Display device, display module, and electronic apparatus

Abstract

Provided is a high-resolution display device that has a light detection function. The display device comprises a light-receiving device and a light-emitting device. The light-receiving device comprises a first electrode, an active layer over the first electrode, and a second electrode over the active layer. The light-emitting device comprises a third electrode, a light-emitting layer over the third electrode, and a second electrode over the light-emitting layer. In a top view, the active layer and the light-emitting layer have portions overlapping with one another on the outer side of the first electrode and on the outer side of the third electrode.

Description

Display device, display module, and electronic device

[0001] FIELD OF THE INVENTION One embodiment of the present invention relates to a display device, a display module, and an electronic device. BACKGROUND OF THE INVENTION One embodiment of the present invention relates to a display device including a light-receiving device and a light-emitting 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 semiconductor devices, display devices, light-emitting devices, power storage devices, memory devices, electronic devices, lighting devices, input devices (e.g., touch sensors), input / output devices (e.g., touch panels), driving methods thereof, and manufacturing methods thereof.

[0003] In recent years, display devices have been expected to be used in a variety of applications. For example, applications of large display devices include home television devices (also called televisions or television receivers), digital signage, public information displays (PIDs), etc. Furthermore, development of smartphones and tablet devices equipped with touch panels as mobile information terminals is progressing.

[0004] As a display device, for example, a light-emitting device having a light-emitting device (also referred to as a light-emitting element) has been developed. A light-emitting device (also referred to as an EL device or an EL element) using electroluminescence (hereinafter referred to as EL) has features such as being easily thin and lightweight, being capable of responding quickly to an input signal, and being capable of being driven using a DC constant voltage power supply, and is therefore applied to a display device. For example, Patent Document 1 discloses a flexible light-emitting device using an organic EL element.

[0005] JP 2014-197522 A

[0006] An object of one embodiment of the present invention is to provide a high-resolution display device having a light detection function.An object of one embodiment of the present invention is to provide a highly convenient display device.An object of one embodiment of the present invention is to provide a multifunctional display device.An object of one embodiment of the present invention is to provide a display device with high display quality.An object of one embodiment of the present invention is to provide a display device with high sensitivity in light detection.An object of one embodiment of the present invention is to provide a novel display device.

[0007] 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.

[0008] One embodiment of the present invention is a display device including a light-receiving device and a light-emitting device. The light-receiving device includes a first electrode, an active layer over the first electrode, and a second electrode over the active layer. The light-emitting device includes a third electrode, a light-emitting layer over the third electrode, and a second electrode over the light-emitting layer. In a top view, the active layer and the light-emitting layer have overlapping portions outside the first electrode and outside the third electrode.

[0009] The light-receiving device and the light-emitting device preferably have a common layer, which preferably has a portion located between the first electrode and the second electrode and a portion located between the first electrode and the third electrode.

[0010] The light-emitting layer preferably has a portion located above the active layer.

[0011] One embodiment of the present invention is a display device including a light-receiving device, a first light-emitting device, and a second light-emitting device. The light-receiving device includes a first electrode, an active layer over the first electrode, and a second electrode over the active layer. The first light-emitting device includes a third electrode, a first light-emitting layer over the third electrode, and a second electrode over the first light-emitting layer. The second light-emitting device includes a fourth electrode, a second light-emitting layer over the fourth electrode, and a second electrode over the second light-emitting layer. The first light-emitting layer and the second light-emitting layer include light-emitting materials different from each other. In a cross-sectional view, the active layer includes a portion located between the first light-emitting layer and the second light-emitting layer.

[0012] The light-receiving device, the first light-emitting device, and the second light-emitting device preferably have a common layer, which preferably has a portion located between the first electrode and the second electrode, a portion located between the first electrode and the third electrode, and a portion located between the fourth electrode and the third electrode.

[0013] The display device having any of the above configurations is preferably flexible.

[0014] One embodiment of the present invention is a display module including a display device having any of the above structures, and including a connector such as a flexible printed circuit (hereinafter referred to as FPC) or a tape carrier package (TCP) attached thereto, or a display module including an integrated circuit (IC) mounted thereon by a chip-on-glass (COG) method, a chip-on-film (COF) method, or the like.

[0015] 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.

[0016] According to one embodiment of the present invention, a high-resolution display device having a light detection function can be provided. According to one embodiment of the present invention, a highly convenient display device can be provided. According to one embodiment of the present invention, a multifunctional display device can be provided. According to one embodiment of the present invention, a display device with high display quality can be provided. According to one embodiment of the present invention, a display device with high light detection sensitivity can be provided. According to one embodiment of the present invention, a novel display device can be provided.

[0017] 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.

[0018] FIGS. 1A to 1D are cross-sectional views showing an example of a display device. FIG. 1E is a view showing an example of an image. FIGS. 2A to 2I are views showing an example of a pixel of a display device. FIG. 3 is a top view showing an example of a display device. FIGS. 4A to 4C are cross-sectional views showing an example of a display device. FIGS. 5A to 5C are cross-sectional views showing an example of a manufacturing method of a display device. FIGS. 6A and 6B are cross-sectional views showing an example of a manufacturing method of a display device. FIGS. 7A and 7B are cross-sectional views showing an example of a manufacturing method of a display device. FIG. 8 is a perspective view showing an example of a display device. FIG. 9 is a cross-sectional view showing an example of a display device. FIG. 10 is a cross-sectional view showing an example of a display device. FIG. 11A is a cross-sectional view showing an example of a display device. FIG. 11B is a cross-sectional view showing an example of a transistor. FIGS. 12A and 12B are circuit diagrams showing an example of a pixel circuit. FIGS. 13A and 13B are views showing examples of electronic devices. FIGS. 14A to 14D are views showing examples of electronic devices. FIGS. 15A to 15E are views showing examples of electronic devices. FIGS. 16A to 16G are views showing examples of electronic devices.

[0019] 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.

[0020] 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.

[0021] Furthermore, 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.

[0022] 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."

[0023] 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 FMM structure or 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.

[0024] Embodiment 1 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS. 1A to 11B. FIG.

[0025] The display device of this embodiment has a light-receiving device and a light-emitting device in a display unit. In the display device of this embodiment, the light-emitting devices are arranged in a matrix in the display unit, and an image can be displayed on the display unit. In addition, the light-receiving devices are arranged in a matrix in the display unit, and the display unit also functions as a light-receiving unit. The light-receiving unit can be used as either an image sensor or a touch sensor, or both. That is, by detecting light with the light-receiving unit, it is possible to capture an image and detect the proximity or contact of an object (such as a finger or a pen).

[0026] Furthermore, the display device of this embodiment can use the light-emitting device as a light source of a sensor. For example, not only can an image be displayed using all subpixels of the display device, but also some subpixels can emit light as light sources, other pixels can detect light, and the remaining subpixels can display an image. Therefore, a light-receiving unit and a light source are not required to be provided separately from the display device, and the number of components in the electronic device can be reduced. For example, a fingerprint authentication device or a capacitive touch panel for scrolling or the like is not required to be provided separately in the electronic device. Therefore, by using the display device of one embodiment of the present invention, an electronic device with reduced manufacturing costs can be provided.

[0027] In a display device of one embodiment of the present invention, when light emitted from a light-emitting device included in a display portion is reflected (or scattered) by an object, the light-receiving device can detect the reflected light (or scattered light). Therefore, imaging or touch detection is possible even in a dark place.

[0028] The display device of this embodiment has a function of displaying an image using a light-emitting device, that is, the light-emitting device functions as a display device (also referred to as a display element).

[0029] As the light-emitting device, for example, an OLED (organic light-emitting diode) or a QLED (quantum-dot light-emitting diode) is preferably used. Examples of the light-emitting substance (also referred to as a light-emitting material) included in the light-emitting device include a substance that emits fluorescence (fluorescent material), a substance that emits phosphorescence (phosphorescent material), and a substance that exhibits thermally activated delayed fluorescence (thermally activated delayed fluorescence (TADF) material). Furthermore, an LED such as a micro LED (light-emitting diode) can also be used as the light-emitting device. Furthermore, an inorganic compound (for example, a quantum dot material) can also be used as the light-emitting substance included in the light-emitting device.

[0030] The display device of this embodiment mode has a function of detecting light using a light-receiving device.

[0031] When the light receiving device is used as an image sensor, the display device of the present embodiment can capture an image using the light receiving device. For example, the display device of the present embodiment can be used as a scanner.

[0032] For example, data such as fingerprints, palm prints, or irises can be acquired using an image sensor. That is, a biometric authentication sensor can be built into the display device of the present embodiment. 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.

[0033] Furthermore, an image sensor can be used to acquire data such as the user's facial expression, eye movement, or changes in pupil diameter. By analyzing this data, it is possible to acquire information about the user's mind and body. By changing the output content of one or both of the display and audio based on this information, it is possible to ensure the user's safe use of devices, such as VR (Virtual Reality), AR (Augmented Reality), or MR (Mixed Reality).

[0034] Furthermore, when the light receiving device is used as a touch sensor, the display device of the present embodiment can detect the proximity or contact of an object using the light receiving device.

[0035] The light receiving device may be, for example, a pn-type or pin-type photodiode. The light receiving device functions as a photoelectric conversion device (also called a photoelectric conversion element) that detects light incident on the light receiving device and generates electric charges. The amount of electric charges generated is determined based on the amount of incident light.

[0036] In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light-receiving device. Organic photodiodes can be easily made thin, lightweight, and large in area, and have a high degree of freedom in shape and design, making them applicable to a variety of display devices.

[0037] In one embodiment of the present invention, an organic EL device is used as the light-emitting device, and an organic photodiode is used as the light-receiving device. The organic EL device and the organic photodiode can be formed on the same substrate. Therefore, the organic photodiode can be built into a display device using the organic EL device.

[0038] Separately fabricating all layers constituting an organic EL device and an organic photodiode requires a large number of film-forming processes. Because organic photodiodes have many layers that can be configured in common with organic EL devices, the number of film-forming processes can be suppressed by simultaneously depositing the layers that can be configured in common. Furthermore, even if the number of film-forming processes is the same, reducing the number of layers deposited only on some devices can reduce the impact of misalignment of the film-forming pattern and the impact of dust (including small foreign objects called particles) adhering to the film-forming mask (e.g., metal mask). This can increase the yield of display device manufacturing.

[0039] 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 common layer between the light-receiving device and the light-emitting device. This reduces the number of film formation steps and the number of masks, thereby reducing the number of manufacturing steps and manufacturing costs of the display device. Note that a layer common to the light-receiving device and the light-emitting device may have different functions in the light-receiving device and the light-emitting device. In this specification, components are 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 common to the light-receiving device and the light-emitting device may have the same function in the light-emitting device and 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.

[0040] Furthermore, the light-emitting layer of the light-emitting device and the active layer of the light-receiving device can be formed in an island shape using a fine metal mask (also called a metal mask or a shadow mask). When manufacturing a high-definition display device, the edge of the light-emitting layer and the edge of the active layer can overlap each other. By using a fine metal mask, a high-definition display device with a resolution of 300 ppi or more or 500 ppi or more and 1000 ppi or less or 800 ppi or less can be manufactured.

[0041] Furthermore, overlapping of light-emitting layers in light-emitting devices emitting light of different colors can cause side leakage and degrade display quality. For example, when a phosphorescent light-emitting device is used in both a red light-emitting device and a green light-emitting device, the red light-emitting device can have a red light-emitting material dispersed in the same host material, and the green light-emitting device can have a green light-emitting material dispersed in the same host material to form the respective light-emitting layers. When the light-emitting layers have similar structures, side leakage is likely to occur. Therefore, it is preferable to have a structure in which the red light-emitting layer and the green light-emitting layer do not directly contact each other, or to have a structure in which the area of ​​direct contact between the red light-emitting layer and the green light-emitting layer is reduced. Therefore, it is preferable to have a process of forming an active layer between the process of forming the red light-emitting layer and the process of forming the green light-emitting layer. This creates a portion with an active layer between the red light-emitting layer and the green light-emitting layer, thereby reducing the area of ​​direct contact between the red light-emitting layer and the green light-emitting layer. Therefore, side leakage between light-emitting devices emitting light of different colors can be suppressed. As a result, a display device with high display quality can be realized.

