EL layers 113a, 113b, 113c, and the light-receiving layer 113d.

[0305] The insulating layer 127 is provided on the insulating layer 125 so as to fill recesses formed in the insulating layer 125. The insulating layer 127 can be configured to overlap with the side surfaces of the pixel electrodes 111a, 111b, 111c, 111d, the EL layers 113a, 113b, 113c, and the light-receiving layer 113d, with the insulating layer 125 interposed therebetween.

[0306] Note that either the insulating layer 125 or the insulating layer 127 does not necessarily have to be provided. For example, when the insulating layer 125 is not provided, the insulating layer 127 can be configured to be in contact with the side surfaces of the EL layer 113a, the EL layer 113b, the EL layer 113c, and the light-receiving layer 113d. The insulating layer 127 can be provided on the layer 101 so as to fill the gap between the EL layer of the light-emitting device and the light-receiving layer of the light-receiving device.

[0307] The layer 114 and the common electrode 115 are provided over the EL layer 113a, the EL layer 113b, the EL layer 113c, the light-receiving layer 113d, the insulating layer 125, and the insulating layer 127. Before the insulating layer 125 and the insulating layer 127 are provided, a step exists between a region where the pixel electrode is provided and a region where the pixel electrode is not provided (a region between the light-emitting device and the light-receiving device). The display device of one embodiment of the present invention includes the insulating layer 125 and the insulating layer 127, which can flatten the step and improve the coverage of the layer 114 and the common electrode 115. Therefore, poor connection due to a step in the common electrode 115 can be suppressed. Alternatively, an increase in electrical resistance due to a local thinning of the common electrode 115 due to the step can be suppressed. Note that in this specification and the like, a step refers to a phenomenon in which a layer, a film, or an electrode is separated due to the shape of the surface on which it is formed (for example, a step).

[0308] In order to improve the flatness of the formation surfaces of the layer 114 and the common electrode 115, it is preferable that the height of the upper surface of the insulating layer 125 and the upper surface of the insulating layer 127 be equal to or approximately equal to the height of the upper surface of at least one of the EL layer 113a, the EL layer 113b, the EL layer 113c, and the light-receiving layer 113d. The upper surface of the insulating layer 127 preferably has a flat shape, and may have protrusions or recesses.

[0309] The insulating layer 125 has a region in contact with the side surfaces of the EL layer 113 a, the EL layer 113 b, the EL layer 113 c, and the light-receiving layer 113 d, and functions as a protective insulating layer for the EL layer 113 a, the EL layer 113 b, the EL layer 113 c, and the light-receiving layer 113 d. By providing the insulating layer 125, impurities (oxygen, moisture, etc.) can be prevented from entering the interior from the side surfaces of the EL layer 113 a, the EL layer 113 b, the EL layer 113 c, and the light-receiving layer 113 d, thereby providing a highly reliable display device.

[0310] If the width (thickness) of the insulating layer 125 in the region in contact with the side surfaces of the EL layers 113 a, 113 b, 113 c, and the light-receiving layer 113 d is large in cross-sectional view, the distance between the EL layers 113 a, 113 b, 113 c, and the light-receiving layer 113 d will be large, which may result in a low aperture ratio. Also, if the width (thickness) of the insulating layer 125 is small, the effect of suppressing impurities from penetrating into the interior from the side surfaces of the EL layers 113 a, 113 b, 113 c, and the light-receiving layer 113 d may be reduced.

[0311] The width (thickness) of the insulating layer 125 in a region in contact with the side surfaces of the EL layer 113a, the EL layer 113b, the EL layer 113c, and the light-receiving layer 113d is preferably 3 nm to 200 nm, more preferably 3 nm to 150 nm, further preferably 5 nm to 150 nm, further preferably 5 nm to 100 nm, further preferably 10 nm to 100 nm, and further preferably 10 nm to 50 nm. By setting the width (thickness) of the insulating layer 125 in the above range, a display device having a high aperture ratio and high reliability can be obtained.

[0312] The insulating layer 125 can include an inorganic material. For example, an inorganic insulating film such as an insulating oxide film, an insulating nitride film, an insulating oxynitride film, or an insulating nitride oxide film can be used for the insulating layer 125. The insulating layer 125 may have a single-layer structure or a stacked-layer structure.

[0313] The insulating layer 125 can be formed by a sputtering method, a chemical vapor deposition (CVD) method, a pulsed laser deposition (PLD) method, an atomic layer deposition (ALD) method, or the like. The insulating layer 125 is preferably formed by an ALD method, which has good coverage. The ALD method can be preferably used because it causes little damage to a surface on which the insulating layer 125 is formed.

[0314] Examples of oxide insulating films include silicon oxide films, aluminum oxide films, magnesium oxide films, indium gallium zinc oxide films, gallium oxide films, germanium oxide films, yttrium oxide films, zirconium oxide films, lanthanum oxide films, neodymium oxide films, hafnium oxide films, and tantalum oxide films. Examples of nitride insulating films include silicon nitride films and aluminum nitride films. Examples of oxynitride insulating films include silicon oxynitride films and aluminum oxynitride films. Examples of nitride oxide insulating films include silicon nitride oxide films and aluminum nitride oxide films. Aluminum oxide is particularly preferable because it has a high etching selectivity with respect to the EL layer and has a function of protecting the EL layer in the formation of the insulating layer 127 described later. In particular, by using an inorganic insulating film such as an aluminum oxide film, hafnium oxide film, or silicon oxide film formed by an ALD method as the insulating layer 125, an insulating layer 125 with few pinholes and excellent protection of the EL layer can be formed.

[0315] In this specification and elsewhere, an oxynitride refers to a material whose composition contains more oxygen than nitrogen, and a nitride oxide refers to a material whose composition contains more nitrogen than oxygen. For example, silicon oxynitride refers to a material whose composition contains more oxygen than nitrogen, and silicon nitride oxide refers to a material whose composition contains more nitrogen than oxygen.

[0316] The insulating layer 127 provided on the insulating layer 125 has the function of planarizing recesses formed in the insulating layer 125 between adjacent light-emitting devices. In other words, the insulating layer 127 improves the flatness of the surface on which the common electrode 115 is formed. The insulating layer 127 can be preferably an insulating layer containing an organic material. For example, the insulating layer 127 can be made of acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, or precursors of these resins. Alternatively, the insulating layer 127 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. Alternatively, the insulating layer 127 can be made of a photosensitive resin. A photoresist can be used as the photosensitive resin. The photosensitive resin can be a positive-type material or a negative-type material.

[0317] The difference in height between the upper surface of the insulating layer 127 and the upper surface of any one of the EL layers 113a, 113b, 113c, and the light-receiving layer 113d is, for example, preferably 0.5 times or less, and more preferably 0.3 times or less, the thickness of the insulating layer 127. Alternatively, for example, the insulating layer 127 may be provided so that the upper surface of any one of the EL layers 113a, 113b, 113c, and the light-receiving layer 113d is higher than the upper surface of the insulating layer 127. Alternatively, for example, the insulating layer 127 may be provided so that the upper surface of the insulating layer 127 is higher than the upper surfaces of the light-emitting layers of the EL layers 113a, 113b, and 113c, and higher than the upper surface of the active layer of the light-receiving layer 113d.

[0318] It is preferable that the light-emitting device 130a, the light-emitting device 130b, the light-emitting device 130c, and the light-receiving device 130d have protective layers 131 and 132. By providing the protective layers 131 and 132, the reliability of the light-emitting devices and the light-receiving devices can be improved.

[0319] There is no limitation on the conductivity of the protective layer 131 and the protective layer 132. The protective layer 131 and the protective layer 132 can be formed using at least one of an insulating film, a semiconductor film, and a conductive film.

[0320] The protective layer 131 and the protective layer 132 have an inorganic film, which prevents oxidation of the common electrode 115 and suppresses impurities (moisture, oxygen, etc.) from entering the light-emitting device 130a, the light-emitting device 130b, the light-emitting device 130c, and the light-receiving device 130d, thereby suppressing deterioration of the light-emitting devices and the light-receiving devices and improving the reliability of the display device.

[0321] The protective layer 131 and the protective layer 132 can be formed using, for example, an inorganic insulating film such as an oxide insulating film, a nitride insulating film, an oxynitride insulating film, or a nitride oxide insulating film. Examples of oxide insulating films include a silicon oxide film, an aluminum oxide film, a gallium oxide film, a germanium oxide film, an yttrium oxide film, a zirconium oxide film, a lanthanum oxide film, a neodymium oxide film, a hafnium oxide film, and a tantalum oxide film. Examples of nitride insulating films include a silicon nitride film and an aluminum nitride film. Examples of oxynitride insulating films include a silicon oxynitride film and an aluminum oxynitride film. Examples of nitride oxide insulating films include a silicon nitride oxide film and an aluminum nitride oxide film.

[0322] Each of the protective layers 131 and 132 preferably includes an insulating nitride film or an insulating nitride oxide film, and more preferably includes an insulating nitride film.

[0323] The protective layer 131 and the protective layer 132 may be formed using an inorganic film containing In—Sn oxide (also referred to as ITO), In—Zn oxide, Ga—Zn oxide, Al—Zn oxide, indium gallium zinc oxide (In—Ga—Zn oxide, also referred to as IGZO), or the like. The inorganic film preferably has high resistance, specifically, preferably has higher resistance than the common electrode 115. The inorganic film may further contain nitrogen.

[0324] When light is emitted from the light-emitting device and incident on the light-receiving device via the protective layers 131 and 132, it is preferable that the protective layers 131 and 132 have high transparency to visible light. For example, ITO, IGZO, and aluminum oxide are preferable because they are inorganic materials that have high transparency to visible light.

[0325] For example, a stacked structure of an aluminum oxide film and a silicon nitride film on the aluminum oxide film, or a stacked structure of an aluminum oxide film and an IGZO film on the aluminum oxide film can be used as the protective layer 131 and the protective layer 132. By using such a stacked structure, impurities (water, oxygen, etc.) can be prevented from entering the EL layer side.

[0326] Furthermore, the protective layer 131 and the protective layer 132 may include an organic film. For example, the protective layer 132 may include both an organic film and an inorganic film.

[0327] Different film formation methods may be used for the protective layer 131 and the protective layer 132. Specifically, the protective layer 131 may be formed by an ALD method, and the protective layer 132 may be formed by a sputtering method.

[0328] The upper end portions of the pixel electrodes 111a, 111b, 111c, and 111d are not covered with an insulating layer, which allows the distance between adjacent light-emitting devices and light-receiving devices to be extremely narrow, thereby enabling a high-definition or high-resolution display device.

[0329] In this specification, etc., a device fabricated using a metal mask or an FMM (fine metal mask, high-resolution metal mask) may be referred to as a device with an MM (metal mask) structure. Also, in this specification, etc., a device fabricated without using a metal mask or an FMM may be referred to as a device with an MML (metal maskless) structure.

[0330] In this specification and the like, a structure in which different light-emitting layers are fabricated or different light-emitting layers are painted for each color light-emitting device (here, blue (B), green (G), and red (R)) may be referred to as an SBS (Side By Side) structure. The SBS structure allows the materials and configuration to be optimized for each light-emitting device, increasing the freedom of material and configuration selection and facilitating improvements in brightness and reliability.

[0331] In this specification and the like, a light-emitting device capable of emitting white light may be referred to as a white light-emitting device. Note that a white light-emitting device can be combined with a colored layer (for example, a color filter) to realize a full-color display device.

[0332] Here, light-emitting devices can be broadly divided into single structures and tandem structures. A single-structure device has one light-emitting unit between a pair of electrodes, and the light-emitting unit preferably includes one or more light-emitting layers. To obtain white light emission, two or more light-emitting layers may be selected so that the light emitted from each of the two or more light-emitting layers has a complementary color relationship. For example, by making the emission color of the first light-emitting layer and the emission color of the second light-emitting layer complementary to each other, a configuration in which the light-emitting device as a whole emits white light can be obtained. Furthermore, in the case of a light-emitting device having three or more light-emitting layers, the emission colors of the respective light-emitting layers can be mixed to emit white light.

[0333] A tandem-structure device preferably has two or more light-emitting units between a pair of electrodes, and each light-emitting unit preferably includes one or more light-emitting layers. To obtain white light emission, light from the light-emitting layers of the light-emitting units may be combined to obtain white light emission. The configuration for obtaining white light emission is the same as that of the single-structure device. In a tandem-structure device, it is preferable to provide an intermediate layer such as a charge-generating layer between the light-emitting units.

[0334] When the above-described white light-emitting device (single structure or tandem structure) is compared with a light-emitting device having an SBS structure, the light-emitting device having an SBS structure can reduce power consumption compared to the white light-emitting device. When it is desired to reduce power consumption, it is preferable to use a light-emitting device having an SBS structure. On the other hand, the manufacturing process of a white light-emitting device is simpler than that of a light-emitting device having an SBS structure, and therefore the manufacturing cost can be reduced or the manufacturing yield can be increased, making it preferable.

[0335] The display device of this embodiment can reduce the distance between light-emitting devices. Specifically, the distance between light-emitting devices, the distance between EL layers, or the distance between pixel electrodes can be less than 10 μm, 5 μm or less, 3 μm or less, 2 μm or less, 1 μm or less, 500 nm or less, 200 nm or less, 100 nm or less, 90 nm or less, 70 nm or less, 50 nm or less, 30 nm or less, 20 nm or less, 15 nm or less, or 10 nm or less. In other words, the distance between the side surface of the EL layer 113a and the side surface of the EL layer 113b or the distance between the side surface of the EL layer 113b and the side surface of the EL layer 113c has a region of 1 μm or less, preferably a region of 0.5 μm (500 nm) or less, and more preferably a region of 100 nm or less.

[0336] Similarly, the display device of this embodiment can reduce the distance between light-receiving devices. Specifically, the distance between light-receiving devices, the distance between light-receiving layers, or the distance between pixel electrodes can be less than 10 μm, 5 μm or less, 3 μm or less, 2 μm or less, 1 μm or less, 500 nm or less, 200 nm or less, 100 nm or less, 90 nm or less, 70 nm or less, 50 nm or less, 30 nm or less, 20 nm or less, 15 nm or less, or 10 nm or less. In other words, the distance between the side surface of one light-receiving layer and the side surface of an adjacent light-receiving layer is 1 μm or less in a region, preferably 0.5 μm (500 nm) or less in a region, and more preferably 100 nm or less in a region.

[0337] The display device of this embodiment can reduce the distance between the light-emitting device and the light-receiving device. Specifically, the distance between the light-emitting device and the light-receiving device, the distance between the EL layer and the light-receiving layer, or the distance between the pixel electrodes can be less than 20 μm, 10 μm or less, 5 μm or less, 3 μm or less, 2 μm or less, 1 μm or less, 500 nm or less, 200 nm or less, 100 nm or less, 90 nm or less, 70 nm or less, 50 nm or less, 30 nm or less, 20 nm or less, 15 nm or less, or 10 nm or less. In other words, the distance between the side surface of EL layer 113a and the side surface of light-receiving layer 113d, the distance between the side surface of EL layer 113b and the side surface of light-receiving layer 113d, or the distance between the side surface of EL layer 113c and the side surface of light-receiving layer 113d has a region of 1 μm or less, preferably a region of 0.5 μm (500 nm) or less, and more preferably a region of 100 nm or less.

