Optical Devices

Abstract

Provided is an optical device that has favorable characteristics. Provided is an optical device that has low driving voltage. Provided is an optical device that has low power consumption. This optical device has a first electrode, a second electrode, an active layer, and a carrier transport layer. The active layer is located between the first electrode and the second electrode. The active layer includes a first organic compound and a second organic compound. The first organic compound is represented by general formula (G1), and the second organic compound is represented by general formula (G2-1). The carrier transport layer is located between the second electrode and the active layer. The film thickness of the carrier transport layer is 10-300 nm.

Description

Optical device, display device, and electronic device

[0001] 1. Field of the Invention One aspect of the present invention relates to an optical device and a display device.

[0002] One embodiment of the present invention is not limited to the above technical field, and examples of the technical field of one embodiment of the present invention include 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 used in a variety of devices, including information terminal devices such as smartphones, tablet devices, and laptop PCs, as well as television devices and monitor devices. In addition, there is a demand for display devices that not only display images but also have various additional functions, such as a touch panel function or a function for capturing fingerprint images for authentication.

[0004] As a display device, for example, a light-emitting device having a light-emitting device has been developed. Light-emitting devices (also called EL devices or EL elements) utilizing the electroluminescence (EL) phenomenon have features such as being easily thin and lightweight, being capable of responding quickly to input signals, and being capable of being driven using a DC constant voltage power supply, and are therefore applied to display devices. For example, Patent Document 1 discloses a flexible light-emitting device to which an organic EL device (also called an organic EL element) is applied.

[0005] JP 2014-197522 A

[0006] An object of one embodiment of the present invention is to provide an optical device with favorable characteristics. Another object is to provide an optical device with low driving voltage. Another object is to provide an optical device with low power consumption. Another object is to provide an optical device with high productivity. Another object is to provide an optical device with high convenience. Another object is to provide an optical device with multiple functions. Another object is to provide a novel optical device. Another object is to provide a novel display device. Another object is to provide a novel electronic 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 an optical device including a first electrode, a second electrode, an active layer, and a carrier transport layer. The active layer is located between the first electrode and the second electrode. The active layer includes a first organic compound and a second organic compound, the first organic compound being represented by General Formula (G1), and the second organic compound being represented by General Formula (G2-1). The carrier transport layer is located between the second electrode and the active layer, and the thickness of the carrier transport layer is 10 nm to 300 nm.

[0009]

[0010] In the above general formula (G1), D １ represents a substituted or unsubstituted thiophene-diyl group, a substituted or unsubstituted furan-diyl group, a heteroarylene group having 4 to 30 carbon atoms and containing a substituted or unsubstituted thiophene, or a heteroarylene group having 4 to 30 carbon atoms and containing a substituted or unsubstituted furan; Ar １ and Ar ２ each independently represents a substituted or unsubstituted heteroarylene group having 4 to 30 carbon atoms or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms; A １ and A ２each independently represents hydrogen, deuterium, a nitro group, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a vinyl group having 1 to 3 substituents, and the substituents are cyano groups, halogens, substituted or unsubstituted halogenated alkyl groups having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a nitro group; m １ , n １ , k １ each independently represents an integer of 0 to 3; m １ , n １ , and k １ At least one of represents an integer of 1 to 3.

[0011] In the above general formula (G2-1), R １ ~R １０ each independently represents hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms; m ２ represents an integer of 1 to 5.

[0012] In the above-mentioned optical device, m ２ is 2 or more, and a plurality of R ９ may be different from each other.

[0013] In the above-mentioned optical device, m ２ is 2 or more, and a plurality of R １０ may be different from each other.

[0014] In the above-mentioned optical device, R １ ~R ４ and R ５ ~R ８ At least one pair of adjacent groups may be bonded to each other to form a ring.

[0015] In the above-described optical device, the second organic compound is represented by the structural formula (201) or (202).

[0016]

[0017] One embodiment of the present invention is an optical device including a first electrode, a second electrode, an active layer, and a carrier transport layer. The active layer is located between the first electrode and the second electrode. The active layer includes a first organic compound and a second organic compound, where the first organic compound is represented by General Formula (G1) and the second organic compound is represented by General Formula (G2-2) or Structural Formula (310). The carrier transport layer is located between the second electrode and the active layer, and the thickness of the carrier transport layer is 10 nm to 300 nm.

[0018]

[0019] In the above general formula (G1), D １ represents a substituted or unsubstituted thiophene-diyl group, a substituted or unsubstituted furan-diyl group, a heteroarylene group having 4 to 30 carbon atoms and containing a substituted or unsubstituted thiophene, or a heteroarylene group having 4 to 30 carbon atoms and containing a substituted or unsubstituted furan; Ar １ and Ar ２ each independently represents a substituted or unsubstituted heteroarylene group having 4 to 30 carbon atoms or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms; A １ and A ２ each independently represents hydrogen, deuterium, a nitro group, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a vinyl group having 1 to 3 substituents, and the substituents are cyano groups, halogens, substituted or unsubstituted halogenated alkyl groups having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a nitro group; m １ , n １ , k １ each independently represents an integer of 0 to 3; m １ , n １ , and k １At least one of represents an integer of 1 to 3.

[0020] In the general formula (G2-2), M represents a metal, a metal oxide, or a metal halide; ３ is 1 or 2, and R １１ ~R ２６ each independently represent hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms.

[0021] In the above-described optical device, the second organic compound is represented by any one of structural formulas (301) to (305).

[0022]

[0023] One embodiment of the present invention is an optical device including a first electrode, a second electrode, an active layer, and a carrier-transport layer. The active layer is located between the first electrode and the second electrode. The active layer includes a first organic compound and a second organic compound, where the first organic compound is represented by General Formula (G1) and the second organic compound is represented by General Formula (G2-3). The carrier-transport layer is located between the second electrode and the active layer, and the thickness of the carrier-transport layer is 10 nm to 300 nm.

[0024]

[0025] In the above general formula (G1), D １ represents a substituted or unsubstituted thiophene-diyl group, a substituted or unsubstituted furan-diyl group, a heteroarylene group having 4 to 30 carbon atoms and containing a substituted or unsubstituted thiophene, or a heteroarylene group having 4 to 30 carbon atoms and containing a substituted or unsubstituted furan; Ar １ and Ar ２each independently represents a substituted or unsubstituted heteroarylene group having 4 to 30 carbon atoms or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms; A １ and A ２ each independently represents hydrogen, deuterium, a nitro group, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a vinyl group having 1 to 3 substituents, and the substituents are cyano groups, halogens, substituted or unsubstituted halogenated alkyl groups having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a nitro group; m １ , n １ , k １ each independently represents an integer of 0 to 3; m １ , n １ , and k １ At least one of represents an integer of 1 to 3.

[0026] In the above general formula (G2-3), R ３０ ~R ４９ each independently represent hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms.

[0027] In the optical device, the second organic compound is represented by the structural formula (401).

[0028]

[0029] In the above-mentioned optical device, D １ is represented by any one of general formulas (g1-1-1) to (g1-1-4). １ and Ar ２are each independently a substituted or unsubstituted thiophene-diyl group, a substituted or unsubstituted furan-diyl group, a substituted or unsubstituted phenylene group, or a substituted or unsubstituted naphthalene-diyl group. １ and A ２ are each independently represented by general formula (g1-2).

[0030]

[0031] In the above general formulae (g1-1-1) to (g1-1-4) and (g1-2), R １０１ and R １０２ One of them is Ar １ and Ar ２ and R １０３ and R １０４ One of them is Ar １ and Ar ２ and R １０５ and R １０６ One of them is Ar １ and Ar ２ and R １０７ and R １０８ One of them is Ar １ and Ar ２ and R １０９ and R １１０ One of them is Ar １ and Ar ２ and R １１１ and R １１２ One of them is Ar １ and Ar ２ and R １１３ ~R １１６ One of the two is Ar １ and the other is Ar ２ and R １０１ ~R １１６ the remainders each independently represent hydrogen, deuterium, a linear alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a linear halogenated alkyl group having 1 to 6 carbon atoms, or a halogen; R １１７ ~R１１９ each independently represents hydrogen, deuterium, a cyano group, fluorine, chlorine, a nitro group, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms; R １１７ ~R １１９ at least one of R represents a cyano group, fluorine, chlorine, a nitro group, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms; １２０ is Ar １ and Ar ２ and X １ ~X １４ each independently represents oxygen or sulfur; n １１ represents an integer of 0 to 10, n １２ and n １３ each independently represents an integer of 0 to 4.

[0032] In the optical device described above, the first organic compound is represented by any one of general formulas (G1-1) to (G1-3).

[0033]

[0034] In the above general formulae (G1-1) to (G1-3), X １５ ~X ３０ each independently represents oxygen or sulfur; n １４ and n １７ each independently represents an integer of 0 to 4, １５ , n １６ , n １８ , n １９ 〜n ２２ each independently represents an integer of 0 to 3; ２０ 〜n ２２ At least one of R represents an integer of 1 to 3; １２７ ~R １３２ , and R １３９ ~R １５０each independently represents hydrogen, deuterium, a linear alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a linear halogenated alkyl group having 1 to 6 carbon atoms, or a halogen; R １２１ ~R １２６ , and R １３３ ~R １３８ , and R １６０ ~R １６５ each independently represents hydrogen, deuterium, a cyano group, fluorine, chlorine, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms; R １２１ ~R １２６ and at least one of R １３３ ~R １３８ and at least one of R １６０ ~R １６５ At least one of the groups represents a cyano group, fluorine, chlorine, a nitro group, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms.

[0035] In the optical device described above, the first organic compound is represented by either structural formula (101) or (102).

[0036]

[0037] In the optical device described above, the carrier transport layer comprises an electron transport material.

[0038] The optical device may further include a hole transport layer located between the first electrode and the active layer, the hole transport layer including a hole transport material, and a thickness of the hole transport layer of 10 nm to 300 nm.

[0039] In the optical device described above, the carrier transport layer comprises a hole transport material.

[0040] The optical device may further include an electron transport layer located between the first electrode and the active layer, the electron transport layer including an electron transporting material, and a thickness of the electron transport layer of 10 nm to 300 nm.

[0041] In the optical device described above, the active layer may include a first layer and a second layer, the first layer having a region in contact with the second layer, the first layer including a first organic compound, and the second layer including a second organic compound.

[0042] The optical device may further include a first light-emitting layer located between the first electrode and the active layer.

[0043] The optical device may further include a first light-emitting layer located between the carrier transport layer and the active layer.

[0044] One embodiment of the present invention is a display device including the optical device and a light-emitting device. The light-emitting device includes a third electrode, a second light-emitting layer, and a second electrode. The second light-emitting layer is located between the third electrode and the second electrode, and the second light-emitting layer includes a third organic compound different from the first organic compound.

[0045] The display device may further include at least one of a transistor and a substrate.

[0046] One embodiment of the present invention is an electronic device including the above-described display device and at least one of a microphone, a camera, an operation button, a connection terminal, and a speaker.

[0047] According to one embodiment of the present invention, an optical device with good characteristics can be provided. Alternatively, an optical device with low driving voltage can be provided. Alternatively, an optical device with low power consumption can be provided. Alternatively, an optical device with high productivity can be provided. Alternatively, an optical device with high convenience can be provided. Alternatively, an optical device with multiple functions can be provided. Alternatively, a novel optical device can be provided. Alternatively, a novel display device can be provided. Alternatively, a novel electronic device can be provided.

[0048] 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.

[0049] FIGS. 1A to 1E are cross-sectional views showing an example of a light-receiving device. FIGS. 2A to 2D are cross-sectional views showing an example of a light-receiving and light-emitting device. FIGS. 3A and 3B are cross-sectional views showing an example of a display device. FIGS. 4A and 4B are cross-sectional views showing an example of a display device. FIGS. 5A and 5B are cross-sectional views showing an example of a display device. FIGS. 6A to 6D are cross-sectional views showing an example of a display device. FIGS. 7A to 7D and 7F are cross-sectional views showing an example of a display device. FIGS. 7E and 7G are diagrams showing examples of images captured by the display device. FIGS. 7H to 7K are top views showing an example of a pixel. FIGS. 8A to 8G are top views showing an example of a pixel. FIGS. 9A to 9C are cross-sectional views showing an example of a display device. FIG. 10A is a cross-sectional view showing an example of a display device. FIGS. 10B and 10C are diagrams showing an example of a top surface layout of a resin layer. FIG. 11 is a perspective view showing an example of a display device. FIG. 12 is a cross-sectional view showing an example of a display device. FIG. 13 is a cross-sectional view showing an example of a display device. FIG. 14A is a cross-sectional view showing an example of a display device. FIG. 14B is a cross-sectional view showing an example of a transistor. FIGS. 15A and 15B are circuit diagrams showing an example of a pixel circuit. FIGS. 16A and 16B are diagrams showing an example of an electronic device. FIGS. 17A to 17D are diagrams showing an example of an electronic device. FIGS. 18A to 18F are diagrams showing an example of an electronic device. FIG. 19A is a diagram showing current-voltage characteristics of a light-receiving device. FIG. 19B is a diagram showing external quantum efficiency. FIGS. 20A and 20B are diagrams showing characteristics of a light-receiving device. FIGS. 21A and 21B are diagrams showing current density-voltage characteristics of a light-receiving device. FIGS. 22A and 22B are diagrams showing current density-voltage characteristics of a light-receiving device. FIGS. 23A and 23B are diagrams showing current density-voltage characteristics of a light-receiving device. FIGS. 24A and 24B are diagrams showing current density-voltage characteristics of a light-receiving device. FIGS. 25A and 25B are diagrams showing external quantum efficiency of a light-receiving device. FIGS. 26A and 26B are diagrams showing external quantum efficiency of a light-receiving device. 27A and 27B are graphs showing current density-voltage characteristics of the light-receiving device, and 28A and 28B are graphs showing current density-voltage characteristics of the light-receiving device.29A and 29B are graphs showing current density-voltage characteristics of a light-receiving device. FIGS. 30A and 30B are graphs showing current density-voltage characteristics of a light-receiving device. FIGS. 31A and 31B are graphs showing external quantum efficiency of a light-receiving device. FIGS. 32A and 32B are graphs showing external quantum efficiency of a light-receiving device. FIG. 33 is a graph showing reliability of a light-receiving device.

[0050] 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.

[0051] 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. In addition, when referring to similar functions, the same hatch pattern may be used and no particular reference numeral may be assigned.

[0052] 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.

[0053] It should be noted that the terms "film" and "layer" can be interchangeable depending on the circumstances. For example, the term "conductive layer" can be changed to the term "conductive film." Or, for example, the term "insulating film" can be changed to the term "insulating layer."

[0054] In this embodiment, an optical device according to one embodiment of the present invention will be described. Here, a light-receiving device (also referred to as a light-receiving element) and a light-emitting and receiving device (also referred to as a light-emitting and receiving element) will be described as examples of the optical device.

[0055] <Light-Receiving Device> FIG. 1A shows an example of the configuration of a light-receiving device according to one embodiment of the present invention. FIG. 1A is a cross-sectional view showing the configuration of a light-receiving device 10. The light-receiving device 10 has a first electrode 11, a second electrode 13, and a layer 15 sandwiched between the first electrode 11 and the second electrode 13. The layer 15 has at least an active layer. The light-receiving device 10 can extract, as a current, charges generated by light incident on the active layer. At this time, a voltage may be applied between the first electrode 11 and the second electrode 13. The light-receiving device 10 has the function of detecting visible light or near-infrared light.

[0056] The light-receiving device 10 may have, for example, a pn-type or pin-type photodiode structure. The light-receiving device 10 functions as a photoelectric conversion element (also referred to as a photoelectric conversion device) that detects light incident on the light-receiving device 10 and generates electric charges. The amount of electric charges generated by the light-receiving device 10 is determined based on the amount of light incident on the light-receiving device 10.

[0057] [Active Layer] As shown in FIG. 1B , the light-receiving device 10 can be configured such that the layer 15 includes an active layer 23. The active layer 23 includes a semiconductor. Examples of such semiconductors include inorganic semiconductors such as silicon and organic semiconductors including organic compounds. An organic semiconductor can be suitably used as the semiconductor included in the active layer 23. An organic photodiode having a layer including an organic semiconductor can be suitably used as the light-receiving device 10. Organic photodiodes can be easily made thin, lightweight, and large-area, and also have a high degree of freedom in shape and design, so that the light-receiving device 10 including an organic photodiode can be applied to a variety of devices.

[0058] The active layer 23 includes an n-type semiconductor material and a p-type semiconductor material. The active layer 23 may have a configuration including a mixed layer of the n-type semiconductor material and the p-type semiconductor material (bulk heterojunction structure). For example, the active layer 23 may be formed by co-evaporating the n-type semiconductor material and the p-type semiconductor material. The use of a bulk heterojunction structure allows for an optical device with high photoelectric conversion efficiency.

[0059] An electron-accepting organic semiconductor material can be used as the n-type semiconductor material of the active layer 23. The n-type semiconductor material can be an organic compound represented by general formula (G1).

[0060]

[0061] In general formula (G1), D １ represents a substituted or unsubstituted thiophene-diyl group, a substituted or unsubstituted furan-diyl group, a heteroarylene group having 4 to 30 carbon atoms and containing a substituted or unsubstituted thiophene, or a heteroarylene group having 4 to 30 carbon atoms and containing a substituted or unsubstituted furan; Ar １ and Ar ２ each independently represents a substituted or unsubstituted heteroarylene group having 4 to 30 carbon atoms or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms; A １ and A ２ each independently represents hydrogen, deuterium, a nitro group, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a halogen atom, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a vinyl group having 1 to 3 substituents, and the substituents are cyano groups, halogen atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a nitro group; m １ , n １ , k １ each independently represents an integer of 0 to 3; m １ , n １ , and k １ At least one of represents an integer of 1 to 3.

[0062] In this specification and the like, when a substituted or unsubstituted Z group is referred to, the Z group may be substituted with one or more of deuterium, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, and a halogen. The aryl group or heteroaryl group may be substituted with one or more of deuterium, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, and a halogen.

[0063] m １ When is 2 or 3, multiple Ar １ may all be the same, some may be different, or all may be different. １ If is 2 or 3, multiple D １ may all be the same, some may be different, or all may be different. １ When is 2 or 3, multiple Ar ２ may all be the same, some may be different, or all may be different.

[0064] The organic compound represented by the general formula (G1) has a relatively low boiling point, allowing the deposition temperature to be low. Here, a high deposition temperature may cause deterioration of films formed before the active layer 23, resulting in deterioration of the characteristics of the light-receiving device 10. Furthermore, a high deposition temperature may also cause deterioration of productivity. In one embodiment of the present invention, by using the organic compound represented by the general formula (G1) for the active layer 23, the deterioration of other films can be suppressed, resulting in an optical device with favorable characteristics. Furthermore, the productivity of the light-receiving device 10 can be improved.

[0065] In the above general formula (G1), D １For example, groups represented by the following general formulae (g1-1-1) to (g1-1-4) can be used for A. １ and A ２ For example, a group represented by general formula (g1-2) can be applied to D １ , A １ and A ２ The groups that can be used for are not limited to these.

[0066]

[0067] In general formulae (g1-1-1) to (g1-1-4) and general formula (g1-2), R １０１ and R １０２ One of them is Ar １ and Ar ２ and R １０３ and R １０４ One of them is Ar １ and Ar ２ and R １０５ and R １０６ One of them is Ar １ and Ar ２ and R １０７ and R １０８ One of them is Ar １ and Ar ２ and R １０９ and R １１０ One of them is Ar １ and Ar ２ and R １１１ and R １１２ One of them is Ar １ and Ar ２ and R １１３ ~R １１６ One of the two is Ar １ and the other is Ar ２ and R １０１ ~R １１６the remainders each independently represent hydrogen, deuterium, a linear alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a linear halogenated alkyl group having 1 to 6 carbon atoms, or a halogen; R １１７ ~R １１９ each independently represents hydrogen, deuterium, a cyano group, fluorine, chlorine, a nitro group, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms; R １１７ ~R １１９ at least one of R represents a cyano group, fluorine, chlorine, a nitro group, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms; １２０ is Ar １ and Ar ２ and X １ ~X １４ each independently represents oxygen or sulfur; n １１ represents an integer of 0 to 10, n １２ and n １３ each independently represents an integer of 0 to 4.

[0068] n １１ If there are two or more X ２ Each independently represents oxygen or sulfur. １２ If there are two or more X ５ and multiple X ６ Each independently represents oxygen or sulfur. １３ If there are two or more X ９ and multiple X １０ each independently represents oxygen or sulfur.

[0069] In the above general formula (G1), D １ For example, groups represented by the following structural formulas (D-1) to (D-21), (D-23) to (D-25), and (D-27) to (D-51) can be used. １The groups that can be used as are not limited to these.

[0070]

[0071]

[0072]

[0073]

[0074] The above Ar １ and Ar ２ Examples of the substituted or unsubstituted heteroarylene group having 4 to 30 carbon atoms that can be used as Ar include a substituted or unsubstituted thiophene-diyl group and a substituted or unsubstituted furan-diyl group. １ and Ar ２ Examples of the arylene group having 6 to 30 carbon atoms that can be used as Ar include a substituted or unsubstituted phenylene group and a substituted or unsubstituted naphthalene-diyl group. １ and Ar ２ For example, groups represented by the following structural formulas (Ar-1) to (Ar-10) can be applied to Ar. １ and Ar ２ The groups that can be used for are not limited to these.

