Display apparatus and electronic equipment
Patent Information
- Application Number
- JP2022581031
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2021-03-31
- Filing Date
- 2022-02-01
- Publication Date
- 2025-01-14
- Estimated Expiration
- 2042-02-01
AI Technical Summary
Existing display devices face challenges in providing a convenient, useful, and reliable solution for efficiently connecting and powering multiple pixel circuits and light emitting devices, leading to complex wiring and potential connection failures.
The use of multiple conductive films and pads to facilitate signal and power supply to pixel circuits and light emitting devices, allowing for efficient connection and reduced wiring complexity, with conductive films intersecting to select and power specific pixel circuits and light emitting devices.
This configuration enables a novel display device with improved convenience, usefulness, and reliability by simplifying the connection process and reducing the risk of connection failures, while allowing for efficient power distribution and signal transmission.
Abstract
Description
Display devices, electronic equipment
[0001] One embodiment of the present invention relates to a display device, an electronic device, or a semiconductor device.
[0002] Note that one embodiment of the present invention is not limited to the above technical field. The technical field of one embodiment of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. Alternatively, one embodiment of the present invention relates to a process, a machine, manufacture, or a composition of matter. Therefore, more specifically, examples of the technical field of one embodiment of the present invention disclosed in this specification include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, a driving method thereof, or a manufacturing method thereof.
[0003] A display in which the chromaticity of micro light-emitting diodes changes little with respect to current density is known (see Patent Document 1). Specifically, each of a plurality of pixels includes a display element and a microcontroller. The microcontroller includes a first transistor, a triangular wave generating circuit, a comparator, a switch, and a constant current circuit. The first transistor has a function of maintaining a potential corresponding to data written to the pixel when turned off. The triangular wave generating circuit has a function of generating a triangular wave signal. The comparator has a function of generating an output signal corresponding to the maintained potential and the triangular wave signal. The switch has a function of controlling whether or not a current flowing through the constant current circuit is passed to the display element according to the output signal.
[0004] International Publication No. WO2019 / 130138 Pamphlet
[0005] An object of one embodiment of the present invention is to provide a novel display device with excellent convenience, usefulness, or reliability, or a novel electronic device with excellent convenience, usefulness, or reliability, or a novel display device, a novel electronic device, or a novel semiconductor device.
[0006] Note that the description of these problems does not preclude the existence of other problems. Note that one embodiment of the present invention does not necessarily solve all of these problems. Note that problems other than these will become apparent from the description of the specification, drawings, claims, etc., and it is possible to extract other problems from the description of the specification, drawings, claims, etc.
[0007] (1) One embodiment of the present invention is a display device including a first set of pixels, a second set of pixels, a third set of pixels, a first conductive film, and a second conductive film.
[0008] The first set of pixels includes a first set of light emitting devices, a first pad, a second pad, a conductive material, and a first set of pixel circuits.
[0009] The first set of light emitting devices are electrically connected to the first pads, the first pads overlapping the second pads, a conductive material is sandwiched between the first pads and the second pads, the conductive material electrically connecting the first pads and the second pads, and the second pads are electrically connected to the first set of pixel circuits.
[0010] The first set of pixel circuits includes a first group of pixel circuits, and the first group of pixel circuits includes a first pixel circuit.
[0011] The second set of pixels comprises a second set of light-emitting devices and a second set of pixel circuits, the second set of light-emitting devices are electrically connected to the second set of pixel circuits, the second set of pixel circuits includes a second group of pixel circuits, and the second group of pixel circuits includes a second pixel circuit.
[0012] The third set of pixels includes a third set of light emitting devices and a third set of pixel circuits, the third set of light emitting devices being electrically connected to the third set of pixel circuits.
[0013] The first conductive film is electrically connected to the first group of pixel circuits and the second group of pixel circuits.
[0014] The second conductive film is electrically connected to the first pixel circuit and the second pixel circuit.
[0015] This allows, for example, using the first conductive film, a signal to be supplied to one or more pixel circuits included in a first set of pixel circuits during a first period, and also allows a signal to be supplied to one or more pixel circuits included in a second set of pixel circuits during the same first period, and also allows, for example, using the first conductive film, a signal to be supplied to multiple pixel circuits during the first period.
[0016] Furthermore, for example, a signal can be supplied to a first pixel circuit included in a first set of pixel circuits using a second conductive film during a second period. Also, a signal can be supplied to a second pixel circuit included in a second set of pixel circuits during the same second period. Also, during the second period, the first pixel circuit can supply power to a second pad of the first set of pixels, and the second pixel circuit can supply power to a second pad of the second set of pixels.