[0338] A light-shielding layer may be provided on the surface of the substrate 120 facing the resin layer 122. Various optical members may be disposed on the outside of the substrate 120. Examples of optical members include a polarizing plate, a retardation plate, a light diffusion layer (such as a diffusion film), an anti-reflection layer, and a light-collecting film. The outside of the substrate 120 may also be provided with an anti-static film that suppresses the adhesion of dust, a water-repellent film that makes it difficult for dirt to adhere, a hard coat film that suppresses the occurrence of scratches during use, an impact absorbing layer, etc.

[0339] The substrate 120 can be made of glass, quartz, ceramic, sapphire, resin, metal, alloy, semiconductor, or the like. A material that transmits light is used for the substrate on the side from which light from the light-emitting device is extracted. Using a flexible material for the substrate 120 can increase the flexibility of the display device and realize a flexible display. A polarizing plate may also be used as the substrate 120.

[0340] The substrate 120 can be made of polyester resin such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), polyacrylonitrile resin, acrylic resin, polyimide resin, polymethyl methacrylate resin, polycarbonate (PC) resin, polyethersulfone (PES) resin, polyamide resin (nylon, aramid, etc.), polysiloxane resin, cycloolefin resin, polystyrene resin, polyamideimide resin, polyurethane resin, polyvinyl chloride resin, polyvinylidene chloride resin, polypropylene resin, polytetrafluoroethylene (PTFE) resin, ABS resin, cellulose nanofiber, etc. The substrate 120 can also be made of glass having a thickness sufficient to provide flexibility.

[0341] When a circularly polarizing plate is superimposed on a display device, it is preferable that the display device has a substrate with high optical isotropy. A substrate with high optical isotropy has small birefringence (or a small amount of birefringence).

[0342] The absolute value of the retardation (phase difference) of a substrate having high optical isotropy is preferably 30 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less.

[0343] Examples of films with high optical isotropy include triacetyl cellulose (TAC, also known as cellulose triacetate) films, cycloolefin polymer (COP) films, cycloolefin copolymer (COC) films, and acrylic films.

[0344] When a film is used as a substrate, the film may absorb water, causing deformation such as wrinkles in the display panel. Therefore, it is preferable to use a film with low water absorption for the substrate. For example, it is preferable to use a film with a water absorption rate of 1% or less, more preferably 0.1% or less, and even more preferably 0.01% or less.

[0345] The resin layer 122 can be made of various curable adhesives, such as a photo-curable adhesive (e.g., an ultraviolet curable adhesive), a reactive curable adhesive, a thermosetting adhesive, or an anaerobic adhesive. Examples of such adhesives include epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, and EVA (ethylene vinyl acetate) resin. Materials with low moisture permeability, such as epoxy resin, are particularly preferred. Two-component resins may also be used. Adhesive sheets or the like may also be used.

[0346] Materials that can be used for conductive layers such as the gate, source, and drain of a transistor, as well as various wirings and electrodes that constitute a display device include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, and tungsten, and alloys containing these metals as main components, etc. Films containing these materials can be used as a single layer or a stacked layer structure.

[0347] Examples of light-transmitting conductive materials include conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, and zinc oxide containing gallium, or graphene. Alternatively, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, and titanium, or alloy materials containing such metal materials, can be used. Alternatively, nitrides of such metal materials (e.g., titanium nitride) can be used. When using metal materials or alloy materials (or their nitrides), it is preferable to thin them sufficiently to ensure light-transmitting properties. A stacked film of the above materials can also be used as the conductive layer. For example, a stacked film of an alloy of silver and magnesium and indium tin oxide is preferable because it can enhance conductivity. These materials can also be used for conductive layers such as various wirings and electrodes constituting display devices, and conductive layers (conductive layers functioning as pixel electrodes or common electrodes) in light-emitting devices.

[0348] Examples of insulating materials that can be used for each insulating layer include resins such as acrylic resin and epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, and aluminum oxide.

[0349] <Pixel Layout> The pixel layout will now be described. There are no particular limitations on the arrangement of sub-pixels, and various methods can be applied. Examples of sub-pixel arrangements include a stripe arrangement, an S-stripe arrangement, a matrix arrangement, a delta arrangement, a Bayer arrangement, and a pentile arrangement.

[0350] Examples of the top surface shape of the subpixel include a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon, a polygon with rounded corners, an ellipse, a circle, etc. Here, the top surface shape of the subpixel corresponds to the top surface shape of the light-emitting region of the light-emitting device or the light-receiving region of the light-receiving device.

[0351] The pixels 110 shown in FIGS. 21A to 21C are arranged in a stripe pattern.

[0352] 21A to 21C , a display portion of a display device according to one embodiment of the present invention includes a plurality of pixels arranged in a matrix in the row and column directions. The display portion employing the pixel layouts shown in FIGS. 21A to 21C includes a first array in which subpixels 110a, 110b, 110c, and 110d are repeatedly arranged in this order in the row direction. Furthermore, the first array is repeatedly arranged in the column direction.

[0353] The display unit has a second array in which sub-pixels 110a are repeatedly arranged in the column direction, a third array in which sub-pixels 110b are repeatedly arranged in the column direction, a fourth array in which sub-pixels 110c are repeatedly arranged in the column direction, and a fifth array in which sub-pixels 110d are repeatedly arranged in the column direction. Furthermore, the second array, third array, fourth array, and fifth array are repeatedly arranged in this order in the row direction.

[0354] In the present embodiment and the like, in order to clearly explain the pixel layout, the horizontal direction in the drawings is the row direction and the vertical direction is the column direction. However, this is not limited thereto, and the row direction and the column direction can be interchanged. Therefore, in this specification and the like, one of the row direction and the column direction may be referred to as a first direction, and the other of the row direction and the column direction may be referred to as a second direction. The second direction is perpendicular to the first direction. Note that, when the top surface shape of the display unit is rectangular, the first direction and the second direction do not need to be parallel to the straight line portions of the outline of the display unit. Furthermore, the top surface shape of the display unit is not limited to a rectangle and may be a polygon or a curved shape (e.g., a circle, an ellipse), and the first direction and the second direction may be any direction relative to the display unit.

[0355] In the present embodiment and the like, in order to explain the pixel layout in an easy-to-understand manner, the order of the sub-pixels is shown from the left of the drawing, but this is not limited to this and can be changed to the order from the right. Similarly, the order of the sub-pixels is shown from the top of the drawing, but this is not limited to this and can be changed to the order from the bottom.

[0356] In this specification and the like, "repeatedly arranged" means that the minimum unit of the order of sub-pixels is arranged two or more times.

[0357] FIG. 21A shows an example in which each subpixel has a rectangular top surface shape, FIG. 21B shows an example in which each subpixel has a top surface shape that is a combination of two semicircles and a rectangle, and FIG. 21C shows an example in which each subpixel has an elliptical top surface shape.

[0358] In photolithography, the finer the pattern to be processed, the more significant the effect of light diffraction becomes. This reduces the fidelity of the photomask pattern when it is transferred by exposure, making it difficult to process the resist mask into the desired shape. Therefore, even if the photomask pattern is rectangular, it is likely to have rounded corners. As a result, the top surface shape of the subpixel may become a polygon with rounded corners, an ellipse, a circle, or the like.

[0359] Furthermore, in a manufacturing method of a display device according to one embodiment of the present invention, the EL layer or the light-receiving layer is processed into an island shape using a resist mask. The resist film formed on the EL layer or the light-receiving layer needs to be cured at a temperature lower than the heat-resistant temperature of the EL layer or the light-receiving layer. Therefore, depending on the heat-resistant temperature of the material for the EL layer, the heat-resistant temperature of the material for the light-receiving layer, and the curing temperature of the resist material, the resist film may not be sufficiently cured. A resist film that is not sufficiently cured may have a shape that deviates from the desired shape during processing. As a result, the top surface shape of the EL layer or the light-receiving layer may be a polygon with rounded corners, an ellipse, a circle, or the like. For example, when a resist mask with a square top surface shape is formed, a resist mask with a circular top surface shape may be formed, resulting in a circular top surface shape of the EL layer or the light-receiving layer.

[0360] In order to form the top surfaces of the EL layer and the light-receiving layer into the desired shapes, a technique for correcting the mask pattern in advance (OPC (Optical Proximity Correction) technique) may be used so that the design pattern matches the transfer pattern. Specifically, the OPC technique adds a correction pattern to the corners of figures on the mask pattern.

[0361] The pixels 110 shown in FIGS. 21D to 21F are arranged in a matrix.

[0362] 21D to 21F , the display portion of the display device employing the pixel layouts shown in Fig. 21D to 21F includes a first array in which subpixels 110a and 110b are alternately arranged in the row direction, and a second array in which subpixels 110c and 110d are alternately arranged in the row direction. Furthermore, the first array and the second array are alternately arranged in this order in the column direction.

[0363] The display unit has a third array in which sub-pixels 110a and 110c are alternately arranged in the column direction, and a fourth array in which sub-pixels 110b and 110d are alternately arranged in the column direction. Furthermore, the third array and the fourth array are alternately arranged in the row direction.

[0364] Figure 21D is an example in which each sub-pixel has a square top surface shape, Figure 21E is an example in which each sub-pixel has an approximately square top surface shape with rounded corners, and Figure 21F is an example in which each sub-pixel has a circular top surface shape.

[0365] 21G shows an example in which one pixel 110 is configured with two rows and three columns. The pixel 110 has three subpixels (subpixels 110a, 110b, and 110c) in the top row (first row) and one subpixel (subpixel 110d) in the bottom row (second row). In other words, the pixel 110 has the subpixel 110a in the left column (first column), the subpixel 110b in the center column (second column), the subpixel 110c in the right column (third column), and further has the subpixel 110d across these three columns.

[0366] As shown in Figure 21G, the subpixels may have different sizes. Figure 21G shows a configuration in which the subpixel 110d is larger than the subpixels 110a to 110c. Figure 21H shows a configuration in which the subpixels 110b and 110c are larger than the subpixel 110a, and the subpixel 110a is larger than the subpixel 110d. The pixel 110 shown in Figure 21H has two subpixels (subpixels 110a and 110d) in the left column (first column), the subpixel 110b in the center column (second column), and the subpixel 110c in the right column (third column).

[0367] 21G has a first array in which subpixels 110a, 110b, and 110c are repeatedly arranged in this order in the row direction, and a second array in which subpixels 110d are repeatedly arranged in the row direction. Furthermore, the first array and the second array are repeatedly arranged alternately in the column direction.

[0368] The display unit has a third array in which the sub-pixels 110a and 110d are alternately arranged in the column direction, a fourth array in which the sub-pixels 110b and 110d are alternately arranged in the column direction, and a fifth array in which the sub-pixels 110c and 110d are alternately arranged in the column direction. Furthermore, the third array, the fourth array, and the fifth array are alternately arranged in this order in the row direction.

[0369] 21H has a first array in which subpixels 110a, 110b, and 110c are repeatedly arranged in this order in the row direction, and a second array in which subpixels 110d, 110b, and 110c are repeatedly arranged in this order in the row direction. Furthermore, the first array and the second array are repeatedly arranged alternately in the column direction.

[0370] The display unit has a third array in which sub-pixels 110a and 110d are alternately arranged in the column direction, a fourth array in which sub-pixels 110b are repeatedly arranged in the column direction, and a fifth array in which sub-pixels 110c are repeatedly arranged in the column direction. Furthermore, the third array, the fourth array, and the fifth array are repeatedly arranged in this order in the row direction.

[0371] 21I shows an example in which one pixel 110 is configured with two rows and three columns. The pixel 110 has subpixels 110a, 110b, 110c, and three subpixels 110d. The pixel 110 has three subpixels (subpixels 110a, 110b, and 110c) in the top row (first row) and three subpixels (three subpixels 110d) in the bottom row (second row). In other words, the pixel 110 has two subpixels (subpixels 110a and 110d) in the left column (first column), two subpixels (subpixels 110b and 110d) in the center column (second column), and two subpixels (subpixels 110c and 110d) in the right column (third column).

[0372] 21I is applied to a display section of a display device having a first array in which subpixels 110a, 110b, and 110c are repeatedly arranged in this order in the row direction, and a second array in which subpixels 110d are repeatedly arranged in the row direction. Furthermore, the first array and the second array are repeatedly arranged alternately in the column direction.

[0373] The display unit has a third array in which the sub-pixels 110a and 110d are alternately arranged in the column direction, a fourth array in which the sub-pixels 110b and 110d are alternately arranged in the column direction, and a fifth array in which the sub-pixels 110c and 110d are alternately arranged in the column direction. Furthermore, the third array, the fourth array, and the fifth array are alternately arranged in this order in the row direction.

[0374] 21A to 21I , the pixel 110 is composed of four subpixels: 110a, 110b, 110c, and 110d. The subpixels 110a, 110b, 110c, and 110d each have a light-emitting device or a light-receiving device that emits light in a different wavelength region. For example, as shown in FIGS. 22A to 22E , the subpixel 110a may be a subpixel R that emits red light, the subpixel 110b may be a subpixel G that emits green light, the subpixel 110c may be a subpixel B that emits blue light, and the subpixel 110d may be a subpixel PS that receives light.

[0375] 22A has a first array in which subpixels R, G, B, and PS are repeatedly arranged in this order in the row direction, and further, the first array is repeatedly arranged in the column direction.

[0376] The display unit has a second array in which sub-pixels R are repeatedly arranged in the column direction, a third array in which sub-pixels G are repeatedly arranged in the column direction, a fourth array in which sub-pixels B are repeatedly arranged in the column direction, and a fifth array in which sub-pixels PS are repeatedly arranged in the column direction. Furthermore, the second array, the third array, the fourth array, and the fifth array are repeatedly arranged in this order in the row direction.

[0377] 22B is applied to a display unit having a first array in which subpixels R and G are alternately arranged in the row direction, and a second array in which subpixels B and PS are alternately arranged in the row direction. Furthermore, the first array and the second array are alternately arranged in this order in the column direction.

[0378] The display unit has a third array in which subpixels R and B are alternately arranged in the column direction, and a fourth array in which subpixels G and PS are alternately arranged in the column direction. Furthermore, the third array and the fourth array are alternately arranged in the row direction.

[0379] 22C , the display section of the display device employs a first array in which subpixels R, G, and B are repeatedly arranged in this order in the row direction, and a second array in which subpixels PS are repeatedly arranged in the row direction. Furthermore, the first array and the second array are repeatedly arranged alternately in the column direction.

[0380] The display unit has a third array in which subpixels R and PS are alternately arranged in the column direction, a fourth array in which subpixels G and PS are alternately arranged in the column direction, and a fifth array in which subpixels B and PS are alternately arranged in the column direction, and further, the third array, the fourth array, and the fifth array are alternately arranged in this order in the row direction.

[0381] 22D is applied to a display unit having a first array in which subpixels R, G, and B are repeatedly arranged in this order in the row direction, and a second array in which subpixels PS, G, and B are repeatedly arranged in this order in the row direction. Furthermore, the first array and the second array are repeatedly arranged alternately in the column direction.