[0075]

[0076] In the above general formula (G1), A １ and A ２ For example, groups represented by the following structural formulas (A-1) to (A-25) can be applied to A. １ and A ２ The groups that can be used for are not limited to these.

[0077]

[0078] As a material of the n-type semiconductor included in the active layer 23, an organic compound represented by any one of the general formulas (G1-1) to (G1-3) can be used.

[0079]

[0080] In general formulas (G1-1) to (G1-3), X １５ ~X ３０ each independently represents oxygen or sulfur; n １４ and n １７ each independently represents an integer of 0 to 4, １５ , n １６ , n １８ , n １９ 〜n ２２ each independently represents an integer of 0 to 3; ２０ 〜n ２２ At least one of R represents an integer of 1 to 3; １２７ ~R １３２ , and R １３９ ~R １５０ each independently represents hydrogen, deuterium, a linear alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a linear halogenated alkyl group having 1 to 6 carbon atoms, or a halogen; R １２１ ~R １２６ , and R １３３ ~R １３８ , and R １６０ ~R １６５ each independently represents hydrogen, deuterium, a cyano group, fluorine, chlorine, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms.

[0081] n １４ If there are two or more X １６ and multiple X １７ Each independently represents oxygen or sulfur. １５ 〜n ２２ The same applies when each of X is 2 or more. １８ ~X ３０ When there are plural of any one or more of the following, each independently represents oxygen or sulfur.

[0082] n １５ If there are two or more R １２９may all be the same, some may be different, or all may be different. Similarly, when n15 is 2 or more, a plurality of R １３０ may all be the same, some may be different, or all may be different. １６ , n １８ 〜n ２２ The same applies when each of R is 2 or more. １３１ ~R １５０ When there are a plurality of any one or more of the above, they may all be the same, some may be different, or all may be different.

[0083] Specifically, examples of the n-type semiconductor material of the active layer 23 include organic compounds represented by structural formulas (100) to (137). Note that the organic compound that can be used in one embodiment of the present invention is not limited to these.

[0084]

[0085]

[0086]

[0087] The active layer 273 is made of an n-type semiconductor material, such as fullerene (e.g., C ６０ , C ７０ Examples of electron-accepting organic semiconductor materials include fullerene derivatives and the like. Fullerenes have a soccer ball-like shape, and this shape is energetically stable. Fullerenes have deep (low) HOMO and LUMO levels. Because fullerenes have a deep LUMO level, they have extremely high electron-accepting (acceptor) properties. Normally, when π-electron conjugation (resonance) spreads on a plane, as in benzene, electron-donating (donor) properties increase, but fullerenes have a spherical shape, so they have high electron-accepting properties despite the wide spread of π-electrons. High electron-accepting properties cause charge separation quickly and efficiently, making them useful as light-receiving devices. C ６０ , C ７０ Both have a wide absorption band in the visible light region, and C ７０ is C ６０It is preferred because it has a larger π-electron conjugated system and a wide absorption band in the long wavelength region compared to the above.

[0088] 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.

[0089] An electron-donating organic semiconductor material can be used as the p-type semiconductor material of the active layer 23. The p-type semiconductor material can be an organic compound represented by general formula (G2-1).

[0090]

[0091] In general formula (G2-1), R １ ~R １０ each independently represents hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms; m ２ represents an integer of 1 to 5.

[0092] In addition, R １ ~R ４ and R ５ ~R ８ In the formula, adjacent groups may be bonded to each other to form a ring. ２ If there are two or more R ９ may all be the same, some may be different, or all may be different. ２If there are two or more R １０ may all be the same, some may be different, or all may be different.

[0093] The organic compound represented by the general formula (G2-1) has a relatively low boiling point, and therefore the deposition temperature can be reduced. In one embodiment of the present invention, by using the organic compound represented by the general formula (G2-1) for the active layer 23, deterioration of other films can be suppressed, and the light-receiving device 10 can have favorable characteristics. Furthermore, the productivity of the light-receiving device 10 can be improved.

[0094] In the above general formula (G2-1), R １ ~R １０ For example, groups represented by the following structural formulas (R-1) to (R-78) can be applied to R. １ ~R １０ The groups that can be used as are not limited to these.

[0095]

[0096]

[0097]

[0098] Specifically, examples of the p-type semiconductor material of the active layer 23 include organic compounds represented by structural formulas (201) to (216). Note that the organic compound that can be used in one embodiment of the present invention is not limited to these.

[0099]

[0100]

[0101] An electron-donating organic semiconductor material can be used as the p-type semiconductor material of the active layer 23. The p-type semiconductor material can be an organic compound represented by general formula (G2-2) or structural formula (310).

[0102]

[0103] In general formula (G2-2), M represents a metal, a metal oxide, or a metal halide; ３is 1 or 2, and R １１ ~R ２６ each independently represents hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms.

[0104] The organic compound represented by the general formula (G2-2) or the structural formula (310) has a relatively low boiling point, allowing for a low deposition temperature. In one embodiment of the present invention, by using the organic compound represented by the general formula (G2-2) or the structural formula (310) for the active layer 23, deterioration of other films can be suppressed, resulting in an optical device with favorable characteristics. Furthermore, the productivity of the light-receiving device 10 can be improved.

[0105] Examples of R11 to R26 include groups represented by the structural formulas (R-1) to (R-78) described above.

[0106] Specifically, examples of the p-type semiconductor material of the active layer 23 include organic compounds represented by structural formulas (301) to (313). Note that the organic compound that can be used in one embodiment of the present invention is not limited to these.

[0107]

[0108]

[0109] An electron-donating organic semiconductor material can be used as the p-type semiconductor material of the active layer 23. The p-type semiconductor material can be an organic compound represented by general formula (G2-3).

[0110]

[0111] In general formula (G2-3), R ３０ ~R ４９each independently represents hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms.

[0112] The organic compound represented by the general formula (G2-3) has a relatively low boiling point, allowing the deposition temperature to be low. In one embodiment of the present invention, by using the organic compound represented by the general formula (G2-3) for the active layer 23, deterioration of other films can be suppressed, resulting in a light-receiving device with favorable characteristics. Furthermore, the productivity of the light-receiving device 10 can be improved.

[0113] Examples of R30 to R49 include groups represented by the structural formulae (R-1) to (R-78).

[0114] Specifically, examples of the p-type semiconductor material of the active layer 23 include organic compounds represented by structural formulas (401) to (403). Note that the organic compound that can be used in one embodiment of the present invention is not limited to these.

[0115]

[0116] Examples of the p-type semiconductor material of the active layer 23 include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanthene (DBP), zinc phthalocyanine (ZnPc), tin phthalocyanine (SnPc), and quinacridone.

[0117] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, compounds having an aromatic amine skeleton, etc. Further examples of p-type semiconductor materials include naphthalene derivatives, anthracene derivatives, pyrene derivatives, triphenylene derivatives, fluorene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, indole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, indolocarbazole derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, quinacridone derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, polythiophene derivatives, etc.

[0118] 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.

[0119] 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.

[0120] By including an organic compound represented by general formula (G1) and an organic compound represented by general formula (G2-1), general formula (G2-2), general formula (G2-3), or structural formula (310) in the active layer 23, the active layer 23 is less susceptible to the influence of the material and thickness of the hole transport layer 21 and the material and thickness of the electron transport layer 25, which will be described later, and the driving voltage of the light-receiving device can be reduced. Furthermore, a highly reliable light-receiving device can be realized. This allows for a wider range of materials to be selected for the light-receiving device, thereby increasing the degree of freedom in device design.

[0121] [Carrier Transport Layer] In the light-receiving device 10, the layer 15 may include a carrier transport layer. The carrier transport layer is a layer containing a carrier transport material. The light-receiving device 10 shown in FIG. 1B illustrates an example in which the carrier transport layer includes a hole transport layer 21 and an electron transport layer 25. The light-receiving device 10 shown in FIG. 1B has a structure in which the hole transport layer 21, the active layer 23, and the electron transport layer 25 are stacked in this order on the first electrode 11. The hole transport layer 21, the active layer 23, and the electron transport layer 25 may each have a single-layer structure or a stacked structure. Note that FIG. 1B illustrates an example in which the light-receiving device 10 includes the hole transport layer 21 and the electron transport layer 25, but one embodiment of the present invention is not limited thereto. The light-receiving device 10 may also have a configuration in which only one of the hole transport layer 21 or the electron transport layer 25 is included.

[0122] In the light-receiving device 10, the hole transport layer 21 is a layer that transports holes generated by light incident on the active layer 23 to the anode. The hole transport layer 21 is a layer that contains a hole transport material. −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. The hole transporting material is preferably a material 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).

[0123] The thickness of the hole transport layer 21 is preferably 5 nm to 500 nm, more preferably 10 nm to 400 nm, even more preferably 10 nm to 300 nm, and even more preferably 10 nm to 200 nm.

[0124] Increasing the thickness of the hole transport layer 21 may increase the driving voltage of the light-receiving device 10, resulting in increased power consumption. The light-receiving device 10 according to one embodiment of the present invention can suppress an increase in driving voltage even when the thickness of the hole transport layer 21 is increased. Therefore, the light-receiving device can consume less power. Furthermore, by setting the thickness of the hole transport layer 21 within the above-described range, the light-receiving device can have good characteristics and consume less power.

[0125] The drive voltage of the light-receiving device 10 is preferably -5V or more and 5V or less, more preferably -4V or more and 4V or less, even more preferably -3V or more and 3V or less, even more preferably -2V or more and 2V or less, and even more preferably -1V or more and 1V or less. The drive voltage of the light-receiving device 10 is preferably as close to 0V as possible. The drive voltage can be, for example, a voltage that causes a current of a certain value or more to flow. For example, the drive voltage can be a voltage that causes a current of 20 nA or more to flow.

[0126] In the light-receiving device 10, the electron transport layer 25 is a layer that transports electrons generated by light incident on the active layer 23 to the cathode. The electron transport layer 25 is a layer that contains an electron transport material. The electron transport material has a concentration of 1×10 −６ cm ２ A substance having an electron mobility of 1 / 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 the electron-transporting material 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.

[0127] The film thickness of the electron transport layer 25 is preferably 5 nm to 500 nm, more preferably 10 nm to 400 nm, even more preferably 10 nm to 300 nm, and even more preferably 20 nm to 300 nm.

[0128] Increasing the thickness of the electron transport layer 25 may increase the driving voltage of the light-receiving device 10, resulting in increased power consumption. The light-receiving device 10 according to one embodiment of the present invention can suppress an increase in driving voltage even when the thickness of the electron transport layer 25 is increased. Therefore, the light-receiving device can consume less power. Furthermore, by setting the thickness of the electron transport layer 25 within the above-described range, the light-receiving device can have good characteristics and consume less power.

[0129] [First Electrode, Second Electrode] A conductive film that transmits visible light is used for the electrode on the light-incident side of the first electrode 11 and the second electrode 13. It is preferable to use a conductive film that reflects visible light for the electrode on the side from which light is not extracted. In Figure 1A and other figures, light incident on the light-receiving device 10 is schematically shown by a hollow arrow, using an example of a light-receiving device 10 in which a conductive film that transmits visible light is used for the second electrode 13.

[0130] 1A and the like, the case where the first electrode 11 functions as an anode and the second electrode 13 functions as a cathode has been described as an example, but one embodiment of the present invention is not limited thereto. The first electrode 11 may function as a cathode and the second electrode 13 may function as an anode. In this case, the stacking order of the hole transport layer 21, the active layer 23, and the electron transport layer 25 is reversed.

[0131] As shown in FIG. 1C , the active layer 23 may have a laminated structure of a first layer 23a and a second layer 23b. The first layer 23a has a region in contact with the second layer 23b and is located between the first electrode 11 and the second layer 23b. FIG. 1C illustrates an example in which the first layer 23a is provided on the side of the first electrode 11, which functions as an anode, and the second layer 23b is provided on the side of the second electrode 13, which functions as a cathode. The first layer 23a may have a p-type semiconductor material, and the second layer 23b may have an n-type semiconductor material (bilayer structure). For example, the first layer 23a may be made of a p-type semiconductor material that can be used for the active layer 23 described above. The second layer 23b may be made of an n-type semiconductor material that can be used for the active layer 23 described above. The use of a bilayer structure may reduce leakage current. Therefore, an optical device with a high signal-to-noise ratio may be obtained. The structure (bulk heterojunction structure or bilayer structure) applied to the active layer 23 may be appropriately selected. Furthermore, the active layer 23 may have a structure other than the bulk heterojunction structure or the bilayer structure.

[0132] 1D , the light-receiving device 10 may have a hole transport layer 21 having a stacked structure of a layer 21 a and a layer 21 b on the layer 21 a, and a layer 25 b on the layer 25 a.

[0133] As shown in FIG. 1E, the light-receiving device 10 may have a hole transport layer 21, an electron transport layer 25, and an active layer 23 each having a stacked structure.

[0134] <Light-emitting and receiving device> Fig. 2A shows an example of the configuration of a light-emitting and receiving device according to one embodiment of the present invention. Fig. 2A is a cross-sectional view showing the configuration of a light-emitting and receiving device 10A. The light-emitting and receiving device 10A has a first electrode 11, a second electrode 13, and a layer 15 sandwiched between the first electrode 11 and the second electrode 13. The layer 15 has at least an active layer 23 and a light-emitting layer 39.

[0135] The light emitting and receiving device 10A has both a light emitting function (light emitting function) and a light receiving function (light receiving function). The light emitting and receiving device 10A can detect light with a shorter wavelength than the light it emits. In Figure 2A and other figures, the light incident on the light emitting and receiving device 10A and the light emitted from the light emitting and receiving device 10A are schematically shown by white arrows, using the light emitting and receiving device 10A in which a conductive film that transmits visible light is used as the second electrode 13 as an example.

[0136] The light emitting and receiving device 10A can be fabricated by combining an organic EL element and an organic photodiode. For example, the light emitting and receiving device 10A can be fabricated by adding a light emitting layer 39 to the light receiving device 10 described above. The light emitting and receiving device 10A can prevent an increase in the number of film formation steps by simultaneously forming layers that can be used in common for the organic EL element and the organic photodiode.

[0137] Organic EL elements can be easily made into thin, lightweight, and large-area devices, and there is a high degree of freedom in shape and design, so the light emitting and receiving device 10A using organic EL elements can be applied to a variety of devices.

[0138] 2A , the layer 15 includes a hole injection layer 31, a hole transport layer 21, an active layer 23, a light-emitting layer 39, an electron transport layer 25, and an electron injection layer 35. The light-emitting and receiving device 10A has a structure in which the hole injection layer 31, the hole transport layer 21, the active layer 23, the light-emitting layer 39, the electron transport layer 25, and the electron injection layer 35 are stacked in this order on the first electrode 11. The hole injection layer 31, the hole transport layer 21, the active layer 23, the light-emitting layer 39, the electron transport layer 25, and the electron injection layer 35 may each have a single-layer structure or a stacked structure.

[0139] [Light-emitting layer] The light-emitting layer 39 is a layer containing a light-emitting substance. The light-emitting layer 39 can contain one or more light-emitting substances. As the light-emitting substance, a substance that emits light of a color such as blue, purple, blue-purple, green, yellow-green, yellow, orange, or red is appropriately used. Furthermore, as the light-emitting substance, a substance that emits near-infrared light can also be used.

[0140] Examples of the light-emitting substance include fluorescent materials, phosphorescent materials, thermally activated delayed fluorescence (TADF) materials, and quantum dot materials.

[0141] Examples of fluorescent materials include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives.

[0142] Examples of phosphorescent materials include organometallic complexes (particularly iridium complexes) having a 4H-triazole skeleton, a 1H-triazole skeleton, an imidazole skeleton, a pyrimidine skeleton, a pyrazine skeleton, or a pyridine skeleton; organometallic complexes (particularly iridium complexes) having a phenylpyridine derivative having an electron-withdrawing group as a ligand; platinum complexes; and rare earth metal complexes.

[0143] The light-emitting layer 39 may contain one or more organic compounds (host materials, assist materials, etc.) in addition to a light-emitting substance (guest material). One or both of a hole-transporting material and an electron-transporting material may be used as the one or more organic compounds. Furthermore, a bipolar material or a TADF material may be used as the one or more organic compounds.

[0144] The light-emitting layer 39 preferably includes, for example, a phosphorescent material and a hole-transporting material and an electron-transporting material that are a combination that easily forms an exciplex. This configuration allows for efficient emission using Exciplex-Triple Energy Transfer (ExTET), which is energy transfer from the exciplex to the light-emitting material (phosphorescent material). Selecting a combination that forms an exciplex that emits light that overlaps with the wavelength of the lowest-energy absorption band of the light-emitting material ensures smooth energy transfer and efficient emission. This configuration allows for high efficiency, low-voltage operation, and a long life of the light-receiving and light-emitting device 10A.

[0145] In a combination of materials that form an exciplex, the HOMO level (highest occupied molecular orbital level) of the hole-transporting material is preferably equal to or higher than the HOMO level of the electron-transporting material. The LUMO level (lowest unoccupied molecular orbital level) of the hole-transporting material is preferably equal to or higher than the LUMO level of the electron-transporting material. The LUMO level and HOMO level of the material can be derived from the electrochemical properties (reduction potential and oxidation potential) of the material measured by cyclic voltammetry (CV).

[0146] The formation of exciplexes can be confirmed, for example, by comparing the emission spectra of the hole-transporting material, the electron-transporting material, and a mixed film obtained by mixing these materials, and observing the phenomenon in which the emission spectrum of the mixed film is shifted to longer wavelengths than the emission spectra of each material (or has a new peak at longer wavelengths). Alternatively, the formation of exciplexes can be confirmed by comparing the transient photoluminescence (PL) of the hole-transporting material, the transient PL of the electron-transporting material, and a mixed film obtained by mixing these materials, and observing differences in transient response, such as the transient PL lifetime of the mixed film having a longer-lifetime component or a larger proportion of delayed components than the transient PL lifetimes of the individual materials. The above-mentioned transient PL may also be interpreted as transient electroluminescence (EL). That is, the formation of exciplexes can also be confirmed by comparing the transient EL of the hole-transporting material, the transient EL of the electron-transporting material, and a mixed film obtained by mixing these materials, and observing the differences in transient response.

[0147] The hole injection layer 31 is a layer that injects holes from the first electrode 11 to the hole transport layer 21 and is a layer containing a material with high hole injection properties. As the material with high hole injection properties, an aromatic amine compound or a composite material containing a hole transport material and an acceptor material (electron accepting material) can be used.

[0148] The electron injection layer 35 is a layer that injects electrons from the second electrode 13 into the electron transport layer 25 and is a layer containing a material with high electron injection properties. Examples of the material with high electron injection properties include alkali metals, alkaline earth metals, and compounds thereof. Examples of the material with high electron injection properties include a composite material containing an electron transport material and a donor material (electron donor material).

[0149] The layers of the light-emitting and receiving device 10A may have different functions when the device functions as a light-receiving device and when it functions as a light-emitting device. In this specification, components may be referred to based on their functions when the device functions as a light-emitting device. For example, the hole injection layer functions as a hole injection layer when the device functions as a light-emitting device, and functions as a hole transport layer when the device functions as a light-receiving device. Similarly, the electron injection layer functions as an electron injection layer when the device functions as a light-emitting device, and functions as an electron transport layer when the device functions as a light-receiving device. Furthermore, the layers of the light-emitting and receiving device may have the same functions when the device functions as a light-receiving device and when it functions as a light-emitting device. The hole transport layer functions as a hole transport layer when the device functions as both a light-emitting device and a light-receiving device, and the electron transport layer functions as an electron transport layer when the device functions as both a light-emitting device and a light-receiving device.

[0150] For example, when the light-receiving and light-emitting device 10A functions as a light-receiving device, the hole injection layer 31 functions as a hole transport layer, and when it functions as a light-emitting device, the hole injection layer 31 functions as a hole injection layer. When the light-receiving and light-emitting device 10A functions as a light-receiving device, the electron injection layer 35 functions as an electron transport layer, and when it functions as a light-emitting device, the electron injection layer 35 functions as an electron injection layer.

[0151] 1D and other drawings, the layer 21a may be made of a material that can be used for the hole injection layer 31. The layer 25b may be made of a material that can be used for the electron injection layer 35.

[0152] As shown in FIG. 2B , the light emitting and receiving device 10A may have a structure in which a hole injection layer 31, a hole transport layer 21, a light emitting layer 39, an active layer 23, an electron transport layer 25, and an electron injection layer 35 are stacked in this order on the first electrode 11.

[0153] 2C and 2D, the active layer 23 may have a laminated structure of a first layer 23a and a second layer 23b. The above description can be referred to for the first layer 23a and the second layer 23b, and therefore detailed description thereof will be omitted.

[0154] When the active layer 23 contains an organic compound represented by general formula (G1) and an organic compound represented by general formula (G2-1), general formula (G2-2), or general formula (G2-3), the active layer 23 is less susceptible to the influence of the material and thickness of the hole transport layer 21 and the material and thickness of the electron transport layer 25, and the driving voltage of the light-emitting and receiving device can be reduced. Furthermore, a highly reliable light-emitting and receiving device can be realized. This allows for a wider range of materials to be selected for the light-emitting and receiving device, thereby increasing the degree of freedom in device design.

[0155] This embodiment mode can be combined with other embodiment modes as appropriate.

[0156] Embodiment 2 In this embodiment, a display device which is one embodiment of the present invention will be described.