[0042] [Configuration Example 1 of Display Device] FIGS. 1A to 1D each illustrate a cross-sectional view of a display device according to one embodiment of the present invention.

[0043] A display device 50A shown in FIG. 1A has, between a substrate 51 and a substrate 59, a layer 53 having a light-receiving device and a layer 57 having a light-emitting device.

[0044] A display device 50B shown in FIG. 1B has, between a substrate 51 and a substrate 59, a layer 53 having a light-receiving device, a layer 55 having a transistor, and a layer 57 having a light-emitting device.

[0045] In the display device 50A and the display device 50B, red (R), green (G), and blue (B) light are emitted from the layer 57 having the light-emitting device.

[0046] A display device according to one embodiment of the present invention includes a plurality of pixels arranged in a matrix. Each pixel includes one or more subpixels. Each subpixel includes one light-emitting device. For example, the pixel may include three subpixels (e.g., three subpixels of R, G, and B, and three subpixels of yellow (Y), cyan (C), and magenta (M)). Alternatively, the pixel may include four subpixels (e.g., four subpixels of R, G, B, and white (W)), four subpixels of R, G, B, and Y, and four subpixels of R, G, B, and infrared (IR)). The pixel may also include a light-receiving device. The light-receiving device may be provided in all or some of the pixels. Furthermore, one pixel may include multiple light-receiving devices.

[0047] The transistor-containing layer 55 preferably includes a first transistor and a second transistor, the first transistor being electrically connected to the light-receiving device, and the second transistor being electrically connected to the light-emitting device.

[0048] The display device according to one embodiment of the present invention may have a function of detecting an object, such as a finger, in contact with the display device. For example, as shown in FIG. 1C , light emitted from a light-emitting device in a layer 57 having a light-emitting device is reflected by a finger 52 in contact with the display device 50B, and the reflected light is detected by a light-receiving device in a layer 53 having a light-receiving device. This allows detection of the finger 52 in contact with the display device 50B.

[0049] The display device according to one aspect of the present invention may have a function of detecting or capturing an image of an object that is close to (i.e., not in contact with) the display device 50B, as shown in FIG. 1D.

[0050] 1E shows an example of a fingerprint image captured by the display device of one embodiment of the present invention. In FIG. 1E, the outline of a finger 220 is indicated by a dashed line within an imaging area 226, and the outline of a contact portion 224 is indicated by a dashed line. Within the contact portion 224, a fingerprint 222 with high contrast can be captured due to differences in the amount of light incident on the light-receiving device.

[0051] [Pixel Layout] The pixel layout of a display device according to one embodiment of the present invention will be described. The arrangement of subpixels included in a pixel is not particularly limited, and various methods can be applied. Examples of the arrangement of subpixels include a stripe arrangement, an S-stripe arrangement, a matrix arrangement, a delta arrangement, a Bayer arrangement, and a pentile arrangement.

[0052] Examples of the top surface shape of a sub-pixel include a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon or a hexagon, shapes of these polygons with rounded corners, an ellipse, a circle, etc. Here, the top surface shape of a sub-pixel corresponds to the top surface shape of the light-emitting region of a light-emitting device or the light-receiving region of a light-receiving device.

[0053] 2A to 2C includes a subpixel G that emits green light, a subpixel B that emits blue light, a subpixel R that emits red light, and a subpixel S that has a light-receiving device. The order in which the subpixels are arranged is not particularly limited. When detecting light of a specific color using the subpixel S, it is preferable to arrange the subpixel that emits light of that color next to the subpixel S, as this increases the detection accuracy. Furthermore, the more reliable the light-emitting device a subpixel has, the smaller its size can be.

[0054] The pixel shown in Fig. 2A has a stripe arrangement. Fig. 2A shows an example in which subpixel R is located between subpixel B and subpixel S, but for example, subpixel R and subpixel G may be adjacent to each other.

[0055] A matrix arrangement is applied to the pixel shown in Fig. 2B. Fig. 2B shows an example in which subpixels R and S are located in the same row, and subpixels B and G are located in the same row, but for example, subpixels R and G or subpixels B may be located in the same row. Similarly, an example in which subpixels R and B are located in the same column, and subpixels S and G are located in the same column, but for example, subpixels R and G or subpixels S may be located in the same column.

[0056] The pixel shown in Fig. 2C has a configuration in which a fourth subpixel is added to the S-stripe arrangement. The pixel in Fig. 2C has a vertically elongated subpixel B and horizontally elongated subpixels R, G, and S. However, the vertically elongated subpixel may be any of the subpixels R, G, and S, and there is no limitation on the arrangement order of the horizontally elongated subpixels.

[0057] 2D shows an example in which pixels 109a and 109b are alternately arranged. Pixel 109a has subpixels B, G, and S, and pixel 109b has subpixels R, G, and S. While FIG. 2D shows an example in which both pixel 109a and pixel 109b have subpixels G and S, this is not particularly limited. Having subpixel S in both pixel 109a and pixel 109b is preferable because it increases the definition of the captured image. In this case, it is preferable to detect light emitted by the subpixel (subpixel G in FIG. 2D) that both pixel 109a and pixel 109b have.

[0058] FIG. 2E shows a modified example in which the sub-pixels of the pixels 109a and 109b shown in FIG. 2D each have a substantially rectangular shape with rounded corners when viewed from above.

[0059] The pixel layout shown in Figure 2F is a two-dimensional hexagonal close-packed type. The hexagonal close-packed type layout is preferable because it increases the aperture ratio of each subpixel. Figure 2F shows an example in which each subpixel has a hexagonal top surface shape.

[0060] FIG. 2G shows a modified example in which the pixel shown in FIG. 2F has a generally hexagonal top view shape with rounded corners.

[0061] In order to form the top surface of the EL layer into a desired shape, a technique for correcting a mask pattern in advance (OPC (Optical Proximity Correction) technique) may be used so that the design pattern and the transfer pattern coincide with each other. Specifically, the OPC technique adds a correction pattern to the corners of figures on the mask pattern.

[0062] The pixel shown in FIG. 2H is an example in which subpixels R, G, and B are arranged in one horizontal row, and subpixel S is arranged below them.

[0063] The pixel shown in FIG. 2I is an example in which subpixels R, G, B, and X are arranged in one horizontal row, and subpixel S is arranged below them.

[0064] The subpixel X may be, for example, a subpixel that emits infrared light (IR). Specifically, the subpixel X may have a configuration including a light-emitting device that emits infrared light (IR). In this case, the subpixel S preferably detects infrared light. For example, while displaying an image using the subpixels R, G, and B, the subpixel X may be used as a light source, and the reflected light of the light emitted by the subpixel X may be detected by the subpixel S.

[0065] As the sub-pixel X, for example, a sub-pixel that emits white (W) light or a sub-pixel that emits yellow (Y) light can be used.

[0066] Furthermore, for example, a configuration including a light receiving device can be applied as the subpixel X. In this case, the wavelength ranges of light detected by the subpixel S and the subpixel X may be the same, different, or partially common. For example, one of the subpixels S and X may mainly detect visible light, and the other may mainly detect infrared light.

[0067] [Sub-pixel S] Using the sub-pixel S, it is possible to capture an image for personal authentication using, for example, a fingerprint, palm print, iris, pulse shape (including vein shape and artery shape), or face.

[0068] The smaller the light receiving area of ​​the subpixel S, the narrower the imaging range, making it possible to suppress blurring of the captured image and improve the resolution.

[0069] The resolution of the subpixel S may be, for example, 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 may be 2000 ppi or less, 1000 ppi or less, or 600 ppi or less. In particular, by positioning the light-receiving device so that the resolution is 200 ppi to 600 ppi, preferably 300 ppi to 600 ppi, it can be suitably used for fingerprint imaging. Furthermore, a resolution of 500 ppi or more is preferable because it complies with standards such as those of the National Institute of Standards and Technology (NIST). Assuming that the resolution of the light-receiving device is 500 ppi, the size per pixel is 50.8 μm, which is sufficient resolution for imaging the width of a fingerprint (typically, 300 μm to 500 μm).

[0070] A clear fingerprint image can be obtained by arranging the light-receiving devices at intervals smaller than the distance between two convex portions of a fingerprint, preferably the distance between adjacent convex and concave portions. The distance between convex and concave portions of a human fingerprint is said to be approximately 200 μm. The width of a human fingerprint is said to be between 300 μm and 500 μm, or 460 μm±150 μm. For example, the interval between the light-receiving devices is 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.

[0071] The light receiving device included in the subpixel S preferably detects visible light, and preferably detects one or more of light of blue, purple, blue-purple, green, yellow-green, yellow, orange, red, etc. The light receiving device included in the subpixel S may also detect infrared light.

[0072] The subpixel S can be used as a touch sensor (also called a direct touch sensor) or a non-contact sensor (also called a hover sensor, hover touch sensor, near touch sensor, or touchless sensor). The wavelength of light to be detected by the subpixel S can be appropriately determined depending on the application. For example, if the subpixel S can detect infrared light, touch detection becomes possible even in a dark place.

[0073] Here, a touch sensor or a non-contact sensor can detect the proximity or contact of an object (such as a finger, a hand, or a pen). A touch sensor can detect an object when an electronic device equipped with a display device according to one embodiment of the present invention is in direct contact with the object. A non-contact sensor can detect an object even when the object does not come into contact with the electronic device. For example, a display device (or an electronic device) is preferably configured to detect an object when the distance between the display device (or the electronic device) and the object is in the range of 0.1 mm to 300 mm, preferably 3 mm to 50 mm. This configuration enables the electronic device to be operated without the object directly touching it, in other words, the display device can be operated in a non-contact (touchless) manner. This configuration reduces the risk of the electronic device being soiled or scratched, or enables the electronic device to be operated without the object directly touching dirt (e.g., dust, viruses, etc.) attached to the electronic device.

[0074] Furthermore, 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 to reduce power consumption. Furthermore, the drive frequency of the touch sensor or the non-contact 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 the non-contact sensor can be set to a frequency higher than 120 Hz (typically 240 Hz). This configuration enables low power consumption and an increased response speed of the touch sensor or the non-contact sensor.

[0075] [Structure Example 2 of Display Device] Hereinafter, detailed structures of a light-emitting device and a light-receiving device included in a display device of one embodiment of the present invention will be described with reference to FIGS.

[0076] 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 the substrate on which the light-emitting device is formed, a bottom emission type that emits light toward the substrate on which the light-emitting device is formed, and a dual emission type that emits light to both sides.

[0077] 3 and 4, a top-emission display device will be described as an example.

[0078] Although the present embodiment mainly describes a display device having a light-emitting device that emits visible light and a light-receiving device that detects visible light, the display device may further include a light-emitting device that emits infrared light. The light-receiving device may have a function of detecting infrared light or a function of detecting both visible light and infrared light.

[0079] FIG. 3 is a top view of a display device according to one embodiment of the present invention.

[0080] 3, the area enclosed by the dotted line corresponds to one pixel. One pixel has a light receiving device 110, a red light emitting device 190R, a green light emitting device 190G, and a blue light emitting device 190B.

[0081] The top surface shapes of the light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B are not particularly limited. A hexagonal close-packed type is applied to the pixel layout shown in FIG. 3 . The hexagonal close-packed type layout is preferable because it can increase the aperture ratio of the light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B. When viewed from above, the light-receiving region of the light-receiving device 110 is rectangular, and the light-emitting regions of the light-emitting devices 190R, 190G, and 190B are each hexagonal.

[0082] In a top view (which can also be said to be a plan view), spacers 219 are provided between the green light emitting device 190G and the blue light emitting device 190B. The positions at which the spacers 219 are provided and the number of spacers 219 can be determined appropriately.