[0382] The display unit has a third array in which sub-pixels R and sub-pixels PS are alternately arranged in the column direction, a fourth array in which sub-pixels G are repeatedly arranged in the column direction, and a fifth array in which sub-pixels B are repeatedly arranged in the column direction. Furthermore, the third array, fourth array, and fifth array are repeatedly arranged in this order in the row direction.

[0383] 22E , the display section of the display device employs a first array in which subpixels R, G, and B are repeatedly arranged in this order in the row direction, and a second array in which subpixels PS are repeatedly arranged in the row direction. Furthermore, the first array and the second array are alternately arranged in the column direction.

[0384] The display unit has a third array in which subpixels R and PS are alternately arranged in the column direction, a fourth array in which subpixels G and PS are alternately arranged in the column direction, and a fifth array in which subpixels B and PS are alternately arranged in the column direction, and further has the third array, fourth array, and fifth array arranged in this order in the row direction.

[0385] The light-emitting areas of the subpixels R, G, and B, each having a light-emitting device, may be the same or different from one another. For example, the light-emitting areas of the subpixels having a light-emitting device may be determined based on the lifetime of the light-emitting device. It is preferable to make the light-emitting area of ​​the subpixel having a light-emitting device with a short lifetime larger than the light-emitting areas of the other subpixels.

[0386] 22D shows an example in which the light-emitting areas of subpixels G and B are larger than that of subpixel R. This configuration is suitable for use in cases where the lifespans of the light-emitting devices that emit green light and blue light are shorter than that of the light-emitting devices that emit red light. In subpixels G and B with larger light-emitting areas, the current density applied to the light-emitting devices that emit green light and blue light in each subpixel is lower, thereby extending the lifespans of the light-emitting devices. In other words, a highly reliable display device can be obtained.

[0387] Examples of pixel layouts that differ from those shown in FIGS. 21A to 21I and 22A to 22E are shown in FIGS. 23A and 23B.

[0388] 23A shows four pixels, with adjacent pixels 110A and 110B having different subpixels. The pixel 110A has three subpixels: subpixel 110a, subpixel 110b, and subpixel 110d. The pixel 110B adjacent to the pixel 110A has subpixels 110b, subpixel 110c, and subpixel 110d. That is, in the column and row directions, pixels 110A including subpixel 110a and pixels 110B not including subpixel 110a are alternately arranged. Similarly, in the column and row directions, pixels 110A not including subpixel 110c and pixels 110B including subpixel 110c are alternately arranged.

[0389] The pixel 110A is configured in two rows and two columns, and has two subpixels (subpixels 110b and 110d) in the left column (first column) and one subpixel (subpixel 110a) in the right column (second column). In other words, the pixel 110A has two subpixels (subpixels 110a and 110b) in the top row (first row), two subpixels (subpixels 110a and 110d) in the bottom row (second row), and further has subpixels 110a across these two rows.

[0390] Pixel 110B is configured with two rows and two columns, and has two subpixels (subpixels 110b and 110d) in the left column (first column) and one subpixel (subpixel 110c) in the right column (second column). In other words, pixel 110A has two subpixels (subpixels 110b and 110c) in the top row (first row), two subpixels (subpixels 110c and 110d) in the bottom row (second row), and further has subpixel 110c spanning these two rows.

[0391] The pixel shown in FIG. 23A has two pixels, pixel 110A and pixel 110B, each having four subpixels: subpixel 110a, subpixel 110b, subpixel 110c, and subpixel 110d. The two pixels, pixel 110A and pixel 110B, each have one subpixel 110a, two subpixels 110b, one subpixel 110c, and two subpixels 110d. This configuration allows the area of ​​the subpixels to be increased while maintaining a pseudo-high resolution, thereby reducing the required processing accuracy. In other words, compared with the same processing accuracy, it is possible to manufacture a display device with higher resolution. Furthermore, the number of transistors per area can be reduced, thereby improving productivity. Therefore, a pseudo-high-resolution display device can be manufactured with high productivity.

[0392] 23A , the display section of the display device employs a first array ARR1 in which subpixels 110b, 110a, 110b, and 110c are repeatedly arranged in this order in the row direction, and a second array ARR2 in which subpixels 110d, 110a, 110d, and 110c are repeatedly arranged in this order in the row direction. Furthermore, the first array ARR1 and the second array ARR2 are repeatedly arranged alternately in the column direction.

[0393] The display unit has a third array ARR3 in which the sub-pixels 110b and 110d are alternately arranged in the column direction, and a fourth array ARR4 in which the sub-pixels 110a and 110c are alternately arranged in the column direction. Furthermore, the third array ARR3 and the fourth array ARR4 are alternately arranged in the row direction.

[0394] In pixel 110A, it is preferable that subpixel 110a has a larger area than both subpixels 110b and 110d, and in pixel 110B, subpixel 110c has a larger area than both subpixels 110b and 110d. Furthermore, it is preferable that the subpixel with the largest area in pixel 110A (subpixel 110a in this case) is different from the subpixel with the largest area in pixel 110B (subpixel 110c in this case).

[0395] In this specification and the like, the light-emitting area of ​​a sub-pixel having a light-emitting device may be referred to as the area of ​​the sub-pixel. Similarly, the light-receiving area of ​​a sub-pixel having a light-receiving device may be referred to as the area of ​​the sub-pixel.

[0396] In Figure 23A, the subpixels 110a and 110c are shown with the same area, and the subpixels 110b and 110d are shown with the same area, but this is not a limitation of one embodiment of the present invention. The areas of the subpixels 110a and 110c may be different. The areas of the subpixels 110b and 110d may also be different. Figure 23B shows an example in which the area of ​​the subpixel 110b is larger than the area of ​​the subpixel 110d. Note that the areas of the subpixels 110b and 110d may be different between the pixel 110A and the pixel 110B.

[0397] 24A and 24B , the subpixel 110a may be a subpixel R having a function of emitting red light, the subpixel 110b may be a subpixel G having a function of emitting green light, the subpixel 110c may be a subpixel B having a function of emitting blue light, and the subpixel 110d may be a subpixel PS having a light-receiving function.

[0398] One pixel can be configured with light-emitting devices of two of the three colors, red (R), green (G), and blue (B). A light-receiving device can be provided in any pixel. 24A and 24B show a configuration in which a pixel 110A has a sub-pixel R that emits red light, a sub-pixel G that emits green light, and a sub-pixel PS that receives light, and a pixel 110B has a sub-pixel B that emits blue light, a sub-pixel G that emits green light, and a sub-pixel PS that receives light.

[0399] 24A and 24B , the display section of the display device employs a first array ARR1 in which subpixels G, R, G, and B are repeatedly arranged in this order in the row direction, and a second array ARR2 in which subpixels PS, R, PS, and B are repeatedly arranged in this order in the row direction. Furthermore, the first array ARR1 and the second array ARR2 are repeatedly arranged alternately in the column direction.

[0400] The display unit has a third array ARR3 in which sub-pixels G and PS are alternately arranged in the column direction, and a fourth array ARR4 in which sub-pixels R and B are alternately arranged in the column direction. Furthermore, the third array ARR3 and the fourth array ARR4 are alternately arranged in the row direction.

[0401] 24A and 24B show an example in which both the pixel 110A and the pixel 110B are provided with a subpixel PS having a light-receiving device, but one embodiment of the present invention is not limited to this. If high accuracy is not required for the light-receiving function, pixels that do not include a subpixel PS may be provided. In other words, a configuration may be used in which pixels that include a subpixel PS and pixels that do not include a subpixel PS are provided.

[0402] 24A and 24B , the area of ​​subpixel G having the function of emitting green light is preferably smaller than the area of ​​subpixel R having the function of emitting red light and the area of ​​subpixel B having the function of emitting blue light. Because human luminosity for green is higher than that for red and blue, making the area of ​​subpixel G smaller than the areas of subpixels R and B makes it possible to obtain a display device that has an excellent balance of red (R), green (G), and blue (B) and high visibility.

[0403] 24A and 24B show a configuration in which the area of ​​subpixel G is smaller than the areas of subpixels R and B, but this aspect of the present invention is not limited to this. For example, the area of ​​subpixel R may be smaller than the areas of subpixels G and B. As described above, the area of ​​a subpixel having a light-emitting device may be determined depending on the lifespan of the light-emitting device of each color.

[0404] A variation of FIG. 23A is shown in FIGS. 25A and 25B.

[0405] 25A , the display section of the display device employs a first array ARR1 in which subpixels 110b, 110a, 110b, and 110c are repeatedly arranged in this order in the row direction, and a second array ARR2 in which subpixels 110d, 110a, 110d, and 110c are repeatedly arranged in this order in the row direction. Furthermore, the first array ARR1 and the second array ARR2 are repeatedly arranged alternately in the column direction.

[0406] The display unit has a third array ARR3 in which the sub-pixels 110b, 110d, and 110a are repeatedly arranged in this order in the column direction, and a fourth array ARR4 in which the sub-pixels 110b, 110d, and 110c are repeatedly arranged in this order in the column direction.Furthermore, the third array ARR3, the third array ARR3, the fourth array ARR4, and the fourth array ARR4 are repeatedly arranged in this order in the row direction.

[0407] 25B , the display portion of the display device employing the pixel layout shown in FIG. 25B includes a first array ARR1 in which subpixels 110b, 110a, 110d, and 110a are repeatedly arranged in this order in the row direction, a second array ARR2 in which subpixels 110d, 110a, 110b, and 110c are repeatedly arranged in this order in the row direction, a third array ARR3 in which subpixels 110b, 110c, 110d, and 110c are repeatedly arranged in this order in the row direction, and a fourth array ARR4 in which subpixels 110d, 110c, 110b, and 110a are repeatedly arranged in this order in the row direction. Furthermore, the first array ARR1, the second array ARR2, the third array ARR3, and the fourth array ARR4 are repeatedly arranged in this order in the column direction.

[0408] The display unit has a fifth array ARR5 in which the sub-pixels 110b and 110d are alternately arranged in the column direction, and a sixth array ARR6 in which the sub-pixels 110a and 110c are alternately arranged in the column direction. Furthermore, the fifth array ARR5 and the sixth array ARR6 are alternately arranged in the row direction.

[0409] 26A and 26B show an example configuration in which a sub-pixel R having a function of emitting red light is applied to the sub-pixel 110a shown in FIG. 25A and FIG. 25B, a sub-pixel G having a function of emitting green light is applied to the sub-pixel 110b, a sub-pixel B having a function of emitting blue light is applied to the sub-pixel 110c, and a sub-pixel PS having a light-receiving function is applied to the sub-pixel 110d.

[0410] 26A has a first array ARR1 in which subpixels G, R, G, and B are repeatedly arranged in this order in the row direction, and a second array ARR2 in which subpixels PS, R, PS, and B are repeatedly arranged in this order in the row direction. Furthermore, the first array ARR1 and the second array ARR2 are repeatedly arranged alternately in the column direction.

[0411] The display unit has a third array ARR3 in which subpixels G, PS, and R are repeatedly arranged in this order in the column direction, and a fourth array ARR4 in which subpixels G, PS, and B are repeatedly arranged in this order in the column direction.Furthermore, the third array ARR3, the third array ARR3, the fourth array ARR4, and the fourth array ARR4 are repeatedly arranged in this order in the row direction.

[0412] The display unit of the display device to which the pixel layout shown in FIG. 26B is applied has a first array ARR1 in which sub-pixels G, sub-pixels R, sub-pixels PS, and sub-pixels R are repeatedly arranged in this order in the row direction, a second array ARR2 in which sub-pixels PS, sub-pixels R, sub-pixels G, and sub-pixels B are repeatedly arranged in this order in the row direction, a third array ARR3 in which sub-pixels G, sub-pixels B, sub-pixels PS, and sub-pixels B are repeatedly arranged in this order in the row direction, and a fourth array ARR4 in which sub-pixels PS, sub-pixels B, sub-pixels G, and sub-pixels R are repeatedly arranged in this order in the row direction. Further, in the column direction, the first array ARR1, the second array ARR2, the third array ARR3, and the fourth array ARR4 are repeatedly arranged in this order.

[0413] The display unit has a fifth array ARR5 in which sub-pixels G and sub-pixels PS are repeatedly arranged alternately in the column direction, and a sixth array ARR6 in which sub-pixels R and sub-pixels B are repeatedly arranged alternately in the column direction. Further, in the row direction, the fifth array ARR5 and the sixth array ARR6 are repeatedly arranged alternately.

[0414] A modified example of FIG. 26A is shown in FIG. 27A. The configuration shown in FIG. 27A is mainly different from the configuration shown in FIG. 26A in that the upper surface shape of the sub-pixels is different.

[0415] The display unit of the display device to which the pixel layout shown in FIG. 27A is applied has a first array ARR1 in which sub-pixels 110b, sub-pixels 110a, sub-pixels 110b, and sub-pixels 110c are repeatedly arranged in this order in the row direction, and a second array ARR2 in which sub-pixels 110d, sub-pixels 110a, sub-pixels 110d, and sub-pixels 110c are repeatedly arranged in this order in the row direction. Further, in the column direction, the first array ARR1 and the second array ARR2 are repeatedly arranged alternately. Further, the display unit may have a third array ARR3 in which sub-pixels 110a and sub-pixels 110c are repeatedly arranged alternately in the row direction.

[0416] The display unit has a fourth array ARR4 in which the subpixels 110b and 110d are alternately arranged in the column direction, and a fifth array ARR5 in which the subpixels 110a and 110c are alternately arranged in the column direction. Furthermore, the fourth array ARR4 and the fifth array ARR5 are alternately arranged in the row direction. The display unit may also have a sixth array ARR6 in which the subpixels 110b, 110a, 110d, 110b, 110c, and 110d are alternately arranged in the column direction.

[0417] 27A shows a configuration in which the top surfaces of the subpixels 110a and 110c are rectangular with rounded corners and the top surfaces of the subpixels 110b and 110d are triangular with rounded corners, but the top surface shapes of the subpixels are not particularly limited. For example, the top surfaces of the subpixels 110b and 110d may be rectangular with rounded corners or may be circular. Furthermore, the top surface shapes of the subpixels may differ.

[0418] Figure 27B shows an example configuration in which subpixel R having the function of emitting red light is applied to subpixel 110a shown in Figure 27A, subpixel G having the function of emitting green light is applied to subpixel 110b, subpixel B having the function of emitting blue light is applied to subpixel 110c, and subpixel PS having a light-receiving function is applied to subpixel 110d.

[0419] 27B has a first array ARR1 in which subpixels G, R, G, and B are repeatedly arranged in this order in the row direction, and a second array ARR2 in which subpixels PS, R, PS, and B are repeatedly arranged in this order in the row direction. The display unit may also have a third array ARR3 in which subpixels R and B are repeatedly arranged alternately in the row direction.

[0420] The display unit has a fourth array ARR4 in which subpixel G, subpixel R, subpixel PS, subpixel G, subpixel B, and subpixel PS are repeatedly arranged in this order in the column direction. The display unit may have a fifth array ARR5 in which subpixels R and B are repeatedly arranged alternately in the column direction, or a sixth array ARR6 in which subpixels G and subpixels PS are repeatedly arranged alternately in the column direction.