[0017] Furthermore, the area of the second pad can be made closer to the area occupied by the first set of pixel circuits. Furthermore, the area of the first pad can be made closer to the area occupied by the first set of pixel circuits. Furthermore, electrical connection between the second pad and the first pad is facilitated. Furthermore, electrical connection between the first set of pixel circuits and the first set of light-emitting devices is facilitated. Alternatively, bonding between the first set of pixel circuits and the first set of light-emitting devices is facilitated. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0018] (2) Another embodiment of the present invention is a display device including a first set of pixels, a second set of pixels, a third set of pixels, a first conductive film, and a third conductive film.
[0019] The first set of pixels includes a first set of light emitting devices, a first pad, a second pad, a conductive material, and a first set of pixel circuits.
[0020] The first set of light emitting devices are electrically connected to the first pads, the first pads overlapping the second pads, a conductive material is sandwiched between the first pads and the second pads, the conductive material electrically connecting the first pads and the second pads, and the second pads are electrically connected to the first set of pixel circuits.
[0021] The first set of pixel circuits includes a first group of pixel circuits, and the first group of pixel circuits includes a first pixel circuit.
[0022] The second set of pixels comprises a second set of light-emitting devices and a second set of pixel circuits, the second set of light-emitting devices are electrically connected to the second set of pixel circuits, the second set of pixel circuits includes a second group of pixel circuits, and the second group of pixel circuits includes a second pixel circuit.
[0023] The third set of pixels comprises a third set of light-emitting devices and a third set of pixel circuits, the third set of light-emitting devices are electrically connected to the third set of pixel circuits, the third set of pixel circuits includes a third group of pixel circuits, and the third group of pixel circuits includes the third pixel circuit.
[0024] The first conductive film is electrically connected to the first group of pixel circuits and the second group of pixel circuits.
[0025] The third conductive film is electrically connected to the first pixel circuit and the third pixel circuit.
[0026] This allows, for example, a signal to be supplied to one or more pixel circuits included in the first set of pixel circuits and the third set of pixel circuits during a first period, and also allows, for example, a signal to be supplied to one or more pixel circuits included in the third set of pixel circuits during a period different from the first period.
[0027] Furthermore, for example, during the second period, a signal can be supplied to a first pixel circuit included in a first set of pixel circuits. Furthermore, during the same second period, a signal can be supplied to a third pixel circuit included in a third set of pixel circuits. Furthermore, during the second period, the first pixel circuit can supply power to the second pad of the first set of pixels, and the third pixel circuit can supply power to the second pad of the third set of pixels. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0028] (3) Another embodiment of the present invention is a display device including a first set of pixels, a second set of pixels, a third set of pixels, a first conductive film, a fourth conductive film, and a fifth conductive film.
[0029] The first set of pixels includes a first set of light emitting devices, a first pad, a second pad, a conductive material, and a first set of pixel circuits.
[0030] The first set of light emitting devices are electrically connected to the first pads, the first pads overlapping the second pads, a conductive material is sandwiched between the first pads and the second pads, the conductive material electrically connecting the first pads and the second pads, and the second pads are electrically connected to the first set of pixel circuits.
[0031] The first set of pixel circuits includes a first group of pixel circuits, and the first group of pixel circuits includes a first pixel circuit.
[0032] The second set of pixels comprises a second set of light-emitting devices and a second set of pixel circuits, the second set of light-emitting devices are electrically connected to the second set of pixel circuits, the second set of pixel circuits includes a second group of pixel circuits, and the second group of pixel circuits includes a second pixel circuit.
[0033] The third set of pixels comprises a third set of light-emitting devices and a third set of pixel circuits, the third set of light-emitting devices are electrically connected to the third set of pixel circuits, the third set of pixel circuits includes a third group of pixel circuits, and the third group of pixel circuits includes the third pixel circuit.
[0034] The first conductive film is electrically connected to the first group of pixel circuits and the second group of pixel circuits.
[0035] The fourth conductive film is electrically connected to the first pixel circuit and the second pixel circuit.
[0036] The fifth conductive film is electrically connected to the first pixel circuit and the third pixel circuit.
[0037] This allows, for example, using the first conductive film, a signal to be supplied to one or more pixel circuits included in a first set of pixel circuits during a first period, and also allows a signal to be supplied to one or more pixel circuits included in a second set of pixel circuits during the same first period, and also allows, for example, using the first conductive film, a signal to be supplied to multiple pixel circuits during the first period.
[0038] Furthermore, for example, a signal can be supplied to a first pixel circuit included in a first set of pixel circuits during the second period using the fourth conductive film and the fifth conductive film.
[0039] Furthermore, by using two conductive films that intersect with each other, for example, the fourth conductive film and the fifth conductive film, it is possible to select one pixel circuit from the first set and supply a signal to it. Also, the number of conductive films for supplying signals can be reduced. As a result, it is possible to provide a novel display device that is excellent in convenience, usability, and reliability.