[0157] A display device according to one embodiment of the present invention includes a light-receiving device and a light-emitting device (also referred to as a light-emitting element). One or both of the light-receiving device and the light-emitting and receiving device described in Embodiment 1 can be suitably used in the display device according to one embodiment of the present invention.

[0158] A display device according to one embodiment of the present invention has a function of detecting light using a light-receiving device. The light-receiving device can be used as an image sensor. For example, the display device can capture an image using the light-receiving device. For example, the display device described in this embodiment can be used as a scanner.

[0159] For example, data related to biometric information such as a fingerprint or palm print can be acquired using an image sensor. That is, a biometric authentication sensor can be built into the display device according to one embodiment of the present invention. By building a biometric authentication sensor into the display device, the number of components in an electronic device can be reduced compared to when a biometric authentication sensor is provided separately from the display device, and a compact and lightweight electronic device can be realized.

[0160] The light-receiving device can be used as, for example, a touch sensor. The display device described in this embodiment can detect a touch operation of an object by using the light-receiving device.

[0161] The light-emitting device preferably uses an EL element (also referred to as an EL device) such as an OLED (organic light-emitting diode) or a QLED (quantum-dot light-emitting diode). Examples of light-emitting materials contained in the EL element include fluorescent materials, phosphorescent materials, inorganic compounds (quantum dot materials, etc.), and thermally activated delayed fluorescence (TADF) materials. Alternatively, an LED such as a micro LED (light-emitting diode) can be used as the light-emitting device.

[0162] In one embodiment of the present invention, an organic EL element (also referred to as an organic EL device) can be used as a light-emitting device, and an organic photodiode can be used as a light-receiving device. The organic EL element 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 element.

[0163] Separately fabricating all layers constituting an organic EL element and an organic photodiode requires an extremely large number of film-forming steps. Since organic photodiodes have many layers that can be configured in common with organic EL elements, the number of layers that can be configured in common can be formed simultaneously, thereby suppressing the increase in film-forming steps.

[0164] For example, one of the pair of electrodes (common electrode) can be a layer common to the light-receiving device and the light-emitting device. It is also preferable to use at least one of the hole injection layer, hole transport layer, electron transport layer, and electron injection layer as a layer common to the light-receiving device and the light-emitting device. Furthermore, the light-receiving device and the light-emitting device can have the same configuration, except that the light-receiving device has an active layer and the light-emitting device has an emitting layer. In other words, a light-receiving device can be fabricated simply by replacing the emitting layer of the emitting device with an active layer. By having a common layer between the light-receiving device and the light-emitting device, the number of film formations and the number of masks can be reduced, thereby reducing the manufacturing process and manufacturing costs of the display device. Furthermore, a display device having a light-receiving device can be fabricated using existing manufacturing equipment and methods for display devices.

[0165] Note that a layer shared by a light-receiving device and a light-emitting device may have different functions in the light-emitting device and in the light-receiving device. In this specification, components may be named based on their functions in the light-emitting device. For example, a hole injection layer functions as a hole injection layer in the light-emitting device and as a hole transport layer in the light-receiving device. Similarly, an electron injection layer functions as an electron injection layer in the light-emitting device and as an electron transport layer in the light-receiving device. Furthermore, a layer shared by a light-receiving device and a light-emitting device may have the same function in the light-emitting device and in the light-receiving device. A hole transport layer functions as a hole transport layer in both the light-emitting device and the light-receiving device, and an electron transport layer functions as an electron transport layer in both the light-emitting device and the light-receiving device.

[0166] Next, a display device having a light receiving and emitting device will be described.

[0167] In a display device according to one embodiment of the present invention, subpixels that exhibit one color have light-emitting and receiving devices instead of light-emitting devices, and subpixels that exhibit the other colors have light-emitting devices. The light-emitting and receiving devices have both a function of emitting light (light-emitting function) and a function of receiving light (light-receiving function). For example, when a pixel has three subpixels, i.e., a red subpixel, a green subpixel, and a blue subpixel, at least one subpixel has a light-emitting and receiving device, and the other subpixels have light-emitting devices. Therefore, the display portion of the display device according to one embodiment of the present invention has a function of displaying an image using both the light-emitting and receiving devices and the light-emitting devices.

[0168] The light-receiving and light-emitting device can serve as both a light-emitting device and a light-receiving device, thereby imparting a light-receiving function to a pixel without increasing the number of subpixels included in the pixel. This allows one or both of an imaging function and a sensing function to be added to the display portion of the display device while maintaining the aperture ratio of the pixel (aperture ratio of each subpixel) and the resolution of the display device. Therefore, the display device of one embodiment of the present invention can have a higher pixel aperture ratio and can easily achieve higher resolution than a display device in which subpixels having light-receiving devices are provided separately from subpixels having light-emitting devices.

[0169] In a display device according to one embodiment of the present invention, a light-emitting and receiving device and a light-emitting device are arranged in a matrix in a display portion, and an image can be displayed on the display portion. The display portion can be used as an image sensor or a touch sensor. In the display device according to one embodiment of the present invention, the light-emitting device can be used as a light source for a sensor. Therefore, a light-receiving portion and a light source are not required separately from the display device, and the number of components in an electronic device can be reduced.

[0170] 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). This makes it possible to capture an image or detect a touch operation even in a dark place.

[0171] A light-emitting and receiving device can be fabricated by combining an organic EL element and an organic photodiode. For example, a light-emitting and receiving device can be fabricated by adding an active layer of an organic photodiode to the layered structure of an organic EL element. Furthermore, a light-emitting and receiving device fabricated by combining an organic EL element and an organic photodiode can suppress an increase in the number of film formation steps by simultaneously forming layers that can be configured in common with the organic EL element.

[0172] For example, one of the pair of electrodes (common electrode) can be a layer common to the light-receiving and light-emitting device. It is also preferable that at least one of the hole injection layer, hole transport layer, electron transport layer, and electron injection layer be a layer common to the light-receiving and light-emitting device. Furthermore, the light-receiving and light-emitting device can have the same configuration as the light-emitting device, except for the presence or absence of an active layer of the light-receiving device. In other words, the light-receiving and light-emitting device can be fabricated simply by adding the active layer of the light-receiving device to the light-emitting device. By having the light-receiving and light-emitting device and the light-emitting device share a common layer, the number of film formations and the number of masks can be reduced, thereby reducing the manufacturing process and manufacturing costs of the display device. Furthermore, a display device having a light-receiving and light-emitting device can be fabricated using existing manufacturing equipment and methods for display devices.

[0173] The display device of this embodiment has a function of displaying an image using a light-emitting device and a light-receiving and light-emitting device, that is, the light-emitting device and the light-receiving and light-emitting device function as display elements.

[0174] The display device of this embodiment has a function of detecting light using a light-receiving and light-emitting device, which can detect light having a shorter wavelength than light emitted by the light-receiving and light-emitting device itself.

[0175] When the light emitting and receiving device is used as an image sensor, the display device of this embodiment can capture an image using the light emitting and receiving device. For example, the display device of this embodiment can be used as a scanner.

[0176] When the light emitting and receiving device is used as a touch sensor, the display device of this embodiment can detect a touch operation of an object using the light emitting and receiving device.

[0177] The light emitting / receiving device functions as a photoelectric conversion element that detects light incident on the light emitting / receiving device and generates electric charges. The amount of electric charges generated by the light emitting / receiving device is determined based on the amount of light incident on the light emitting / receiving device.

[0178] A light-receiving and light-emitting device can be fabricated by adding an active layer of a light-receiving device to the above-described light-emitting device configuration.

[0179] The light emitting / receiving device may be, for example, an active layer of a pn-type or pin-type photodiode.

[0180] In particular, it is preferable to use an organic photodiode active layer having a layer containing an organic compound for the light-receiving and light-emitting device. Organic photodiodes can be easily made thin, lightweight, and large in area, and have a high degree of freedom in shape and design, so light-receiving and light-emitting devices having organic photodiodes can be applied to a variety of devices.

[0181] The structure of a display device according to one embodiment of the present invention will be described.

[0182] 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.

[0183] In this embodiment, a top-emission display device will be described as an example.

[0184] <Configuration Example 1 of Display Device> A configuration example of a display device according to one embodiment of the present invention is shown in Fig. 3A. Fig. 3A is a cross-sectional view showing a configuration example of a display device 280A. Display device 280A shown in Fig. 3A includes a light-receiving device 270PD, a light-emitting device 270R that emits red (R) light, a light-emitting device 270G that emits green (G) light, and a light-emitting device 270B that emits blue (B) light.

[0185] The light receiving device 270PD is a photoelectric conversion element that receives light incident from outside the display device 280A and converts it into an electrical signal.

[0186] The light receiving device 270PD has a first electrode 271, a hole injection layer 281, a hole transport layer 282, an active layer 273, an electron transport layer 284, an electron injection layer 285, and a second electrode 275 stacked in this order.

[0187] The light-receiving device 270PD can have the same configuration as the light-receiving device 10 shown in embodiment 1. In the light-receiving device 270PD, the first electrode 271 corresponds to the first electrode 11 of the light-receiving device 10 shown in embodiment 1. The hole injection layer 281 corresponds to layer 21a. The hole transport layer 282 corresponds to layer 21b. The active layer 273 corresponds to the active layer 23. The electron transport layer 284 corresponds to layer 25a. The electron injection layer 285 corresponds to layer 25b. The second electrode 275 corresponds to the second electrode 13.

[0188] The light-emitting device 270 is an electroluminescent device that emits light toward the second electrode 275 when a voltage is applied between the first electrode 271 and the second electrode 275 .

[0189] Each light-emitting device 270 has a first electrode 271, a hole injection layer 281, a hole transport layer 282, a light-emitting layer, an electron transport layer 284, an electron injection layer 285, and a second electrode 275 stacked in this order. The light-emitting device 270R has a light-emitting layer 283R, the light-emitting device 270G has a light-emitting layer 283G, and the light-emitting device 270B has a light-emitting layer 283B. The light-emitting layer 283R contains a light-emitting material that emits red light, the light-emitting layer 283G contains a light-emitting material that emits green light, and the light-emitting layer 283B contains a light-emitting material that emits blue light. For example, the first electrode 271 functions as a pixel electrode, and the second electrode 275 functions as a common electrode.

[0190] In this specification, unless otherwise specified, even when describing a configuration having multiple elements (e.g., light-emitting devices, light-emitting layers), when describing matters common to each element, the alphabet will be omitted. For example, when describing matters common to light-emitting device 270R and light-emitting device 270G, etc., the term "light-emitting device 270" may be used. When describing matters common to light-emitting layer 283R and light-emitting layer 283G, etc., the term "light-emitting layer 283" may be used.

[0191] In the present embodiment, in both the light-emitting device 270 and the light-receiving device 270PD, the first electrode 271 functions as an anode and the second electrode 275 functions as a cathode. In other words, the light-receiving device 270PD is driven by applying a reverse bias between the first electrode 271 and the second electrode 275, so that it can detect light incident on the light-receiving device 270PD, generate electric charges, and extract the electric charges as a current.

[0192] In the display device of this embodiment, an organic compound is used for the active layer 273 of the light-receiving device 270PD. The layers of the light-receiving device 270PD other than the active layer 273 can have a common configuration with the light-emitting device 270. Therefore, by simply adding a step of forming the active layer 273 to the manufacturing process of the light-emitting device 270, the light-receiving device 270PD can be formed in parallel with the formation of the light-emitting device 270. Furthermore, the light-emitting device 270 and the light-receiving device 270PD can be formed on the same substrate. Therefore, the light-receiving device 270PD can be built into the display device without significantly increasing the number of manufacturing steps.

[0193] It is particularly preferable to use an organic semiconductor as the semiconductor contained in the active layer 273. By using an organic semiconductor, the light-emitting layer 283 and the active layer 273 can be formed by the same method (for example, vacuum deposition), and a common manufacturing device can be used.

[0194] In the display device 280A, the light-receiving device 270PD and the light-emitting device 270 have a common configuration, except that the active layer 273 of the light-receiving device 270PD and the light-emitting layer 283 of the light-emitting device 270 are fabricated separately. However, the configuration of the light-receiving device 270PD and the light-emitting device 270 is not limited to this. The light-receiving device 270PD and the light-emitting device 270 may have layers that are fabricated separately from each other, in addition to the active layer 273 and the light-emitting layer 283. It is preferable that the light-receiving device 270PD and the light-emitting device 270 have one or more layers that are used in common (common layers). This allows the light-receiving device 270PD to be incorporated into the display device without significantly increasing the number of fabrication steps.

[0195] The light-emitting device 270 of the display device 280A preferably has a micro-optical resonator (microcavity) structure. Therefore, one of the pair of electrodes of the light-emitting device 270 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 the two electrodes, thereby intensifying the light emitted from the light-emitting device.

[0196] 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 called a transparent electrode).

[0197] 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-transparent / 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 −２When the light-emitting device emits near-infrared light (light having a wavelength of 750 nm or more and 1300 nm or less), the transmittance or reflectance of these electrodes for near-infrared light preferably satisfies the above-mentioned numerical range, similar to the transmittance or reflectance for visible light.

[0198] The light-emitting device 270 has at least a light-emitting layer 283. The light-emitting device 270 may further have, as a layer other than the light-emitting layer 283, a layer containing a substance with high hole-injection properties, a substance with high hole-transport properties, a hole-blocking material, a substance with high electron-transport properties, a substance with high electron-injection properties, a bipolar substance (a substance with high electron-transport properties and high hole-transport properties), or the like.

[0199] For example, the light-emitting device 270 and the light-receiving device 270PD may have one or more common layers among the hole injection layer, hole transport layer, electron transport layer, and electron injection layer, or the light-emitting device 270 and the light-receiving device 270PD may have one or more different layers among the hole injection layer, hole transport layer, electron transport layer, and electron injection layer.

[0200] The hole injection layer is a layer that injects holes from the anode into the hole transport layer and contains a material with high hole injection properties, such as an aromatic amine compound or a composite material containing a hole transport material and an acceptor material (electron acceptor material).

[0201] In the light-emitting device 270, the hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light-emitting layer.

[0202] The thickness of the hole transport layer 282 is preferably 5 nm to 500 nm, more preferably 10 nm to 400 nm, even more preferably 10 nm to 300 nm, and even more preferably 10 nm to 200 nm.

[0203] In a light-receiving device, increasing the thickness of the hole-transport layer 282 may increase the driving voltage of the light-receiving device 270PD, resulting in increased power consumption. Furthermore, increasing the power consumption of the light-receiving device 270PD may increase the power consumption of the display device 280A. The light-receiving device 270PD, which is one embodiment of the present invention, can suppress an increase in driving voltage even when the thickness of the hole-transport layer 282 is increased. Therefore, a light-receiving device with low power consumption can be obtained. Furthermore, by setting the thickness of the hole-transport layer 282 within the above-described range, a light-receiving device with good characteristics and low power consumption can be obtained. Therefore, a display device with good characteristics and low power consumption can be obtained.

[0204] For example, the optical path length (cavity length) of the microcavity structure can be adjusted by using the film thickness of the hole transport layer 282. In the light-receiving device according to one embodiment of the present invention, an increase in drive voltage can be suppressed even when the film thickness of the hole transport layer 282 is increased, and therefore, the optical path length (cavity length) can be adjusted while maintaining low power consumption.

[0205] In the light-emitting device 270, the electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light-emitting layer.

[0206] The film thickness of the electron transport layer 284 is preferably 5 nm to 500 nm, more preferably 10 nm to 400 nm, even more preferably 10 nm to 300 nm, and even more preferably 20 nm to 300 nm.

[0207] In the light-receiving device, increasing the thickness of the electron transport layer 284 may increase the driving voltage of the light-receiving device 270PD, resulting in increased power consumption. Furthermore, increasing the power consumption of the light-receiving device 270PD may increase the power consumption of the display device 280A. The light-receiving device 270PD, which is one embodiment of the present invention, can suppress an increase in driving voltage even when the thickness of the electron transport layer 284 is increased. Therefore, a light-receiving device with low power consumption can be obtained. Furthermore, by setting the thickness of the electron transport layer 284 within the above range, a light-receiving device with good characteristics and low power consumption can be obtained. Therefore, a display device with good characteristics and low power consumption can be obtained.

[0208] The electron injection layer is a layer that injects electrons from the cathode to the electron transport layer and contains a material with high electron injection properties. Examples of the material with high electron injection properties include alkali metals, alkaline earth metals, and compounds thereof. Examples of the material with high electron injection properties include a composite material containing an electron transport material and a donor material (electron donor material).

[0209] <Configuration Example 2 of Display Device> Fig. 3B shows a configuration different from that of display device 280A shown in Fig. 3A. Display device 280B shown in Fig. 3B mainly differs from display device 280A in that electron transport layer 284 has a stacked structure of first electron transport layer 284a and second electron transport layer 284b. First electron transport layer 284a is located on the active layer 273 side, and second electron transport layer 284b is located on the electron injection layer 285 side.

[0210] 3B shows an example in which the electron-transport layer 284 has a two-layer structure including the first electron-transport layer 284 a and the second electron-transport layer 284 b; however, one embodiment of the present invention is not limited to this. The electron-transport layer 284 may have a stacked structure of three or more layers, and each of the first electron-transport layer 284 a and the second electron-transport layer 284 b may have a stacked structure.

[0211] <Configuration Example 3 of Display Device> Fig. 4A shows a configuration different from that of display device 280A shown in Fig. 3A. Display device 280C shown in Fig. 4A mainly differs from display device 280A in that light-receiving device 270PD and light-emitting device 270R have the same configuration.

[0212] The light receiving device 270PD and the light emitting device 270R have in common an active layer 273 and a light emitting layer 283R.

[0213] Here, it is preferable that the light receiving device 270PD has a common configuration with a light emitting device that emits light of a longer wavelength than the light to be detected. For example, the light receiving device 270PD configured to detect blue light can have a similar configuration to one or both of the light emitting device 270R and the light emitting device 270G. For example, the light receiving device 270PD configured to detect green light can have a similar configuration to the light emitting device 270R.

[0214] By using a common configuration for the light-receiving device 270PD and the light-emitting device 270R, the number of film-forming steps and the number of masks can be reduced compared to a configuration in which the light-receiving device 270PD and the light-emitting device 270R have separate layers, thereby reducing the manufacturing steps and manufacturing costs of the display device.

[0215] The configuration of the light receiving and emitting device 10A described in the first embodiment can be applied to one or more of the light receiving device 270PD and the light emitting device 270R. The configuration of the light receiving and emitting device 10A may be applied to both the light receiving device 270PD and the light emitting device 270R.

[0216] By using a common structure for the light-receiving device 270PD and the light-emitting device 270R, the margin for misalignment can be narrowed compared to a structure in which the light-receiving device 270PD and the light-emitting device 270R have separate layers. This can increase the pixel aperture ratio and improve the light extraction efficiency of the display device. This can extend the life of the light-emitting device. Furthermore, the display device can achieve high luminance. Furthermore, by using the display device according to one embodiment of the present invention, a high-definition display device can be realized.

[0217] The light-emitting layer 283R includes a light-emitting material that emits red light. The active layer 273 includes an organic compound that absorbs light with wavelengths shorter than red (e.g., one or both of green light and blue light). The active layer 273 preferably includes an organic compound that does not easily absorb red light and absorbs light with wavelengths shorter than red. This allows red light to be extracted efficiently from the light-emitting device 270R, and the light-receiving device 270PD to detect light with wavelengths shorter than red with high accuracy.

[0218] In the display device 280C, an example is shown in which the light emitting device 270R and the light receiving device 270PD have the same configuration, but the light emitting device 270R and the light receiving device 270PD may have optical adjustment layers of different thicknesses.

[0219] <Configuration Example 4 of Display Device> Fig. 4B shows a configuration different from that of display device 280C shown in Fig. 4A. Display device 280D shown in Fig. 4B mainly differs from display device 280A in that electron transport layer 284 has a stacked structure of first electron transport layer 284a and second electron transport layer 284b.

[0220] The first electron transport layer 284a and the second electron transport layer 284b can be described in the above-mentioned description, and therefore detailed description thereof will be omitted.

[0221] 4A and 4B illustrate examples in which the active layer 273 is provided on the first electrode 281 side and the light-emitting layer 283R is provided on the second electrode 275 side, but one embodiment of the present invention is not limited to this. A structure different from the display device 280C is shown in FIG. 5A . A structure different from the display device 280D is shown in FIG. 5B . The display devices 280E and 280F differ mainly from the display devices 280C and 280D in the structures of the active layer 273 and the light-emitting layer 283R.

[0222] The display device 280E and the display device 280F have a light-emitting layer 283R on the first electrode 281 side and an active layer 273 on the second electrode 275 side.

[0223] <Configuration Example 6 of Display Device> Figures 6A and 6B show a configuration different from that of display device 280A shown in Figure 3A. Display device 280G shown in Figures 6A and 6B has a light receiving and emitting device 270RPD that emits red (R) light and has a light receiving function, a light emitting device 270G that emits green (G) light, and a light emitting device 270B that emits blue (B) light.

[0224] Each light-emitting device has a first electrode 271, a hole injection layer 281, a hole transport layer 282, a light-emitting layer, an electron transport layer 284, an electron injection layer 285, and a second electrode 275 stacked in this order. Light-emitting device 270G has a light-emitting layer 283G, and light-emitting device 270B has a light-emitting layer 283B. Light-emitting layer 283G contains a light-emitting substance that emits green light, and light-emitting layer 283B contains a light-emitting substance that emits blue light.