[0421] <Configuration Example 2 of Display Device> A configuration example different from the above-described display device 100 is shown in FIGS. 28A and 28B.

[0422] Fig. 28A is a top view of the display device 100A. Fig. 28B shows a cross-sectional view taken along dashed dotted line X3-X4 in Fig. 28A. The display device 100A is an example in which the arrangement of pixels 110 shown in Fig. 21I is applied.

[0423] <Example of Manufacturing Method of Display Device> Next, an example of a manufacturing method of a display device will be described with reference to FIGS. 29 to 38. FIGS. 29A to 29F are top views illustrating a manufacturing method of the display device 100 shown in FIGS. 20A and 20B. FIGS. 30A to 30C show a cross-sectional view taken along dashed dotted line X1-X2 in FIG. 20A and a cross-sectional view taken along dashed dotted line Y1-Y2 side by side. FIGS. 31 to 36 and 37A are similar to FIG. 30. FIGS. 37B to 37D show a cross-sectional view taken along dashed dotted line X1-X2 in FIG. 20A. FIG. 37E shows a cross-sectional view taken along dashed dotted line Y1-Y2 in FIG. 20A. FIGS. 38A to 38F show enlarged views illustrating the cross-sectional structure of the insulating layer 127 and its surroundings.

[0424] Thin films (insulating films, semiconductor films, conductive films, etc.) constituting display devices can be formed using a sputtering method, a chemical vapor deposition (CVD) method, a vacuum evaporation method, a pulsed laser deposition (PLD) method, an ALD method, etc. CVD methods include a plasma enhanced chemical vapor deposition (PECVD) method and a thermal CVD method. One type of thermal CVD method is a metal organic chemical vapor deposition (MOCVD) method.

[0425] Thin films (insulating films, semiconductor films, conductive films, etc.) that constitute the display device can be formed by methods such as spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, doctor knife, slit coating, roll coating, curtain coating, and knife coating.

[0426] In particular, vacuum processes such as vapor deposition and solution processes such as spin coating and inkjet printing can be used to fabricate light-emitting devices. Vapor deposition methods include physical vapor deposition (PVD) methods such as sputtering, ion plating, ion beam deposition, molecular beam deposition, and vacuum deposition, and chemical vapor deposition (CVD). In particular, functional layers included in the EL layer (hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, etc.) can be formed by vapor deposition (vacuum deposition, etc.), coating methods (dip coating, die coating, bar coating, spin coating, spray coating, etc.), printing methods (inkjet printing, screen (stencil printing), offset (lithographic printing), flexography (relief printing), gravure, microcontact printing, etc.), etc.

[0427] When processing the thin film that constitutes the display device, a photolithography method or the like can be used. Alternatively, the thin film may be processed by a nanoimprint method, a sandblasting method, a lift-off method, or the like. Furthermore, the island-shaped thin film may be directly formed by a film formation method using a shielding mask such as a metal mask.

[0428] There are two typical photolithography methods: one is to form a resist mask on the thin film to be processed, process the thin film by etching or the like, and then remove the resist mask; the other is to form a photosensitive thin film, and then process the thin film into the desired shape by exposure and development.

[0429] In photolithography, the light used for exposure may be, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or a mixture of these. Other light sources that can be used include ultraviolet light, KrF laser light, ArF laser light, etc. Exposure may also be performed by immersion exposure technology. Extreme ultraviolet (EUV) light or X-rays may also be used as the light used for exposure. An electron beam may also be used instead of the light used for exposure. Extreme ultraviolet light, X-rays, or an electron beam are preferred because they enable extremely fine processing. When exposure is performed by scanning a beam such as an electron beam, a photomask is not required.

[0430] For etching the thin film, dry etching, wet etching, sandblasting, or the like can be used.

[0431] First, as shown in FIG. 30A, a conductive film 111 is formed over a layer 101 including a transistor.

[0432] Then, a first layer 113A is formed over the conductive film 111, a first sacrificial layer 118A is formed over the first layer 113A, and a second sacrificial layer 119A is formed over the first sacrificial layer 118A.

[0433] 30A , in the cross-sectional view between Y1 and Y2, the end of the first layer 113A on the connection portion 140 side is located inside the end of the first sacrificial layer 118A. For example, by using a mask for defining the film formation area (also called an area mask or a rough metal mask to distinguish it from a fine metal mask), it is possible to vary the regions where the first layer 113A, the first sacrificial layer 118A, and the second sacrificial layer 119A are formed. In one embodiment of the present invention, a light-emitting device is formed using a resist mask. However, by combining the resist mask with an area mask as described above, a light-emitting device can be manufactured by a relatively simple process.

[0434] The conductive film 111 is a layer that will be processed later to become the pixel electrodes 111a, 111b, and 111c and the conductive layer 123. Therefore, the structure applicable to the pixel electrodes described above can be applied to the conductive film 111. The conductive film 111 can be formed by, for example, sputtering or vacuum evaporation.

[0435] The first layer 113A is a layer that will later become the EL layer 113a. Therefore, the above-described structure applicable to the EL layer 113a can be used. The first layer 113A can be formed by a method such as a vapor deposition method (including a vacuum deposition method), a transfer method, a printing method, an inkjet method, or a coating method. The first layer 113A is preferably formed by a vapor deposition method. When forming a film using a vapor deposition method, a premix material may be used. Note that in this specification and the like, a premix material is a composite material in which multiple materials are blended or mixed in advance.

[0436] The first sacrificial layer 118A and the second sacrificial layer 119A are made of a film that is highly resistant to the processing conditions of the first layer 113A and the second layer 113B and third layer 113C that will be formed in later steps, specifically, a film that has a large etching selectivity with respect to various EL layers.

[0437] The first sacrificial layer 118A and the second sacrificial layer 119A can be formed by, for example, sputtering, ALD (including thermal ALD and PEALD), CVD, or vacuum evaporation. The first sacrificial layer 118A, which is formed on and in contact with the EL layer, is preferably formed using a method that causes less damage to the EL layer than the second sacrificial layer 119A. For example, the first sacrificial layer 118A is preferably formed using ALD or vacuum evaporation rather than sputtering. The first sacrificial layer 118A and the second sacrificial layer 119A are formed at a temperature lower than the heat-resistant temperature limit of the EL layer (typically, 200° C. or lower, preferably 100° C. or lower, and more preferably 80° C. or lower).

[0438] It is preferable to use a film that can be removed by wet etching for the first sacrificial layer 118A and the second sacrificial layer 119A, since wet etching can reduce damage to the first layer 113A during processing of the first sacrificial layer 118A and the second sacrificial layer 119A compared to dry etching.

[0439] It is preferable to use a film having a large etching selectivity with respect to the second sacrificial layer 119A for the first sacrificial layer 118A.

[0440] In the process of processing the various sacrificial layers in the manufacturing method of the display device of this embodiment, it is desirable that the layers constituting the EL layer (such as the hole injection layer, the hole transport layer, the light-emitting layer, and the electron transport layer) are not easily processed, and that the various sacrificial layers are not easily processed in the process of processing the layers constituting the EL layer. It is desirable to select the material and processing method of the sacrificial layer and the processing method of the EL layer taking these factors into consideration.

[0441] In this embodiment, an example is shown in which the sacrificial layer is formed with a two-layer structure of a first sacrificial layer and a second sacrificial layer, but the sacrificial layer may have a single-layer structure or a stacked structure of three or more layers.

[0442] The first sacrificial layer 118A and the second sacrificial layer 119A can each be made of an inorganic film such as a metal film, an alloy film, a metal oxide film, a semiconductor film, or an inorganic insulating film.

[0443] The first sacrificial layer 118A and the second sacrificial layer 119A can be made of a metal material such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, or tantalum, or an alloy material containing such a metal material. In particular, it is preferable to use a low-melting-point material such as aluminum or silver. Using a metal material capable of blocking ultraviolet light for one or both of the first sacrificial layer 118A and the second sacrificial layer 119A can prevent the EL layer from being exposed to ultraviolet light, thereby suppressing deterioration of the EL layer.

[0444] The first sacrificial layer 118A and the second sacrificial layer 119A can be made of a metal oxide such as In—Ga—Zn oxide. For example, an In—Ga—Zn oxide film can be formed as the first sacrificial layer 118A or the second sacrificial layer 119A by sputtering. Furthermore, indium oxide, In—Zn oxide, In—Sn oxide, indium titanium oxide (In—Ti oxide), indium tin zinc oxide (In—Sn—Zn oxide), indium titanium zinc oxide (In—Ti—Zn oxide), indium gallium tin zinc oxide (In—Ga—Sn—Zn oxide), or the like can be used. Alternatively, indium tin oxide containing silicon can also be used.

[0445] Instead of the gallium, an element M (wherein M is one or more elements selected from aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium) may be used. In particular, it is preferable that M is one or more elements selected from gallium, aluminum, and yttrium.

[0446] The first sacrificial layer 118A and the second sacrificial layer 119A can be made of any of the various inorganic insulating films that can be used for the protective layers 131 and 132. In particular, oxide insulating films are preferable because they have higher adhesion to the EL layer than nitride insulating films. For example, inorganic insulating materials such as aluminum oxide, hafnium oxide, and silicon oxide can be used for the first sacrificial layer 118A and the second sacrificial layer 119A. For example, an aluminum oxide film can be formed as the first sacrificial layer 118A or the second sacrificial layer 119A by the ALD method. The ALD method is preferable because it can reduce damage to the underlying layer (particularly the EL layer, etc.).

[0447] For example, an inorganic insulating film (e.g., an aluminum oxide film) formed by ALD can be used as the first sacrificial layer 118A, and an In—Ga—Zn oxide film formed by sputtering can be used as the second sacrificial layer 119A. Alternatively, an aluminum film or a tungsten film can be used as the second sacrificial layer 119A.

[0448] The first sacrificial layer 118A and the second sacrificial layer 119A may be made of a material that is soluble in a chemically stable solvent, at least for the film located at the top of the first layer 113A. In particular, materials that dissolve in water or alcohol are suitable for use as the first sacrificial layer 118A or the second sacrificial layer 119A. When forming a film of such a material, it is preferable to apply the material dissolved in a solvent such as water or alcohol by a wet film formation method, and then perform a heat treatment to evaporate the solvent. In this case, 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 EL layer.

[0449] The first sacrificial layer 118A and the second sacrificial layer 119A may be formed using a wet film formation method such as spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, or knife coating.

[0450] The first sacrificial layer 118A and the second sacrificial layer 119A may be made of an organic material such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin.

[0451] 30B, a resist mask 190a is formed on the second sacrificial layer 119A. The resist mask can be formed by applying a photosensitive resin (photoresist) and then performing exposure and development.

[0452] The resist mask may be made of either a positive resist material or a negative resist material.

[0453] 29A , the resist mask 190a is provided in a position that overlaps with an area that will later become the sub-pixel 110a. It is preferable that the resist mask 190a has an island-shaped pattern for each sub-pixel 110a. Alternatively, the resist mask 190a may have a strip-shaped pattern for multiple sub-pixels 110a that are aligned in a line (aligned in the Y direction in FIG. 29A ).

[0454] Note that the resist mask 190a is preferably provided also in a position overlapping with a region that will later become the connection portion 140 (see FIGS. 29A and 30B ). This can prevent the region of the conductive film 111 that will later become the conductive layer 123 from being damaged during the manufacturing process of the display device.

[0455] 30C , a resist mask 190a is used to remove a portion of the second sacrificial layer 119A to form a second sacrificial layer 119a. The second sacrificial layer 119a remains in the region that will later become the subpixel 110a and the region that will later become the connection portion 140.

[0456] When etching the second sacrificial layer 119A, it is preferable to use etching conditions with a high selectivity so that the first sacrificial layer 118A is not removed by the etching. Furthermore, since the EL layer is not exposed when processing the second sacrificial layer 119A, the range of processing methods available is wider than when processing the first sacrificial layer 118A. Specifically, even when a gas containing oxygen is used as an etching gas when processing the second sacrificial layer 119A, deterioration of the EL layer can be further suppressed.

[0457] Thereafter, the resist mask 190a is removed. For example, the resist mask 190a can be removed by ashing using oxygen plasma. Alternatively, the resist mask 190a may be removed by wet etching. At this time, the first sacrificial layer 118A is located on the outermost surface and the first layer 113A is not exposed, so that damage to the first layer 113A can be suppressed in the process of removing the resist mask 190a. Furthermore, the range of options for removing the resist mask 190a can be expanded.

[0458] Next, as shown in FIG. 31A, the second sacrificial layer 119a is used as a hard mask to remove a portion of the first sacrificial layer 118A, thereby forming a first sacrificial layer 118a.

[0459] The first sacrificial layer 118A and the second sacrificial layer 119A can be processed by wet etching or dry etching, respectively. The first sacrificial layer 118A and the second sacrificial layer 119A are preferably processed by anisotropic etching.

[0460] Compared to the case of using dry etching, the use of wet etching can reduce damage to the first layer 113A during processing of the first sacrificial layer 118A and the second sacrificial layer 119A. When using wet etching, it is preferable to use a chemical solution such as a developer, a tetramethylammonium hydroxide (TMAH) aqueous solution, dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or a mixture thereof.

[0461] When dry etching is used, deterioration of the first layer 113A can be suppressed by not using a gas containing oxygen as an etching gas. ４ , C ４ F ８ , SF ６ , CHF ３ , Cl ２ , H ２ O, BCl ３ It is preferable to use a gas containing a noble gas (also called a rare gas) such as He as the etching gas.

[0462] For example, when an aluminum oxide film formed by ALD is used as the first sacrificial layer 118A, CHF ３ The first sacrificial layer 118A can be processed by dry etching using He. When an In—Ga—Zn oxide film formed by sputtering is used as the second sacrificial layer 119A, the second sacrificial layer 119A can be processed by wet etching using diluted phosphoric acid.

[0463] Next, as shown in FIG. 31B, the second sacrificial layer 119a and the first sacrificial layer 118a are used as a hard mask to remove a portion of the first layer 113A, thereby forming an EL layer 113a.

[0464] 31B , in the region corresponding to the subpixel 110a, a stacked structure of the EL layer 113a, the first sacrificial layer 118a, and the second sacrificial layer 119a remains on the conductive film 111. In addition, in the region corresponding to the connection portion 140, a stacked structure of the first sacrificial layer 118a and the second sacrificial layer 119a remains on the conductive film 111.

[0465] Through the above steps, regions of the first layer 113A, the first sacrificial layer 118A, and the second sacrificial layer 119A that do not overlap with the resist mask 190a can be removed.

[0466] Note that a part of the first layer 113A may be removed using the resist mask 190a, and then the resist mask 190a may be removed.

[0467] Alternatively, the process may proceed to the next step without removing the resist mask 190a. In this case, when processing the conductive film 111 in a later step, not only the sacrificial layer but also the resist mask can be used as a mask. Processing the conductive film 111 using the resist masks 190a, 190b, and 190c may make the conductive film 111 easier to process than when only the sacrificial layer is used as a hard mask. For example, the range of options for the processing conditions of the conductive film 111, the material of the sacrificial layer, or the material of the conductive film can be expanded.