[0083] <Display Device 10A> FIG. 4A shows an example of a cross-sectional view taken along dashed dotted line A1-A2 in FIG. 3, and FIG. 4B shows an example of a cross-sectional view taken along dashed dotted line A3-A4 in FIG.

[0084] As shown in FIGS. 4A and 4B, the display device 10A includes a light receiving device 110, a red light emitting device 190R, a green light emitting device 190G, and a blue light emitting device 190B.

[0085] The light-emitting device 190R includes a pixel electrode 111R, a common layer 112, a light-emitting layer 113R, a common layer 114, and a common electrode 115. The light-emitting layer 113R includes an organic compound that emits red light 21R. In this embodiment, a case will be described as an example in which the pixel electrode 111R functions as an anode and the common electrode 115 functions as a cathode.

[0086] The light-emitting device 190R has a function of emitting red light. Specifically, the light-emitting device 190R is an electroluminescent device that emits light toward the substrate 152 by applying a voltage between the pixel electrode 111R and the common electrode 115 (see red light 21R).

[0087] The light-emitting device 190G includes a pixel electrode 111G, a common layer 112, a light-emitting layer 113G, a common layer 114, and a common electrode 115. The light-emitting layer 113G includes an organic compound that emits green light 21G. The light-emitting device 190G has a function of emitting green light 21G.

[0088] The light-emitting device 190B includes a pixel electrode 111B, a common layer 112, a light-emitting layer 113B, a common layer 114, and a common electrode 115. The light-emitting layer 113B includes an organic compound that emits blue light 21B. The light-emitting device 190B has a function of emitting blue light 21B.

[0089] The light-receiving device 110 has a pixel electrode 111S, a common layer 112, an active layer 113S, a common layer 114, and a common electrode 115. The active layer 113S contains an organic compound. The light-receiving device 110 has a function of detecting visible light. In this embodiment, similar to a light-emitting device, the pixel electrode 111S functions as an anode and the common electrode 115 functions as a cathode. By driving the light-receiving device 110 by applying a reverse bias between the pixel electrode 111S and the common electrode 115, the display device 10A can detect light incident on the light-receiving device 110, generate charges, and extract them as a current.

[0090] The light receiving device 110 has a function of detecting light. Specifically, the light receiving device 110 is a photoelectric conversion device that receives light 22 incident from outside the display device 10B and converts the received light into an electrical signal. The light 22 can also be considered to be light emitted by a light emitting device and reflected by an object. The light 22 may also be incident on the light receiving device 110 via a lens.

[0091] The pixel electrodes 111S, 111R, 111G, and 111B, the common layer 112, the active layer 113S, the light-emitting layers 113R, 113G, and 113B, the common layer 114, and the common electrode 115 may each have a single-layer structure or a laminated structure.

[0092] The common layer 112 can have at least one of a hole injection layer, a hole transport layer, and an electron blocking layer. The function of the common layer 112 in the light-emitting device may differ from that in the light-receiving device 110. For example, when the common layer 112 has a hole injection layer, the 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 110.

[0093] The common layer 114 can have at least one of an electron injection layer, an electron transport layer, and a hole blocking layer. The common layer 114 may have different functions in the light-emitting device and in the light-receiving device 110. For example, when the common layer 114 has an electron injection layer, the 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 110.

[0094] In the display device of this embodiment, an organic compound is used for the active layer 113S of the light-receiving device 110. The layers of the light-receiving device 110 other than the active layer 113S can have a common configuration with the light-emitting device (EL device). Therefore, by simply adding a step of forming the active layer 113S to the manufacturing process of the light-emitting device, the light-receiving device 110 can be formed in parallel with the formation of the light-emitting device. Furthermore, the light-emitting device and the light-receiving device 110 can be formed on the same substrate. Therefore, the light-receiving device 110 can be built into the display device without significantly increasing the number of manufacturing steps.

[0095] In the display device 10A, the light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B have a common configuration, except that the active layer 113S of the light-receiving device 110 and the light-emitting layers (light-emitting layers 113R, 113G, and 113B) of the light-emitting devices 190R, 190G, and 190B are fabricated separately. However, the configuration of the light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B is not limited to this. The light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B may have layers that are fabricated separately from each other, in addition to the active layer 113S and the light-emitting layers (light-emitting layers 113R, 113G, and 113B). It is preferable that the light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B have one or more layers that are used in common (common layers). This allows the light receiving device 110 to be built into the display device without significantly increasing the number of manufacturing steps.

[0096] The display device 10A has a light receiving device 110, a light emitting device 190R, a light emitting device 190G, a light emitting device 190B, a transistor 42S, a transistor 42R, a transistor 42G, a transistor 42B, etc. between a pair of substrates (substrate 151 and substrate 152).

[0097] The pixel electrodes 111S, 111R, 111G, and 111B are located on the insulating layer 214. The pixel electrodes 111S, 111R, 111G, and 111B can be formed using the same material and in the same process, which reduces the manufacturing cost of the display device and simplifies the manufacturing process.

[0098] The ends of the pixel electrodes 111S, 111R, 111G, and 111B are covered with partition walls 216. The pixel electrodes 111S, 111R, 111G, and 111B are electrically insulated (or electrically separated) from one another by the partition walls 216.

[0099] An organic insulating film is suitable for the partition wall 216. 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 partition wall 216 may be a layer that transmits visible light or a layer that blocks visible light. For example, a resin material containing a pigment or dye, or a brown resist material may be used to form a (colored) partition wall that blocks visible light.

[0100] The pixel electrode 111S is electrically connected to the source or drain of the transistor 42S through an opening provided in the insulating layer 214. The pixel electrode 111R is electrically connected to the source or drain of the transistor 42R through an opening provided in the insulating layer 214. Similarly, the pixel electrode 111G is electrically connected to the source or drain of the transistor 42G through an opening provided in the insulating layer 214. The pixel electrode 111B is electrically connected to the source or drain of the transistor 42B through an opening provided in the insulating layer 214.

[0101] The transistors 42R, 42G, 42B, and 42S are in contact with each other on the same layer (substrate 151 in FIGS. 4A and 4B).

[0102] At least a part of the circuit electrically connected to the light-receiving device 110 is preferably formed using the same material and in the same process as the circuit electrically connected to the light-emitting device, which allows the display device to be thinner and the manufacturing process to be simplified compared to when the two circuits are formed separately.

[0103] The light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B are preferably covered with a protective layer 116. In Figures 4A and 4B, the protective layer 116 is provided on and in contact with the common electrode 115. By providing the protective layer 116, impurities such as water can be prevented from entering the light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B, thereby improving the reliability of the light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B. In addition, the protective layer 116 and the substrate 152 are bonded together by an adhesive layer 142.

[0104] A light-shielding layer 158 is provided on the surface of substrate 152 facing substrate 151. Light-shielding layer 158 has openings at positions overlapping with each of light-emitting devices 190R, 190G, and 190B and at a position overlapping with light-receiving device 110. Note that in this specification and the like, a position overlapping with a light-emitting device specifically refers to a position overlapping with a light-emitting region of the light-emitting device. Similarly, a position overlapping with light-receiving device 110 specifically refers to a position overlapping with a light-receiving region of light-receiving device 110.

[0105] On the display surface of the display device of one embodiment of the present invention, light emitted from the light-emitting device is extracted and light irradiated to the light-receiving device passes through. Light emitted from the light-emitting device is preferably extracted to the outside of the display device through the openings in the light-shielding layer 158 (or a region where no light-shielding layer is provided), and light is preferably irradiated onto the light-receiving device through the openings in the light-shielding layer 158 (or a region where no light-shielding layer is provided).

[0106] The light-receiving device 110 detects light emitted from the light-emitting device and reflected by an object. However, there are cases where the light emitted from the light-emitting device is reflected within the display device and enters the light-receiving device 110 as stray light without passing through the object. Such stray light becomes noise during light detection and is a factor in reducing the signal-to-noise ratio (S / N ratio). By providing the light-shielding layer 158, the effects of stray light can be suppressed. This reduces noise and increases the sensitivity of a sensor using the light-receiving device 110.

[0107] The light-shielding layer 158 may be made of a material that blocks light emitted from the light-emitting device. The light-shielding layer 158 preferably absorbs visible light. For example, the light-shielding layer 158 may be made of a black matrix using a metal material or a resin material containing a pigment (such as carbon black) or a dye. The light-shielding layer 158 may have a laminated structure of red, green, and blue color filters.

[0108] The spacer 219 is located on the partition wall 216 and is located between the light emitting device 190G and the light emitting device 190B in a top view.

[0109] As shown in Fig. 4A, the display device 10A has a structure in which an active layer 113S and a light-emitting layer 113R are stacked in this order on a partition wall 216. Although Fig. 4A clearly shows a structure in which the light-emitting layer 113R is provided on the active layer 113S, the present invention is not limited to this. For example, a structure in which the active layer 113S is provided on the light-emitting layer 113R may also be used.

[0110] In the manufacturing process of the display device, a metal mask may come into direct contact with the spacer 219. In this case, the light-emitting layer 113G and the light-emitting layer 113B are not formed on the spacer 219, as shown in FIG.

[0111] <Display device 10B> Fig. 4C shows an example of a cross-sectional view taken along dashed dotted line A1-A2 in Fig. 3. In the following description of the display device, description of the same configuration as the display device described above may be omitted.

[0112] The display device 10B has a light receiving device 110, a light emitting device 190R, a transistor 42S, a transistor 42R, and the like between a pair of substrates (substrate 151 and substrate 152).

[0113] The light-emitting device 190R has a pixel electrode 111R, a functional layer 112R, a light-emitting layer 113R, a functional layer 114R, and a common electrode 115. The light-emitting layer 113R contains an organic compound that emits red light 21R. The light-emitting device 190R has a function of emitting red light.

[0114] The light receiving device 110 includes a pixel electrode 111S, a functional layer 112S, an active layer 113S, a functional layer 114S, and a common electrode 115. The active layer 113S includes an organic compound. The light receiving device 110 has a function of detecting visible light.

[0115] Each of the functional layers 112R, 112S, 114R, and 114S may have a single-layer structure or a laminated structure.

[0116] The functional layer 112S is located on the pixel electrode 111S. The active layer 113S overlaps the pixel electrode 111S via the functional layer 112S. The functional layer 114S is located on the active layer 113S. The active layer 113S overlaps the common electrode 115 via the functional layer 114S. The functional layer 112S may have a hole transport layer. The functional layer 114S may have an electron transport layer.

[0117] The functional layer 112R is located on the pixel electrode 111R. The light-emitting layer 113R overlaps the pixel electrode 111R via the functional layer 112R. The functional layer 114R is located on the light-emitting layer 113R. The light-emitting layer 113R overlaps the common electrode 115 via the functional layer 114R. The functional layer 112R can have at least one of a hole injection layer, a hole transport layer, and an electron blocking layer. The functional layer 114R can have at least one of an electron injection layer, an electron transport layer, and a hole blocking layer.

[0118] The common electrode 115 is a layer that is used in common by the light receiving device 110 and the light emitting device 190R.

[0119] In the light-receiving device 110, the functional layer 112S, active layer 113S, and functional layer 114S, each located between the pixel electrode 111S and the common electrode 115, can also be referred to as organic layers (layers containing an organic compound). The pixel electrode 111S preferably has a function of reflecting visible light. The common electrode 115 has a function of transmitting visible light. Note that, when the light-receiving device 110 detects infrared light, the common electrode 115 has a function of transmitting infrared light. Furthermore, the pixel electrode 111S preferably has a function of reflecting infrared light.

[0120] In the light-emitting device 190R, the functional layer 112R, the light-emitting layer 113R, and the functional layer 114R, which are respectively located between the pixel electrode 111R and the common electrode 115, can also be referred to as EL layers. The pixel electrode 111R preferably has a function of reflecting visible light. The common electrode 115 has a function of transmitting visible light.