[0225] The light emitting and receiving device 270RPD has a first electrode 271, a hole injection layer 281, a hole transport layer 282, an active layer 273, a light emitting layer 283R, an electron transport layer 284, an electron injection layer 285, and a second electrode 275 stacked in this order.

[0226] The light receiving and emitting device 270RPD of the display device 280G has the same configuration as the light emitting device 270R and the light receiving device 270PD of the display device 280C. The light emitting devices 270G and 270B of the display device 280G also have the same configuration as the light emitting devices 270G and 270B of the display device 280C.

[0227] 6A shows a case where the light emitting and receiving device 270RPD functions as a light emitting device, in which the light emitting device 270B emits blue light, the light emitting device 270G emits green light, and the light emitting and receiving device 270RPD emits red light.

[0228] 6B shows a case where the light emitting and receiving device 270RPD functions as a light receiving device, in which the light emitting and receiving device 270RPD detects blue light emitted by the light emitting device 270B and green light emitted by the light emitting device 270G.

[0229] The light-emitting device 270B, the light-emitting device 270G, and the light-receiving and light-emitting device 270RPD each have a first electrode 271 and a second electrode 275. In this embodiment, a case where the first electrode 271 functions as an anode and the second electrode 275 functions as a cathode will be described as an example.

[0230] In this embodiment, similarly to the light-emitting device, the light-receiving and light-emitting device 270RPD will be described as having the first electrode 271 function as an anode and the second electrode 275 function as a cathode. In other words, the light-receiving and light-emitting device 270RPD can detect light incident on the light-receiving and light-emitting device 270RPD, generate electric charges, and extract the electric charges as a current by driving the light-receiving and light-emitting device 270RPD by applying a reverse bias between the first electrode 271 and the second electrode 275.

[0231] 6A and 6B can be considered to have a configuration in which an active layer 273 is added to a light-emitting device. In other words, the light-emitting and receiving device 270RPD can be formed in parallel with the formation of the light-emitting device by simply adding a step of forming the active layer 273 to the manufacturing process of the light-emitting device. Furthermore, the light-emitting device and the light-emitting and receiving device can be formed on the same substrate. Therefore, it is possible to provide the display unit with either or both of an imaging function and a sensing function without significantly increasing the number of manufacturing processes.

[0232] 6A and 6B show an example in which the active layer 273 is provided on the hole transport layer 282, and the light emitting layer 283R is provided on the active layer 273. The light emitting layer 283R may be provided on the hole transport layer 282, and the active layer 273 may be provided on the light emitting layer 283R.

[0233] 6A and 6B , the active layer 273 and the light-emitting layer 283R may be in contact with each other. Alternatively, a buffer layer may be sandwiched between the active layer 273 and the light-emitting layer 283R. The buffer layer may be at least one layer selected from a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a hole blocking layer, an electron blocking layer, and the like.

[0234] By providing a buffer layer between the active layer 273 and the light-emitting layer 283R, it is possible to suppress the transfer of excitation energy from the light-emitting layer 283R to the active layer 273. In addition, the buffer layer can also be used to adjust the optical path length (cavity length) of the microcavity structure. Therefore, a light-emitting / receiving device having a buffer layer between the active layer 273 and the light-emitting layer 283R can achieve high light-emitting efficiency.

[0235] The light emitting and receiving device may not have at least one layer selected from the hole injection layer 281, the hole transport layer 282, the electron transport layer 284, and the electron injection layer 285. The light emitting and receiving device may also have other functional layers, such as a hole blocking layer or an electron blocking layer.

[0236] The light emitting and receiving device may have a layer that serves as both the light emitting layer and the active layer, instead of the active layer 273 and the light emitting layer 283R. For example, the layer that serves as both the light emitting layer and the active layer may be a layer containing three materials: an n-type semiconductor that can be used for the active layer 273, a p-type semiconductor that can be used for the active layer 273, and a light emitting material that can be used for the light emitting layer 283R.

[0237] It is preferable that the lowest energy absorption band in the absorption spectrum of the mixed material of n-type and p-type semiconductors does not overlap with the maximum peak in the emission spectrum (PL spectrum) of the luminescent substance, and it is more preferable that they are sufficiently separated from each other.

[0238] In a light receiving / emitting device, a conductive film that transmits visible light is used for the electrode on the light extraction side, and a conductive film that reflects visible light is preferably used for the electrode on the non-light extraction side.

[0239] The functions and materials of the layers constituting the light receiving and emitting device are similar to those of the light emitting device and the light receiving device, and therefore detailed description thereof will be omitted.

[0240] <Configuration Example 7 of Display Device> A configuration different from the display device 280G shown in FIGS. 6A and 6B is shown in FIGS. 6C and 6D.

[0241] A display device 280H shown in FIGS. 6C and 6D has a light-emitting layer 283R on the first electrode 281 side and an active layer 273 on the second electrode 275 side.

[0242] This embodiment mode can be combined with other embodiment modes as appropriate.

[0243] Embodiment 3 In this embodiment, details of a display device which is one embodiment of the present invention will be described.

[0244] A display device according to one embodiment of the present invention includes a light-receiving device and a light-emitting device in a display portion. The light-receiving device described in Embodiment 1 can be suitably used in the display device according to one embodiment of the present invention. The display device according to one embodiment of the present invention includes a light-receiving device and a light-emitting device in a display portion, has a function of displaying an image using the light-emitting device, and further has one or both of an imaging function and a sensing function.

[0245] Alternatively, a display device of one embodiment of the present invention includes a light-emitting and receiving device (also referred to as a light-emitting and receiving device) and a light-emitting device.

[0246] First, a display device having a light receiving device and a light emitting device will be described.

[0247] In a display device according to one embodiment of the present invention, a plurality of pixels are arranged in a matrix in a display portion. The pixels include a light-emitting device and a light-receiving device. That is, in a display device according to one embodiment of the present invention, light-emitting devices are arranged in a matrix in a display portion, and an image can be displayed on the display portion. Furthermore, light-receiving devices are arranged in a matrix in the display portion, and the display portion has one or both of an imaging function and a sensing function. The display portion can be used as an image sensor and / or a touch sensor. That is, by detecting light in the display portion, an image can be captured or a touch operation of an object (such as a finger or a pen) can be detected. Furthermore, in the display device according to one embodiment of the present invention, a light-emitting device can be used as a light source for a sensor. Therefore, a light-receiving portion and a light source are not required separately from the display device, and the number of components in an electronic device can be reduced.

[0248] 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). This makes it possible to capture an image or detect a touch operation even in a dark place.

[0249] A display device according to one embodiment of the present invention 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).

[0250] In one embodiment of the present invention, an organic EL element (also referred to as an organic EL device) is used as a light-emitting device, and an organic photodiode is used as a light-receiving device. The organic EL element 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 element.

[0251] A display device according to one embodiment of the present invention will be described below.

[0252] <Structure Example 1 of Display Device> Cross-sectional views of display devices of one embodiment of the present invention are shown in FIGS. 7A to 7D and 7F.

[0253] A display device 200A shown in FIG. 7A has, between a substrate 201 and a substrate 209, a layer 203 having a light-receiving device, a functional layer 205, and a layer 207 having a light-emitting device.

[0254] The display device 200A has a configuration in which red (R), green (G), and blue (B) light is emitted from a layer 207 having a light-emitting device.

[0255] The light receiving devices included in the layer 203 having the light receiving devices can detect light incident from outside the display device 200A.

[0256] A display device 200B shown in FIG. 7B has, between a substrate 201 and a substrate 209, a layer 204 having a light-receiving and light-emitting device, a functional layer 205, and a layer 207 having a light-emitting device.

[0257] The display device 200B has a structure in which green (G) light and blue (B) light are emitted from the layer 207 having a light-emitting device, and red (R) light is emitted from the layer 204 having a light-receiving and light-emitting device. Note that in the display device of one embodiment of the present invention, the color of light emitted from the layer 204 having a light-receiving and light-emitting device is not limited to red. Furthermore, the color of light emitted from the layer 207 having a light-emitting device is not limited to a combination of green and blue.

[0258] The light emitting and receiving devices included in the layer 204 having the light emitting and receiving devices can detect light incident from outside the display device 200B. The light emitting and receiving devices can detect, for example, one or both of green (G) light and blue (B) light.

[0259] The functional layer 205 has a circuit for driving the light-receiving device or the light-emitting and receiving device, and a circuit for driving the light-emitting device. The functional layer 205 may be provided with a switch, a transistor, a capacitor, a resistor, wiring, a terminal, etc. Note that when the light-emitting device and the light-receiving device are driven by a passive matrix method, a configuration without a switch or a transistor may be used.

[0260] The display device of one embodiment of the present invention may have a function of detecting an object, such as a finger, touching the display device (a function as a touch panel). For example, as shown in FIG. 7C , light emitted by a light-emitting device in the layer 207 having a light-emitting device is reflected by a finger 202 touching the display device 200A, and the light-receiving device in the layer 203 having a light-receiving device detects the reflected light. This makes it possible to detect that the finger 202 has touched the display device 200A. Furthermore, in the display device 200B, light emitted by a light-emitting device in the layer 207 having a light-emitting device is reflected by a finger touching the display device 200B, and the light-receiving device in the layer 204 having a light-receiving device can detect the reflected light. Note that, although a case where light emitted from a light-emitting device is reflected by an object will be described below as an example, light may also be scattered by the object.

[0261] As shown in FIG. 7D, the display device of one embodiment of the present invention may have a function of detecting or capturing an image of an object that is close to (not in contact with) the display device.

[0262] The display device of one embodiment of the present invention may have a function of detecting a fingerprint of a finger 202. Fig. 7E shows an image captured by the display device of one embodiment of the present invention. In Fig. 7E, the outline of the finger 202 is indicated by a dashed line within an imaging area 263, and the outline of the contact portion 261 is indicated by a dashed line. Within the contact portion 261, a high-contrast image of a fingerprint 262 can be captured depending on the difference in the amount of light incident on the light-receiving device (or the light-receiving and light-emitting device).

[0263] The display device of one embodiment of the present invention can also function as a pen tablet. Figure 7F shows a state in which the tip of a stylus 208 is slid in the direction of the dashed arrow while touching the substrate 209.

[0264] As shown in Figure 7F, the scattered light scattered between the tip of the stylus 208 and the contact surface of the substrate 209 is incident on a light receiving device (or light receiving and emitting device) located at the overlapping portion with the contact surface, thereby enabling the position of the tip of the stylus 208 to be detected with high accuracy.

[0265] 7G shows an example of a trajectory 266 of the stylus 208 detected by the display device of one embodiment of the present invention. The display device of one embodiment of the present invention can detect the position of a detectable object such as the stylus 208 with high positional accuracy, and therefore can perform high-resolution drawing in a drawing application or the like. Furthermore, unlike the case where a capacitive touch sensor or an electromagnetic induction touch pen is used, the display device can detect the position of even a highly insulating detectable object. Therefore, the material of the tip of the stylus 208 is not limited, and various writing implements (for example, a brush, a glass pen, a feather pen, and the like) can be used.

[0266] The pixel arrangement will be described.

[0267] A display device according to one embodiment of the present invention includes a plurality of pixels arranged in a matrix, each of which includes a plurality of sub-pixels, and each of which includes one light-emitting device, one light-receiving device, or one light-receiving device.

[0268] Each of the plurality of pixels has one or more of a subpixel having a light-emitting device, a subpixel having a light-receiving device, and a subpixel having a light-emitting and receiving device.

[0269] For example, a pixel may have multiple (eg, three or four) sub-pixels with light-emitting devices and one sub-pixel with a light-receiving device.

[0270] The light receiving device may be provided in all pixels or in some pixels. Also, one pixel may have multiple light receiving devices. Also, one light receiving device may be provided across multiple pixels. The resolution of the light receiving device and the resolution of the light emitting device may be different from each other.

[0271] When a pixel has three subpixels each having a light-emitting device, the three subpixels may be subpixels of three colors, R, G, and B, or subpixels of three colors, yellow (Y), cyan (C), and magenta (M), etc. When a pixel has four subpixels each having a light-emitting device, the four subpixels may be subpixels of four colors, R, G, B, and white (W), or subpixels of four colors, R, G, B, and Y, etc.

[0272] 7H, 7I, 7J, and 7K show examples of pixels having a plurality of subpixels each having a light-emitting device and one subpixel each having a light-receiving device. Note that the arrangement of the subpixels shown in this embodiment is not limited to the order shown in the drawings. For example, the positions of the subpixels (B) and (G) may be reversed.

[0273] Each of the pixels shown in Figures 7H, 7I, and 7J has a sub-pixel (PD) having a light-receiving function, a sub-pixel (R) that emits red light, a sub-pixel (G) that emits green light, and a sub-pixel (B) that emits blue light.

[0274] The pixel shown in Fig. 7H has a matrix arrangement, while the pixel shown in Fig. 7I has a stripe arrangement. Fig. 7J shows an example in which a subpixel (R) that emits red light, a subpixel (G) that emits green light, and a subpixel (B) that emits blue light are arranged in a single horizontal column, with a subpixel (PD) having a light-receiving function arranged below them. That is, in Fig. 7J, the subpixels (R), (G), and (B) are arranged in the same row, but in a different row from the subpixel (PD).

[0275] The pixel shown in Figure 7K has the same configuration as the pixel shown in Figure 7J, but also has a sub-pixel (X) that emits light other than R, G, and B. Examples of light other than R, G, and B include white (W), yellow (Y), cyan (C), magenta (M), and infrared light (IR). When the sub-pixel X emits infrared light, the sub-pixel (PD) having a light-receiving function preferably has a function to detect infrared light. The sub-pixel (PD) having a light-receiving function may have a function to detect both visible light and infrared light. The wavelength of light detected by the light-receiving device can be determined depending on the application of the sensor.

[0276] Alternatively, for example, a pixel may have a plurality of sub-pixels with light-emitting devices and one sub-pixel with a light-receiving device.

[0277] A display device having a light receiving and emitting device does not require changing the pixel arrangement to incorporate a light receiving function into the pixel, so it is possible to add one or both of an imaging function and a sensing function to the display section without reducing the aperture ratio and resolution.

[0278] The light emitting and receiving devices may be provided in all pixels or in some pixels, and one pixel may have a plurality of light emitting and receiving devices.

[0279] 8A to 8D show an example of a pixel having a plurality of sub-pixels each having a light-emitting device and one sub-pixel each having a light-receiving and light-emitting device.

[0280] 8A is a stripe array pixel having a subpixel (RPD) that emits red light and has a light-receiving function, a subpixel (G) that emits green light, and a subpixel (B) that emits blue light. In a display device in which a pixel is composed of three subpixels, R, G, and B, a light-emitting device used for the R subpixel can be replaced with a light-receiving / light-emitting device, thereby making it possible to fabricate a display device in which the pixel has a light-receiving function.

[0281] The pixel shown in Figure 8B has a subpixel (RPD) that emits red light and has a light-receiving function, a subpixel (G) that emits green light, and a subpixel (B) that emits blue light. The subpixel (RPD) is arranged in a column different from the subpixels (G) and (B). The subpixels (G) and (B) are arranged alternately in the same column, with one being arranged in an odd-numbered row and the other being arranged in an even-numbered row. Note that the subpixel arranged in a column different from the subpixels of other colors is not limited to red (R) and may be green (G) or blue (B).

[0282] 8C is arranged in a matrix and has a subpixel (RPD) that emits red light and has a light-receiving function, a subpixel (G) that emits green light, a subpixel (B) that emits blue light, and a subpixel (X) that emits light other than R, G, and B. Even in a display device in which a pixel is composed of four subpixels, R, G, B, and X, it is possible to manufacture a display device in which the pixel has a light-receiving function by replacing the light-emitting device used in the R subpixel with a light-receiving / light-emitting device.

[0283] FIG. 8D shows two pixels, each consisting of three subpixels surrounded by dotted lines. The pixel shown in FIG. 8D has a subpixel (RPD) that emits red light and has a light-receiving function, a subpixel (G) that emits green light, and a subpixel (B) that emits blue light. In the left pixel shown in FIG. 8D , the subpixel (G) is arranged in the same row as the subpixel (RPD), and the subpixel (B) is arranged in the same column as the subpixel (RPD). In the right pixel shown in FIG. 8D , the subpixel (G) is arranged in the same row as the subpixel (RPD), and the subpixel (B) is arranged in the same column as the subpixel (G). In the pixel layout shown in FIG. 8D , the subpixels (RPD), subpixels (G), and subpixels (B) are arranged repeatedly in both odd and even rows, and in each column, subpixels of different colors are arranged in the odd and even rows.

[0284] Fig. 8E shows four pixels in a Pentile arrangement, with two adjacent pixels having subpixels that emit two different colors of light. The shapes of the subpixels shown in Fig. 8E represent the top surface shapes of the light-emitting devices or light-receiving / light-emitting devices included in the subpixels. Fig. 8F shows a modified example of the pixel arrangement shown in Fig. 8E.

[0285] The upper left pixel and the lower right pixel shown in Fig. 8E have a subpixel (RPD) that emits red light and has a light-receiving function, and a subpixel (G) that emits green light. The lower left pixel and the upper right pixel shown in Fig. 8E have a subpixel (G) that emits green light and a subpixel (B) that emits blue light.

[0286] The upper left pixel and the lower right pixel shown in Fig. 8F have a sub-pixel (RPD) that emits red light and has a light-receiving function, and a sub-pixel (G) that emits green light. The lower left pixel and the upper right pixel shown in Fig. 8F have a sub-pixel (RPD) that emits red light and has a light-receiving function, and a sub-pixel (B) that emits blue light.

[0287] In Fig. 8E, each pixel is provided with a sub-pixel (G) that emits green light. On the other hand, in Fig. 8F, each pixel is provided with a sub-pixel (RPD) that emits red light and has a light-receiving function. Because each pixel is provided with a sub-pixel that has a light-receiving function, the configuration shown in Fig. 8F can capture images with higher resolution than the configuration shown in Fig. 8E. This can improve the accuracy of biometric authentication, for example.

[0288] The top surface shapes of the light-emitting device and the light-receiving / light-emitting device are not particularly limited and may be circular, elliptical, polygonal, polygonal with rounded corners, etc. Fig. 8E shows an example of a circular top surface shape of the light-emitting device of the subpixel (G), and Fig. 8F shows an example of a square top surface shape. The top surface shapes of the light-emitting device and the light-receiving / light-emitting device of each color may be different from each other, or may be the same for some or all of the colors.

[0289] The aperture ratios of the sub-pixels of each color may be different from one another, or may be the same for some or all of the colors. For example, the aperture ratio of the sub-pixel (G in FIG. 8E , sub-pixel (RPD) in FIG. 8F ) provided in each pixel may be smaller than the aperture ratios of the sub-pixels of other colors.

[0290] Fig. 8G is a modified example of the pixel array shown in Fig. 8F. Specifically, the configuration in Fig. 8G can be obtained by rotating the configuration in Fig. 8F by 45°. In Fig. 8F, one pixel is described as being composed of two sub-pixels, but as shown in Fig. 8G, one pixel can also be considered as being composed of four sub-pixels.

[0291] In FIG. 8G, one pixel is described as being composed of four subpixels surrounded by dotted lines. One pixel has two subpixels (RPD), one subpixel (G), and one subpixel (B). By having multiple subpixels with light-receiving functions in one pixel, imaging can be performed with high resolution. This improves the accuracy of biometric authentication. For example, the imaging resolution can be set to the root double of the display resolution.

[0292] A display device to which the configuration shown in Figure 8F or 8G is applied has p (p is an integer of 2 or more) first light-emitting devices, q (q is an integer of 2 or more) second light-emitting devices, and r (r is an integer greater than p and greater than q) light-receiving and light-emitting devices. p and r satisfy r = 2p. Furthermore, p, q, and r satisfy r = p + q. One of the first light-emitting devices and the second light-emitting devices emits green light, and the other emits blue light. The light-receiving and light-emitting device emits red light and has a light-receiving function.

[0293] For example, when detecting a touch operation using a light-emitting / receiving device, it is preferable that the light emitted from the light source is less visible to the user. Because blue light is less visible than green light, it is preferable that the light source be a light-emitting device that emits blue light. Therefore, it is preferable that the light-emitting / receiving device has a function of receiving blue light.

[0294] As described above, pixels with various arrangements can be applied to the display device of this embodiment mode.

[0295] A detailed structure of a display device according to one embodiment of the present invention will be described below with reference to FIGS.

[0296] <Configuration Example 2 of Display Device> [Configuration Example 2-1 of Display Device] A configuration example of a display device according to one embodiment of the present invention is shown in Fig. 9A. Fig. 9A is a cross-sectional view of a display device 100A.

[0297] The display device 100A includes a light receiving device 110 and a light emitting device 190 .

[0298] The light-emitting device 190 has a pixel electrode 191, a buffer layer 192, a light-emitting layer 193, a buffer layer 194, and a common electrode 115 stacked in this order. The buffer layer 192 can have one or both of a hole injection layer and a hole transport layer. The light-emitting layer 193 has an organic compound. The buffer layer 194 can have one or both of an electron injection layer and an electron transport layer. The light-emitting device 190 has a function of emitting visible light 121. Note that the display device 100A may further have a light-emitting device having a function of emitting infrared light.