[0468] The first layer 113A is preferably processed by anisotropic etching, particularly anisotropic dry etching, or wet etching.

[0469] When dry etching is used, deterioration of the first layer 113A can be suppressed by not using a gas containing oxygen as an etching gas.

[0470] A gas containing oxygen may be used as the etching gas. When the etching gas contains oxygen, the etching rate can be increased. Therefore, etching can be performed under low power conditions while maintaining a sufficiently high etching rate. This can suppress damage to the first layer 113A. Furthermore, problems such as adhesion of reaction products generated during etching can be suppressed.

[0471] When dry etching is used, for example, H ２ , C.F. ４ , C ４ F ８ , SF ６ , CHF ３ , Cl ２ , H ２ O, BCl ３ It is preferable to use a gas containing one or more of the noble gases such as He and Ar as the etching gas. Alternatively, it is preferable to use a gas containing one or more of these and oxygen as the etching gas. Alternatively, oxygen gas may be used as the etching gas. Specifically, for example, H ２ and a gas containing Ar, or CF ４ A gas containing CF and He can be used as an etching gas. ４ A gas containing He and oxygen can be used as the etching gas.

[0472] Next, as shown in FIG. 31C, a second layer 113B is formed on the second sacrificial layer 119a and the conductive film 111, a first sacrificial layer 118B is formed on the second layer 113B, and a second sacrificial layer 119B is formed on the first sacrificial layer 118B.

[0473] As shown in FIG. 31C, in the cross section taken along line Y1-Y2, the end of second layer 113B on the connection section 140 side is located more inward than the end of first sacrificial layer 118B.

[0474] The second layer 113B is a layer that will later become the EL layer 113b. The EL layer 113b emits light in a wavelength region different from that of the EL layer 113a. The configuration, materials, etc. that can be applied to the EL layer 113b are the same as those of the EL layer 113a. The second layer 113B can be formed using a method similar to that for the first layer 113A.

[0475] The first sacrificial layer 118B can be formed using a material that can be used for the first sacrificial layer 118A. The second sacrificial layer 119B can be formed using a material that can be used for the second sacrificial layer 119A.

[0476] Next, as shown in FIG. 31C, a resist mask 190b is formed on the second sacrificial layer 119B.

[0477] 29B , the resist mask 190b is provided in a position that overlaps with an area that will later become the sub-pixel 110b. Preferably, the resist mask 190b has an island-shaped pattern for each sub-pixel 110b. Alternatively, the resist mask 190b may have a strip-shaped pattern for a plurality of sub-pixels 110b that are arranged in a row.

[0478] The resist mask 190b may also be provided at a position that overlaps with the region that will later become the connection portion 140.

[0479] Next, a resist mask 190b is used to remove a portion of the second sacrificial layer 119B to form a second sacrificial layer 119b, which remains in the region that will later become the sub-pixel 110b.

[0480] Thereafter, the resist mask 190b is removed, and then, using the second sacrificial layer 119b as a hard mask, a part of the first sacrificial layer 118B is removed to form a first sacrificial layer 118b.

[0481] Then, as shown in FIG. 32A, the second sacrificial layer 119b and the first sacrificial layer 118b are used as a hard mask to remove a portion of the second layer 113B, thereby forming an EL layer 113b.

[0482] 32A , in a region corresponding to the subpixel 110b, a stacked structure of the EL layer 113b, the first sacrificial layer 118b, and the second sacrificial layer 119b remains on the conductive film 111. In addition, in a region corresponding to the connection portion 140, a stacked structure of the first sacrificial layer 118a and the second sacrificial layer 119a remains on the conductive film 111.

[0483] Through the above steps, regions of the second layer 113B, the first sacrificial layer 118B, and the second sacrificial layer 119B that do not overlap with the resist mask 190b can be removed. These layers can be processed using a method that can be applied to processing the first layer 113A, the first sacrificial layer 118A, and the second sacrificial layer 119A.

[0484] Next, as shown in FIG. 32B, a third layer 113C is formed on the second sacrificial layer 119a, the second sacrificial layer 119b, and the conductive film 111, a first sacrificial layer 118C is formed on the third layer 113C, and a second sacrificial layer 119C is formed on the first sacrificial layer 118C.

[0485] As shown in FIG. 32B, in the cross-sectional view taken along line Y1-Y2, the end of the third layer 113C on the connection section 140 side is located more inward than the end of the first sacrificial layer 118C.

[0486] The third layer 113C is a layer that will later become the EL layer 113c. The EL layer 113c emits light in a wavelength region different from that of the EL layers 113a and 113b. The structure, materials, and the like that can be applied to the EL layer 113c are the same as those of the EL layer 113a. The third layer 113C can be formed using a method similar to that for the first layer 113A.

[0487] The first sacrificial layer 118C can be formed using a material that can be used for the first sacrificial layer 118A. The second sacrificial layer 119C can be formed using a material that can be used for the second sacrificial layer 119A.

[0488] Next, as shown in FIG. 32B, a resist mask 190c is formed on the second sacrificial layer 119C.

[0489] 29C , the resist mask 190c is provided in a position that overlaps with an area that will later become the sub-pixel 110c. Preferably, the resist mask 190c has an island-shaped pattern for each sub-pixel 110c. Alternatively, the resist mask 190c may have a strip-shaped pattern for a plurality of sub-pixels 110c arranged in a row.

[0490] The resist mask 190c may also be provided at a position that overlaps with the region that will later become the connection section 140.

[0491] Next, a resist mask 190c is used to remove a portion of the second sacrificial layer 119C to form a second sacrificial layer 119c, which remains in a region that will later become the sub-pixel 110c.

[0492] Thereafter, the resist mask 190c is removed. Then, using the second sacrificial layer 119c as a hard mask, a part of the first sacrificial layer 118C is removed to form a first sacrificial layer 118c.

[0493] Then, as shown in FIG. 32C, the second sacrificial layer 119c and the first sacrificial layer 118c are used as a hard mask to remove a portion of the third layer 113C, thereby forming an EL layer 113c.

[0494] 32C , in a region corresponding to the subpixel 110c, a stacked structure of the EL layer 113c, the first sacrificial layer 118c, and the second sacrificial layer 119c remains on the conductive film 111. In addition, in a region corresponding to the connection portion 140, a stacked structure of the first sacrificial layer 118a and the second sacrificial layer 119a remains on the conductive film 111.

[0495] Through the above steps, regions of the third layer 113C, the first sacrificial layer 118C, and the second sacrificial layer 119C that are not overlapped with the resist mask 190c can be removed. These layers can be processed using a method that can be applied to processing the first layer 113A, the first sacrificial layer 118A, and the second sacrificial layer 119A.

[0496] Next, as shown in FIG. 33A, a fourth layer 113D is formed on the second sacrificial layer 119a, the second sacrificial layer 119b, the second sacrificial layer 119c, and the conductive film 111, a first sacrificial layer 118D is formed on the fourth layer 113D, and a second sacrificial layer 119D is formed on the first sacrificial layer 118D.

[0497] As shown in FIG. 33A, in the cross-sectional view taken along line Y1-Y2, the end of the fourth layer 113D on the connection section 140 side is located more inward than the end of the first sacrificial layer 118D.

[0498] The fourth layer 113D is a layer that will later become the light-receiving layer 113d. The light-receiving layer 113d has an active layer. The fourth layer 113D can be formed using a method similar to that for the first layer 113A.

[0499] The first sacrificial layer 118D can be formed using a material that can be used for the first sacrificial layer 118A. The second sacrificial layer 119D can be formed using a material that can be used for the second sacrificial layer 119A.

[0500] Next, as shown in FIG. 33A, a resist mask 190d is formed on the second sacrificial layer 119D.

[0501] 29D , the resist mask 190d is provided in a position that overlaps with an area that will later become the sub-pixel 110d. It is preferable that the resist mask 190d has an island-shaped pattern for each sub-pixel 110d. Alternatively, the resist mask 190d may have a strip-shaped pattern for a plurality of sub-pixels 110d that are arranged in a row.

[0502] The resist mask 190d may also be provided at a position that overlaps with the region that will later become the connection section 140.

[0503] Next, a resist mask 190d is used to remove a portion of the second sacrificial layer 119D to form a second sacrificial layer 119d, which remains in a region that will later become the sub-pixel 110d.

[0504] Thereafter, the resist mask 190d is removed, and then, using the second sacrificial layer 119d as a hard mask, a portion of the first sacrificial layer 118D is removed to form a first sacrificial layer 118d.

[0505] Then, as shown in FIG. 33B, second sacrificial layer 119d and first sacrificial layer 118d are used as a hard mask to remove a portion of fourth layer 113D, thereby forming light-receiving layer 113d.

[0506] 33B , in the region corresponding to the subpixel 110d, a layered structure of the light-receiving layer 113d, the first sacrificial layer 118d, and the second sacrificial layer 119d remains on the conductive film 111. In addition, in the region corresponding to the connection portion 140, a layered structure of the first sacrificial layer 118a and the second sacrificial layer 119a remains on the conductive film 111.

[0507] Through the above steps, regions of the fourth layer 113D, the first sacrificial layer 118D, and the second sacrificial layer 119D that are not overlapped with the resist mask 190d can be removed. These layers can be processed using a method that can be applied to processing the first layer 113A, the first sacrificial layer 118A, and the second sacrificial layer 119A.

[0508] The side surfaces of the EL layer 113 a, the EL layer 113 b, the EL layer 113 c, and the light-receiving layer 113 d are preferably perpendicular or approximately perpendicular to the surface on which they are formed. For example, the angle between the surface on which they are formed and these side surfaces is preferably 60 degrees or more and 90 degrees or less.

[0509] Next, as shown in FIG. 34A , the conductive film 111 is processed using the first sacrificial layer 118 a, the first sacrificial layer 118 b, the first sacrificial layer 118 c, the first sacrificial layer 118 d, the second sacrificial layer 119 a, the second sacrificial layer 119 b, the second sacrificial layer 119 c, and the second sacrificial layer 119 d as hard masks to form the pixel electrode 111 a, the pixel electrode 111 b, the pixel electrode 111 c, the pixel electrode 111 d, and the conductive layer 123.

[0510] When the conductive film 111 is processed, a part of the transistor-including layer 101 (specifically, the insulating layer located at the outermost surface) may be processed to form a recess. In the following description, a case where a recess is provided in the transistor-including layer 101 will be described as an example, but the recess may not be provided.

[0511] Here, in order to form the conductive layer 123, it is preferable that any one of the first sacrificial layer 118a, the first sacrificial layer 118b, the first sacrificial layer 118c, and the first sacrificial layer 118d and any one of the second sacrificial layer 119a, the second sacrificial layer 119b, the second sacrificial layer 119c, and the second sacrificial layer 119d be provided in the connection portion 140. Any two or all of the first sacrificial layer 118a, the first sacrificial layer 118b, the first sacrificial layer 118c, and the first sacrificial layer 118d and any two or all of the second sacrificial layer 119a, the second sacrificial layer 119b, the second sacrificial layer 119c, and the second sacrificial layer 119d be provided in the connection portion 140. By providing the sacrificial layer in the connection portion 140, a region of the conductive film 111 that becomes the conductive layer 123 can be prevented from being damaged during the manufacturing process of the display device. Therefore, it is preferable to form the first sacrificial layer 118 a and the second sacrificial layer 119 a in the connection section 140 , as these layers are manufactured in the shortest time.

[0512] A wet etching method or a dry etching method can be used to process the conductive film 111. The conductive film 111 is preferably processed by anisotropic etching.

[0513] Next, as shown in FIG. 34B , an insulating film 125A is formed so as to cover the pixel electrode 111a, the pixel electrode 111b, the pixel electrode 111c, the pixel electrode 111d, the EL layer 113a, the EL layer 113b, the EL layer 113c, the light-receiving layer 113d, the first sacrificial layer 118a, the first sacrificial layer 118b, the first sacrificial layer 118c, the first sacrificial layer 118d, the second sacrificial layer 119a, the second sacrificial layer 119b, the second sacrificial layer 119c, and the second sacrificial layer 119d.

[0514] The insulating film 125A can be, for example, an inorganic insulating film such as an oxide insulating film, a nitride insulating film, an oxynitride insulating film, or a nitride oxide insulating film. Examples of oxide insulating films include a silicon oxide film, an aluminum oxide film, a magnesium oxide film, a gallium oxide film, a germanium oxide film, an yttrium oxide film, a zirconium oxide film, a lanthanum oxide film, a neodymium oxide film, a hafnium oxide film, and a tantalum oxide film. Examples of nitride insulating films include a silicon nitride film and an aluminum nitride film. Examples of oxynitride insulating films include a silicon oxynitride film and an aluminum oxynitride film. Examples of nitride oxide insulating films include a silicon nitride oxide film and an aluminum nitride oxide film. Metal oxide films such as an indium gallium zinc oxide film may also be used.

[0515] The insulating film 125A preferably functions as a barrier insulating film against at least one of water and oxygen, or preferably has a function of suppressing diffusion of at least one of water and oxygen, or preferably has a function of capturing or fixing (also referred to as gettering) at least one of water and oxygen.

[0516] In this specification and the like, a barrier insulating film refers to an insulating film having barrier properties. Furthermore, in this specification and the like, the term "barrier properties" refers to a function of suppressing the diffusion of a corresponding substance (also referred to as low permeability), or a function of capturing or fixing a corresponding substance (also referred to as gettering).

[0517] The insulating film 125A has the above-mentioned barrier insulating film function or gettering function, which makes it possible to suppress the intrusion of impurities (typically water or oxygen) that can diffuse into each light-emitting device from the outside. With this configuration, it is possible to provide a display device with excellent reliability.

[0518] Next, as shown in FIG. 34C, an insulating film 127A is formed on the insulating film 125A.

[0519] 29E, the insulating film 127A is preferably formed so as to have an opening at a position overlapping the conductive layer 123 (connection portion 140). The insulating film 127A can be patterned by, for example, applying a photosensitive resin and then performing exposure and development.

[0520] As shown in FIG. 37A, the insulating film 127A may be formed so as to have openings at positions overlapping with the pixel electrodes 111a, 111b, 111c, and 111d.

[0521] The insulating film 127A can be made of an organic material. Examples of organic materials include acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, and precursors of these resins. The insulating film 127A can also be made of an organic material such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin. The insulating film 127A can also be made of a photosensitive resin. Photoresist can be used as the photosensitive resin. The photosensitive resin can be a positive-type material or a negative-type material.

[0522] The method for forming the insulating film 127A is not particularly limited, and the insulating film 127A can be formed using a wet film formation method such as spin coating, dipping, spray coating, inkjet printing, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, or knife coating. In particular, it is preferable to form the insulating film 127A by spin coating.

[0523] The insulating films 125A and 127A are preferably formed by a method that causes less damage to the EL layer. In particular, since the insulating film 125A is formed in contact with the side surface of the EL layer, it is preferably formed by a method that causes less damage to the EL layer than the insulating film 127A. Furthermore, the insulating films 125A and 127A are each formed at a temperature lower than the heat resistance temperature of the EL layer (typically 200° C. or lower, preferably 100° C. or lower, and more preferably 80° C. or lower). For example, an aluminum oxide film can be formed as the insulating film 125A by an ALD method. The ALD method is preferable because it can reduce film formation damage and form a film with high coverage.