[0040] (4) Another embodiment of the present invention is the above display device including the sixth conductive film.
[0041] The first set of light emitting devices includes a first light emitting device, the second set of light emitting devices includes a second light emitting device, and the sixth conductive film is electrically connected to the first light emitting device and the second light emitting device.
[0042] This allows, for example, using the sixth conductive film, to select a second light-emitting device included in the second set of light-emitting devices at the same time as selecting a first light-emitting device included in the first set of light-emitting devices, and allows the first pads of the first set of pixels to supply power to the second light-emitting device at the same time as supplying power to the first light-emitting device.
[0043] Furthermore, the area of the first pad can be made closer to the area occupied by the first set of light-emitting devices. Furthermore, electrical connection between the second pad and the first pad is facilitated. Furthermore, electrical connection between the first set of pixel circuits and the first set of light-emitting devices is facilitated. Alternatively, bonding between the first set of pixel circuits and the first set of light-emitting devices is facilitated. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0044] (5) Another embodiment of the present invention is the above display device including a seventh conductive film.
[0045] The first set of light emitting devices includes a first light emitting device, the third set of light emitting devices includes a third light emitting device, and the seventh conductive film is electrically connected to the first light emitting device and the third light emitting device.
[0046] (6) Another embodiment of the present invention is the above display device, in which the first light-emitting device is a light-emitting diode.
[0047] As a result, for example, by using the seventh conductive film, a third light-emitting device included in a third set of light-emitting devices can be selected at the same time as a first light-emitting device included in a first set of light-emitting devices is selected. Also, a pad of a third set of pixels can supply power to a third light-emitting device at the same time as a first pad of a first set of pixels supplies power to a first light-emitting device. As a result, a novel display device excellent in convenience, usability, and reliability can be provided.
[0048] (7) Another embodiment of the present invention is the above display device including an eighth conductive film and a ninth conductive film.
[0049] The first pixel circuit includes a first switch, a second switch, a transistor, a capacitor, and a node.
[0050] The first switch has a first terminal electrically connected to the eighth conductive film, a second terminal electrically connected to the node, and a function of controlling a conductive state or a non-conductive state based on the potential of the first conductive film.
[0051] The transistor includes a gate electrode electrically connected to the node and a first electrode electrically connected to the ninth conductive film.
[0052] The capacitor includes a conductive film electrically connected to the node and a conductive film electrically connected to the ninth conductive film.
[0053] The second switch has a first terminal electrically connected to the second electrode of the transistor, a second terminal electrically connected to the second pad, and a function of controlling a conductive state or a non-conductive state based on a second selection signal.
[0054] (8) Another embodiment of the present invention is the above-described display device including the first driver circuit.
[0055] The first driver circuit supplies a first selection signal to the first conductive film, and the second driver circuit supplies a second selection signal to the second conductive film.
[0056] The first driving circuit controls the potential of the sixth conductive film.
[0057] (9) Another embodiment of the present invention is the display device described above, including a first functional layer and a second functional layer.
[0058] The first functional layer includes a first set of pixel circuits and a second pad.
[0059] The second functional layer overlies the first functional layer, and the second functional layer includes a first set of light emitting devices and a first pad.
[0060] This allows the first set of pixel circuits to be electrically connected to the first set of light-emitting devices using the second pad, the first pad, and the conductive material. Furthermore, for example, multiple pixel circuits and multiple light-emitting devices can be connected using a single pad. Specifically, three pixel circuits can be connected to three light-emitting devices using a single pad. Furthermore, the number of connection points can be reduced, thereby preventing connection failures. Furthermore, the area required for connection can be reduced relative to the area occupied by the first set of light-emitting devices. As a result, a novel display device with excellent convenience, usefulness, and reliability can be provided.
[0061] (10) Another embodiment of the present invention is the above display device, which includes a third functional layer.
[0062] The third functional layer has a region that sandwiches the first functional layer between itself and the second functional layer, and the third functional layer includes a second drive circuit.
[0063] The second driver circuit has a function of supplying an image signal.
[0064] This allows the generation of image signals to be displayed on the display device without increasing the external size of the display device. Furthermore, the second drive circuit and the first set of pixel circuits disposed directly above it can be electrically connected. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0065] (11) Another embodiment of the present invention is an electronic device including a computing unit and the above-described display device.
[0066] The computing unit generates image information, and the display device displays the image information.
[0067] (12) Another embodiment of the present invention is an electronic device including the above display device and a computing unit.
[0068] The third functional layer includes a computing unit that generates image information, and a display device that displays the image information.
[0069] In the drawings accompanying this specification, components are classified by function and shown as independent blocks in block diagrams, but in reality, it is difficult to completely separate components by function, and one component may be involved in multiple functions.