[0299] The light-receiving device 110 has a pixel electrode 191, a buffer layer 182, an active layer 183, a buffer layer 184, and a common electrode 115 stacked in this order. The buffer layer 182 may have a hole transport layer. The active layer 183 includes an organic compound. The buffer layer 184 may have an electron transport layer. The light-receiving device 110 has a function of detecting visible light. The light-receiving device 110 may also have a function of detecting infrared light.

[0300] In the present embodiment, the pixel electrode 191 functions as an anode and the common electrode 115 functions as a cathode in both the light-emitting device 190 and the light-receiving device 110. In other words, by driving the light-receiving device 110 by applying a reverse bias between the pixel electrode 191 and the common electrode 115, the display device 100A can detect light incident on the light-receiving device 110, generate charges, and extract them as a current.

[0301] The pixel electrode 191, the buffer layer 182, the active layer 183, the light-emitting layer 193, the buffer layer 184, the buffer layer 194, and the common electrode 115 may each have a single layer structure or a laminated structure.

[0302] The pixel electrodes 191 are located on the insulating layer 214. Each pixel electrode 191 can be formed using the same material and in the same process. The ends of the pixel electrodes 191 are covered with a partition wall 216. Two adjacent pixel electrodes 191 are electrically insulated (or electrically separated) from each other by the partition wall 216.

[0303] The partition wall 216 is preferably an organic insulating film. 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 is a layer that transmits visible light. Instead of the partition wall 216, a partition wall that blocks visible light may be provided.

[0304] The common electrode 115 is a layer that is used in common by the light-receiving device 110 and the light-emitting device 190 .

[0305] The materials and film thicknesses of the pair of electrodes of the light-receiving device 110 and the light-emitting device 190 can be made the same, which leads to a reduction in manufacturing cost of the display device and a simplification of the manufacturing process.

[0306] The display device 100A includes a light receiving device 110, a light emitting device 190, a transistor 131, a transistor 132, and the like between a pair of substrates (substrate 151 and substrate 152).

[0307] In the light-receiving device 110, the buffer layer 182, active layer 183, and buffer layer 184, which are respectively located between the pixel electrode 191 and the common electrode 115, can also be referred to as organic layers (layers containing an organic compound). The pixel electrode 191 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 is configured to detect infrared light, the common electrode 115 has a function of transmitting infrared light. Furthermore, the pixel electrode 191 preferably has a function of reflecting infrared light.

[0308] The light receiving device 110 has a function of detecting light. Specifically, the light receiving device 110 is a photoelectric conversion element that receives light 122 incident from outside the display device 100A and converts the received light into an electrical signal. The light 122 can also be said to be light emitted by the light emitting device 190 and reflected by an object. The light 122 may also be incident on the light receiving device 110 via a lens or the like provided in the display device 100A.

[0309] In the light-emitting device 190, the buffer layer 192, the light-emitting layer 193, and the buffer layer 194, which are respectively located between the pixel electrode 191 and the common electrode 115, can be collectively referred to as an EL layer. The EL layer has at least the light-emitting layer 193. As described above, the pixel electrode 191 preferably has a function of reflecting visible light. Furthermore, the common electrode 115 has a function of transmitting visible light. Note that, when the display device 100A is configured to have a light-emitting device that emits infrared light, the common electrode 115 has a function of transmitting infrared light. Furthermore, the pixel electrode 191 preferably has a function of reflecting infrared light.

[0310] It is preferable that a micro-optical resonator (microcavity) structure is applied to the light-emitting device included in the display device of this embodiment.

[0311] The buffer layer 192 or the buffer layer 194 may function as an optical adjustment layer. By varying the thickness of the buffer layer 192 or the buffer layer 194, it is possible to enhance and extract light of a specific color in each light-emitting device.

[0312] The light-emitting device 190 has a function of emitting visible light. Specifically, the light-emitting device 190 is an electroluminescent device that emits light toward the substrate 152 by applying a voltage between the pixel electrode 191 and the common electrode 115 (see visible light 121).

[0313] The pixel electrode 191 of the light-receiving device 110 is electrically connected to the source or drain of the transistor 131 through an opening provided in the insulating layer 214 .

[0314] A pixel electrode 191 of the light-emitting device 190 is electrically connected to the source or drain of the transistor 132 through an opening provided in the insulating layer 214 .

[0315] The transistor 131 and the transistor 132 are in contact with each other on the same layer (substrate 151 in FIG. 9A).

[0316] 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 190. This allows the display device to be thinner and the manufacturing process to be simplified compared to when the two circuits are formed separately.

[0317] Preferably, the light-receiving device 110 and the light-emitting device 190 are each covered with a protective layer 116. In Fig. 9A, the protective layer 116 is provided on and in contact with the common electrode 115. By providing the protective layer 116, it is possible to prevent impurities such as water from entering the light-receiving device 110 and the light-emitting device 190, thereby improving the reliability of the light-receiving device 110 and the light-emitting device 190. In addition, the protective layer 116 and the substrate 152 are bonded together by an adhesive layer 142.

[0318] A light-shielding layer 158 is provided on the surface of the substrate 152 facing the substrate 151. The light-shielding layer 158 has openings at positions overlapping the light-emitting device 190 and the light-receiving device 110.

[0319] Here, the light-receiving device 110 detects light emitted by the light-emitting device 190 and reflected by an object. However, there is a case where the light emitted by the light-emitting device 190 is reflected within the display device 100A and enters the light-receiving device 110 without passing through the object. The light-shielding layer 158 can suppress the influence of such stray light. For example, if the light-shielding layer 158 is not provided, the light 123 emitted by the light-emitting device 190 may be reflected by the substrate 152, and the reflected light 124 may enter the light-receiving device 110. By providing the light-shielding layer 158, it is possible to prevent the reflected light 124 from entering the light-receiving device 110. This reduces noise and increases the sensitivity of a sensor using the light-receiving device 110.

[0320] 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, a black matrix may be formed 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.

[0321] 9B and 9C show cross-sectional views of a display device 100B. In the following description of the display device, description of the same configuration as the display device described above may be omitted.

[0322] The display device 100B includes a light-emitting device 190B, a light-emitting device 190G, and a light-receiving and light-emitting device 190RPD.

[0323] The light-emitting device 190B has a pixel electrode 191, a buffer layer 192B, a light-emitting layer 193B, a buffer layer 194B, and a common electrode 115 stacked in this order. The light-emitting device 190B has a function of emitting blue light 121B.

[0324] The light-emitting device 190G includes, stacked in this order, a pixel electrode 191, a buffer layer 192G, a light-emitting layer 193G, a buffer layer 194G, and a common electrode 115. The light-emitting device 190G has a function of emitting green light 121G.

[0325] The light emitting and receiving device 190RPD has, stacked in this order, a pixel electrode 191, a buffer layer 192R, an active layer 183, a light emitting layer 193R, a buffer layer 194R, and a common electrode 115. The light emitting and receiving device 190RPD has a function of emitting red light 121R and a function of detecting light 122.

[0326] 9B shows a case where the light emitting and receiving device 190RPD functions as a light emitting device, in which the light emitting device 190B emits blue light, the light emitting device 190G emits green light, and the light emitting and receiving device 190RPD emits red light.

[0327] 9C shows a case where the light emitting and receiving device 190RPD functions as a light receiving device, in which the light emitting and receiving device 190RPD detects blue light emitted by the light emitting device 190B and green light emitted by the light emitting device 190G.

[0328] The display device 100B includes a light emitting and receiving device 190RPD, a light emitting device 190G, a light emitting device 190B, a transistor 132, and the like between a pair of substrates (substrate 151 and substrate 152).

[0329] The pixel electrode 191 is located on the insulating layer 214. Two adjacent pixel electrodes 191 are electrically insulated from each other by a partition wall 216. The pixel electrode 191 is electrically connected to the source or drain of the transistor 132 through an opening provided in the insulating layer 214.

[0330] The light emitting and receiving device and the light emitting device are preferably covered with a protective layer 116. The protective layer 116 and the substrate 152 are bonded together by an adhesive layer 142. A light blocking layer 158 is provided on the surface of the substrate 152 facing the substrate 151.

[0331] [Configuration Example 2-3 of Display Device] FIG. 10A shows a cross-sectional view of a display device 100C.

[0332] The display device 100C includes a light receiving device 110 and a light emitting device 190 .

[0333] The light-emitting device 190 has a pixel electrode 191, a common layer 112, a light-emitting layer 193, a common layer 114, and a common electrode 115, in this order. The common layer 112 can have one or both of a hole injection layer and a hole transport layer. The light-emitting layer 193 contains an organic compound. The common layer 114 can have one or both of an electron injection layer and an electron transport layer. The light-emitting device 190 has a function of emitting visible light. Note that the display device 100C may further have a light-emitting device having a function of emitting infrared light.

[0334] The light-receiving device 110 has a pixel electrode 191, a common layer 112, an active layer 183, a common layer 114, and a common electrode 115 stacked in this order. The active layer 183 contains an organic compound. The light-receiving device 110 has a function of detecting visible light. The light-receiving device 110 may also have a function of detecting infrared light.

[0335] The pixel electrode 191, the common layer 112, the active layer 183, the light-emitting layer 193, the common layer 114, and the common electrode 115 may each have a single-layer structure or a multilayer structure.

[0336] The pixel electrode 191 is located on the insulating layer 214. Two adjacent pixel electrodes 191 are electrically insulated from each other by a partition wall 216. The pixel electrode 191 is electrically connected to the source or drain of the transistor 132 through an opening provided in the insulating layer 214.

[0337] The common layer 112, the common layer 114, and the common electrode 115 are layers that are used in common for the light-receiving device 110 and the light-emitting device 190. By making at least some of the layers that constitute the light-receiving device 110 and the light-emitting device 190 have a common configuration, the manufacturing process of the display device can be reduced, which is preferable.

[0338] The display device 100C includes a light receiving device 110, a light emitting device 190, a transistor 131, a transistor 132, and the like between a pair of substrates (substrate 151 and substrate 152).

[0339] The light receiving device 110 and the light emitting device 190 are preferably each covered with a protective layer 116. The protective layer 116 and the substrate 152 are bonded together by an adhesive layer 142.

[0340] A resin layer 159 is provided on the surface of the substrate 152 facing the substrate 151. The resin layer 159 is provided at a position overlapping the light-emitting device 190, but is not provided at a position overlapping the light-receiving device 110.

[0341] 10B, the resin layer 159 can be configured to be provided in a position overlapping the light-emitting device 190 and to have an opening 159p in a position overlapping the light-receiving device 110. Alternatively, the resin layer 159 can be configured to be provided in an island shape in a position overlapping the light-emitting device 190 and not in a position overlapping the light-receiving device 110, as shown in FIG.

[0342] A light-shielding layer 158 is provided on the surface of the substrate 152 facing the substrate 151 and on the surface of the resin layer 159 facing the substrate 151. The light-shielding layer 158 has openings at positions overlapping the light-emitting device 190 and the light-receiving device 110.

[0343] Here, the light-receiving device 110 detects light emitted by the light-emitting device 190 and reflected by an object. However, there are cases where the light emitted by the light-emitting device 190 is reflected within the display device 100C and enters the light-receiving device 110 without passing through the object. The light-shielding layer 158 absorbs such stray light and can reduce the stray light incident on the light-receiving device 110. For example, the light-shielding layer 158 can absorb stray light 123a that passes through the resin layer 159 and is reflected by the surface of the substrate 152 facing the substrate 151. The light-shielding layer 158 can also absorb stray light 123b before it reaches the resin layer 159. This can reduce the stray light incident on the light-receiving device 110. This can reduce noise and increase the sensitivity of a sensor using the light-receiving device 110. In particular, it is preferable for the light-shielding layer 158 to be located close to the light-emitting device 190, as this can further reduce stray light. Furthermore, if the light-shielding layer 158 is located close to the light-emitting device 190, the viewing angle dependency of the display can be suppressed, which is also preferable from the viewpoint of improving the display quality.

[0344] The light-detecting range of the light-receiving device 110 can be controlled by providing the light-shielding layer 158. When the light-shielding layer 158 is positioned away from the light-receiving device 110, the imaging range is narrowed, and the imaging resolution can be increased.

[0345] When the resin layer 159 has an opening, the light-shielding layer 158 preferably covers at least a part of the opening and at least a part of the side surface of the resin layer 159 exposed at the opening.

[0346] When the resin layer 159 is provided in an island shape, the light-shielding layer 158 preferably covers at least a part of the side surface of the resin layer 159 .

[0347] In this way, since the light-shielding layer 158 is provided along the shape of the resin layer 159, the distance from the light-shielding layer 158 to the light-emitting device 190 (specifically, the light-emitting region of the light-emitting device 190) is shorter than the distance from the light-shielding layer 158 to the light-receiving device 110 (specifically, the light-receiving region of the light-receiving device 110). This makes it possible to reduce sensor noise, increase imaging resolution, and suppress viewing angle dependency of the display. Therefore, it is possible to improve both the display quality and imaging quality of the display device.

[0348] The resin layer 159 is a layer that transmits light emitted from the light-emitting device 190. Examples of materials for the resin layer 159 include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, and precursors of these resins. The structure provided between the substrate 152 and the light-shielding layer 158 is not limited to a resin layer, and an inorganic insulating film or the like may also be used. The thicker the structure, the greater the difference between the distance from the light-shielding layer to the light-receiving device and the distance from the light-shielding layer to the light-emitting device. Organic insulating films such as resins are easy to form thick, so they are suitable for the structure.

[0349] To compare the distance from the light-shielding layer 158 to the light-receiving device 110 with the distance from the light-shielding layer 158 to the light-emitting device 190, for example, the shortest distance L1 from the end of the light-shielding layer 158 on the light-receiving device 110 side to the common electrode 115 and the shortest distance L2 from the end of the light-shielding layer 158 on the light-emitting device 190 side to the common electrode 115 can be used. Since the shortest distance L2 is shorter than the shortest distance L1, stray light from the light-emitting device 190 can be suppressed and the sensitivity of the sensor using the light-receiving device 110 can be increased. Furthermore, the viewing angle dependency of the display can be suppressed. Since the shortest distance L1 is longer than the shortest distance L2, the imaging range of the light-receiving device 110 can be narrowed and the imaging resolution can be increased.

[0350] By configuring the adhesive layer 142 so that the portion that overlaps the light-receiving device 110 is thicker than the portion that overlaps the light-emitting device 190, a difference can be created between the distance from the light-shielding layer 158 to the light-receiving device 110 and the distance from the light-shielding layer 158 to the light-emitting device 190.

[0351] Below, a more detailed structure of the display device of one embodiment of the present invention will be described with reference to FIGS.

[0352] [Configuration Example 2-4 of Display Device] FIG. 11 shows a perspective view of a display device 100D, and FIG. 12 shows a cross-sectional view of the display device 100D.

[0353] The display device 100D has a configuration in which a substrate 152 and a substrate 151 are bonded together. In Fig. 11, the substrate 152 is clearly indicated by a dashed line.

[0354] The display device 100D includes a display portion 162, a circuit 164, wiring 165, and the like. Fig. 11 shows an example in which an IC (integrated circuit) 173 and an FPC 172 are mounted on the display device 100D. Therefore, the configuration shown in Fig. 11 can also be considered as a display module including the display device 100D, the IC, and the FPC.

[0355] The circuit 164 can be, for example, a scanning line driver circuit.

[0356] The wiring 165 has a function of supplying signals and power to the display portion 162 and the circuit 164. The signals and power are input to the wiring 165 from the outside via the FPC 172 or from the IC 173.

[0357] 11 shows an example in which an IC 173 is provided on a substrate 151 by a chip-on-glass (COG) method, a chip-on-film (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 100D and the display module may not necessarily include an IC. Alternatively, the IC may be mounted on an FPC by a COF method or the like.

[0358] Figure 12 shows an example of a cross section of the display device 100D shown in Figure 11, with a portion of the area including the FPC 172, a portion of the area including the circuit 164, a portion of the area including the display unit 162, and a portion of the area including the end portion cut away.

[0359] A display device 100D shown in FIG. 12 includes a transistor 241, a transistor 245, a transistor 246, a transistor 247, a light-emitting device 190B, a light-emitting device 190G, a light-receiving and light-emitting device 190RPD, and the like between a substrate 151 and a substrate 152.

[0360] The substrate 152 and the protective layer 116 are bonded together by an adhesive layer 142. A solid sealing structure, a hollow sealing structure, or the like can be applied to seal the light-emitting device 190B, the light-emitting device 190G, and the light-receiving and light-emitting device 190RPD. In Fig. 12, the space surrounded by the substrate 152, the adhesive layer 142, and the insulating layer 214 is sealed by the adhesive layer 142, and a solid sealing structure is applied.

[0361] The light-emitting device 190B has a layered structure in which a pixel electrode 191, a common layer 112, a light-emitting layer 193B, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214 side. The pixel electrode 191 is connected to a conductive layer 222b of a transistor 247 through an opening provided in the insulating layer 214. The transistor 247 has a function of controlling driving of the light-emitting device 190B. An end of the pixel electrode 191 is covered with a partition wall 216. The pixel electrode 191 contains a material that reflects visible light, and the common electrode 115 contains a material that transmits visible light.

[0362] The light-emitting device 190G has a layered structure in which a pixel electrode 191, a common layer 112, a light-emitting layer 193G, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214 side. The pixel electrode 191 is connected to a conductive layer 222b of a transistor 246 through an opening provided in the insulating layer 214. The transistor 246 has a function of controlling driving of the light-emitting device 190G.

[0363] The light emitting and receiving device 190RPD has a layered structure in which a pixel electrode 191, a common layer 112, an active layer 183, a light emitting layer 193R, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214 side. The pixel electrode 191 is electrically connected to a conductive layer 222b of a transistor 245 through an opening provided in the insulating layer 214. The transistor 245 has a function of controlling driving of the light emitting and receiving device 190RPD.

[0364] Light emitted from the light-emitting device 190B, the light-emitting device 190G, and the light-receiving and light-emitting device 190RPD is emitted toward the substrate 152. Furthermore, light is incident on the light-receiving and light-emitting device 190RPD via the substrate 152 and the adhesive layer 142. It is preferable to use a material that is highly transparent to visible light for the substrate 152 and the adhesive layer 142.

[0365] The pixel electrodes 191 of the light-emitting device 190B, the light-emitting device 190G, and the light-receiving and light-emitting device 190RPD 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 commonly used in the light-emitting device 190B, the light-emitting device 190G, and the light-receiving and light-emitting device 190RPD. The light-receiving and light-emitting device 190RPD has a configuration in which an active layer 183 is added to the configuration of a light-emitting device that emits red light. Furthermore, the light-emitting device 190B, the light-emitting device 190G, and the light-receiving and light-emitting device 190RPD can have a common configuration except for the configurations of the active layer 183 and the light-emitting layers 193 of each color. This allows a light-receiving function to be added to the display unit 162 of the display device 100D without significantly increasing the number of manufacturing processes.

[0366] A light-shielding layer 158 is provided on the surface of the substrate 152 facing the substrate 151. The light-shielding layer 158 has openings at positions overlapping the light-emitting device 190B, the light-emitting device 190G, and the light-receiving device 190RPD. By providing the light-shielding layer 158, the range in which the light-emitting and light-receiving device 190RPD detects light can be controlled. As described above, it is preferable to control the light incident on the light-receiving and light-emitting device by adjusting the position of the opening in the light-shielding layer provided at a position overlapping the light-receiving and light-emitting device 190RPD. Furthermore, by providing the light-shielding layer 158, it is possible to prevent light from being directly incident on the light-emitting and light-receiving device 190RPD from the light-emitting device 190 without passing through an object. Therefore, a sensor with low noise and high sensitivity can be realized.

[0367] The transistor 241, the transistor 245, the transistor 246, and the transistor 247 are all formed over a substrate 151. These transistors can be manufactured using the same material and through the same process.

[0368] 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.

[0369] It is preferable that at least one insulating layer covering the transistor is made of a material that is difficult for impurities such as water or hydrogen to diffuse into. 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.

[0370] The insulating layer 211, the insulating layer 213, and the insulating layer 215 are preferably formed using an inorganic insulating film. Examples of inorganic insulating films that can be used include a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, and an aluminum nitride film. Alternatively, a hafnium oxide film, a hafnium oxynitride film, a hafnium nitride oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, and a neodymium oxide film may be used. Two or more of the above insulating films may be stacked. A base film may be provided between the substrate 151 and the transistor. The above inorganic insulating film may also be used for the base film.

[0371] 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 100D. This can prevent impurities from entering from the edge of the display device 100D through 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 100D, so that the organic insulating film is not exposed at the edge of the display device 100D.

[0372] 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.

[0373] By providing a protective layer 116 that covers the light-emitting device 190B, the light-emitting device 190G, and the light-receiving and light-emitting device 190RPD, it is possible to prevent impurities such as water from entering the light-emitting device 190B, the light-emitting device 190G, and the light-receiving and light-emitting device 190RPD, thereby improving the reliability of the light-emitting device 190B, the light-emitting device 190G, and the light-receiving and light-emitting device 190RPD.

[0374] 12 , 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 100D.

[0375] In a region 228 near the edge of the display device 100D, 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 100D.

[0376] The protective layer 116 may have a single layer or a laminated structure. For example, the protective layer 116 may have a laminated structure of an organic insulating film and an inorganic insulating film. In this case, it is preferable that the end of the inorganic insulating film extends further outward than the end of the organic insulating film.

[0377] The transistors 241, 245, 246, and 247 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.

[0378] 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.

[0379] The transistors 241, 245, 246, and 247 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.