[0524] Next, as shown in FIG. 35A , insulating layers 125 and 127 are formed by processing insulating films 125A and 127A. Insulating layer 127 is formed so as to contact the side surfaces of insulating layer 125 and the upper surface of the recess. Insulating layer 125 (and further insulating layer 127) are provided so as to cover the side surfaces of pixel electrode 111a, pixel electrode 111b, pixel electrode 111c, and pixel electrode 111d. This prevents a short circuit in the light-emitting device caused by contact between a film (such as a film constituting the EL layer, a film constituting the light-receiving layer, or a common electrode) and pixel electrode 111a, pixel electrode 111b, pixel electrode 111c, or pixel electrode 111d to be formed later. Furthermore, insulating layers 125 and 127 are preferably provided so as to cover the side surfaces of EL layer 113a, EL layer 113b, EL layer 113c, and light-receiving layer 113d. This prevents films to be formed later from coming into contact with the side surfaces of these layers, thereby preventing the light-emitting device from shorting out, and also prevents damage to the EL layers 113 a, 113 b, 113 c, and the light-receiving layer 113 d in later steps.

[0525] In particular, if a recess is provided in a part of the layer 101 including the transistor (specifically, the insulating layer located on the outermost surface), it is possible to cover the entire side surfaces of the pixel electrodes 111a, 111b, 111c, and 111d with the insulating layers 125 and 127, which is preferable.

[0526] The insulating film 125A is preferably processed by dry etching. The insulating film 125A is preferably processed by anisotropic etching. The insulating film 125A can be processed using an etching gas that can be used to process the first sacrificial layer 118A and the second sacrificial layer 119A.

[0527] The insulating film 127A is preferably processed by ashing using oxygen plasma, for example.

[0528] 35B , the first sacrificial layer 118a, the first sacrificial layer 118b, the first sacrificial layer 118c, the first sacrificial layer 118d, the second sacrificial layer 119a, the second sacrificial layer 119b, the second sacrificial layer 119c, and the second sacrificial layer 119d are removed, thereby exposing the EL layer 113a on the pixel electrode 111a, the EL layer 113b on the pixel electrode 111b, the EL layer 113c on the pixel electrode 111c, the light-receiving layer 113d on the pixel electrode 111d, and the conductive layer 123 at the connection portion 140. Note that a portion of the first sacrificial layer 118 a, the first sacrificial layer 118 b, the first sacrificial layer 118 c, the first sacrificial layer 118 d, the second sacrificial layer 119 a, the second sacrificial layer 119 b, the second sacrificial layer 119 c, or the second sacrificial layer 119 d may remain. For example, in the connection portion 140, etc., a region of the sacrificial layer that overlaps with the insulating layer 125 may remain (see FIG. 35B ).

[0529] The heights of the top surfaces of the insulating layers 125 and 127 are preferably equal to or approximately equal to the heights of the top surfaces of at least one of the EL layers 113a, 113b, 113c, and 113d. The top surface of the insulating layer 127 is preferably flat and may have protrusions or recesses.

[0530] The sacrificial layer removal step can be performed using a method similar to that used in the sacrificial layer processing step. In particular, by using a wet etching method, damage to the EL layers 113 a, 113 b, 113 c, and the light-receiving layer 113 d can be reduced compared to when a dry etching method is used.

[0531] The first sacrificial layer and the second sacrificial layer may be removed in separate steps or in the same step.

[0532] Either or both of the first and second sacrificial layers may be removed by dissolving them in a solvent such as water or an alcohol, such as ethyl alcohol, methyl alcohol, isopropyl alcohol (IPA), or glycerin.

[0533] After removing the first sacrificial layer and the second sacrificial layer, a drying treatment may be performed to remove water contained in the EL layer and water adsorbed on the surface of the EL layer. For example, a heat treatment can be performed in an inert gas atmosphere or a reduced pressure atmosphere. The heat treatment can be performed at a substrate temperature of 50°C or higher and 200°C or lower, preferably 60°C or higher and 150°C or lower, and more preferably 70°C or higher and 120°C or lower. A reduced pressure atmosphere is preferable because it allows drying at a lower temperature.

[0534] Next, as shown in Fig. 35C , layer 114 is formed to cover insulating layers 125 and 127, EL layers 113a, 113b, 113c, and light-receiving layer 113d. As shown in Fig. 35C , in the cross-sectional view between Y1 and Y2, the end of layer 114 on the connection portion 140 side is located inside connection portion 140, and conductive layer 123 remains exposed. Note that, depending on the level of conductivity of layer 114, layer 114 may be provided at connection portion 140.

[0535] The materials that can be used for the layer 114 are as described above. The layer 114 can be formed by a method such as a vapor deposition method (including a vacuum deposition method), a transfer method, a printing method, an inkjet method, or a coating method. The layer 114 may also be formed using a premixed material.

[0536] If the insulating layers 125 and 127 were not provided, the layer 114 might come into contact with any of the pixel electrodes 111a, 111b, 111c, and 111d. Contact between these layers might cause a short circuit in the light-emitting device or the light-receiving device, especially if the layer 114 has high conductivity. However, in the display device of one embodiment of the present invention, the insulating layers 125 and 127 cover the side surfaces of the EL layers 113a, 113b, 113c, the light-receiving layer 113d, the pixel electrodes 111a, 111b, 111c, and 111d. This prevents the highly conductive layer 114 from coming into contact with these layers, thereby preventing a short circuit in the light-emitting device. This improves the reliability of the light-emitting device.

[0537] Then, as shown in FIG. 35C, a common electrode 115 is formed on the layer 114 and the conductive layer 123 .

[0538] The materials that can be used for the common electrode 115 are as described above. The common electrode 115 can be formed by, for example, sputtering or vacuum deposition. Alternatively, a film formed by deposition and a film formed by sputtering may be stacked.

[0539] Thereafter, a protective layer 131 is formed on the common electrode 115, and a protective layer 132 is formed on the protective layer 131. Furthermore, by using a resin layer 122, the substrate 120 is bonded onto the protective layer 132, whereby the display device 100 shown in FIG.

[0540] The materials and film formation methods that can be used for the protective layers 131 and 132 are as described above. Examples of film formation methods for the protective layers 131 and 132 include vacuum deposition, sputtering, CVD, and ALD. The protective layers 131 and 132 may be films formed using different film formation methods. Furthermore, the protective layers 131 and 132 may each have a single-layer structure or a multilayer structure.

[0541] Note that a mask (also referred to as an area mask, rough metal mask, or the like) for defining a film formation area may be used when forming the common electrode 115. Alternatively, without using the mask for forming the common electrode 115, the process of processing the common electrode 115 shown in Figures 36A and 36B may be performed after the process shown in Figure 35C, and then the process of forming the protective layer 131 may be performed.

[0542] As shown in Figures 36A and 29F, a resist mask 190e is formed on the common electrode 115. There is a portion at the end on the Y2 side in Figure 36A where the resist mask 190e is not provided. As shown in Figure 29F, the resist mask 190e is provided in an area overlapping each sub-pixel and the connection portion 140. In other words, the area where the resist mask 190e is not provided is located outside the connection portion 140.

[0543] 36B, a resist mask 190e is used to remove a portion of the common electrode 115. In this manner, the common electrode 115 can be processed.

[0544] Note that when the resist mask 190e is used, six photomasks are used in the series of manufacturing steps because the resist masks 190a, 190b, 190c, 190d, 190e, and the insulating film 127A are processed. When the resist mask 190e is not used, five photomasks are used in the series of manufacturing steps because the resist masks 190a, 190b, 190c, 190d, and the insulating film 127A are processed. On the other hand, a mask for defining a deposition area is used in the formation of the common electrode 115. In the manufacturing method of the display device of one embodiment of the present invention, it is not necessary to use a metal mask with a high-resolution pattern for forming an island-shaped EL layer, a mask for forming an island-shaped pixel electrode, and a mask for forming an insulating layer that covers an edge of the pixel electrode, which can reduce the number of masks and the cost.

[0545] 37B , layer 114 may not be provided, and common electrode 115 may be formed to cover insulating layers 125 and 127, EL layers 113a, 113b, 113c, and light-receiving layer 113d. In other words, all layers constituting the EL layers of light-emitting devices that emit light of different colors may be formed separately. In this case, the EL layers of each light-emitting device are all formed in an island shape.

[0546] Here, contact between any of the pixel electrode 111a, the pixel electrode 111b, the pixel electrode 111c, and the pixel electrode 111d and the common electrode 115 may cause a short circuit in the light-emitting device. However, in the display device of one embodiment of the present invention, the insulating layers 125 and 127 cover the side surfaces of the EL layer 113a, the EL layer 113b, the EL layer 113c, the light-receiving layer 113d, the pixel electrode 111a, the pixel electrode 111b, the pixel electrode 111c, and the pixel electrode 111d. This prevents the common electrode 115 from contacting these layers, thereby preventing a short circuit in the light-emitting device or the light-receiving device. This improves the reliability of the light-emitting device and the light-receiving device.

[0547] As shown in Figure 37C, if a part of the layer 101 including the transistor (specifically, the insulating layer located on the outermost surface) is not processed when processing the conductive film 111, a recess may not be formed in the layer 101 including the transistor.

[0548] 37D , the insulating layer 125 does not have to be provided. In this case, it is preferable to use an organic material that causes less damage to the EL layers 113 a, 113 b, 113 c, and the light-receiving layer 113 d for the insulating layer 127. For example, it is preferable to use an organic material such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinyl pyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin for the insulating layer 127.

[0549] When the layer 114 is provided in the connection portion 140, the conductive layer 123 and the common electrode 115 are electrically connected via the layer 114, as shown in FIG. 37E.

[0550] 38A to 38F show the cross-sectional structure of a region 139 including the insulating layer 127 and its periphery.

[0551] FIG. 38A shows an example in which the thicknesses of the EL layers 113a and 113b are different. The height of the top surface of the insulating layer 125 is the same or approximately the same as the height of the top surface of the EL layer 113a on the EL layer 113a side, and is the same or approximately the same as the height of the top surface of the EL layer 113b on the EL layer 113b side. The top surface of the insulating layer 127 has a gentle slope, with the EL layer 113a side being higher and the EL layer 113b side being lower. In this way, the heights of the insulating layers 125 and 127 are preferably the same as the height of the top surfaces of the adjacent EL layers. Alternatively, the top surface may have a flat portion that is the same as the height of the top surface of one of the adjacent EL layers.

[0552] 38B, the upper surface of insulating layer 127 has a region higher than the upper surface of EL layer 113a and the upper surface of EL layer 113b. The upper surface of insulating layer 127 has a shape that gently bulges out toward the center.

[0553] 38C , the insulating layer 127 has a region that is higher than the upper surfaces of the EL layers 113 a and 113 b. In addition, in region 139, the display device 100 has at least one of the first sacrificial layer 118 a and the second sacrificial layer 119 a, and the insulating layer 127 has a first region that is higher than the upper surfaces of the EL layers 113 a and 113 b and is located outside the insulating layer 125, and the first region is located on at least one of the first sacrificial layer 118 a and the second sacrificial layer 119 a. In addition, in region 139, the display device 100 has at least one of a first sacrificial layer 118b and a second sacrificial layer 119b, and has a second region in which the insulating layer 127 is higher than the upper surfaces of the EL layer 113a and the EL layer 113b and is located outside the insulating layer 125, and the second region is located on at least one of the first sacrificial layer 118b and the second sacrificial layer 119b.

[0554] The upper surface of the insulating layer 127 may have a shape corresponding to the shape of the surface on which the insulating layer 127 is to be formed (for example, the upper surfaces of the insulating layer 125, the second sacrificial layer 119a, and the second sacrificial layer 119b). Fig. 38C shows an example in which the upper surface of the insulating layer 127 has a recessed shape in the region overlapping the recess of the insulating layer 125.

[0555] 38D, the upper surface of insulating layer 127 has an area that is lower than the upper surfaces of EL layers 113a and 113b. The upper surface of insulating layer 127 has a gently sloping shape that is concave toward the center.

[0556] 38E, the upper surface of the insulating layer 125 has a region higher than the upper surface of the EL layer 113a and the upper surface of the EL layer 113b. That is, the insulating layer 125 protrudes from the surface on which the layer 114 is to be formed, forming a convex portion.

[0557] For example, when the insulating layer 125 is formed so as to be aligned or approximately aligned with the height of the sacrificial layer, the insulating layer 125 may be formed in a protruding shape as shown in FIG. 38E.

[0558] 38F, the upper surface of the insulating layer 125 has an area lower than the upper surfaces of the EL layers 113a and 113b. That is, the insulating layer 125 forms a recess on the surface on which the layer 114 is to be formed.

[0559] In this way, the insulating layer 125 and the insulating layer 127 can be applied in various shapes.

[0560] As described above, in the manufacturing method of the display device of this embodiment, the island-shaped EL layer is formed by forming the EL layer on the entire surface and then processing it, rather than by using a fine metal mask, so that the island-shaped EL layer can be formed with a uniform thickness, and a high-definition display device or a display device with a high aperture ratio can be realized.

[0561] The first, second, and third layers constituting the light-emitting device of each color are formed in separate processes. Therefore, each EL layer can be fabricated with a configuration (material, film thickness, etc.) suitable for the light-emitting device of each color. This allows the fabrication of light-emitting devices with excellent characteristics.

[0562] A display device according to one embodiment of the present invention includes an insulating layer covering each side surface of a pixel electrode, a light-emitting layer, and a carrier transport layer. In a manufacturing process of the display device, the EL layer is processed in a state in which the light-emitting layer and the carrier transport layer are stacked. Therefore, the display device has a structure in which damage to the light-emitting layer is reduced. Furthermore, the insulating layer prevents the pixel electrode from contacting the carrier injection layer or the common electrode, thereby preventing a short circuit of the light-emitting device.

[0563] The order in which the light-emitting device 130a, the light-emitting device 130b, the light-emitting device 130c, and the light-receiving device 130d are formed is not particularly limited.

[0564] This embodiment mode can be combined with other embodiment modes as appropriate. In addition, in this specification, when a plurality of configuration examples are shown in one embodiment mode, the configuration examples can be combined as appropriate.

[0565] Embodiment 3 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS.

[0566] The display device of the present embodiment can be a high-resolution display device or a large-sized display device. Therefore, the display device of the present embodiment can be used in electronic devices having relatively large screens, such as television devices, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound reproducing devices.

[0567] In this specification and the like, a display panel, which is one aspect of a display device, has a function of displaying (outputting) an image or the like on a display surface, and therefore the display panel is one aspect of an output device.

[0568] In this specification and the like, a display device to which a connector such as a flexible printed circuit board (FPC) or a tape carrier package (TCP) is attached, or to which an integrated circuit (IC) is mounted by a chip-on-glass (COG) method or a chip-on-film (COF) method or the like, may be referred to as a display panel module, a display module, or simply a display panel.

[0569] <Display Device 100A> FIG. 39 shows a perspective view of the display device 100A, and FIG. 40A shows a cross-sectional view of the display device 100A.