[0121] The light-emitting device of the display device of this embodiment preferably has a micro-optical resonator (microcavity) structure. Therefore, one of a pair of electrodes of the light-emitting device preferably has an electrode that is transparent and reflective to visible light (semi-transmissive / semi-reflective electrode), and the other preferably has an electrode that is reflective to visible light (reflective electrode). By having the light-emitting device have a microcavity structure, light emitted from the light-emitting layer can be resonated between both electrodes, thereby intensifying the light emitted from the light-emitting device.

[0122] The semi-transmitting / semi-reflective electrode can have a laminated structure of a reflective electrode and an electrode that is transparent to visible light (also referred to as a transparent electrode). In this specification and the like, the reflective electrode, which functions as a part of the semi-transmitting / semi-reflective electrode, is sometimes referred to as a pixel electrode or a common electrode, and the transparent electrode is sometimes referred to as an optical adjustment layer, but it can also be said that the transparent electrode (optical adjustment layer) functions as a pixel electrode or a common electrode.

[0123] The light transmittance of the transparent electrode is 40% or more. For example, it is preferable to use an electrode with a visible light (light with a wavelength of 400 nm or more and less than 750 nm) transmittance of 40% or more for a light-emitting device. The visible light reflectance of the semi-transmissive / semi-reflective electrode is 10% or more and 95% or less, preferably 30% or more and 80% or less. The visible light reflectance of the reflective electrode is 40% or more and 100% or less, preferably 70% or more and 100% or less. The resistivity of these electrodes is 1×10 −２ When a light-emitting device that emits near-infrared light is used in the display device, the transmittance and reflectance of these electrodes for near-infrared light (light with a wavelength of 750 nm or more and 1300 nm or less) are preferably in the above-mentioned ranges.

[0124] At least one of the functional layers 112R, 112S, 114R, and 114S may function as an optical adjustment layer. By varying the film thickness of the functional layer in each light-emitting device, it is possible to intensify and extract light of a specific color in each light-emitting device. Note that when the semi-transmissive / semi-reflective electrode has a stacked structure of a reflective electrode and a transparent electrode, the optical distance between a pair of electrodes refers to the optical distance between a pair of reflective electrodes.

[0125] The display device 10B has a structure in which a functional layer 112S, an active layer 113S, a functional layer 114S, a functional layer 112R, a light-emitting layer 113R, and a functional layer 114R are stacked in this order on the partition wall 216. The stacking order of these layers is not particularly limited. For example, the functional layer 112S, the functional layer 112R, the active layer 113S, the light-emitting layer 113R, the functional layer 114S, and the functional layer 114R may be stacked in this order. Furthermore, the active layer 113S may be provided on the light-emitting layer 113R.

[0126] [Example of Manufacturing Method of Display Device] Next, an example of a manufacturing method of a display device will be described with reference to Fig. 5 to Fig. 7. Fig. 5A to Fig. 7B mainly describe a manufacturing method for a structure including the light-emitting devices 190R, 190G, and 190B, the light-receiving device 110, and a connection portion between the common electrode 115 and a conductive layer.

[0127] 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.

[0128] Furthermore, thin films (insulating films, semiconductor films, conductive films, etc.) constituting the display device can be formed by methods such as spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, knife coating, etc.

[0129] 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, as well as 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.

[0130] Furthermore, 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.

[0131] 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.

[0132] 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.

[0133] For etching the thin film, dry etching, wet etching, sandblasting, or the like can be used.

[0134] First, a substrate is prepared. The substrate may be a substrate having heat resistance sufficient to withstand at least the subsequent heat treatment. When an insulating substrate is used, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, an organic resin substrate, or the like may be used. Alternatively, a semiconductor substrate such as a single-crystal semiconductor substrate made of silicon, silicon carbide, or the like, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, or an SOI substrate may be used.

[0135] In particular, it is preferable to use a substrate in which a semiconductor circuit including semiconductor elements such as transistors is formed on the semiconductor substrate or insulating substrate. The semiconductor circuit preferably constitutes, for example, a pixel circuit, a gate line driving circuit (gate driver), a source line driving circuit (source driver), etc. In addition to the above, an arithmetic circuit, a memory circuit, etc. may also be configured.

[0136] An insulating layer 105 is provided on the top of the substrate. A plurality of openings reaching transistors, wirings, electrodes, or the like provided on the substrate are provided in the insulating layer 105. The openings can be formed by photolithography.

[0137] The insulating layer 105 can be made of an inorganic insulating material or an organic insulating material.

[0138] Next, a conductive film is formed on the insulating layer 105. The conductive film can be formed by, for example, sputtering or vacuum evaporation. The conductive film is then processed to form the pixel electrodes 111R, 111G, 111B, and 111S and the conductive layer 111C on the insulating layer 105 ( FIG. 5A ). Specifically, a resist mask is formed on the conductive film by photolithography, and unnecessary portions of the conductive film are removed by etching. After that, the resist mask is removed, so that the pixel electrodes 111R, 111G, 111B, and 111S and the conductive layer 111C can be formed in the same process.

[0139] Next, partition walls 216 are formed to cover the ends of the pixel electrodes 111R, 111G, 111B, and 111S and the conductive layer 111C (FIG. 5A).

[0140] The partition wall 216 can have a single layer structure or a multilayer structure using one or both of an inorganic insulating film and an organic insulating film.

[0141] Next, the common layer 112 is formed on the pixel electrodes 111R, 111G, 111B, and 111S (FIG. 5B).

[0142] 5B, the common layer 112 is preferably formed so as not to overlap the conductive layer 111C. For example, the deposition range of the common layer 112 can be controlled by using a mask for defining a deposition area (also referred to as an area mask or a rough metal mask, in distinction from a fine metal mask).

[0143] The common layer 112 can be preferably formed by vacuum deposition, but is not limited thereto, and can also be formed by sputtering, transfer, printing, coating, inkjet, or the like.

[0144] Next, an island-shaped light-emitting layer 113G is formed on the common layer 112 so as to encompass the region overlapping with the pixel electrode 111G.

[0145] The light-emitting layer 113G is preferably formed by vacuum deposition using a fine metal mask (FMM). Alternatively, the island-shaped light-emitting layer 113G may be formed by sputtering using an FMM or by ink-jet printing.

[0146] 5C shows the formation of the light-emitting layer 113G via the FMM 151G, in a so-called face-down method in which the film is formed with the substrate inverted so that the surface to be formed faces downward.

[0147] In a vapor deposition method using an FMM, the deposition is often performed over a wider area than the opening pattern of the FMM, and therefore, as shown by the dashed line in FIG. 5C , the light-emitting layer 113G can be deposited over a wider area than the opening pattern of the FMM 151G.

[0148] Next, using FMM151S, an island-shaped active layer 113S is formed on the common layer 112 so as to encompass the area overlapping with the pixel electrode 111S (FIG. 6A).

[0149] The active layer 113S is formed in a pattern that extends beyond the pixel electrode 111S, similar to the light-emitting layer 113G.

[0150] Next, using FMM151R, an island-shaped light-emitting layer 113R is formed on the common layer 112 so as to encompass the area overlapping with the pixel electrode 111R (FIG. 6B).

[0151] As for the light-emitting layer 113R, a pattern extending beyond the pixel electrode 111R is formed, similar to the light-emitting layer 113G. As a result, as shown in region SR in Fig. 6B, a portion where the light-emitting layer 113R overlaps the active layer 113S is formed. Also, as shown in region GR in Fig. 6B, a portion where the light-emitting layer 113R overlaps the light-emitting layer 113G is formed.

[0152] Next, using the FMM 151B, an island-shaped light-emitting layer 113B is formed on the common layer 112 so as to encompass the area overlapping with the pixel electrode 111B (FIG. 7A).

[0153] As for the light-emitting layer 113B, a pattern extending outward beyond the pixel electrode 111B is formed, similar to the light-emitting layer 113G. As a result, as shown in region SB in Fig. 7A, a portion where the light-emitting layer 113B overlaps the active layer 113S is formed. Also, as shown in region GB in Fig. 7A, a portion where the light-emitting layer 113B overlaps the light-emitting layer 113G is formed.

[0154] The order of deposition of the light-emitting layers 113R, 113G, and 113B and the active layer 113S is not particularly limited. If there is a risk of side leakage occurring due to direct contact between any two of the light-emitting layers 113R, 113G, and 113B, it is preferable to form one of the two layers, then form the active layer 113S, and then form the other of the two layers. This reduces the area where the two layers contact, making it possible to suppress the occurrence of side leakage.

[0155] Next, the common layer 114 is formed on the light-emitting layers 113R, 113G, and 113B and the active layer 113S (FIG. 7B).

[0156] 7B, the common layer 114 is preferably formed so as not to overlap the conductive layer 111C. For example, the deposition range of the common layer 114 can be controlled by using a mask for defining the deposition area.

[0157] The common layer 114 can be preferably formed by vacuum deposition, but is not limited thereto, and can also be formed by sputtering, transfer, printing, coating, inkjet, or the like.

[0158] Next, a common electrode 115 is formed on the common layer 114 (FIG. 7B).

[0159] For example, sputtering or vacuum deposition can be used to form the common electrode 115. Alternatively, a film formed by deposition and a film formed by sputtering may be stacked.

[0160] When forming the common electrode 115, a mask may be used to define the film formation area.

[0161] After that, a protective layer 116 is formed over the common electrode 115 (FIG. 7B). Furthermore, a substrate 152 is attached to the protective layer 116 using an adhesive layer 142, whereby the display device of this embodiment mode can be manufactured.

[0162] Examples of a method for forming the protective layer 116 include a vacuum deposition method, a sputtering method, a CVD method, and an ALD method. The protective layer 116 may be formed by stacking films formed using different film formation methods.

[0163] Display Device Configuration Example 3 A more detailed configuration of a display device of one embodiment of the present invention will be described below with reference to FIGS. 8 to 11B. FIG.

[0164] <Display Device 100A> FIG. 8 shows a perspective view of the display device 100A, and FIG. 9 shows a cross-sectional view of the display device 100A.

[0165] The display device 100A has a configuration in which a substrate 152 and a substrate 151 are bonded together. In Fig. 8, the substrate 152 is clearly indicated by a dashed line.

[0166] The display device 100A includes a display portion 162, a circuit 164, wiring 165, and the like. Fig. 8 shows an example in which an IC (integrated circuit) 173 and an FPC 172 are mounted on the display device 100A. Therefore, the configuration shown in Fig. 8 can also be considered as a display module including the display device 100A, the IC, and the FPC.

[0167] The circuit 164 can be, for example, a scanning line driver circuit.

[0168] 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 input to the wiring 165 from the IC 173.

[0169] 8 shows an example in which an IC 173 is provided on the substrate 151 by a COG method, a COF method, or the like. 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 be configured without an IC. Alternatively, the IC may be mounted on an FPC by a COF method, or the like.

[0170] FIG. 9 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 portion 162, and a part of a region including an end portion are cut away.

[0171] A display device 100A shown in FIG. 9 includes a transistor 201, a transistor 205, a transistor 206, a light-emitting device 190R, a light-receiving device 110, a protective layer 116, and the like between a substrate 151 and a substrate 152.

[0172] The substrate 152 and the protective layer 116 are bonded together by adhesive layers 142a and 142b. A solid sealing structure, a hollow sealing structure, or the like can be applied to seal the light-emitting device 190R and the light-receiving device 110. In FIG. 9, the space surrounded by the substrate 152, the frame-shaped adhesive layer 142b, and the substrate 151 is filled with the adhesive layer 142a, thereby applying a solid sealing structure. It is also possible to bond the substrate 152 and the protective layer 116 together using a single type of adhesive layer without providing a frame-shaped adhesive layer. Alternatively, the space may be filled with an inert gas (such as nitrogen or argon) to apply a hollow sealing structure.