[0380] The crystallinity of a semiconductor material used for a transistor is not particularly limited, and any of an amorphous semiconductor and a crystalline semiconductor (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0381] The semiconductor layer of the transistor preferably contains a metal oxide (also referred to as an oxide semiconductor). Alternatively, the semiconductor layer of the transistor may contain silicon. Examples of silicon include amorphous silicon and crystalline silicon (such as low-temperature polysilicon and single-crystal silicon).

[0382] 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.

[0383] 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.

[0384] When the semiconductor layer is an In-M-Zn oxide, the atomic ratio of In in the In-M-Zn oxide is preferably equal to or greater than the atomic ratio of M. Examples of atomic ratios of metal elements in such In-M-Zn oxides include a composition in which In:M:Zn=1:1:1 or thereabouts, a composition in which In:M:Zn=1:1:1.2 or thereabouts, a composition in which In:M:Zn=2:1:3 or thereabouts, a composition in which In:M:Zn=3:1:2 or thereabouts, a composition in which In:M:Zn=4:2:3 or thereabouts, a composition in which In:M:Zn=4:2:4.1 or thereabouts, a composition in which In:M:Zn=5:1:3 or thereabouts, a composition in which In:M:Zn=5:1:6 or thereabouts, a composition in which In:M:Zn=5:1:7 or thereabouts, a composition in which In:M:Zn=5:1:8 or thereabouts, a composition in which In:M:Zn=6:1:6 or thereabouts, and a composition in which In:M:Zn=5:2:5 or thereabouts. The term "nearby composition" includes a range of ±30% of the desired atomic ratio.

[0385] 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 the atomic ratio of In is 4, the atomic ratio of Ga is 1 or more and 3 or less, and the atomic ratio of Zn is 2 or more and 4 or less. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn=5:1:6 or thereabout, this includes a case where, when the atomic ratio of In is 5, the atomic ratio of Ga is more than 0.1 and 2 or less, and the atomic ratio of Zn is 5 or more and 7 or less. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn=1:1:1 or thereabout, this includes a case where, when the atomic ratio of In is 1, the atomic ratio of Ga is more than 0.1 and 2 or less, and the atomic ratio of Zn is more than 0.1 and 2 or less.

[0386] 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.

[0387] A connection portion 244 is provided in a region of the substrate 151 where the substrate 152 does not overlap. In the connection portion 244, 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 191, is exposed on the upper surface of the connection portion 244. This allows the connection portion 244 and the FPC 172 to be electrically connected via the connection layer 242.

[0388] 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.

[0389] The substrate 151 and the substrate 152 can be formed using glass, quartz, ceramic, sapphire, resin, etc. When the substrate 151 and the substrate 152 are formed using a flexible material, the flexibility of the display device can be increased.

[0390] The adhesive layer can be made of various curable adhesives, such as photo-curable adhesives (e.g., ultraviolet curable), reactive curable adhesives, thermosetting adhesives, and anaerobic adhesives. Examples of such adhesives include epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, and EVA (ethylene vinyl acetate) resin. Materials with low moisture permeability, such as epoxy resin, are particularly preferred. Two-component resins may also be used. Adhesive sheets, etc., may also be used.

[0391] The connection layer may be made of an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0392] The above descriptions can be referred to for the configurations and materials of the light emitting devices 190G and 190B and the light receiving and emitting device 190RPD.

[0393] 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.

[0394] Examples of light-transmitting conductive materials include conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, and zinc oxide containing gallium, or graphene. Alternatively, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, and titanium, or alloy materials containing such metal materials, can be used. Alternatively, nitrides of such metal materials (e.g., titanium nitride) can be used. When using metal materials or alloy materials (or their nitrides), it is preferable to thin them sufficiently to ensure light-transmitting properties. Furthermore, stacked films of the above materials can be used as conductive layers. For example, stacked films of an alloy of silver and magnesium and indium tin oxide are preferable because they can enhance conductivity. These materials can also be used as conductive layers, such as various wirings and electrodes constituting display devices, and conductive layers (conductive layers functioning as pixel electrodes or common electrodes) in light-emitting devices and light-receiving devices (or light-receiving and light-emitting devices).

[0395] 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.

[0396] [Configuration Example 2-5 of Display Device] FIGS. 13 and 14A show cross-sectional views of a display device 100E. The perspective view of the display device 100E is similar to that of the display device 100D (FIG. 6). FIG. 13 shows an example of a cross-section of the display device 100E 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. 14A shows an example of a cross-section of the display device 100E when a portion of the display unit 162 is cut away. FIG. 13 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. 14A 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.

[0397] The display device 100E shown in Figures 13 and 14A has a transistor 243, a transistor 248, a transistor 249, a transistor 240, a light-emitting device 190R, a light-emitting device 190G, a light-emitting device 190B, a light-receiving device 110, etc. between a substrate 153 and a substrate 154.

[0398] The resin layer 159 and the common electrode 115 are bonded via an adhesive layer 142, and a solid sealing structure is applied to the display device 100E.

[0399] 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.

[0400] The display device 100E 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, a resin layer 159, a light-shielding layer 158, 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 100E.

[0401] 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.

[0402] The light-emitting device 190R has a layered structure in which a pixel electrode 191, a common layer 112, a light-emitting layer 193R, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214b side. The pixel electrode 191 is connected to a conductive layer 169 through an opening provided in the insulating layer 214b. The conductive layer 169 is connected to a conductive layer 222b of the transistor 248 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 191 is electrically connected to the transistor 248. The transistor 248 has a function of controlling the driving of the light-emitting device 190R.

[0403] Similarly, the light-emitting device 190G has a layered structure in which a pixel electrode 191, a common layer 112, a light-emitting layer 193G, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214b side. The pixel electrode 191 is electrically connected to a low-resistance region 231n of the transistor 249 via the conductive layer 169 and the conductive layer 222b of the transistor 249. In other words, the pixel electrode 191 is electrically connected to the transistor 249. The transistor 249 has a function of controlling the driving of the light-emitting device 190G.

[0404] The light-emitting device 190B has a layered structure in which the pixel electrode 191, the common layer 112, the light-emitting layer 193B, the common layer 114, and the common electrode 115 are layered in this order from the insulating layer 214b side. The pixel electrode 191 is electrically connected to the low-resistance region 231n of the transistor 240 via the conductive layer 169 and the conductive layer 222b of the transistor 240. In other words, the pixel electrode 191 is electrically connected to the transistor 240. The transistor 240 has a function of controlling the driving of the light-emitting device 190B.

[0405] The light receiving device 110 has a layered structure in which a pixel electrode 191, a common layer 112, an active layer 183, a common layer 114, and a common electrode 115 are layered in this order from the insulating layer 214b side.

[0406] The edge of the pixel electrode 191 is covered with a partition wall 216. The pixel electrode 191 includes a material that reflects visible light, and the common electrode 115 includes a material that transmits visible light.

[0407] 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.

[0408] Each pixel electrode 191 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 configurations of the active layer 183 and the light-emitting layer. This allows the light-receiving device 110 to be built into the display device 100E without significantly increasing the number of manufacturing processes.

[0409] A resin layer 159 and a light-shielding layer 158 are provided on the surface of the insulating layer 157 facing the substrate 153. The resin layer 159 is provided at a position overlapping the light-emitting devices 190R, 190G, and 190B, but not at a position overlapping the light-receiving device 110. The light-shielding layer 158 is provided to cover the surface of the insulating layer 157 facing the substrate 153, the side surface of the resin layer 159, and the surface of the resin layer 159 facing the substrate 153. The light-shielding layer 158 has openings at a position overlapping the light-receiving device 110 and at positions overlapping each of the light-emitting devices 190R, 190G, and 190B. The provision of the light-shielding layer 158 allows the range in which the light-receiving device 110 detects light to be controlled. Furthermore, the provision of the light-shielding layer 158 prevents light from the light-emitting devices 190R, 190G, and 190B from directly entering the light-receiving device 110 without passing through an object. Therefore, a sensor with low noise and high sensitivity can be realized. By providing the resin layer 159, the distance from the light-shielding layer 158 to the light-emitting device of each color is shorter than the distance from the light-shielding layer 158 to the light-receiving device 110. This makes it possible to reduce sensor noise while suppressing the viewing angle dependency of the display. Therefore, it is possible to improve both display quality and imaging quality.

[0410] 13 , the partition wall 216 has an opening between the light-receiving device 110 and the light-emitting device 190R. A light-shielding layer 219a is provided to fill the opening. The light-shielding layer 219a is located between the light-receiving device 110 and the light-emitting device 190R. The light-shielding layer 219a absorbs light emitted by the light-emitting device 190R. This makes it possible to suppress stray light entering the light-receiving device 110.

[0411] The spacers 219b are provided on the partition walls 216 and are positioned between the light-emitting devices 190G and 190B. The top surfaces of the spacers 219b are preferably closer to the light-shielding layer 158 than the top surface of the light-shielding layer 219a. For example, the sum of the height (thickness) of the partition walls 216 and the height (thickness) of the spacers 219b is preferably greater than the height (thickness) of the light-shielding layer 219a. This makes it easier to fill the adhesive layer 142. As shown in FIG. 14A , the light-shielding layer 158 may be in contact with the common electrode 115 (or a protective layer) in the overlapping portion between the spacers 219b and the light-shielding layer 158.

[0412] A connection portion 244 is provided in a region of the substrate 153 where the substrate 154 does not overlap. In the connection portion 244, 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 169. On the top surface of the connection portion 244, the conductive layer 166 obtained by processing the same conductive film as the pixel electrode 191 is exposed. This allows the connection portion 244 and the FPC 172 to be electrically connected via the connection layer 242.

[0413] The transistor 243, the transistor 248, the transistor 249, and the transistor 240 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.

[0414] 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.

[0415] 13 and 14A , 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 FIGS. 13 and 14A . In FIGS. 13 and 14A , 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, an insulating layer covering the transistor may be provided.

[0416] 14B shows an example in which the top surface and side surfaces of the semiconductor layer are covered with an insulating layer 225. 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.

[0417] As described above, in the display device of one embodiment of the present invention, the difference in distance between the two light-emitting devices and the light-receiving device (or the light-receiving / light-emitting device) and the difference in distance between the two light-emitting devices and the opening in the light-blocking layer that overlaps with the light-receiving device (or the light-receiving / light-emitting device) are different from each other. With this configuration, the light-receiving device or the light-receiving / light-emitting device can receive more light from one of the two light-emitting devices than from the other. Therefore, for example, in the display device of one embodiment of the present invention, more light from the light-emitting device used as a light source can be incident on the light-receiving device or the light-receiving / light-emitting device.

[0418] <Example of Pixel Circuit> 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 in a display portion. The first pixel circuit and the second pixel circuit are arranged in a matrix.

[0419] FIG. 15A shows an example of a first pixel circuit having a light-receiving device, and FIG. 15B shows an example of a second pixel circuit having a light-emitting device.

[0420] 15A 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.

[0421] 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.

[0422] 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.

[0423] 15B includes a light-emitting device EL, a transistor M5, a transistor M6, a transistor 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 element as the light-emitting device EL.

[0424] 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.

[0425] 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.

[0426] The wiring V1 to which the cathode of the light receiving device PD is electrically connected and the wiring V5 to which the cathode of the light emitting device EL is electrically connected can be in the same layer and at the same potential.

[0427] In the display device of one embodiment of the present invention, it is preferable that all of the transistors included in the pixel circuits PIX1 and PIX2 be transistors including a metal oxide (also referred to as an oxide semiconductor) in a semiconductor layer in which a channel is formed (hereinafter also referred to as an OS transistor). The OS transistor has an extremely small 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 the display device.

[0428] Alternatively, in the display device of one embodiment of the present invention, it is preferable to use, as all of the transistors included in the pixel circuits PIX1 and PIX2, transistors having silicon in a semiconductor layer where a channel is formed (hereinafter also referred to as Si transistors). Examples of silicon include single crystal silicon, polycrystalline silicon, amorphous silicon, and the like. In particular, it is preferable to use a transistor having low temperature polysilicon (LTPS) in a semiconductor layer (hereinafter also referred to as LTPS transistor). LTPS transistors have high field-effect mobility and can operate at high speed.

[0429] Furthermore, by using Si transistors such as LTPS transistors, it becomes easier to integrate various circuits consisting of CMOS circuits on the same substrate as the display unit, which simplifies the external circuits mounted on the display device and reduces component and mounting costs.

[0430] Alternatively, in the display device of one embodiment of the present invention, the pixel circuit PIX1 preferably includes two types of transistors. Specifically, the pixel circuit PIX1 preferably includes an OS transistor and an LTPS transistor. By changing the material of the semiconductor layer depending on the function required of the transistor, the quality of the pixel circuit PIX1 can be improved and the accuracy of sensing and imaging can be increased. In this case, the pixel circuit PIX2 may include either an OS transistor or an LTPS transistor, or both.

[0431] Furthermore, even when two types of transistors (for example, an OS transistor and an LTPS transistor) are used in a pixel, the use of the LTPS transistor makes it easy to fabricate various circuits configured with CMOS circuits on the same substrate as the display unit, thereby simplifying the external circuits mounted on the display device and reducing component and mounting costs.

[0432] 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, the small off-state current allows charge stored in a capacitor connected in series with the transistor to be held for a long period of time. Therefore, it is preferable to use OS transistors for the transistors M1, M2, and M5, which are connected in series with the capacitor C1 or C2.

[0433] It is preferable to use a Si transistor for the transistor M3, which allows the image data to be read out at high speed.

[0434] A display device having a display unit including a first pixel circuit having a light-receiving device and a second pixel circuit having a light-emitting device can be driven in any of an image display mode, an imaging mode, and a simultaneous image display and imaging mode. In the image display mode, for example, a full-color image can be displayed using the light-emitting device. In the imaging mode, for example, an image to be captured (e.g., a single color, such as green or blue) can be displayed using the light-emitting device, and the image can be captured using the light-receiving device. In the imaging mode, for example, fingerprint authentication can be performed. In the simultaneous image display and imaging mode, for example, some pixels can display an image to be captured using the light-emitting device and capture the image using the light-receiving device, and the remaining pixels can display a full-color image using the light-emitting device.

[0435] 15A and 15B, the transistors are shown as n-channel transistors, but p-channel transistors can also be used. The transistors are not limited to single-gate transistors and may further have a back gate.

[0436] It is 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-resolution display unit.

[0437] This embodiment mode can be combined with other embodiment modes as appropriate.

[0438] Embodiment 4 In this embodiment, a metal oxide (also referred to as an oxide semiconductor) that can be used for the OS transistor described in the above embodiment will be described.

[0439] The metal oxide preferably contains at least indium or zinc. It is particularly preferable that it contains indium and zinc. It is also preferable that it contains aluminum, gallium, yttrium, tin, or the like in addition to these. It may also contain one or more elements selected from boron, silicon, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, cobalt, and the like.

[0440] The metal oxide can be formed by a sputtering method, a chemical vapor deposition (CVD) method such as a metal organic chemical vapor deposition (MOCVD) method, or an atomic layer deposition (ALD) method.

[0441] <Classification of Crystal Structure> Examples of the crystal structure of an oxide semiconductor include amorphous (including completely amorphous), c-axis-aligned crystalline line (CAAC), nanocrystalline line (nc), cloud-aligned composite (CAC), single crystal, and polycrystalline.

[0442] The crystalline structure of the film or substrate can be evaluated using an X-ray diffraction (XRD) spectrum. For example, it can be evaluated using an XRD spectrum obtained by a GIXD (Grazing-Incident XRD) measurement. The GIXD method is also called the thin film method or the Seemann-Bohlin method.

[0443] For example, in the case of a quartz glass substrate, the shape of the peak in the XRD spectrum is almost symmetrical. On the other hand, in the case of an IGZO film having a crystalline structure, the shape of the peak in the XRD spectrum is asymmetrical. The asymmetrical shape of the peak in the XRD spectrum clearly indicates the presence of crystals in the film or substrate. In other words, if the shape of the peak in the XRD spectrum is not symmetrical, the film or substrate cannot be said to be in an amorphous state.

[0444] The crystalline structure of the film or substrate can be evaluated by a diffraction pattern (also referred to as a nanobeam electron diffraction pattern) observed by nanobeam electron diffraction (NBED). For example, a halo is observed in the diffraction pattern of a quartz glass substrate, and it can be confirmed that the quartz glass is in an amorphous state. Furthermore, a spot-like pattern is observed in the diffraction pattern of an IGZO film formed at room temperature, rather than a halo. For this reason, it is estimated that the IGZO film formed at room temperature is neither crystalline nor amorphous, but is in an intermediate state, and it cannot be concluded that it is in an amorphous state.

[0445] <Structure of Oxide Semiconductor> Note that oxide semiconductors may be classified differently from the above when focusing on their structure. For example, oxide semiconductors are classified into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors. Examples of non-single-crystal oxide semiconductors include the above-mentioned CAAC-OS and nc-OS. Non-single-crystal oxide semiconductors include polycrystalline oxide semiconductors, pseudo-amorphous-like oxide semiconductors (a-like OSs), amorphous oxide semiconductors, and the like.

[0446] Here, the above-mentioned CAAC-OS, nc-OS, and a-like OS will be described in detail.

[0447] [CAAC-OS] A CAAC-OS is an oxide semiconductor having multiple crystalline regions, each with its c-axis aligned in a specific direction. The specific direction refers to the thickness direction of the CAAC-OS film, the normal direction to the surface where the CAAC-OS film is formed, or the normal direction to the surface of the CAAC-OS film. A crystalline region is a region having periodic atomic arrangement. If the atomic arrangement is considered as a lattice arrangement, a crystalline region is also a region with a uniform lattice arrangement. Furthermore, a CAAC-OS has a region where multiple crystalline regions are connected in the a-b plane direction, and the region may have distortion. Note that distortion refers to a portion where the lattice arrangement changes between a region with a uniform lattice arrangement and a region with another uniform lattice arrangement in a region where multiple crystalline regions are connected. In other words, a CAAC-OS is an oxide semiconductor whose c-axes are aligned and whose orientation is not clearly aligned in the a-b plane direction.

[0448] Each of the multiple crystalline regions is composed of one or more minute crystals (crystals with a maximum diameter of less than 10 nm). When a crystalline region is composed of a single minute crystal, the maximum diameter of the crystalline region is less than 10 nm. When a crystalline region is composed of many minute crystals, the size of the crystalline region may be several tens of nanometers.

[0449] In an In-M-Zn oxide (wherein the element M is one or more elements selected from aluminum, gallium, yttrium, tin, titanium, and the like), the CAAC-OS tends to have a layered crystal structure (also referred to as a layered structure) in which a layer containing indium (In) and oxygen (hereinafter referred to as an In layer) and a layer containing the element M, zinc (Zn), and oxygen (hereinafter referred to as an (M, Zn) layer) are stacked. Note that indium and the element M are mutually substituted. Therefore, the (M, Zn) layer may contain indium. The In layer may contain the element M. The In layer may contain Zn. The layered structure is observed as a lattice image in a high-resolution transmission electron microscope (TEM) image, for example.

[0450] When a CAAC-OS film is subjected to structural analysis using an XRD apparatus, for example, a peak indicating c-axis orientation is detected at or near 2θ = 31° in out-of-plane XRD measurement using θ / 2θ scanning. Note that the position of the peak indicating c-axis orientation (the value of 2θ) may vary depending on the type and composition of the metal elements constituting the CAAC-OS.

[0451] For example, multiple bright spots are observed in the electron diffraction pattern of a CAAC-OS film, and the observed spots are at positions that are point-symmetric with respect to a spot of an incident electron beam that has passed through the sample (also referred to as a direct spot).

[0452] When a crystalline region is observed from the specific direction, the lattice arrangement in the crystalline region is basically a hexagonal lattice, but the unit cell is not necessarily a regular hexagon and may be a non-regular hexagon. The distortion may have a pentagonal, heptagonal, or other lattice arrangement. In the CAAC-OS, no clear grain boundary can be identified even near the distortion. This indicates that the distortion in the lattice arrangement suppresses the formation of grain boundaries. This is thought to be because the CAAC-OS can tolerate distortion due to the lack of a dense arrangement of oxygen atoms in the a-b plane direction or the change in interatomic bond distance caused by metal atom substitution.

[0453] Note that a crystal structure in which clear grain boundaries are observed is called polycrystalline. The grain boundaries act as recombination centers, and are likely to trap carriers, resulting in a decrease in the on-state current of a transistor and a decrease in field-effect mobility. Therefore, CAAC-OS, in which clear grain boundaries are not observed, is one of the crystalline oxides having a crystal structure suitable for a semiconductor layer of a transistor. Note that a structure containing Zn is preferable for forming a CAAC-OS. For example, In—Zn oxide and In—Ga—Zn oxide are suitable because they can suppress the generation of grain boundaries more effectively than In oxide.

[0454] CAAC-OS is an oxide semiconductor with high crystallinity and no clear crystal grain boundaries. Therefore, it can be said that the CAAC-OS is less susceptible to a decrease in electron mobility due to crystal grain boundaries. Furthermore, since the crystallinity of an oxide semiconductor can be reduced by the inclusion of impurities or the generation of defects, the CAAC-OS can also be said to be an oxide semiconductor with few impurities and defects (such as oxygen vacancies). Therefore, an oxide semiconductor having a CAAC-OS has stable physical properties. Therefore, an oxide semiconductor having a CAAC-OS is heat-resistant and highly reliable. Furthermore, the CAAC-OS is stable even against high temperatures (so-called thermal budget) in the manufacturing process. Therefore, using a CAAC-OS for an OS transistor can increase the flexibility of the manufacturing process.