[0570] The display device 100A has a configuration in which a substrate 152 and a substrate 151 are bonded together. In Fig. 39, the substrate 152 is clearly indicated by a dashed line.

[0571] The display device 100A includes a display portion 162, a circuit 164, wiring 165, and the like. Fig. 39 shows an example in which an IC 173 and an FPC 172 are mounted on the display device 100A. Therefore, the configuration shown in Fig. 39 can also be considered as a display module including the display device 100A, an IC (integrated circuit), and an FPC.

[0572] The circuit 164 can be, for example, a scanning line driver circuit.

[0573] The wiring 165 has a function of supplying signals and power to the display portion 162 and the circuit 164. The signals and power are input to the wiring 165 from the outside via the FPC 172 or from the IC 173.

[0574] 39 shows an example in which an IC 173 is provided on a substrate 151 by a chip-on-glass (COG) method or a chip-on-film (COF) method. The IC 173 may be, for example, an IC having a scanning line driver circuit or a signal line driver circuit. The display device 100A and the display module may not include an IC. Alternatively, the IC may be mounted on an FPC by a COF method or the like.

[0575] FIG. 40A shows an example of a cross section of the display device 100A, in which a part of a region including the FPC 172, a part of the circuit 164, a part of the display unit 162, and a part of a region including an end portion are cut away.

[0576] The display device 100A has a light-emitting device, a light-receiving device, a transistor 207, a transistor 205, etc. between a substrate 151 and a substrate 152. Fig. 40A shows a light-emitting device 130a that emits red light, a light-emitting device 130b that emits green light, and a light-receiving device 130d as the light-emitting device and the light-receiving device.

[0577] Here, when a pixel of a display device has three types of subpixels having light-emitting devices that emit different colors, the three subpixels include subpixels of three colors of R, G, and B, or subpixels of three colors of yellow (Y), cyan (C), and magenta (M), etc. When a pixel of a display device has four subpixels, the four subpixels include subpixels of four colors of R, G, B, and white (W), or subpixels of four colors of R, G, B, and Y, etc.

[0578] The light-emitting device 130a and the light-emitting device 130b have an optical adjustment layer between the pixel electrode and the EL layer, and the light-receiving device 130d has an optical adjustment layer between the pixel electrode and the light-receiving layer. As the optical adjustment layer, the light-emitting device 130a has a conductive layer 126a, the light-emitting device 130b has a conductive layer 126b, and the light-receiving device 130d has a conductive layer 126d. For details of the light-emitting devices and the light-receiving devices, refer to Embodiment 1. The side surfaces of the pixel electrode 111a, the pixel electrode 111b, the pixel electrode 111d, the conductive layers 126a, 126b, and 126d, the EL layer 113a, the EL layer 113b, and the light-receiving layer 113d are covered with insulating layers 125 and 127, respectively. A layer 114 is provided on the EL layer 113a, the EL layer 113b, the light-receiving layer 113d, and the insulating layers 125 and 127, and a common electrode 115 is provided on the layer 114. In addition, a protective layer 131 is provided on each of the light-emitting device 130a, the light-emitting device 130b, and the light-receiving device 130d. A protective layer 132 is provided on the protective layer 131.

[0579] The protective layer 132 and the substrate 152 are bonded via an adhesive layer 142. A solid sealing structure, a hollow sealing structure, or the like can be applied to seal the light-emitting device. In FIG. 40A , the space between the substrates 152 and 151 is filled with the adhesive layer 142, and a solid sealing structure is applied. Alternatively, the space may be filled with an inert gas (such as nitrogen or argon), and a hollow sealing structure may be applied. In this case, the adhesive layer 142 may be provided so as not to overlap with the light-emitting device. Alternatively, the space may be filled with a resin different from the frame-shaped adhesive layer 142.

[0580] The pixel electrode 111 a , the pixel electrode 111 b , and the pixel electrode 111 d are each connected to a conductive layer 222 b of the transistor 205 through an opening provided in the insulating layer 214 .

[0581] Recesses are formed in the pixel electrodes 111a, 111b, and 111d so as to cover the openings formed in the insulating layer 214. The recesses are preferably filled with a layer 128. It is also preferable that a conductive layer 126a is formed over the pixel electrodes 111a and the layer 128, a conductive layer 126b is formed over the pixel electrodes 111b and the layer 128, and a conductive layer 126d is formed over the pixel electrodes 111d and the layer 128. The conductive layers 126a, 126b, and 126d can also be referred to as pixel electrodes.

[0582] The layer 128 has a function of planarizing the recesses of the pixel electrodes 111a, 111b, and 111d. By providing the layer 128, unevenness on the surfaces on which the EL layer and the light-receiving layer are formed can be reduced, and coverage can be improved. Furthermore, by providing the conductive layers 126a, 126b, and 126d electrically connected to the pixel electrodes 111a, 111b, and 111d on the pixel electrodes 111a, 111b, and 111d, respectively, the regions overlapping with the recesses of the pixel electrodes 111a, 111b, and 111d can also be used as light-emitting regions in some cases. This can increase the aperture ratio of the pixel.

[0583] The layer 128 may be an insulating layer or a conductive layer. Various inorganic insulating materials, organic insulating materials, and conductive materials can be used as appropriate for the layer 128. In particular, the layer 128 is preferably formed using an insulating material.

[0584] An insulating layer containing an organic material can be suitably used for the layer 128. For example, acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene resin, phenolic resin, precursors of these resins, or the like can be used for the layer 128. Alternatively, a photosensitive resin can be used for the layer 128. The photosensitive resin can be a positive-type material or a negative-type material.

[0585] By using a photosensitive resin, the layer 128 can be formed only through exposure and development steps, and the influence of dry etching, wet etching, etc. on the surfaces of the pixel electrodes 111 a, 111 b, and 111 d can be reduced. Furthermore, by forming the layer 128 using a negative photosensitive resin, the layer 128 can sometimes be formed using the same photomask (exposure mask) as that used to form the openings in the insulating layer 214.

[0586] The conductive layer 126a is provided on the pixel electrode 111a and the layer 128. The conductive layer 126a has a first region in contact with the upper surface of the pixel electrode 111a and a second region in contact with the upper surface of the layer 128. It is preferable that the height of the upper surface of the pixel electrode 111a in contact with the first region and the height of the upper surface of the layer 128 in contact with the second region are the same or approximately the same.

[0587] Similarly, the conductive layer 126b is provided on the pixel electrode 111b and the layer 128. The conductive layer 126b has a first region in contact with the upper surface of the pixel electrode 111b and a second region in contact with the upper surface of the layer 128. It is preferable that the height of the upper surface of the pixel electrode 111b in contact with the first region and the height of the upper surface of the layer 128 in contact with the second region are the same or approximately the same.

[0588] The conductive layer 126d is provided on the pixel electrode 111d and the layer 128. The conductive layer 126d has a first region in contact with the upper surface of the pixel electrode 111d and a second region in contact with the upper surface of the layer 128. It is preferable that the height of the upper surface of the pixel electrode 111d in contact with the first region and the height of the upper surface of the layer 128 in contact with the second region are the same or approximately the same.

[0589] The pixel electrode includes a material that reflects visible light, and the counter electrode includes a material that transmits visible light.

[0590] The display device 100A is a top-emission type. Light emitted by the light-emitting device is emitted toward the substrate 152. The substrate 152 is preferably made of a material that is highly transparent to visible light. It is even more preferable that the substrate 152 is made of a material that is highly transparent to visible light and infrared light. Light enters the light-receiving device through the substrate 152.

[0591] The stacked structure from the substrate 151 to the insulating layer 214 corresponds to the substrate 23 described in Embodiment 1 or the layer 101 including the transistor described in Embodiment 2 or the like.

[0592] The transistor 207 and the transistor 205 are both formed over a substrate 151. These transistors can be manufactured using the same material and through the same process.

[0593] An insulating layer 217, an insulating layer 213, an insulating layer 215, and an insulating layer 214 are provided over the substrate 151 in this order. A part of the insulating layer 217 functions as a gate insulating layer for each transistor. A part of the insulating layer 213 functions as a gate insulating layer for each transistor. The insulating layer 215 is provided to cover the transistor. The insulating layer 214 is provided to cover the transistor and functions as a planarization layer. Note that the number of gate insulating layers and the number of insulating layers covering the transistors are not limited, and each may be a single layer or two or more layers.

[0594] At least one insulating layer covering the transistor is preferably made of a material that is resistant to the diffusion of impurities such as water and hydrogen. This allows the insulating layer to function as a barrier insulating film. With this structure, it is possible to effectively prevent impurities from diffusing into the transistor from the outside, thereby improving the reliability of the display device.

[0595] The insulating layer 217, the insulating layer 213, and the insulating layer 215 are preferably formed using an inorganic insulating film. Examples of the inorganic insulating film that can be used include a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, and an aluminum nitride film. Alternatively, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, and a neodymium oxide film may also be used. Two or more of the above insulating films may be stacked.

[0596] An organic insulating film is suitable for the insulating layer 214, which functions as a planarization layer. Materials that can be used for the organic insulating film include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, and precursors of these resins. The insulating layer 214 may also have a laminated structure of an organic insulating film and an inorganic insulating film. The outermost layer of the insulating layer 214 preferably functions as an etching protection film. This can prevent recesses from being formed in the insulating layer 214 during processing of the pixel electrode 111a, the conductive layer 126a, etc. Alternatively, recesses may be formed in the insulating layer 214 during processing of the pixel electrode 111a, the conductive layer 126a, etc.

[0597] Here, organic insulating films often have lower barrier properties than inorganic insulating films. Therefore, it is preferable that the organic insulating film has an opening near the edge of the display device 100A. This can prevent impurities from entering through the edge of the display device 100A via the organic insulating film. Alternatively, the organic insulating film may be formed so that the edge of the organic insulating film is located inside the edge of the display device 100A, so that the organic insulating film is not exposed at the edge of the display device 100A.

[0598] 40A , an opening is formed in insulating layer 214. This makes it possible to prevent impurities from entering display unit 162 from the outside through insulating layer 214, even when an organic insulating film is used for insulating layer 214. This makes it possible to improve the reliability of display device 100A.

[0599] The transistor 207 and the transistor 205 each include a conductive layer 221 that functions as a gate, an insulating layer 217 that functions as a gate insulating layer, conductive layers 222a and 222b that function as a source and a 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 217 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.

[0600] The structure of the transistor included in the display device of this embodiment is not particularly limited. For example, a planar transistor, a staggered transistor, an inverted staggered transistor, or the like can be used. Furthermore, either a top-gate transistor or a bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below a semiconductor layer in which a channel is formed.

[0601] The transistors 207 and 205 have a structure in which a semiconductor layer in which a channel is formed is sandwiched between two gates. The two gates may be connected and supplied with the same signal to drive the transistors. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential for controlling the threshold voltage to one of the two gates and a potential for driving to the other.

[0602] The crystallinity of a semiconductor material used for a transistor is not particularly limited, and any of an amorphous semiconductor and a crystalline semiconductor (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0603] The semiconductor layer of the transistor preferably contains metal oxide (also referred to as an oxide semiconductor). That is, the display device of this embodiment preferably uses a transistor in which a channel formation region is formed using metal oxide (hereinafter referred to as an OS transistor). Alternatively, the semiconductor layer of the transistor may contain silicon. Examples of silicon include amorphous silicon and crystalline silicon (such as low-temperature polysilicon and single-crystal silicon).

[0604] The semiconductor layer preferably contains, for example, indium, M (wherein M is one or more elements selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more elements selected from aluminum, gallium, yttrium, and tin.

[0605] In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also referred to as IGZO) as the semiconductor layer.

[0606] When the semiconductor layer is an In-M-Zn oxide, the atomic ratio of In in the In-M-Zn oxide is preferably equal to or greater than the atomic ratio of M. Examples of atomic ratios of metal elements in such In-M-Zn oxides include a composition in which In:M:Zn=1:1:1 or thereabouts, a composition in which In:M:Zn=1:1:1.2 or thereabouts, a composition in which In:M:Zn=2:1:3 or thereabouts, a composition in which In:M:Zn=3:1:2 or thereabouts, a composition in which In:M:Zn=4:2:3 or thereabouts, a composition in which In:M:Zn=4:2:4.1 or thereabouts, a composition in which In:M:Zn=5:1:3 or thereabouts, a composition in which In:M:Zn=5:1:6 or thereabouts, a composition in which In:M:Zn=5:1:7 or thereabouts, a composition in which In:M:Zn=5:1:8 or thereabouts, a composition in which In:M:Zn=6:1:6 or thereabouts, and a composition in which In:M:Zn=5:2:5 or thereabouts. The term "nearby composition" includes a range of ±30% of the desired atomic ratio.

[0607] For example, when describing a composition having an atomic ratio of In:Ga:Zn=4:2:3 or thereabout, this includes a case where, when In is taken as 4, Ga is 1 to 3 and Zn is 2 to 4. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn=5:1:6 or thereabout, this includes a case where, when In is taken as 5, Ga is more than 0.1 and 2 or less and Zn is 5 to 7. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn=1:1:1 or thereabout, this includes a case where, when In is taken as 1, Ga is more than 0.1 and 2 or less and Zn is more than 0.1 and 2 or less.

[0608] The transistors included in the circuit 164 may have the same structure as or different from the transistors included in the display portion 162. The transistors included in the circuit 164 may all have the same structure or may have two or more types. Similarly, the transistors included in the display portion 162 may all have the same structure or may have two or more types.

[0609] 40B and 40C show other examples of transistor configurations.

[0610] The transistor 209 and the transistor 210 each include a conductive layer 221 functioning as a gate, an insulating layer 217 functioning as a gate insulating layer, a semiconductor layer 231 including a channel formation 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 functioning as a gate insulating layer, a conductive layer 223 functioning as a gate, and an insulating layer 215 covering the conductive layer 223. The insulating layer 217 is located between the conductive layer 221 and the channel formation region 231i. The insulating layer 225 is located at least between the conductive layer 223 and the channel formation region 231i. Furthermore, an insulating layer 218 covering the transistor may be provided.

[0611] 40B shows an example in which the insulating layer 225 covers the top surface and side surface of the semiconductor layer 231. The conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings provided in the insulating layer 225 and the insulating layer 215, respectively. One of the conductive layer 222a and the conductive layer 222b functions as a source, and the other functions as a drain.

[0612] 40C , 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 insulating layer 225 is processed using the conductive layer 223 as a mask, thereby manufacturing the structure shown in FIG. 40C . In FIG. 40C , the insulating layer 215 is provided to cover the insulating layer 225 and the conductive layer 223, and the conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings in the insulating layer 215.

[0613] A connection portion 204 is provided in a region of the substrate 151 where the substrate 152 does not overlap. In the connection portion 204, the wiring 165 is electrically connected to the FPC 172 via a conductive layer 166 and a connection layer 242. The conductive layer 166 has an example of a stacked structure including a conductive film obtained by processing the same conductive film as the pixel electrodes 111a, 111b, and 111d, and a conductive film obtained by processing the same conductive film as the conductive layers 126a, 126b, and 126d. The conductive layer 166 is exposed on the top surface of the connection portion 204. This allows the connection portion 204 and the FPC 172 to be electrically connected via the connection layer 242.