[0173] The light-emitting device 190R has a layered structure in which a pixel electrode 111R, a common layer 112, a light-emitting layer 113R that emits red light, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214 side. The pixel electrode 111R is connected to a conductive layer 222b of the transistor 206 through an opening provided in the insulating layer 214.

[0174] The edge of the pixel electrode 111R is covered with a partition wall 216. The pixel electrode 111R contains a material that reflects visible light, and the common electrode 115 contains a material that transmits visible light.

[0175] The light-receiving device 110 has a layered structure in which a pixel electrode 111S, a common layer 112, an active layer 113S, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214 side. The pixel electrode 111S is electrically connected to a conductive layer 222b of the transistor 205 through an opening provided in the insulating layer 214. An end of the pixel electrode 111S is covered with a partition wall 216. The pixel electrode 111S contains a material that reflects visible light, and the common electrode 115 contains a material that transmits visible light.

[0176] Light emitted from the light-emitting device 190R is emitted toward the substrate 152. Furthermore, light is incident on the light-receiving device 110 via the substrate 152 and the adhesive layer 142a. The substrate 152 is preferably made of a material that is highly transparent to visible light.

[0177] The pixel electrodes 111R and 111S can be manufactured using the same material and the same process. The common layer 112, the common layer 114, and the common electrode 115 are used in both the light-receiving device 110 and the light-emitting device 190R. The light-receiving device 110 and the light-emitting device 190R can have the same configuration except for the configurations of the active layer 113S and the light-emitting layer 113R. This allows the light-receiving device 110 to be built into the display device 100A without significantly increasing the number of manufacturing processes.

[0178] The partition wall 216 covers the end of the pixel electrode 111S and the end of the pixel electrode 111R. On the partition wall 216, there is a region SR where the light-emitting layer 113R and the active layer 113S overlap each other.

[0179] By providing a protective layer 116 that covers the light receiving device 110 and the light emitting device 190R, impurities such as water can be prevented from entering the light receiving device 110 and the light emitting device 190R, thereby improving the reliability of the light receiving device 110 and the light emitting device 190R.

[0180] The transistor 201, the transistor 205, and the transistor 206 are all formed over a substrate 151. These transistors can be manufactured using the same material and through the same process.

[0181] An insulating layer 211, 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 211 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.

[0182] 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 layer. 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.

[0183] It is preferable to use an inorganic insulating film for each of the insulating layers 211, 213, and 215. Examples of inorganic insulating films 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. Further examples include 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. Two or more of the above insulating films may be stacked.

[0184] 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.

[0185] An organic insulating film is suitable for the insulating layer 214 that functions as a planarizing 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 resin, phenol resin, and precursors of these resins.

[0186] 9, an opening is formed in the insulating layer 214. This makes it possible to prevent impurities from entering the display unit 162 from the outside through the insulating layer 214, even when an organic insulating film is used for the insulating layer 214. This makes it possible to improve the reliability of the display device 100A.

[0187] In a region 228 near the edge of the display device 100A, it is preferable that the insulating layer 215 and the protective layer 116 contact each other through the opening in the insulating layer 214. In particular, it is preferable that the inorganic insulating film of the insulating layer 215 and the inorganic insulating film of the protective layer 116 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.

[0188] The protective layer 116 preferably has at least one inorganic insulating film. The protective layer 116 may have a single-layer structure or a laminated structure of two or more layers. For example, the protective layer 116 may have a three-layer structure in which a first inorganic insulating film, an organic insulating film, and a second inorganic insulating film are laminated in this order.

[0189] The transistor 201, the transistor 205, and the transistor 206 each include a conductive layer 221 that functions as a gate, an insulating layer 211 that functions as a gate insulating layer, conductive layers 222a and 222b that function as 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 211 is located between the conductive layer 221 and the semiconductor layer 231. The insulating layer 213 is located between the conductive layer 223 and the semiconductor layer 231.

[0190] 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.

[0191] The transistors 201, 205, and 206 each 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 the same signal may be supplied to drive the transistor. 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 the other.

[0192] The crystallinity of a semiconductor material used for a transistor is not particularly limited, and any of an amorphous semiconductor, a single crystal semiconductor, and a semiconductor having crystallinity other than a single crystal (a microcrystalline semiconductor, a polycrystalline semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a single crystal semiconductor or a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0193] The semiconductor layer of the transistor preferably includes a metal oxide (also referred to as an oxide semiconductor). That is, the display device of this embodiment preferably includes a transistor using a metal oxide for a channel formation region (hereinafter referred to as an OS transistor).

[0194] Examples of crystalline oxide semiconductors include c-axis-aligned crystalline (CAAC)-OS, nanocrystalline (nc)-OS, and the like.

[0195] Alternatively, a transistor using silicon for a channel formation region (Si transistor) may be used. Examples of silicon include single crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, a transistor having low temperature polysilicon (LTPS) in a semiconductor layer (hereinafter also referred to as an LTPS transistor) may be used. An LTPS transistor has high field-effect mobility and favorable frequency characteristics.

[0196] By using Si transistors such as LTPS 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, which simplifies the external circuits mounted on the display device and reduces component and mounting costs.

[0197] An OS transistor has significantly higher field-effect mobility than a transistor using amorphous silicon. Furthermore, an OS transistor has significantly lower source-drain leakage current in an off state (hereinafter also referred to as off-state current), and can hold charge accumulated in a capacitor connected in series with the transistor for a long period of time. Furthermore, the use of an OS transistor can reduce the power consumption of a display device.

[0198] The off-state current of the OS transistor per 1 μm of channel width at room temperature is 1 aA (1×10 −１８ A) Below, 1zA (1×10 −２１ A) or less, or 1 yA (1 x 10 −２４ Note that the off-state current of a Si transistor per 1 μm of channel width at room temperature can be 1 fA (1×10 −１５ A) More than 1pA (1×10 −１２ Therefore, it can be said that the off-state current of an OS transistor is about 10 orders of magnitude lower than that of a Si transistor.

[0199] Furthermore, to increase the emission luminance of a light-emitting device included in a pixel circuit, it is necessary to increase the amount of current flowing through the light-emitting device. To achieve this, it is necessary to increase the source-drain voltage of a driving transistor included in the pixel circuit. Since an OS transistor has a higher source-drain withstand voltage than a Si transistor, a high voltage can be applied between the source and drain of the OS transistor. Therefore, by using an OS transistor as the driving transistor included in a pixel circuit, it is possible to increase the amount of current flowing through the light-emitting device and increase the emission luminance of the light-emitting device.

[0200] Furthermore, when the transistor operates in the saturation region, the OS transistor can reduce the change in source-drain current with respect to a change in gate-source voltage compared to a Si transistor. Therefore, by using an OS transistor as a driving transistor included in a pixel circuit, the current flowing between the source and drain can be precisely controlled by changing the gate-source voltage, thereby controlling the amount of current flowing through the light-emitting device. This allows for a greater number of gray levels to be displayed in the pixel circuit.

[0201] Furthermore, in terms of the saturation characteristics of the current that flows when a transistor operates in the saturation region, an OS transistor can pass a more stable current (saturation current) than a Si transistor, even when the source-drain voltage gradually increases. Therefore, by using an OS transistor as a driving transistor, a stable current can be passed through a light-emitting device, even when the current-voltage characteristics of an EL device vary. In other words, when an OS transistor operates in the saturation region, the source-drain current of the OS transistor remains almost unchanged even when the source-drain voltage increases, thereby stabilizing the light-emitting luminance of the light-emitting device.

[0202] As described above, by using an OS transistor for a driving transistor included in a pixel circuit, it is possible to achieve "suppression of black floating," "increase in light emission luminance," "multiple gradations," "suppression of variations in light-emitting devices," and the like.

[0203] 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.

[0204] 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. Alternatively, it is preferable to use an oxide containing indium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium, gallium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), and zinc (Zn) (also referred to as IAZO). Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), gallium (Ga), and zinc (Zn) (also referred to as IAGZO).

[0205] 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. The atomic ratio of metal elements in such an In-M-Zn oxide may be In:M:Zn=1:1:1 or a composition thereabout, In:M:Zn=1:1:1.2 or a composition thereabout, In:M:Zn=1:3:2 or a composition thereabout, In:M:Zn=1:3:4 or a composition thereabout, In:M:Zn=2:1:3 or a composition thereabout, In:M:Zn=3:1:2 or a composition thereabout, or In:M:Zn=4:2:3. or a composition in the vicinity thereof, In:M:Zn = 4:2:4.1 or a composition in the vicinity thereof, In:M:Zn = 5:1:3 or a composition in the vicinity thereof, In:M:Zn = 5:1:6 or a composition in the vicinity thereof, In:M:Zn = 5:1:7 or a composition in the vicinity thereof, In:M:Zn = 5:1:8 or a composition in the vicinity thereof, In:M:Zn = 6:1:6 or a composition in the vicinity thereof, In:M:Zn = 5:2:5 or a composition in the vicinity thereof, etc. Note that a composition in the vicinity thereof includes a range of ±30% of the desired atomic ratio.

[0206] 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.

[0207] 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.

[0208] All the transistors included in the display portion 162 may be OS transistors, all the transistors included in the display portion 162 may be Si transistors, or some of the transistors included in the display portion 162 may be OS transistors and the rest may be Si transistors.

[0209] For example, by using both an LTPS transistor and an OS transistor in the display portion 162, a display device with low power consumption and high driving capability can be realized. A structure in which an LTPS transistor and an OS transistor are combined is sometimes referred to as LTPO. As a more preferable example, it is preferable to use an OS transistor as a transistor that functions as a switch for controlling conduction / non-conduction between wirings and to use an LTPS transistor as a transistor for controlling current.

[0210] For example, one of the transistors included in the display portion 162 functions as a transistor for controlling a current flowing through a light-emitting device and can also be called a driving transistor. One of the source and drain of the driving transistor is electrically connected to a pixel electrode of the light-emitting device. It is preferable to use an LTPS transistor as the driving transistor. This allows a large current to flow through the light-emitting device in the pixel circuit.

[0211] On the other hand, another transistor included in the display portion 162 functions as a switch for controlling pixel selection / non-selection and can also be called a selection transistor. The gate of the selection transistor is electrically connected to a gate line, and one of the source and drain is electrically connected to a source line (signal line). An OS transistor is preferably used as the selection transistor. This allows the gradation of a pixel to be maintained even when the frame frequency is significantly reduced (for example, 1 fps or less). Therefore, power consumption can be reduced by stopping the driver when displaying a still image.

[0212] As described above, the display device of one embodiment of the present invention can have a high aperture ratio, high definition, high display quality, and low power consumption.

[0213] 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, which is obtained by processing the same conductive film as the pixel electrode 111S, is exposed on the upper 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.

[0214] Various optical members can be disposed on the outside of the 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 scratches caused by use, an impact absorbing layer, etc. may also be disposed on the outside of the substrate 152.

[0215] The substrate 151 and the substrate 152 can each be made of glass, quartz, ceramic, sapphire, resin, or the like. When a flexible material is used for the substrate 151 and the substrate 152, the flexibility of the display device can be increased, and a flexible display can be realized.

[0216] The adhesive layer can be made of various curable adhesives, such as photocurable 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.

[0217] The connection layer 242 may be an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0218] The light-emitting device included in the display device of this embodiment may be any of a top-emission type, a bottom-emission type, and a dual-emission type. A conductive film that transmits visible light is used for an electrode from which light is extracted. In addition, a conductive film that reflects visible light is preferably used for an electrode from which light is not extracted.

[0219] The light-emitting device has at least a light-emitting layer. The light-emitting device may further include a layer other than the light-emitting layer, such as a layer containing a substance with high hole injection properties, a substance with high hole transport properties (hole transport material), a hole blocking material, an electron blocking material, a substance with high electron transport properties (electron transport material), a substance with high electron injection properties, or a bipolar substance (a substance with high electron transport properties and hole transport properties). For example, the common layer 112 preferably includes at least one of a hole injection layer, a hole transport layer, and an electron blocking layer. For example, the common layer 114 preferably includes at least one of a hole blocking layer, an electron transport layer, and an electron injection layer.