[0455] [nc-OS] The nc-OS has periodic atomic arrangement in a microscopic region (e.g., a region of 1 nm to 10 nm, particularly a region of 1 nm to 3 nm). In other words, the nc-OS has microcrystals. Note that the size of the microcrystals is, for example, 1 nm to 10 nm, particularly 1 nm to 3 nm, and therefore the microcrystals are also called nanocrystals. Furthermore, the nc-OS does not exhibit regularity in the crystal orientation between different nanocrystals. Therefore, no orientation is observed throughout the film. Therefore, depending on the analysis method, the nc-OS may be indistinguishable from an a-like OS or an amorphous oxide semiconductor. For example, when a structural analysis of an nc-OS film is performed using an XRD apparatus, no peak indicating crystallinity is detected in out-of-plane XRD measurement using θ / 2θ scanning. When an nc-OS film is subjected to electron diffraction (also referred to as selected-area electron diffraction) using an electron beam with a probe diameter larger than that of a nanocrystal (e.g., 50 nm or more), a diffraction pattern resembling a halo pattern is observed. On the other hand, when an nc-OS film is subjected to electron diffraction (also referred to as nanobeam electron diffraction) using an electron beam with a probe diameter close to or smaller than that of a nanocrystal (e.g., 1 nm to 30 nm), an electron diffraction pattern in which multiple spots are observed within a ring-shaped region centered on a direct spot may be obtained.

[0456] [a-Like OS] The a-like OS is an oxide semiconductor having a structure between the nc-OS and the amorphous oxide semiconductor. The a-like OS has a pore or low-density region. That is, the a-like OS has lower crystallinity than the nc-OS and the CAAC-OS. Furthermore, the a-like OS has a higher hydrogen concentration in the film than the nc-OS and the CAAC-OS.

[0457] <Structure of Oxide Semiconductor> Next, the above-described CAC-OS will be described in detail. Note that the CAC-OS relates to a material structure.

[0458] [CAC-OS] CAC-OS is, for example, a material in which elements constituting a metal oxide are unevenly distributed in a size of 0.5 nm to 10 nm, preferably 1 nm to 3 nm, or in the vicinity thereof. Note that hereinafter, a state in which one or more metal elements are unevenly distributed in a metal oxide and regions containing the metal elements are mixed in a size of 0.5 nm to 10 nm, preferably 1 nm to 3 nm, or in the vicinity thereof, is also referred to as a mosaic or patch state.

[0459] Furthermore, the CAC-OS has a mosaic structure in which a material is separated into a first region and a second region, and the first region is distributed throughout the film (hereinafter also referred to as a cloud structure). That is, the CAC-OS is a composite metal oxide having a structure in which the first region and the second region are mixed.

[0460] Here, the atomic ratios of In, Ga, and Zn to the metal elements constituting the CAC-OS in the In—Ga—Zn oxide are denoted as [In], [Ga], and [Zn], respectively. For example, in the CAC-OS in the In—Ga—Zn oxide, the first region is a region where [In] is larger than [In] in the composition of the CAC-OS film. The second region is a region where [Ga] is larger than [Ga] in the composition of the CAC-OS film. Alternatively, for example, the first region is a region where [In] is larger than [In] in the second region and [Ga] is smaller than [Ga] in the second region. The second region is a region where [Ga] is larger than [Ga] in the first region and [In] is smaller than [In] in the first region.

[0461] Specifically, the first region is a region whose main component is indium oxide, indium zinc oxide, or the like. The second region is a region whose main component is gallium oxide, gallium zinc oxide, or the like. In other words, the first region can be referred to as a region whose main component is In. The second region can be referred to as a region whose main component is Ga.

[0462] It should be noted that there are cases where a clear boundary between the first region and the second region cannot be observed.

[0463] CAC-OS in In—Ga—Zn oxide refers to a mosaic structure in which some regions mainly composed of Ga and other regions mainly composed of In are randomly arranged in a material composition containing In, Ga, Zn, and O. Therefore, it is presumed that CAC-OS has a structure in which metal elements are distributed nonuniformly.

[0464] The CAC-OS can be formed by sputtering without heating the substrate. When the CAC-OS is formed by sputtering, one or more of an inert gas (typically argon), oxygen gas, and nitrogen gas may be used as the deposition gas. The lower the flow rate of oxygen gas relative to the total flow rate of deposition gas during deposition, the more preferable it is. For example, the flow rate of oxygen gas relative to the total flow rate of deposition gas during deposition is preferably 0% or more and less than 30%, and more preferably 0% or more and 10% or less.

[0465] For example, in the case of CAC-OS in an In—Ga—Zn oxide, EDX mapping obtained using energy dispersive X-ray spectroscopy (EDX) can confirm that the CAC-OS has a structure in which a region containing In as a main component (first region) and a region containing Ga as a main component (second region) are unevenly distributed and mixed.

[0466] Here, the first region has higher conductivity than the second region. That is, the flow of carriers through the first region causes the metal oxide to exhibit conductivity. Therefore, the first region is distributed in a cloud-like manner in the metal oxide, thereby achieving a high field-effect mobility (μ).

[0467] On the other hand, the second region has higher insulating properties than the first region. That is, the second region is distributed in the metal oxide, thereby suppressing leakage current.

[0468] Therefore, when a CAC-OS is used in a transistor, the conductivity due to the first region and the insulating property due to the second region act complementarily, thereby providing the CAC-OS with a switching function (a function of turning on / off). In other words, a CAC-OS has a conductive function in a part of the material and an insulating function in a part of the material, and the entire material functions as a semiconductor. By separating the conductive function and the insulating function, both functions can be maximized. Therefore, by using a CAC-OS in a transistor, a high on-current (I ｏｎ ), high field-effect mobility (μ), and good switching behavior can be achieved.

[0469] A transistor using the CAC-OS has high reliability and is therefore ideal for various semiconductor devices such as display devices.

[0470] Oxide semiconductors have a variety of structures, each of which has different characteristics. The oxide semiconductor of one embodiment of the present invention may include two or more of an amorphous oxide semiconductor, a polycrystalline oxide semiconductor, an a-like OS, a CAC-OS, an nc-OS, and a CAAC-OS.

[0471] <Transistor Having Oxide Semiconductor> Next, a case where the oxide semiconductor is used for a transistor will be described.

[0472] By using the oxide semiconductor for a transistor, a transistor with high field-effect mobility and high reliability can be realized.

[0473] For the transistor, an oxide semiconductor having a low carrier concentration is preferably used. For example, the carrier concentration of the oxide semiconductor is 1×10 １７ cm −３ Below 1 × 10, preferably １５ cm −３ More preferably, 1×10 １３ cm −３ or less, more preferably 1 × 10 １１ cm −３ More preferably, 1×10 １０cm −３ is less than 1×10 −９ cm −３ That is all. Note that in order to reduce the carrier concentration of an oxide semiconductor film, the impurity concentration in the oxide semiconductor film may be reduced to reduce the density of defect states. In this specification and the like, a semiconductor having a low impurity concentration and a low density of defect states is referred to as a highly purified intrinsic or substantially highly purified intrinsic oxide semiconductor. Note that an oxide semiconductor having a low carrier concentration may also be referred to as a highly purified intrinsic or substantially highly purified intrinsic oxide semiconductor.

[0474] A highly purified intrinsic or substantially highly purified intrinsic oxide semiconductor film has a low density of defect states, and therefore, the density of trap states may also be low.

[0475] Charges trapped in the trap states of an oxide semiconductor take a long time to dissipate and may behave like fixed charges. Therefore, a transistor in which a channel formation region is formed in an oxide semiconductor with a high density of trap states may have unstable electrical characteristics.

[0476] Therefore, in order to stabilize the electrical characteristics of a transistor, it is effective to reduce the impurity concentration in the oxide semiconductor. Furthermore, in order to reduce the impurity concentration in the oxide semiconductor, it is preferable to also reduce the impurity concentration in the adjacent film. Impurities include hydrogen, nitrogen, alkali metals, alkaline earth metals, iron, nickel, silicon, and the like.

[0477] <Impurities> Here, the influence of each impurity in an oxide semiconductor will be described.

[0478] When an oxide semiconductor contains silicon or carbon, which is one of Group 14 elements, defect levels are formed in the oxide semiconductor. Therefore, the concentration of silicon or carbon in the oxide semiconductor and the concentration of silicon or carbon near the interface with the oxide semiconductor (concentration obtained by secondary ion mass spectrometry (SIMS)) are set to 2×10 １８ atoms / cm ３ Below 2 × 10, preferably １７ atoms / cm ３ The following applies.

[0479] When an oxide semiconductor contains an alkali metal or an alkaline earth metal, defect levels may be formed and carriers may be generated. Therefore, a transistor using an oxide semiconductor containing an alkali metal or an alkaline earth metal is likely to have normally-on characteristics. For this reason, when the concentration of the alkali metal or the alkaline earth metal in the oxide semiconductor obtained by SIMS is 1×10 １８ atoms / cm ３ Below 2 × 10, preferably １６ atoms / cm ３ Do the following:

[0480] When nitrogen is contained in an oxide semiconductor, electrons serving as carriers are generated, the carrier concentration increases, and the semiconductor is likely to become n-type. As a result, a transistor using an oxide semiconductor containing nitrogen as a semiconductor tends to have normally-on characteristics. Alternatively, when nitrogen is contained in an oxide semiconductor, trap states may be formed. As a result, the electrical characteristics of the transistor may become unstable. For this reason, the nitrogen concentration in the oxide semiconductor obtained by SIMS is measured to be 5×10 １９ atoms / cm ３ Less than 5×10 １８ atoms / cm ３ or less, more preferably 1 × 10 １８ atoms / cm ３ or less, more preferably 5 × 10 １７ atoms / cm ３ Do the following:

[0481] Hydrogen contained in an oxide semiconductor reacts with oxygen bonded to a metal atom to form water, which may form an oxygen vacancy. Hydrogen entering the oxygen vacancy may generate electrons as carriers. Furthermore, some of the hydrogen may bond with oxygen bonded to a metal atom to generate electrons as carriers. Therefore, a transistor using an oxide semiconductor containing hydrogen is likely to have normally-on characteristics. Therefore, it is preferable to reduce the amount of hydrogen in the oxide semiconductor as much as possible. Specifically, the hydrogen concentration in the oxide semiconductor measured by SIMS is 1×10 ２０ atoms / cm３ less than 1×10 １９ atoms / cm ３ less than 5×10 １８ atoms / cm ３ less than 1×10 １８ atoms / cm ３ Make it less than.

[0482] When an oxide semiconductor with sufficiently reduced impurities is used for a channel formation region of a transistor, stable electrical characteristics can be obtained.

[0483] This embodiment mode can be combined with other embodiment modes as appropriate.

[0484] Embodiment 5 In this embodiment, electronic devices of one embodiment of the present invention will be described with reference to FIGS.

[0485] An electronic device according to one embodiment of the present invention can capture an image or detect a touch operation using a display portion, thereby improving the functionality and convenience of the electronic device.

[0486] Examples of electronic devices according to one embodiment of the present invention include electronic devices with relatively large screens, such as television sets, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound reproduction devices.

[0487] An electronic device according to one embodiment of the present invention may have a sensor (including a function for measuring 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).

[0488] An electronic device of one embodiment of the present invention can have various functions, such as a function to display various information (still images, videos, text images, and the like) on a display portion, a touch panel function, a function to display a calendar, date, time, and the like, a function to execute various software programs (programs), a wireless communication function, a function to read programs or data recorded on a recording medium, and the like.

[0489] The electronic device 6500 shown in FIG. 16A is a portable information terminal that can be used as a smartphone.

[0490] The electronic device 6500 includes a housing 6501, a display portion 6502, a power button 6503, operation buttons 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.

[0491] The display device described in Embodiment 2 or 3 can be applied to the display portion 6502 .

[0492] FIG. 16B is a schematic cross-sectional view including the end of the housing 6501 on the microphone 6506 side.

[0493] 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.

[0494] 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).

[0495] 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.

[0496] 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.

[0497] When the display device described in Embodiment Mode 2 is used for the display panel 6511, an image can be captured in the display portion 6502. For example, a fingerprint can be captured on the display panel 6511 and fingerprint authentication can be performed.

[0498] The display portion 6502 further includes a touch sensor panel 6513, which allows the display portion 6502 to have a touch panel function. The touch sensor panel 6513 can use various types such as a capacitive type, a resistive type, a surface acoustic wave type, an infrared type, an optical type, or a pressure-sensitive type. Alternatively, the display panel 6511 may function as a touch sensor, in which case the touch sensor panel 6513 is not necessarily provided.

[0499] 17A 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.

[0500] The display device described in Embodiment 2 can be applied to the display portion 7000 .

[0501] 17A can be operated using an operation switch provided on the housing 7101 or 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.

[0502] The television device 7100 is configured to include 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.

[0503] 17B 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.

[0504] The display device described in Embodiment 2 can be applied to the display portion 7000 .

[0505] 17C and 17D show an example of digital signage.

[0506] 17C 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.

[0507] 17D 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.

[0508] 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.

[0509] 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.

[0510] 17C and 17D , 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. Furthermore, by operating the information terminal 7311 or the information terminal 7411, the display on the display unit 7000 can be switched.

[0511] 17C and 17D, the display device described in Embodiment Mode 2 can be applied to the display portion of an information terminal 7311 or an information terminal 7411.

[0512] It is also possible to cause the digital signage 7300 or the digital signage 7400 to execute 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.

[0513] The electronic device shown in Figures 18A to 18F 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, 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), a microphone 9008, etc.

[0514] The electronic devices shown in Figures 18A to 18F 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 the display unit, etc.

[0515] The electronic devices shown in FIGS. 18A to 18F will be described in detail below.

[0516] FIG. 18A 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. 18A 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 the strength of antenna reception. Alternatively, an icon 9050 or the like may be displayed in the position where the information 9051 is displayed.

[0517] 18B 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.

[0518] FIG. 18C 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.

[0519] 18D to 18F are perspective views showing a foldable mobile information terminal 9201. FIG. 18D is a perspective view of the mobile information terminal 9201 in an unfolded state, FIG. 18F is a perspective view of the mobile information terminal 9201 in a folded state, and FIG. 18E is a perspective view of a state in the process of changing from one of FIG. 18D and FIG. 18F 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. A display unit 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by hinges 9055. For example, the display unit 9001 can be bent with a curvature radius of 0.1 mm or more and 150 mm or less.

[0520] This embodiment mode can be combined with other embodiment modes as appropriate.

[0521] In this example, a light-receiving device was fabricated and its characteristics were evaluated. The light-receiving devices fabricated in the following examples all share a common structure with light-emitting devices, and have a stacked structure that can be fabricated by replacing the light-emitting layer of the light-emitting device with the active layer of the light-receiving device. Furthermore, by adding a light-emitting layer of the light-emitting device, the device has a stacked structure that can function as a light-receiving and light-emitting device.

[0522] In this example, a light-receiving device (device A) according to one embodiment of the present invention and a light-receiving device (comparative device B) as a comparative example were fabricated.

[0523] The chemical formulas of the materials used in this example are shown below.

[0524]

[0525] The specific configuration of the light-receiving device fabricated in this example is shown in Tables 1 and 2. The configuration of the light-receiving device can be that of the light-receiving device 10 illustrated in FIG. 1E. The light-receiving device fabricated in this example had the same configuration as the light-receiving device 10 except for the configuration of the active layer 23.

[0526]

[0527]

[0528] The first electrode 11 was formed by forming a film of an alloy of silver, palladium, and copper (APC: Ag-Pd-Cu) by sputtering to a thickness of 100 nm, and then forming a film of indium tin oxide containing silicon oxide (ITSO) by sputtering to a thickness of 100 nm.

[0529] Next, the substrate on which the first electrode 11 was formed was washed with water, baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds. −４ The substrate was introduced into a vacuum deposition apparatus whose internal pressure had been reduced to about Pa, and vacuum baking was performed at 170° C. for 30 minutes in a heating chamber of the vacuum deposition apparatus. Thereafter, the substrate was allowed to cool for about 30 minutes.

[0530] The layer 21 a functioning as a hole transport layer was formed by co-evaporating N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf) and a fluorine-containing electron acceptor material (OCHD-003) having a molecular weight of 672 in a weight ratio of BBABnf:OCHD-003=1:0.1. The layer 21 a was formed to a thickness of 10 nm.

[0531] The layer 21b functioning as a hole transport layer was formed by vapor deposition of BBABnf to a film thickness of 40 nm.

[0532] The active layer 23 of device A, which is one embodiment of the present invention, was formed by co-evaporating 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) represented by the above structural formula (126) and Rubrene represented by the above structural formula (201) in a weight ratio of 5:5. The active layer 23 was formed to a thickness of 60 nm.

[0533] The active layer 23 of the comparative device B is made of fullerene C ７０ and tetraphenyldibenzoperiflanthene (abbreviation: DBP) in a weight ratio of C ７０ The active layer 23 was formed by co-evaporation so that the ratio of SiO 2 to DBP was 9:1. The active layer 23 was formed to a film thickness of 60 nm.

[0534] In addition, fullerene C used in the active layer 23 of the comparative device B ７０ The deposition temperature of FT2TDMN is approximately 600° C., and the deposition temperature of DBP is approximately 400° C. In contrast, the deposition temperatures of FT2TDMN used in the active layer 23 of Device A, which is one embodiment of the present invention, are low, at approximately 250° C., and the deposition temperature of Rubrene is approximately 200° C. Therefore, by using the configuration of the optical device, which is one embodiment of the present invention, optical devices can be manufactured with high productivity.

[0535] The layer 25a functioning as an electron transport layer was formed by evaporating 2-[3′-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II) to a thickness of 10 nm, followed by evaporating 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen) to a thickness of 10 nm.

[0536] The layer 25b functioning as an electron transport layer was formed by vapor deposition of lithium fluoride (LiF) to a thickness of 1 nm.

[0537] The second electrode 13 was formed by co-evaporating silver (Ag) and magnesium (Mg) at a volume ratio of 10:1 to form a film having a thickness of 10 nm, and then forming indium tin oxide (ITO) by a sputtering method to form a film having a thickness of 40 nm.

[0538] In this manner, device A and comparative device B, each having a different configuration of the active layer 23, were fabricated.

[0539] <Current-Voltage Characteristics> Next, the current-voltage characteristics of each light-receiving device were measured. The measurements were performed using monochromatic light with a wavelength of 525 nm at an irradiance of 12.5 μW / cm ２ The measurements were performed under illumination (denoted as Photo) and in the dark (denoted as Dark), respectively. The current-voltage characteristics of Device A and Comparative Device B are shown in Figure 19A. In Figure 19A, the horizontal axis represents voltage V and the vertical axis represents current I.

[0540] As shown in FIG. 19A, it was confirmed that all the light-receiving devices exhibited good saturation characteristics.

[0541] The wavelength dependence of the external quantum efficiency (EQE) is shown in Figure 19B. The EQE was measured at a voltage of -4 V and an irradiance of 12.5 μW / cm ２ 19B, the horizontal axis represents wavelength λ and the vertical axis represents EQE.

[0542] As shown in FIG. 19B, it was confirmed that all of the light-receiving devices had light-receiving sensitivity in the wavelength range of 450 nm or more and 650 nm or less.

[0543] In this example, a light-receiving device was fabricated and its characteristics were evaluated. The results are described below.

[0544] In this example, light-receiving devices according to one embodiment of the present invention (Devices 1a to 1d, Devices 2a to 2d) and comparative light-receiving devices (Comparative Devices 1A to 1C, Comparative Devices 2A to 2C) were fabricated.

[0545] The chemical formulas of the materials used in this example are shown below.

[0546]

[0547] The specific configuration of the light-receiving device fabricated in this example is shown in Tables 3 and 4. The configuration of the light-receiving device can be that of the light-receiving device 10 illustrated in FIG. 1E. The light-receiving device fabricated in this example had the same configuration as the light-receiving device 10 except for the configurations of the active layer 23 and the layer 25a.

[0548] The light-receiving device of this embodiment is similar to the light-receiving device of Example 1, except that the configurations of the active layer 23 and the layer 25a are changed. Therefore, with regard to the method of manufacturing the light-receiving device of this embodiment, Example 1 can be referred to for the parts that are similar to the light-receiving device of Example 1.

[0549]

[0550]

[0551] The first electrode 11, the layer 21a, and the layer 21b were formed. Since the description of Example 1 can be referred to for the formation of the first electrode 11, the layer 21a, and the layer 21b, detailed description thereof will be omitted.

[0552] The active layer 23 of each of Devices 1a to 1d and 2a to 2d, which are embodiments of the present invention, was formed by co-evaporation of FT2TDMN represented by the structural formula (126) and Rubrene represented by the structural formula (201) at a weight ratio of 9:1. The active layer 23 was formed to a thickness of 60 nm.

[0553] The active layer 23 of the comparative devices 1A to 1C and 2A to 2C, which are comparative examples, contains fullerene C ７０ and tetraphenyldibenzoperiflanthene (abbreviation: DBP) in a weight ratio of C ７０ The active layer 23 was formed by co-evaporation so that the ratio of SiO 2 to DBP was 9:1. The active layer 23 was formed to a film thickness of 60 nm.