[0614] It is preferable to provide a light-shielding layer 117 on the surface of substrate 152 facing substrate 151. In addition, various optical members can be arranged on the outside of substrate 152. Examples of optical members include a polarizing plate, a retardation plate, a light diffusion layer (such as a diffusion film), an anti-reflection layer, and a light-collecting film. In addition, an antistatic film that suppresses the adhesion of dust, a water-repellent film that makes it difficult for dirt to adhere, a hard coat film that suppresses the occurrence of scratches during use, an impact absorbing layer, etc. may be arranged on the outside of substrate 152.

[0615] By providing the protective layers 131 and 132 that cover the light-emitting device, impurities such as water can be prevented from entering the light-emitting device, and the reliability of the light-emitting device can be improved.

[0616] In a region 228 near the edge of the display device 100A, it is preferable that the insulating layer 215 and the protective layer 131 or the protective layer 132 contact each other through the opening in the insulating layer 214. In particular, it is preferable that the inorganic insulating films contact each other. This makes it possible to prevent impurities from entering the display unit 162 from the outside via the organic insulating film. This can therefore improve the reliability of the display device 100A.

[0617] The substrate 151 and the substrate 152 can each be made of glass, quartz, ceramic, sapphire, resin, metal, alloy, semiconductor, or the like. A material that transmits light is used for the substrate on the side from which light from the light-emitting device is extracted. Using a flexible material for the substrate 151 and the substrate 152 can increase the flexibility of the display device. Alternatively, a polarizing plate may be used for the substrate 151 or the substrate 152.

[0618] Substrates 151 and 152 can be made of polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyacrylonitrile resin, acrylic resin, polyimide resin, polymethyl methacrylate resin, polycarbonate (PC) resin, polyethersulfone (PES) resin, polyamide resin (nylon, aramid, etc.), polysiloxane resin, cycloolefin resin, polystyrene resin, polyamideimide resin, polyurethane resin, polyvinyl chloride resin, polyvinylidene chloride resin, polypropylene resin, polytetrafluoroethylene (PTFE) resin, ABS resin, cellulose nanofiber, etc. One or both of substrates 151 and 152 can be made of glass having a thickness sufficient to provide flexibility.

[0619] When a circularly polarizing plate is superimposed on a display device, it is preferable that the display device has a substrate with high optical isotropy. A substrate with high optical isotropy has small birefringence (or a small amount of birefringence).

[0620] The absolute value of the retardation (phase difference) of a substrate having high optical isotropy is preferably 30 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less.

[0621] Examples of films with high optical isotropy include triacetyl cellulose (TAC, also known as cellulose triacetate) films, cycloolefin polymer (COP) films, cycloolefin copolymer (COC) films, and acrylic films.

[0622] When a film is used as a substrate, the film may absorb water, causing deformation such as wrinkles in the display panel. Therefore, it is preferable to use a film with low water absorption for the substrate. For example, it is preferable to use a film with a water absorption rate of 1% or less, more preferably 0.1% or less, and even more preferably 0.01% or less.

[0623] The adhesive layer can be made of various curable adhesives, such as photo-curable adhesives (e.g., ultraviolet curable), reactive curable adhesives, thermosetting adhesives, and anaerobic adhesives. Examples of such adhesives include epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, and EVA (ethylene vinyl acetate) resin. Materials with low moisture permeability, such as epoxy resin, are particularly preferred. Two-component resins may also be used. Adhesive sheets, etc., may also be used.

[0624] The connection layer 242 may be made of an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0625] Materials that can be used for conductive layers such as the gate, source, and drain of a transistor, as well as various wirings and electrodes that constitute a display device include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, and tungsten, and alloys containing these metals as main components, etc. Films containing these materials can be used as a single layer or a stacked layer structure.

[0626] Examples of light-transmitting conductive materials include conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, and zinc oxide containing gallium, or graphene. Alternatively, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, and titanium, or alloy materials containing such metal materials, can be used. Alternatively, nitrides of such metal materials (e.g., titanium nitride) can be used. When using metal materials or alloy materials (or their nitrides), it is preferable to thin them sufficiently to ensure light-transmitting properties. A stacked film of the above materials can also be used as the conductive layer. For example, a stacked film of an alloy of silver and magnesium and indium tin oxide is preferable because it can enhance conductivity. These materials can also be used for conductive layers such as various wirings and electrodes constituting display devices, and conductive layers (conductive layers functioning as pixel electrodes or common electrodes) in light-emitting devices.

[0627] Examples of insulating materials that can be used for each insulating layer include resins such as acrylic resin and epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, and aluminum oxide.

[0628] 41 is different from the display device 100A mainly in that it is a bottom emission type. Note that a description of the same parts as those of the display device 100A will be omitted.

[0629] Light emitted by the light-emitting device is emitted toward the substrate 151. The substrate 151 is preferably made of a material that is highly transparent to visible light. It is more preferable that the substrate 151 is made of a material that is highly transparent to visible light and infrared light. On the other hand, the light-transmitting property of the material used for the substrate 152 does not matter. Light enters the light-receiving device through the substrate 151.

[0630] A light-shielding layer 117 is preferably formed between the substrate 151 and the transistor 207 and between the substrate 151 and the transistor 205. Fig. 41 shows an example in which the light-shielding layer 117 is provided over the substrate 151, the insulating layer 153 is provided over the light-shielding layer 117, and the transistors 207, 205, and the like are provided over the insulating layer 153.

[0631] This embodiment mode can be combined with other embodiment modes as appropriate.

[0632] Embodiment 4 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS.

[0633] The display device of the present embodiment can be a high-definition display device, and therefore can be used as a display unit of a wearable device that can be worn on the head, such as a wristwatch-type or bracelet-type information terminal (wearable device), a head-mounted display or other VR (Virtual Reality) device, or a glasses-type AR (Augmented Reality) device.

[0634] 42A shows a perspective view of a display module 280. The display module 280 includes a display device 100C and an FPC 290. Note that the display device included in the display module 280 is not limited to the display device 100C, and may be a display device 100D or a display device 100E, which will be described later.

[0635] The display module 280 has a substrate 291 and a substrate 292. The display module 280 has a display portion 281. The display portion 281 is a region that displays an image in the display module 280, and is a region where light from each pixel provided in a pixel portion 284 (described later) can be viewed.

[0636] 42B is a perspective view schematically illustrating the configuration on the substrate 291 side. A circuit portion 282, a pixel circuit portion 283 on the circuit portion 282, and a pixel portion 284 on the pixel circuit portion 283 are stacked on the substrate 291. A terminal portion 285 for connecting to the FPC 290 is provided in a portion of the substrate 291 that does not overlap with the pixel portion 284. The terminal portion 285 and the circuit portion 282 are electrically connected by a wiring portion 286 composed of a plurality of wirings.

[0637] The pixel section 284 has a plurality of periodically arranged pixels 284a. An enlarged view of one pixel 284a is shown on the right side of Fig. 42B. The pixel 284a has a light-emitting device 130a, a light-emitting device 130b, a light-emitting device 130c, and a light-receiving device 130d, which emit light of different colors. The light-emitting devices and the light-receiving devices can be arranged in a stripe array as shown in Fig. 42B. Various light-emitting device arrangement methods, such as a delta array or a pentile array, can also be applied.

[0638] The pixel circuit section 283 has a plurality of pixel circuits 283a arranged periodically.

[0639] Each pixel circuit 283a is a circuit that controls the emission of light from a light-emitting device and the reception of light from a light-receiving device included in each pixel 284a. For example, if each pixel 284a has three light-emitting devices and one light-receiving device, each pixel circuit 283a is a circuit that controls the emission of light from the three light-emitting devices and the reception of light from one light-receiving device. Each pixel circuit 283a may be configured to have three circuits that control the emission of light from one light-emitting device and one circuit that controls the reception of light from one light-receiving device. For example, the pixel circuit 283a may be configured to include at least one selection transistor, one current control transistor (drive 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 either the source or the drain. This realizes an active matrix display device. For example, the pixel circuit described in Embodiment 1 can be used as the pixel circuit 283a.

[0640] The circuit portion 282 includes a circuit for driving each pixel circuit 283 a of the pixel circuit portion 283. For example, the circuit portion 282 preferably includes one or both of a gate line driver circuit and a source line driver circuit. In addition, the circuit portion 282 may include at least one of an arithmetic circuit, a memory circuit, a power supply circuit, and the like.

[0641] The FPC 290 functions as wiring for supplying a video signal, a power supply potential, or the like from the outside to the circuit portion 282. An IC may be mounted on the FPC 290.

[0642] The display module 280 can be configured such that one or both of the pixel circuit unit 283 and the circuit unit 282 are stacked below the pixel unit 284, thereby enabling the aperture ratio (effective display area ratio) of the display unit 281 to be extremely high. For example, the aperture ratio of the display unit 281 can be 40% or more and less than 100%, preferably 50% or more and 95% or less, and more preferably 60% or more and 95% or less. Furthermore, the pixels 284a can be arranged at an extremely high density, enabling the resolution of the display unit 281 to be extremely high. For example, it is preferable that the pixels 284a be arranged in the display unit 281 at a resolution of 500 ppi or more, preferably 1000 ppi or more, more preferably 2000 ppi or more, even more preferably 3000 ppi or more, even more preferably 5000 ppi or more, and even more preferably 6000 ppi or more, and 20,000 ppi or less, or 30,000 ppi or less.

[0643] Because such a display module 280 has 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 in which the display unit of the display module 280 is viewed through lenses, the display module 280 has an extremely high-resolution display unit 281, so even when the display unit is enlarged with lenses, the 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 units. For example, it can be suitably used in the display unit of a wearable electronic device such as a wristwatch.

[0644] <Display Device 100C> A display device 100C shown in FIG. 43 includes a substrate 301, a light-emitting device 130a, a light-emitting device 130b, a light-emitting device 130c, a light-receiving device 130d, a capacitor 240, and a transistor 310.

[0645] Substrate 301 corresponds to substrate 291 in Figures 42A and 42B.

[0646] The transistor 310 has a channel formation region in a substrate 301. The substrate 301 can be, for example, a semiconductor substrate such as a single crystal silicon substrate. The transistor 310 includes a part of the substrate 301, a conductive layer 311, a low-resistance region 312, an insulating layer 313, and an insulating layer 314. The conductive layer 311 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 in which the substrate 301 is doped with impurities and functions as one of a source and a drain. The insulating layer 314 is provided to cover a side surface of the conductive layer 311.

[0647] An isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301 .

[0648] An insulating layer 261 is provided to cover the transistor 310 , and a capacitor 240 is provided over the insulating layer 261 .

[0649] The capacitor 240 has a conductive layer 241, a conductive layer 245, and an insulating layer 243 located therebetween. The conductive layer 241 functions as one electrode of the capacitor 240, the conductive layer 245 functions as the other electrode of the capacitor 240, and the insulating layer 243 functions as a dielectric of the capacitor 240.

[0650] The conductive layer 241 is provided over the insulating layer 261 and is buried in the insulating layer 254. The conductive layer 241 is electrically connected to one of the source and drain of the transistor 310 by a plug 271 buried in the insulating layer 261. The insulating layer 243 is provided to cover the conductive layer 241. The conductive layer 245 is provided in a region overlapping with the conductive layer 241 with the insulating layer 243 interposed therebetween.

[0651] An insulating layer 255a is provided to cover the capacitor 240, an insulating layer 255b is provided on the insulating layer 255a, and the light-emitting devices 130a, 130b, 130c, and 130d are provided on the insulating layer 255b. The side surfaces of the pixel electrodes 111a, 111b, 111c, 111d, the EL layers 113a, 113b, 113c, and the light-receiving layer 113d are covered with insulating layers 125 and 127, respectively. A layer 114 is provided on the EL layers 113a, 113b, 113c, the light-receiving layer 113d, the insulating layer 125, and the insulating layer 127, and a common electrode 115 is provided on the layer 114. Furthermore, a protective layer 131 is provided on the light-emitting devices 130a, 130b, 130c, and 130d. A protective layer 132 is provided on the protective layer 131, and the substrate 120 is bonded to the protective layer 132 by a resin layer 122. For details about the components from the light-emitting devices to the substrate 120, please refer to the above description.

[0652] The insulating layers 255a and 255b can be formed using various inorganic insulating films such as an insulating oxide film, an insulating nitride film, an oxynitride insulating film, and an insulating nitride oxide film. The insulating layer 255a is preferably formed using an insulating oxide film or an oxynitride insulating film such as a silicon oxide film, a silicon oxynitride film, or an aluminum oxide film. The insulating layer 255b is preferably formed using a nitride insulating film or a nitride oxide insulating film such as a silicon nitride film or a silicon nitride oxide film. More specifically, it is preferable to use a silicon oxide film as the insulating layer 255a and a silicon nitride film as the insulating layer 255b. The insulating layer 255b preferably functions as an etching protective film. Alternatively, a nitride insulating film or a nitride oxide insulating film may be used as the insulating layer 255a, and an oxide insulating film or an ...

Claims

1. A light emitting device, a light receiving device, and a substrate, The light-emitting device has a first electrode on the substrate, a light-emitting layer, a first electron transport layer, an electron injection layer, and a second electrode stacked in this order; the light-receiving device has a third electrode on the substrate, an active layer, a first hole transport layer, the electron injection layer, and the second electrode stacked in this order; The light receiving device comprises a second electron transport layer between the third electrode and the active layer.

2. In claim 1, The light emitting device comprises a display device having a second hole transport layer between the first electrode and the light emitting layer.

3. In claim 1 or 2, The light-emitting device has a function of emitting visible light, The light receiving device is a display device having a function of detecting visible light.

4. In any one of claims 1 to 3, the light-emitting device has a function of emitting infrared light, The light receiving device is a display device having a function of detecting infrared light.

5. In any one of claims 1 to 4, The first electrode is provided with a first potential; the second electrode is given a second potential lower than the first potential; A display device in which the third electrode is given a third potential higher than the second potential.

6. In any one of claims 1 to 5, a pixel portion including a plurality of first pixels, a plurality of second pixels, a plurality of third pixels, and a plurality of fourth pixels; the first pixel, the second pixel, the third pixel, and the fourth pixel each have the light emitting device or the light receiving device; the pixel unit has a first array in which the second pixel, the first pixel, the second pixel, and the third pixel are repeatedly arranged in this order in a first direction, and a second array in which the fourth pixel, the first pixel, the fourth pixel, and the third pixel are repeatedly arranged in this order, the first array and the second array are alternately and repeatedly arranged in a second direction perpendicular to the first direction; the pixel unit has a third array in which the second pixels and the fourth pixels are alternately and repeatedly arranged in the second direction, and a fourth array in which the first pixels and the third pixels are alternately and repeatedly arranged in the second direction, A display device in which the third array and the fourth array are alternately and repeatedly arranged in the first direction.

7. In claim 6, the first pixel, the second pixel, and the third pixel each have a light emitting device that emits light in a different wavelength region; The fourth pixel is a display device having the light receiving device.

8. In claim 6 or 7, the third pixel has a light emitting device that emits green light; an area of ​​the third pixel is smaller than an area of ​​the first pixel; A display device in which the area of ​​the third pixel is smaller than the area of ​​the second pixel.