[0220] 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).

[0221] 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 transporting material. The hole transporting material is a material having a concentration of 1×10 −６ cm ２ A 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.

[0222] 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 is a material having 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. Examples of electron-transporting materials that can be used include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, and metal complexes having a thiazole skeleton, as well as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives having a quinoline ligand, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and other π-electron-deficient heteroaromatic compounds including nitrogen-containing heteroaromatic compounds.

[0223] The electron injection layer is a layer that injects electrons from the cathode to 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).

[0224] 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 include a first layer made of lithium fluoride and a second layer made of ytterbium.

[0225] 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.

[0226] 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.

[0227] For example, 4,7-diphenyl-1,10-phenanthroline (abbreviation: BPhen), 2,9-di(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen), diquinoxalino[2,3-a:2′,3d′-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.

[0228] Both low molecular weight compounds and high molecular weight compounds may be used, and may contain inorganic compounds, for the common layer 112, the light-emitting layer, and the common layer 114. The layers constituting the common layer 112, the light-emitting layer, and the common layer 114 may 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.

[0229] 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, a substance that emits near-infrared light can also be used as the light-emitting substance.

[0230] The light-receiving device has an active layer that functions as at least a photoelectric conversion layer between a pair of electrodes. In this specification and the like, one of the pair of electrodes may be referred to as a pixel electrode and the other as a common electrode.

[0231] Of the pair of electrodes that a light-receiving device has, one electrode functions as an anode and the other electrode functions as a cathode. The following describes an example in which the pixel electrode functions as the anode and the common electrode functions as the cathode. The light-receiving device can detect light incident on the light-receiving device, generate electric charges, and extract them as a current by applying a reverse bias between the pixel electrode and the common electrode. Alternatively, the pixel electrode may function as a cathode and the common electrode may function as an anode.

[0232] The active layer of the light-receiving device includes a semiconductor. Examples of the semiconductor include inorganic semiconductors such as silicon and organic semiconductors containing organic compounds. In this embodiment, an example in which an organic semiconductor is used as the semiconductor of the active layer is shown. Using an organic semiconductor is preferable because the light-emitting layer and the active layer can be formed by the same method (e.g., vacuum deposition), allowing the use of a common manufacturing device.

[0233] The n-type semiconductor material of the active layer is fullerene (e.g., C ６０ , C ７０Examples of suitable electron-accepting organic semiconductor materials include fullerene derivatives and other electron-accepting organic semiconductor materials. Fullerenes have a soccer ball-like shape, which 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 across 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 π-electron conjugation. High electron-accepting properties allow charge separation to occur quickly and efficiently, making them useful as light-receiving devices. C ６０ , C ７０ Both have a wide absorption band in the visible light region, and C ７０ is C ６０ 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).

[0234] Furthermore, examples of materials for n-type semiconductors include perylene tetracarboxylic acid derivatives such as N,N'-dimethyl-3,4,9,10-perylene tetracarboxylic acid diimide (abbreviation: Me-PTCDI).

[0235] An example of an n-type semiconductor material is 2,2'-(5,5'-(thieno[3,2-b]thiophene-2,5-diyl)bis(thiophene-5,2-diyl))bis(methane-1-yl-1-ylidene)dimalononitrile (abbreviation: FT2TDMN).

[0236] 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.

[0237] Examples of the p-type semiconductor material of the active layer include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanthene (DBP), zinc phthalocyanine (ZnPc), tin phthalocyanine (SnPc), quinacridone, and rubrene.

[0238] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, compounds having an aromatic amine skeleton, etc. 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, rubrene derivatives, tetracene derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, polythiophene derivatives, etc.

[0239] 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.

[0240] 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.

[0241] 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.

[0242] The light-receiving device may further include, as a layer other than the active layer, a layer containing a substance with high hole-transporting properties, a substance with high electron-transporting properties, a bipolar substance (a substance with high electron-transporting properties and high hole-transporting properties), etc. Furthermore, without being limited to the above, the light-receiving device may further include a layer containing a substance with high hole-injecting properties, a hole-blocking material, a substance with high electron-injecting properties, an electron-blocking material, etc.

[0243] The light-receiving device may 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-receiving device may be formed by a method such as vapor deposition (including vacuum deposition), transfer, printing, inkjet printing, or coating.

[0244] For example, the hole transport material or electron blocking material may be a polymer compound such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS), or an inorganic compound such as molybdenum oxide or copper iodide (CuI). The electron transport material or hole blocking material may be an inorganic compound such as zinc oxide (ZnO), or an organic compound such as polyethyleneimine ethoxylate (PEIE). The light-receiving device may have, for example, a mixed film of PEIE and ZnO.

[0245] Furthermore, 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, can be used in the active layer. For example, a method of dispersing an acceptor material in PBDB-T or a PBDB-T derivative can be used.

[0246] The active layer may contain three or more materials. For example, in order to broaden the absorption 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.

[0247] 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.

[0248] 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, and alloy materials containing these metal materials, can be used. Alternatively, nitrides of these 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 thin enough to have light-transmitting properties. A stacked film of the above materials can also be used as a 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 a display device, as well as conductive layers (conductive layers functioning as pixel electrodes or common electrodes) in a display device.

[0249] 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.

[0250] <Display Device 100B> FIGS. 10 and 11A show cross-sectional views of the display device 100B. The perspective view of the display device 100B is similar to that of the display device 100A (FIG. 8). FIG. 10 shows an example of a cross-section of the display device 100B when a portion of a region including the FPC 172, a portion of the circuit 164, and a portion of the display unit 162 are cut away. FIG. 11A shows an example of a cross-section of the display device 100B when a portion of the display unit 162 is cut away. FIG. 10 shows an example of a cross-section of the display unit 162 when a region including the light receiving device 110 and the light emitting device 190R that emits red light is cut away. FIG. 11A shows an example of a cross-section of the display unit 162 when a region including the light emitting device 190G that emits green light and the light emitting device 190B that emits blue light is cut away.

[0251] 10 and 11A includes a transistor 203, a transistor 207, a transistor 208, a transistor 209, a transistor 210, a light-emitting device 190R, a light-emitting device 190G, a light-emitting device 190B, a light-receiving device 110, and the like, between a substrate 153 and a substrate 154. Furthermore, a protective layer may be provided on the light-emitting device 190R, the light-emitting device 190G, the light-emitting device 190B, and the light-receiving device 110.

[0252] The insulating layer 157 and the common electrode 115 are bonded via an adhesive layer 142, and a solid sealing structure is applied to the display device 100B.

[0253] The substrate 153 and the insulating layer 212 are bonded together by an adhesive layer 155. The substrate 154 and the insulating layer 157 are bonded together by an adhesive layer 156.

[0254] The display device 100B is manufactured by first bonding a first fabrication substrate provided with an insulating layer 212, transistors, a light-receiving device 110, a light-emitting device, and the like to a second fabrication substrate provided with an insulating layer 157 and the like with an adhesive layer 142. The first fabrication substrate is then peeled off, and a substrate 153 is attached to the exposed surface. The second fabrication substrate is then peeled off, and a substrate 154 is attached to the exposed surface. Thus, the components formed on the first fabrication substrate and the second fabrication substrate are transferred to the substrates 153 and 154. The substrates 153 and 154 are preferably flexible. This enhances the flexibility of the display device 100B.

[0255] Substrates 153 and 154 may each 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. One or both of substrates 153 and 154 may be made of glass having a thickness sufficient to provide flexibility.

[0256] A film having high optical isotropy may be used for the substrate of the display device of this embodiment. Examples of the film having high optical isotropy include a triacetyl cellulose (TAC, also called cellulose triacetate) film, a cycloolefin polymer (COP) film, a cycloolefin copolymer (COC) film, and an acrylic film.

[0257] The insulating layer 212 and the insulating layer 157 can be formed using the inorganic insulating film that can be used for the insulating layer 211, the insulating layer 213, and the insulating layer 215, respectively.

[0258] The light-emitting device 190R has a layered structure in which a pixel electrode 111R, a common layer 112, a light-emitting layer 113R, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214b side. The pixel electrode 111R is connected to a conductive layer 169R through an opening provided in the insulating layer 214b. The conductive layer 169R is connected to a conductive layer 222b of the transistor 208 through an opening provided in the insulating layer 214a. The conductive layer 222b is connected to a low-resistance region 231n through an opening provided in the insulating layer 215. In other words, the pixel electrode 111R is electrically connected to the transistor 208. The transistor 208 has a function of controlling the driving of the light-emitting device 190R.

[0259] Similarly, the light-emitting device 190G has a layered structure in which a pixel electrode 111G, a common layer 112, a light-emitting layer 113G, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214b side. The pixel electrode 111G is electrically connected to a low-resistance region 231n of the transistor 209 via a conductive layer 169G and a conductive layer 222b of the transistor 209. That is, the pixel electrode 111G is electrically connected to the transistor 209. The transistor 209 has a function of controlling the driving of the light-emitting device 190G.

[0260] The light-emitting device 190B has a layered structure in which the pixel electrode 111B, the common layer 112, the light-emitting layer 113B, the common layer 114, and the common electrode 115 are layered in this order from the insulating layer 214b side. The pixel electrode 111B is electrically connected to the low-resistance region 231n of the transistor 210 via the conductive layer 169B and the conductive layer 222b of the transistor 210. In other words, the pixel electrode 111B is electrically connected to the transistor 210. The transistor 210 has a function of controlling the driving of the light-emitting device 190B.

[0261] The light-receiving device 110 has a layered structure in which a pixel electrode 111S, a common layer 112, an active layer 113S, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214b side. The pixel electrode 111S is electrically connected to a low-resistance region 231n of the transistor 207 via a conductive layer 168 and a conductive layer 222b of the transistor 207. In other words, the pixel electrode 111S is electrically connected to the transistor 207.

[0262] The ends of the pixel electrodes 111S, 111R, 111G, and 111B are covered with partition walls 216. The pixel electrodes 111S, 111R, 111G, and 111B contain a material that reflects visible light, and the common electrode 115 contains a material that transmits visible light.

[0263] On the partition wall 216, there is a region SR where the light-emitting layer 113R and the active layer 113S overlap each other. As shown in Fig. 11A, a spacer 219 is provided on the partition wall 216. A metal mask may come into direct contact with the spacer 219 during the manufacturing process of the display device. In this case, as shown in Fig. 11A, the light-emitting layer 113G and the light-emitting layer 113B are not formed on the spacer 219.

[0264] Light emitted from the light-emitting devices 190R, 190G, and 190B is emitted toward the substrate 154. Light is incident on the light-receiving device 110 via the substrate 154 and the adhesive layer 142. The substrate 154 is preferably made of a material that is highly transparent to visible light.

[0265] The pixel electrodes 111S, 111R, 111G, and 111B can be manufactured using the same material and the same process. The common layer 112, the common layer 114, and the common electrode 115 are used in common for the light-receiving device 110 and the light-emitting devices 190R, 190G, and 190B. The light-receiving device 110 and the light-emitting devices for each color can have the same configuration except for the active layer 113S and the light-emitting layer. This allows the light-receiving device 110 to be built into the display device 100B without significantly increasing the number of manufacturing processes.

[0266] A light-shielding layer may be provided on the surface of the insulating layer 157 facing the substrate 153. By providing the light-shielding layer, the range in which the light-receiving device 110 detects light can be controlled. Furthermore, by providing the light-shielding layer 158, it is possible to prevent light from the light-emitting devices 190R, 190G, and 190B from entering the light-receiving device 110 without passing through the target object. Therefore, a sensor with low noise and high sensitivity can be realized.