[0554] In Devices 1a to 1d, which are embodiments of the present invention, and Comparative Devices 1A to 1C, which are comparative examples, the layer 25a functioning as an electron-transport layer was formed by evaporating 2-[3′-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II) and then evaporating 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen) to a thickness of 10 nm.

[0555] In Devices 2a to 2d, which are embodiments of the present invention, and Comparative Devices 2A to 2C, which are comparative examples, the layer 25a functioning as an electron-transport layer was formed by evaporating 2-[4′-(9-phenyl-9H-carbazol-3-yl)-3,1′-biphenyl-1-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mpPCBPDBq) and then evaporating 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen) to a thickness of 10 nm.

[0556] A layer 25b functioning as an electron transport layer and a second electrode 13 were formed. The details of the formation of the layer 25b and the second electrode 13 can be referred to in Example 1, and therefore will not be described in detail again.

[0557] As described above, devices 1a to 1d, 2a to 2d, comparative devices 1A to 1C, and comparative devices 2A to 2C each having a different configuration of the active layer 23 and layer 25a were fabricated.

[0558] <Current-Voltage Characteristics> Next, the current-voltage characteristics of each light-receiving device were measured. The measurements were performed using monochromatic light with a wavelength of 525 nm at an irradiance of 12.5 μW / cm ２ 20A and 20B show the relationship between the voltage when the current is 20 nA or more and the film thickness of the layer 25a in the current-voltage characteristics. The voltage when the current is 20 nA or more corresponds to the drive voltage of the light-receiving device.

[0559] 20A shows data for Devices 1a to 1d and 2a to 2d according to one embodiment of the present invention, and FIG. 20B shows data for Comparative Devices 1A to 1D and 2A to 2D according to comparative examples. In FIG. 20A and FIG. 20B, the horizontal axis represents the thickness X of layer 25a, and the vertical axis represents the voltage Dr at which the current becomes 20 nA or greater.

[0560] As shown in Figure 20A, it was confirmed that the change in voltage Dr with respect to the material and film thickness of layer 25a was small in the light-receiving device according to one embodiment of the present invention. On the other hand, as shown in Figure 20B, it was confirmed that the change in voltage Dr with respect to the material and film thickness of layer 25a was large in the light-receiving device according to the comparative example. Furthermore, compared to the light-receiving device according to the comparative example, the absolute value of voltage Dr in the light-receiving device according to one embodiment of the present invention was small, from about 0.35 V to about 0.60 V, and it was confirmed that the driving voltage was low.

[0561] In this example, a light-receiving device was fabricated and its characteristics were evaluated. The results are described below.

[0562] In this example, light-receiving devices according to one embodiment of the present invention (devices 3a to 3d, devices 4a to 4d, devices 5a to 5d, and devices 6a to 6d) were fabricated.

[0563] The light-receiving device of this embodiment is similar to the light-receiving device of Example 1, except that the configurations of the active layer 23 and the layer 25a are changed. Therefore, with regard to the method of manufacturing the light-receiving device of this embodiment, Example 1 can be referred to for the parts that are similar to the light-receiving device of Example 1.

[0564] The chemical formulas of the materials used in this example are shown below.

[0565]

[0566] The specific configuration of the light-receiving device fabricated in this example is shown in Tables 5 and 6. The configuration of the light-receiving device can be that of the light-receiving device 10 illustrated in FIG. 1E. The light-receiving device fabricated in this example had the same configuration as the light-receiving device 10 except for the configurations of the active layer 23 and the layer 25a.

[0567]

[0568]

[0569] The first electrode 11, the layer 21a, and the layer 21b were formed. Since the description of Example 1 can be referred to for the formation of the first electrode 11, the layer 21a, and the layer 21b, detailed description thereof will be omitted.

[0570] The active layer 23 was formed by co-evaporating FT2TDMN represented by the structural formula (126) above and Rubrene represented by the structural formula (201) above at a weight ratio of 7:3. The film thickness of the active layer 23 was varied among the samples.

[0571] Layer 25a functioning as an electron transport layer was formed by evaporating 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II) and then co-evaporating 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen) and Liq to a thickness of 10 nm and a weight ratio of 1:1. The thickness of 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II) was varied among the samples.

[0572] The second electrode 13 was formed by co-evaporating silver (Ag) and magnesium (Mg) at a volume ratio of 10:1 to form a film having a thickness of 10 nm.

[0573] As described above, devices 3a to 3d, 4a to 4d, 5a to 5d, and 6a to 6d each having a different configuration of the active layer 23 and layer 25a were fabricated.

[0574] <Current Density-Voltage Characteristics> Next, the current density-voltage characteristics of each light-receiving device were measured. The measurements were performed using monochromatic light with a wavelength of 525 nm at an irradiance of 12.5 μW / cm ２ The measurements were performed under illumination (denoted as Photo) and in the dark (denoted as Dark), respectively. The current density-voltage characteristics of Devices 3a to 3d are shown in FIGS. 21A and 21B . The current density-voltage characteristics of Devices 4a to 4d are shown in FIGS. 22A and 22B . The current density-voltage characteristics of Devices 5a to 5d are shown in FIGS. 23A and 23B . The current density-voltage characteristics of Devices 6a to 6d are shown in FIGS. 24A and 24B . In FIGS. 21A to 24B , the horizontal axis represents voltage V, and the vertical axis represents current density J.

[0575] As shown in FIGS. 21A to 24B, it was confirmed that all of the light-receiving devices exhibited good saturation characteristics.

[0576] The wavelength dependence of the external quantum efficiency (EQE) of Devices 3a to 3d is shown in FIG. 25A. The wavelength dependence of the external quantum efficiency (EQE) of Devices 4a to 4d is shown in FIG. 25B. The wavelength dependence of the external quantum efficiency (EQE) of Devices 5a to 5d is shown in FIG. 26A. The wavelength dependence of the external quantum efficiency (EQE) of Devices 6a to 6d is shown in FIG. 26B. The EQE was measured at a voltage of −4 V and an irradiance of 12.5 μW / cm. ２ 25A to 26B, the horizontal axis represents wavelength λ and the vertical axis represents EQE.

[0577] As shown in FIGS. 25A to 26B, it was confirmed that when the thickness of the active layer 23 is 60 nm or more, the change in light-receiving sensitivity due to the thickness of the layer 25a is small.

[0578] In this example, a light-receiving device was fabricated and its characteristics were evaluated. The results are described below.

[0579] In this example, light-receiving devices according to one embodiment of the present invention (devices 7a to 7d, devices 8a to 8d, devices 9a to 9d, and devices 10a to 10d) were fabricated.

[0580] The chemical formulas of the materials used in this example are shown below.

[0581]

[0582] The specific configuration of the light-receiving device fabricated in this example is shown in Tables 7 and 8. The configuration of the light-receiving device can be that of the light-receiving device 10 illustrated in FIG. 1E. The light-receiving device fabricated in this example had the same configuration as the light-receiving device 10 except for the configurations of the active layer 23 and the layer 21b.

[0583]

[0584]

[0585] The first electrode 11 and the layer 21a were formed. Since the description of Example 1 can be referred to for the formation of the first electrode 11 and the layer 21a, detailed description thereof will be omitted.

[0586] In Devices 6a to 6d and Devices 7a to 7d, the layer 21b functioning as a hole-transporting layer was formed by evaporating N-(1,1′-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF). The thickness of the layer 21b was varied depending on the sample.

[0587] In Devices 8a to 8d and Devices 9a to 9d, the layer 21b functioning as a hole transport layer was formed by vapor deposition of BBABnf. The thickness of the layer 21b varied depending on the sample.

[0588] The active layer 23 was formed by co-evaporating FT2TDMN represented by the structural formula (126) above and Rubrene represented by the structural formula (201) above at a weight ratio of 7:3. The film thickness of the active layer 23 was varied among the samples.

[0589] The layer 25a functioning as an electron transport layer was formed by evaporating 2-[3′-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II) to a thickness of 15 nm, followed by co-evaporating 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen) and Liq to a thickness of 25 nm and a weight ratio of 1:1.

[0590] The second electrode 13 was formed by co-evaporating silver (Ag) and magnesium (Mg) at a volume ratio of 10:1 to form a film having a thickness of 10 nm.

[0591] As described above, devices 6a to 6d, 7a to 7d, 8a to 8d, and 9a to 9d each having a different active layer 23 and layer 21b configuration were fabricated.

[0592] <Current Density-Voltage Characteristics> Next, the current density-voltage characteristics of each light-receiving device were measured. The measurements were performed using monochromatic light with a wavelength of 525 nm at an irradiance of 12.5 μW / cm ２ The measurements were performed under illumination (denoted as Photo) and in the dark (denoted as Dark), respectively. The current density-voltage characteristics of Devices 7a to 7d are shown in FIGS. 27A and 27B . The current density-voltage characteristics of Devices 8a to 8d are shown in FIGS. 28A and 28B . The current density-voltage characteristics of Devices 9a to 9d are shown in FIGS. 29A and 29B . The current density-voltage characteristics of Devices 10a to 10d are shown in FIGS. 30A and 30B . In FIGS. 27A to 30B , the horizontal axis represents voltage V, and the vertical axis represents current density J.

[0593] As shown in FIGS. 27A to 30B, it was confirmed that all of the light-receiving devices exhibited good saturation characteristics.

[0594] The wavelength dependence of the external quantum efficiency (EQE) of Devices 7a to 7d is shown in FIG. 31A. The wavelength dependence of the external quantum efficiency (EQE) of Devices 8a to 8d is shown in FIG. 31B. The wavelength dependence of the external quantum efficiency (EQE) of Devices 9a to 9d is shown in FIG. 32A. The wavelength dependence of the external quantum efficiency (EQE) of Devices 10a to 10d is shown in FIG. 32B. The EQE was measured at a voltage of −4 V and an irradiance of 12.5 μW / cm. ２ 31A to 32B, the horizontal axis represents wavelength λ and the vertical axis represents EQE.

[0595] As shown in FIGS. 31A to 32B, it was confirmed that good light-receiving sensitivity could be obtained when the film thickness of the layer 21b was 40 nm or more.

[0596] In this example, a light-receiving device was fabricated and its reliability was evaluated. The results are described below.

[0597] In this example, light-receiving devices (devices 11a to 11d) according to one embodiment of the present invention were fabricated.

[0598] The chemical formulas of the materials used in this example are shown below.

[0599]

[0600] The specific configuration of the light-receiving device fabricated in this example is shown in Tables 9 and 10. The configuration of the light-receiving device can be that of the light-receiving device 10 illustrated in FIG. 1E. The light-receiving device fabricated in this example had the same configuration as the light-receiving device 10 except for the configuration of the layer 25a.

[0601]

[0602]

[0603] The first electrode 11 and the layer 21a were formed. Since the description of Example 1 can be referred to for the formation of the first electrode 11 and the layer 21a, detailed description thereof will be omitted.

[0604] The layer 21b functioning as a hole transport layer was formed by vapor deposition of BBABnf to a thickness of 40 nm.

[0605] The active layer 23 was formed by co-evaporating FT2TDMN represented by the structural formula (126) above and Rubrene represented by the structural formula (201) above at a weight ratio of 9: 1. The active layer 23 was formed to a film thickness of 60 nm.

[0606] The layer 25a functioning as an electron transport layer was formed by evaporating 2-[3′-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II) and then co-evaporating 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen) and Liq to a thickness of 25 nm and a weight ratio of 1:1. The thickness of the 2-[3′-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II) was varied among the samples.

[0607] The second electrode 13 was formed by co-evaporating silver (Ag) and magnesium (Mg) at a volume ratio of 10:1 to form a film having a thickness of 10 nm.

[0608] In this manner, devices 11a to 11d each having a different structure of the layer 25a were fabricated.

[0609] <Reliability> Next, the reliability of each light-receiving device was evaluated. To evaluate the reliability, a white LED was used to irradiate the light-receiving device with 5000K light at an illuminance of 100 klux, and the current was measured while maintaining the device at a voltage of -4 V and a temperature of 25°C. The measurement results for each light-receiving device are shown in FIG. 33. In FIG. 33, the horizontal axis represents time, and the vertical axis represents normalized current. The normalized current is a value when the initial current value is set to 1.

[0610] 33, it was confirmed that all of the light-receiving devices had high reliability. In particular, it was confirmed that good reliability was obtained in device 11b, in which the layer 25a had a thickness of 40 nm, and device 11c, in which the layer 25a had a thickness of 70 nm.

[0611] MS: wiring, PD: light-receiving device, RES: wiring, SE: wiring, TX: wiring, VG: wiring, VS: wiring, 10a: device, 10A: light-receiving and light-emitting device, 10d: device, 10: light-receiving device, 11: first electrode, 13: second electrode, 15: layer, 21a: layer, 21b: layer, 21: hole-transport layer, 23a: first layer, 23b: second layer, 23: active layer, 25a: layer, 25b: layer, 25: electron-transport layer, 31: hole-injection layer, 35: electron-injection layer, 39: light-emitting layer, 100A: display device, 100B: display device, 100C: display device, 100D: display device, 100E: Display device, 110: light receiving device, 112: common layer, 114: common layer, 115: common electrode, 116: protective layer, 121B: light, 121G: light, 121R: light, 121: visible light, 122: light, 123a: stray light, 123b: stray light, 123: light, 124: reflected light, 131: transistor, 132: transistor, 142: adhesive layer, 151: substrate, 152: substrate, 153: substrate, 154: substrate, 155: adhesive layer, 156: adhesive layer, 157: insulating layer, 158: light-shielding layer, 159p: opening, 159: resin layer, 162: display section, 164: circuit, 165: wiring, 166: conductor layer, 167: conductive layer, 169: conductive layer, 172: FPC, 173: IC, 182: buffer layer, 183: active layer, 184: buffer layer, 190B: light-emitting device, 190G: light-emitting device, 190R: light-emitting device, 190RPD: light-receiving / light-emitting device, 190: light-emitting device, 191: pixel electrode, 192B: buffer layer, 192G: buffer layer, 192R: buffer layer, 192: buffer layer, 193B: light-emitting layer, 193G: light-emitting layer, 193R: light-emitting layer, 193: light-emitting layer, 194B: buffer layer, 194G: buffer layer, 194R: buffer layer, 194: buffer buffer layer, 200A: display device, 200B: display device, 201: substrate, 202: finger, 203: layer, 204: layer, 205: functional layer, 207: layer, 208: stylus, 209: substrate, 211: insulating layer, 212: insulating layer, 213: insulating layer, 214a: insulating layer, 214b: insulating layer, 214: insulating layer, 215: insulating layer, 216: partition wall, 219a: light-shielding layer, 219b: spacer, 221: conductive layer, 222a: conductive layer, 222b: conductive layer, 223: conductive layer, 225: insulating layer, 228: region, 231i: channel formation region, 231n: low-resistance region, 231: semiconductor layer,240: transistor, 241: transistor, 242: connection layer, 243: transistor, 244: connection portion, 245: transistor, 246: transistor, 247: transistor, 248: transistor, 249: transistor, 261: contact portion, 262: fingerprint, 263: imaging range, 266: trajectory, 270B: light emitting device, 270G: light emitting device, 270PD: light receiving device, 270R: light emitting device, 270RPD: light receiving / emitting device, 270: light emitting device, 271: first electrode, 273: active layer, 275: second electrode, 2 80A: display device, 280B: display device, 280C: display device, 280D: display device, 280E: display device, 280F: display device, 280G: display device, 280H: display device, 281: hole injection layer, 282: hole transport layer, 283B: light emitting layer, 283G: light emitting layer, 283R: light emitting layer, 283: light emitting layer, 284a: first electron transport layer, 284b: second electron transport layer, 284: electron transport layer, 285: electron injection layer, 6500: electronic device, 6501: housing, 6502: display unit, 6503: power button, 6504: button, 6505: speaker, 6 506: 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, 7103: 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: mobile information terminal, 9102: mobile information terminal, 9200: mobile information terminal, 9201: mobile information terminal,

Claims

1. A device comprising an anode, a cathode, an active layer, and an electron transport layer, the active layer is located between the anode and the cathode; the active layer comprises a first organic compound and a second organic compound; The first organic compound is represented by general formula (G1), The second organic compound is represented by general formula (G2-1), the electron transport layer is located between the cathode and the active layer; The optical device, wherein the electron transport layer has a thickness of 10 nm or more and 300 nm or less. 【Chemistry 1】 (In the general formula (G1), D １ represents a substituted or unsubstituted thiophene-diyl group, a substituted or unsubstituted furan-diyl group, a heteroarylene group having 4 to 30 carbon atoms containing a substituted or unsubstituted thiophene, or a heteroarylene group having 4 to 30 carbon atoms containing a substituted or unsubstituted furan; Ar １ and Ar ２ each independently represents a substituted or unsubstituted heteroarylene group having 4 to 30 carbon atoms, or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms; A １ and A ２ each independently represents hydrogen, deuterium, a nitro group, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a vinyl group having 1 to 3 substituents, the substituents being a cyano group, a halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a nitro group; １ , n １ , k １ Each independently represents an integer of 0 to 3; m １ , n １ , and k １ At least one of R represents an integer of 1 to 3. １ ~R １０ each independently represents hydrogen, deuterium, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, a halogen, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, a cyano group, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms; ２ represents an integer from 1 to 5.

2. In claim 1, Said m ２ is 2 or more, A plurality of the R ９ are different optical devices.

3. In claim 1 or 2, Said m ２ is 2 or more, A plurality of the R １０ are different optical devices.

4. In any one of claims 1 to 3, The R １ or the above R ４ and the R ５ or the above R ８ wherein at least one pair of adjacent groups are bonded to each other to form a ring.

5. In any one of claims 1 to 4, The second organic compound is an optical device represented by structural formula (201) or (202). 【Chemistry 2】

6. In any one of claims 1 to 5, The above D １ is represented by any one of general formulas (g1-1-1) to (g1-1-4), The Ar １ and the Ar ２ each independently represents a substituted or unsubstituted thiophene-diyl group, a substituted or unsubstituted furan-diyl group, a substituted or unsubstituted phenylene group, or a substituted or unsubstituted naphthalene-diyl group, The above A １ and A ２ each independently represents an optical device represented by general formula (g1-2). 【Chemistry 3】 (However, in general formulae (g1-1-1) to (g1-1-4) and general formula (g1-2), R １０１ and R １０２ One of them is Ar １ and Ar ２ and R １０３ and R １０４ One of them is Ar １ and Ar ２ and R １０５ and R １０６ One of them is Ar １ and Ar ２ and R １０７ and R １０８ One of them is Ar １ and Ar ２ and R １０９ and R １１０ One of them is Ar １ and Ar ２ and R １１１ and R １１２ One of them is Ar １ and Ar ２ and R １１３ ~R １１６ Either one of the two is Ar １ and the other is Ar ２ and R １０１ ~R １１６ the remainders each independently represent hydrogen, deuterium, a linear alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a linear halogenated alkyl group having 1 to 6 carbon atoms, or a halogen; R １１７ ~R １１９ each independently represents hydrogen, deuterium, a cyano group, fluorine, chlorine, a nitro group, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms; R １１７ ~R １１９ at least one of R represents a cyano group, a fluorine group, a chlorine group, a nitro group, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms; １２０ is Ar １ and Ar ２ and X １ ~X １４ Each independently represents oxygen or sulfur; n １１ represents an integer from 0 to 10; １２ and n １３ each independently represents an integer of 0 to 4.

7. In any one of claims 1 to 5, The first organic compound is an optical device represented by any one of general formulas (G1-1) to (G1-3). 【Chemistry 4】 (In the general formulae (G1-1) to (G1-3), X １５ ~X ３０ Each independently represents oxygen or sulfur; n １４ and n １７ Each independently represents an integer of 0 to 4; １５ , n １６ , n １８ , n １９ 〜n ２２ Each independently represents an integer of 0 to 3; ２０ 〜n ２２ At least one of R represents an integer of 1 to 3; １２７ ~R １３２ , and R １３９ ~R １５０ each independently represents hydrogen, deuterium, a linear alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms, a linear halogenated alkyl group having 1 to 6 carbon atoms, or a halogen; R １２１ ~R １２６ , and R １３３ ~R １３８ , and R １６０ ~R １６５ each independently represents hydrogen, deuterium, a cyano group, fluorine, chlorine, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms; R １２１ ~R １２６ At least one of and R １３３ ~R １３８ At least one of and R １６０ ~R １６５ At least one of represents a cyano group, a fluorine group, a chlorine group, a nitro group, a substituted or unsubstituted halogenated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms.

8. In any one of claims 1 to 5, The first organic compound is an optical device represented by any one of structural formulas (126) and (137). 【Chemistry 9】

9. In any one of claims 1 to 8, An optical device having a light emitting layer in contact with the active layer on the anode side.

10. In any one of claims 1 to 8, An optical device having a light emitting layer in contact with the cathode side of the active layer.

11. In any one of claims 1 to 10, a hole transport layer between the anode and the active layer; The optical device, wherein the thickness of the hole transport layer is 10 nm or more and 300 nm or less.

12. In any one of claims 1 to 10, a hole transport layer between the anode and the active layer; The optical device, wherein the thickness of the hole transport layer is 40 nm or more and 300 nm or less.

13. In any one of claims 1 to 12, the active layer includes a first layer and a second layer; the first layer has a region in contact with the second layer, the first layer comprises the first organic compound; The second layer comprises the second organic compound.

14. In any one of claims 1 to 13, An optical device, wherein the active layer has a thickness of 60 nm or more.

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