[0267] A connection portion 204 is provided in a region of the substrate 153 where the substrate 154 does not overlap. In the connection portion 204, the wiring 165 is electrically connected to the FPC 172 via a conductive layer 167, a conductive layer 166, and a connection layer 242. The conductive layer 167 can be obtained by processing the same conductive film as the conductive layer 168. On the top surface of the connection portion 204, the conductive layer 166, which is obtained by processing the same conductive film as the pixel electrode 111S, is exposed. This allows the connection portion 204 and the FPC 172 to be electrically connected via the connection layer 242.

[0268] The transistor 207, the transistor 208, the transistor 209, and the transistor 210 each include a conductive layer 221 functioning as a gate, an insulating layer 211 functioning as a gate insulating layer, a semiconductor layer 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 211 is located between the conductive layer 221 and the channel formation region 231i. The insulating layer 225 is located between the conductive layer 223 and the channel formation region 231i.

[0269] The conductive layer 222a and the conductive layer 222b are each connected to the low-resistance region 231n through an opening provided in the insulating layer 215. One of the conductive layer 222a and the conductive layer 222b functions as a source, and the other functions as a drain.

[0270] 10, 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. 10. In FIG. 10, 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 each connected to the low-resistance region 231n through openings in the insulating layer 215. Furthermore, a protective layer 116 may be provided to cover the transistor.

[0271] 11B shows an example in which the insulating layer 225 covers the top surface and side surface of the semiconductor layer. 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.

[0272] As described above, the display device of this embodiment has a light-receiving device and a light-emitting device in the display portion, and the display portion has both a function of displaying an image and a function of detecting light. This allows the electronic device to be made smaller and lighter than when a sensor is provided outside the display portion or the display device. Furthermore, by combining the sensor provided outside the display portion or the display device, a more multifunctional electronic device can be realized.

[0273] The light-receiving device may have at least one layer between a pair of electrodes that shares a common structure with the light-emitting device (EL device). For example, all layers of the light-receiving device except for the active layer may share a common structure with the light-emitting device (EL device). In other words, the light-emitting device and the light-receiving device can be formed on the same substrate by simply adding a process for forming an active layer to the process for fabricating the light-emitting device. Furthermore, the pixel electrodes and common electrodes of the light-receiving device and the light-emitting device can be formed using the same material and in the same process. Furthermore, by fabricating the circuit electrically connected to the light-receiving device and the circuit electrically connected to the light-emitting device using the same material and in the same process, the fabrication process for the display device can be simplified. In this way, a highly convenient display device incorporating a light-receiving device can be fabricated without complex processes.

[0274] 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.

[0275] Embodiment 2 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS. 12A and 12B.

[0276] A display device according to one embodiment of the present invention includes a first pixel circuit having a light-receiving device and a second pixel circuit having a light-emitting device, and the first pixel circuit and the second pixel circuit are arranged in a matrix.

[0277] FIG. 12A shows an example of a first pixel circuit having a light-receiving device, and FIG. 12B shows an example of a second pixel circuit having a light-emitting device.

[0278] 12A includes a light receiving device PD, a transistor M1, a transistor M2, a transistor M3, a transistor M4, and a capacitor C1. Here, an example is shown in which a photodiode is used as the light receiving device PD.

[0279] The light-receiving device PD has a cathode electrically connected to a wiring V1 and an anode electrically connected to one of the source and drain of a transistor M1. The transistor M1 has a gate electrically connected to a wiring TX and the other of the source and drain electrically connected to one electrode of a capacitor C1, one of the source and drain of a transistor M2, and the gate of a transistor M3. The transistor M2 has a gate electrically connected to a wiring RES and the other of the source and drain electrically connected to a wiring V2. The transistor M3 has one of the source and drain electrically connected to a wiring V3 and the other of the source and drain electrically connected to one of the source and drain of a transistor M4. The transistor M4 has a gate electrically connected to a wiring SE and the other of the source and drain electrically connected to a wiring OUT1.

[0280] A constant potential is supplied to the wiring V1, the wiring V2, and the wiring V3. When the light-receiving device PD is driven with a reverse bias, a potential lower than the potential of the wiring V1 is supplied to the wiring V2. The transistor M2 is controlled by a signal supplied to the wiring RES and has a function of resetting the potential of a node connected to the gate of the transistor M3 to the potential supplied to the wiring V2. The transistor M1 is controlled by a signal supplied to the wiring TX and has a function of controlling the timing at which the potential of the node changes depending on the current flowing through the light-receiving device PD. The transistor M3 functions as an amplifying transistor that outputs according to the potential of the node. The transistor M4 is controlled by a signal supplied to the wiring SE and functions as a selection transistor that reads out an output according to the potential of the node to an external circuit connected to the wiring OUT1.

[0281] 12B includes a light-emitting device EL, transistors M5, M6, and M7, and a capacitor C2. Here, an example is shown in which a light-emitting diode is used as the light-emitting device EL. It is particularly preferable to use an organic EL device as the light-emitting device EL.

[0282] The gate of the transistor M5 is electrically connected to the wiring VG, one of the source or drain is electrically connected to the wiring VS, and the other of the source or drain is electrically connected to one electrode of the capacitor C2 and the gate of the transistor M6. One of the source or drain of the transistor M6 is electrically connected to the wiring V4, and the other is electrically connected to the anode of the light-emitting device EL and one of the source or drain of the transistor M7. The gate of the transistor M7 is electrically connected to the wiring MS, and the other of the source or drain is electrically connected to the wiring OUT2. The cathode of the light-emitting device EL is electrically connected to the wiring V5.

[0283] A constant potential is supplied to the wiring V4 and the wiring V5. The anode side of the light-emitting device EL can be set to a high potential, and the cathode side can be set to a lower potential than the anode side. The transistor M5 is controlled by a signal supplied to the wiring VG and functions as a selection transistor for controlling the selection state of the pixel circuit PIX2. The transistor M6 also functions as a drive transistor that controls the current flowing through the light-emitting device EL depending on the potential supplied to its gate. When the transistor M5 is in a conductive state, the potential supplied to the wiring VS is supplied to the gate of the transistor M6, and the light emission brightness of the light-emitting device EL can be controlled depending on the potential. The transistor M7 is controlled by a signal supplied to the wiring MS and has the function of outputting the potential between the transistor M6 and the light-emitting device EL to the outside via the wiring OUT2.

[0284] Here, it is preferable that the transistors M1, M2, M3, and M4 included in the pixel circuit PIX1, and the transistors M5, M6, and M7 included in the pixel circuit PIX2 are transistors that use a metal oxide (oxide semiconductor) in a semiconductor layer in which a channel is formed.

[0285] A transistor using a metal oxide, which has a wider band gap and a lower carrier density than silicon, can achieve an extremely small off-state current. Therefore, due to the small off-state current, charge stored in a capacitor connected in series with the transistor can be held for a long period of time. Therefore, it is preferable to use a transistor including an oxide semiconductor for the transistor M1, the transistor M2, and the transistor M5, which are connected in series with the capacitor C1 or the capacitor C2. Furthermore, by using a transistor including an oxide semiconductor for the other transistors as well, manufacturing costs can be reduced.

[0286] Alternatively, the transistors M1 to M7 may be transistors in which silicon is used as a semiconductor in which a channel is formed. In particular, using silicon with high crystallinity, such as single crystal silicon or polycrystalline silicon, is preferable because high field-effect mobility can be achieved and higher-speed operation is possible.

[0287] Alternatively, a structure may be used in which at least one of the transistors M1 to M7 includes an oxide semiconductor and the remaining transistors include silicon.

[0288] Note that although the transistors are shown as n-channel transistors in FIGS. 12A and 12B, p-channel transistors can also be used.

[0289] The transistors of the pixel circuits PIX1 and PIX2 are preferably formed side by side on the same substrate, and in particular, the transistors of the pixel circuits PIX1 and PIX2 are preferably mixed and periodically arranged in one region.

[0290] It is also preferable to provide one or more layers having transistors and / or capacitors at positions overlapping the light receiving device PD or the light emitting device EL, thereby reducing the effective area occupied by each pixel circuit and realizing a high-definition light receiving section or display section.

[0291] This embodiment mode can be combined with other embodiment modes as appropriate.

[0292] Embodiment 3 In this embodiment, electronic devices of one embodiment of the present invention will be described with reference to FIGS. 13A to 16G.

[0293] The electronic device of this embodiment includes the display device of one embodiment of the present invention. For example, the display device of one embodiment of the present invention can be applied to a display portion of the electronic device. The display device of one embodiment of the present invention has a function of detecting light, and therefore, biometric authentication can be performed or a touch operation (contact or proximity) can be detected in the display portion. This can improve the functionality, convenience, and the like of the electronic device.

[0294] Examples of electronic devices include electronic devices with relatively large screens such as television sets, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound playback devices.

[0295] The electronic device of this embodiment may have a sensor (including a function to measure force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays).

[0296] The electronic device of the present embodiment can have various functions, such as a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, time, etc., a function to execute various software (programs), a wireless communication function, a function to read out programs or data recorded on a recording medium, etc.

[0297] The electronic device 6500 shown in FIG. 13A is a portable information terminal that can be used as a smartphone.

[0298] The electronic device 6500 includes a housing 6501, a display portion 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, a light source 6508, and the like. The display portion 6502 has a touch panel function.

[0299] The display device of one embodiment of the present invention can be applied to the display portion 6502 .

[0300] FIG. 13B is a schematic cross-sectional view including the end of the housing 6501 on the microphone 6506 side.

[0301] A light-transmitting protective member 6510 is provided on the display surface side of the housing 6501, and a display panel 6511, optical members 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are arranged in the space surrounded by the housing 6501 and the protective member 6510.

[0302] A display panel 6511, an optical member 6512, and a touch sensor panel 6513 are fixed to the protective member 6510 by adhesive layers (not shown).

[0303] In a region outside the display portion 6502, a part of the display panel 6511 is folded back, and an FPC 6515 is connected to the folded back part. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to a terminal provided on a printed circuit board 6517.

[0304] The flexible display of one embodiment of the present invention can be applied to the display panel 6511. Therefore, an extremely lightweight electronic device can be realized. In addition, since the display panel 6511 is extremely thin, a large-capacity battery 6518 can be mounted thereon while keeping the thickness of the electronic device small. Furthermore, by folding back a part of the display panel 6511 and arranging a connection portion with the FPC 6515 on the back side of the pixel portion, an electronic device with a narrow frame can be realized.

[0305] 14A shows an example of a television set. A television set 7100 has a display portion 7000 built into a housing 7101. Here, the housing 7101 is supported by a stand 7103.

[0306] The display device of one embodiment of the present invention can be applied to the display portion 7000 .

[0307] 14A can be operated using operation switches provided on the housing 7101 and a separate remote control 7111. Alternatively, the display portion 7000 may be provided with a touch sensor, and the television set 7100 may be operated by touching the display portion 7000 with a finger or the like. The remote control 7111 may have a display portion that displays information output from the remote control 7111. Using operation keys or a touch panel provided on the remote control 7111, the channel and volume can be controlled, and an image displayed on the display portion 7000 can be controlled.

[0308] The television device 7100 includes a receiver, a modem, and the like. The receiver can receive general television broadcasts. Furthermore, by connecting to a wired or wireless communication network via the modem, it is possible to perform one-way (from a sender to a receiver) or two-way (between a sender and a receiver, or between receivers, etc.) information communication.

[0309] 14B shows an example of a laptop personal computer 7200. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, an external connection port 7214, and the like. The housing 7211 includes a display portion 7000.

[0310] The display device of one embodiment of the present invention can be applied to the display portion 7000 .

[0311] 14C and 14D show an example of digital signage.

[0312] 14C includes a housing 7301, a display portion 7000, and a speaker 7303. The digital signage 7300 may further include an LED lamp, operation keys (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0313] 14D shows a digital signage 7400 attached to a cylindrical pillar 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.

[0314] 14C and 14D, the display device of one embodiment of the present invention can be applied to the display portion 7000.

[0315] The larger the display unit 7000, the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it will attract people's attention, which can increase the advertising effectiveness of, for example, advertisements.

[0316] Applying a touch panel to the display unit 7000 is preferable because it not only displays images or videos on the display unit 7000 but also allows the user to intuitively operate it. Furthermore, when used to provide information such as route information or traffic information, the intuitive operation can improve usability.

[0317] 14C and 14D , the digital signage 7300 or the digital signage 7400 is preferably capable of wirelessly linking with an information terminal 7311 or an information terminal 7411 such as a smartphone carried by a user. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411. By operating the information terminal 7311 or the information terminal 7411, the display on the display unit 7000 can be switched.

[0318] Furthermore, the digital signage 7300 or the digital signage 7400 can be made to run a game using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller), thereby allowing an unspecified number of users to simultaneously participate in and enjoy the game.

[0319] 15A includes a housing 2801, a housing 2802, a display portion 2803, a keyboard 2804, a pointing device 2805, and the like. A secondary battery 2807 is provided inside the housing 2801, and a secondary battery 2806 is provided inside the housing 2802. The display device of one embodiment of the present invention is applied to the display portion 2803, and the display portion 2803 has a touch panel function. As shown in FIG. 15B, the housing 2801 and the housing 2802 can be removed from the personal computer 2800, and the personal computer 2800 can be used as a tablet terminal using only the housing 2802.

[0320] In a modification of the personal computer shown in Fig. 15C, a flexible display is applied to the display portion 2803. The secondary battery 2806 can be made bendable by using a flexible film for the exterior body. This allows the housing 2802, the display portion 2803, and the secondary battery 2806 to be folded and used as shown in Fig. 15C. In this case, part of the display portion 2803 can also be used as a keyboard as shown in Fig. 15C.

[0321] The housing 2802 can be folded so that the display portion 2803 faces inward as shown in FIG. 15D, or can be folded so that the display portion 2803 faces outward as shown in FIG. 15E.

[0322] The electronic device shown in Figures 16A to 16G has a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), a connection terminal 9006, a sensor 9007 (including a function to measure force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor or infrared rays), a microphone 9008, etc.

[0323] 16A to 16G, the display device of one embodiment of the present invention can be applied to the display portion 9001.

[0324] The electronic devices shown in Figures 16A to 16G have various functions. For example, they may have a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, or time, a function to control processing using various software (programs), a wireless communication function, a function to read and process programs or data recorded on a recording medium, etc. Note that the functions of the electronic devices are not limited to these, and they may have various other functions. The electronic devices may have multiple display units. Furthermore, the electronic devices may have a function to include a camera or the like to capture still images or videos and store them on a recording medium (external or built-in to the camera), a function to display the captured images on a display unit, etc.

[0325] The electronic device shown in FIGS. 16A to 16G will be described in detail below.

[0326] FIG. 16A is a perspective view showing a mobile information terminal 9101. The mobile information terminal 9101 can be used as, for example, a smartphone. Note that the mobile information terminal 9101 may be provided with a speaker 9003, a connection terminal 9006, a sensor 9007, and the like. The mobile information terminal 9101 can display text and image information on multiple surfaces. FIG. 16A shows an example in which three icons 9050 are displayed. Information 9051, indicated by a dashed rectangle, can also be displayed on another surface of the display unit 9001. Examples of the information 9051 include notifications of incoming emails, SNS messages, phone calls, etc., the titles of emails and SNS messages, the sender's name, the date and time, the remaining battery level, and radio wave intensity. Alternatively, an icon 9050 or the like may be displayed in the position where the information 9051 is displayed.

[0327] 16B is a perspective view showing the mobile information terminal 9102. The mobile information terminal 9102 has a function of displaying information on three or more surfaces of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different surfaces. For example, while the user holds the mobile information terminal 9102 in a breast pocket of their clothes, the user can check information 9053 displayed in a position that can be observed from above the mobile information terminal 9102. The user can check the display without taking the mobile information terminal 9102 out of their pocket and decide, for example, whether to answer a call.

[0328] FIG. 16C is a perspective view showing a vehicle steering wheel. The steering wheel 41 includes a rim 42, a hub 43, spokes 44, and a shaft 45. A display unit 20 is provided on the surface of the hub 43. Of the three spokes 44, the lower spoke 44 is provided with a light-emitting / receiving unit 20b, the left spoke 44 is provided with multiple light-emitting / receiving units 20c, and the right spoke 44 is provided with multiple light-emitting / receiving units 20d. By holding the fingers of a hand 35 over the light-emitting / receiving unit 20b, the driver's fingerprint information can be acquired and used for authentication. Furthermore, by touching the light-emitting / receiving units 20c and 20d, the vehicle's navigation system, audio system, and communication system can be operated. Various operations are also possible, such as adjusting the rearview mirror, adjusting the side mirrors, turning the interior lights on and off and adjusting their brightness, and opening and closing the windows.

[0329] FIG. 16D is a perspective view showing a wristwatch-type mobile information terminal 9200. The mobile information terminal 9200 can be used as, for example, a smart watch (registered trademark). The display surface of the display unit 9001 is curved, and display can be performed along the curved display surface. The mobile information terminal 9200 can also perform hands-free calling by communicating with, for example, a headset capable of wireless communication. The mobile information terminal 9200 can also perform data transmission and charging with another information terminal through a connection terminal 9006. Note that charging may be performed by wireless power supply.

[0330] 16E to 16G are perspective views showing a foldable mobile information terminal 9201. Also, FIG. 16E is a perspective view of the mobile information terminal 9201 in an unfolded state, FIG. 16G is a perspective view of the mobile information terminal 9201 in a folded state, and FIG. 16F is a perspective view of a state in the process of changing from one of FIGS. 16E and 16G to the other. The mobile information terminal 9201 is highly portable when folded, and has a seamless, wide display area when unfolded, providing excellent visibility of the display. The display portion 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by hinges 9055. For example, the display portion 9001 can be bent with a curvature radius of 0.1 mm or more and 150 mm or less.

[0331] This embodiment mode can be combined with other embodiment modes and examples as appropriate.

[0332] GB: region, GR: region, MS: wiring, PD: light receiving device, RES: wiring, SB: region, SE: wiring, SR: region, TX: wiring, VG: wiring, VS: wiring, 10A: display device, 10B: display device, 20b: light receiving and emitting unit, 20c: light receiving and emitting unit, 20d: light receiving and emitting unit, 20: display unit, 21B: light, 21G: light, 21R: light, 22: light, 35: hand, 41: handle, 42B: transistor, 42G: transistor, 42R: transistor, 42S: transistor, 42: rim, 43: hub, 44: spoke, 45: shaft, 50A: display device, 50B: display device, 51: substrate, 52: finger, 53: layer, 55: layer, 57: layer, 59: substrate, 100A: display device, 100B: display device, 105: insulating layer, 109a: pixel, 109b: pixel, 110: light receiving device, 111B: pixel electrode, 111C: conductive layer, 111G: pixel electrode, 111R: pixel electrode, 111S: pixel electrode, 112R: functional layer, 112S: functional layer, 112: common layer, 113B: light emitting layer, 113G: light emitting layer, 113R: light emitting layer, 113S: active layer, 114R: functional layer, 114S: functional layer, 114: common layer, 115: common electrode, 116: protective layer, 142a: adhesive layer , 142b: adhesive layer, 142: adhesive layer, 151B: FMM, 151G: FMM, 151R: FMM, 151S: FMM, 151: substrate, 152: substrate, 153: substrate, 154: substrate, 155: adhesive layer, 156: adhesive layer, 157: insulating layer, 158: light-shielding layer, 162: display unit, 164: circuit, 165: wiring, 166: conductive layer, 167: conductive layer, 168: conductive layer, 169B: conductive layer, 169G: conductive layer, 169R: conductive layer, 172: FPC, 173: IC, 190B: light-emitting device, 190G: light-emitting device, 190R: light-emitting device, 201: transistor, 202: transistor, 203: transistor, 204: connection portion, 205: transistor, 206: transistor, 207: transistor, 208: transistor, 209: transistor, 210: transistor, 211: insulating layer, 212: insulating layer, 213: insulating layer, 214a: insulating layer, 214b: insulating layer, 214: insulating layer, 215: insulating layer, 216: partition wall, 219: spacer, 220: finger, 221: conductive layer, 222a: conductive layer, 222b: conductive layer, 222: fingerprint, 223: conductive layer, 224: contact portion, 225: insulating layer, 226: imaging range, 228: area,231i: channel formation region, 231n: low resistance region, 231: semiconductor layer, 242: connection layer, 2800: personal computer, 2801: housing, 2802: housing, 2803: display unit, 2804: keyboard, 2805: pointing device, 2806: secondary battery, 2807: secondary battery, 6500: electronic device, 6501: housing, 6502: display unit, 6503: power button 6504: Button, 6505: Speaker, 6506: Microphone, 6507: Camera, 6508: Light source, 6510: Protective member, 6511: Display panel, 6512: Optical member, 6513: Touch sensor panel, 6515: FPC, 6516: IC, 6517: Printed circuit board, 6518: Battery, 7000: Display unit, 7100: Television device, 7101: Housing, 710 3: stand, 7111: remote control device, 7200: notebook personal computer, 7211: housing, 7212: keyboard, 7213: pointing device, 7214: external connection port, 7300: digital signage, 7301: housing, 7303: speaker, 7311: information terminal, 7400: digital signage, 7401: pillar, 7411: information terminal, 9000: Housing, 9001: Display unit, 9003: Speaker, 9005: Operation keys, 9006: Connection terminal, 9007: Sensor, 9008: Microphone, 9050: Icon, 9051: Information, 9052: Information, 9053: Information, 9054: Information, 9055: Hinge, 9101: Portable information terminal, 9102: Portable information terminal, 9200: Portable information terminal, 9201: Portable information terminal,

Claims

1. A light receiving device and a light emitting device, the light-receiving device includes a first electrode, an insulating layer covering an end of the first electrode, an active layer on the first electrode and the insulating layer, and a second electrode on the active layer; the light-emitting device includes a third electrode, the insulating layer covering an end of the third electrode, a light-emitting layer on the third electrode and the insulating layer, and the second electrode on the light-emitting layer; the active layer and the light emitting layer have a portion that overlaps with each other outside the first electrode and outside the third electrode when viewed from above; a display device, wherein an end of the active layer and an end of the light-emitting layer each have a portion located on the insulating layer.

2. In claim 1, the light receiving device and the light emitting device have a common layer; The display device, wherein the common layer has a portion located between the first electrode and the second electrode, and a portion located between the first electrode and the third electrode.

3. In claim 1 or 2, The light-emitting layer has a portion located above the active layer.

4. a light receiving device, a first light emitting device, and a second light emitting device; the light-receiving device includes a first electrode, an insulating layer covering an end of the first electrode, an active layer on the first electrode and the insulating layer, and a second electrode on the active layer; the first light-emitting device has a third electrode, the insulating layer covering an end of the third electrode, a first light-emitting layer on the third electrode and the insulating layer, and the second electrode on the first light-emitting layer; the second light-emitting device has a fourth electrode, the insulating layer covering an end of the fourth electrode, a second light-emitting layer on the fourth electrode and the insulating layer, and the second electrode on the second light-emitting layer; the first light-emitting layer and the second light-emitting layer have different light-emitting materials; the active layer has a portion located between the first light-emitting layer and the second light-emitting layer in a cross-sectional view; a first end of the first light-emitting layer and a second end of the first light-emitting layer, the first end of the first light-emitting layer and the second end of the first light-emitting layer each having a portion located on the insulating layer.

5. In claim 4, the light receiving device, the first light emitting device, and the second light emitting device have a common layer; the common layer has a portion located between the first electrode and the second electrode, a portion located between the first electrode and the third electrode, and a portion located between the fourth electrode and the third electrode.

6. In any one of claims 1 to 5, A flexible display device.

7. A display module comprising: a display device according to claim 1 ; and at least one of a connector and an integrated circuit.

8. A display module according to claim 7; An electronic device having at least one of a housing, a battery, a camera, a speaker, and a microphone.