[0070] In this specification, the names of the source and drain of a transistor are interchangeable depending on the polarity of the transistor and the level of the potential applied to each terminal. Generally, in an n-channel transistor, a terminal to which a low potential is applied is called a source, and a terminal to which a high potential is applied is called a drain. In a p-channel transistor, a terminal to which a low potential is applied is called a drain, and a terminal to which a high potential is applied is called a source. In this specification, for convenience, the connection relationship of a transistor may be described assuming that the source and drain are fixed, but in reality, the names of the source and drain are interchangeable depending on the above-mentioned potential relationship.
[0071] In this specification, the source of a transistor refers to a source region that is part of a semiconductor film that functions as an active layer, or a source electrode connected to the semiconductor film. Similarly, the drain of a transistor refers to a drain region that is part of the semiconductor film, or a drain electrode connected to the semiconductor film. Furthermore, the gate refers to a gate electrode.
[0072] In this specification, a state in which transistors are connected in series means, for example, a state in which only one of the source or drain of a first transistor is connected to only one of the source or drain of a second transistor, and a state in which transistors are connected in parallel means a state in which one of the source or drain of a first transistor is connected to one of the source or drain of a second transistor, and the other of the source or drain of the first transistor is connected to the other of the source or drain of the second transistor.
[0073] In this specification, "connection" means an electrical connection, and corresponds to a state in which a current, voltage, or potential can be supplied or transmitted. Therefore, a connected state does not necessarily refer to a direct connection, but also includes a state in which a current, voltage, or potential can be supplied or transmitted via a circuit element such as a wiring, resistor, diode, or transistor.
[0074] In this specification, even when components that appear independent on a circuit diagram are connected to each other, in reality, one conductive film may have the functions of multiple components, for example, when part of a wiring functions as an electrode. In this specification, the term "connection" also includes such cases where one conductive film has the functions of multiple components.
[0075] In this specification, one of a first electrode and a second electrode of a transistor refers to a source electrode, and the other refers to a drain electrode.
[0076] According to one embodiment of the present invention, a novel display device with excellent convenience, usefulness, or reliability can be provided. Alternatively, a novel electronic device with excellent convenience, usefulness, or reliability can be provided. Alternatively, a novel display device, a novel electronic device, or a novel semiconductor device can be provided.
[0077] Note that the description of these effects does not preclude the existence of other effects. Note that one embodiment of the present invention does not necessarily have all of these effects. Note that effects other than these will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract other effects from the description in the specification, drawings, claims, etc.
[0078] FIGS. 1A and 1B are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 2 is a block diagram illustrating a configuration of a display device according to an embodiment. FIG. 3 is a block diagram illustrating a configuration of a display device according to an embodiment. FIG. 4 is a circuit diagram illustrating a configuration of a display device according to an embodiment. FIG. 5 is a timing chart illustrating a method for driving a display device according to an embodiment. FIG. 6 is a circuit diagram illustrating a configuration of a display device according to an embodiment. FIG. 7 is a diagram illustrating a configuration of a display device according to an embodiment. FIGS. 8A and 8B are block diagrams illustrating a configuration of a display device according to an embodiment. FIGS. 9A and 9B are block diagrams illustrating a configuration of a display device according to an embodiment. FIGS. 10A and 10B are diagrams illustrating a configuration of a display device according to an embodiment. FIGS. 11A and 11B are diagrams illustrating a configuration of a display device according to an embodiment. FIGS. 12A and 12B are diagrams illustrating a configuration of a display device according to an embodiment. FIGS. 13A and 13B are diagrams illustrating a configuration of a display device according to an embodiment. FIGS. 14A and 14B are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 15 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 16 is a diagram illustrating a configuration of a display device according to an embodiment. FIGS. 17A and 17B are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 18 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 19 is a diagram illustrating a configuration of a display device according to an embodiment. FIGS. 20A and 20B are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 21 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 22 is a diagram illustrating a configuration of a display device according to an embodiment. FIGS. 23A and 23B are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 24 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 25 is a diagram illustrating a configuration of a display device according to an embodiment. FIGS. 26A and 26B are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 27 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 28 is a diagram illustrating a configuration of a display device according to an embodiment.FIG. 29 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 30 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 31 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 32 is a diagram illustrating a configuration of a display device according to an embodiment. FIGS. 33A and 33B are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 34 is a diagram illustrating a configuration of a display device according to an embodiment. FIGS. 35A and 35B are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 36 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 37 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 38 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 39 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 40 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 41 is a diagram illustrating a configuration of a display device according to an embodiment. FIGS. 42A to 42C are diagrams illustrating a configuration of a transistor according to an embodiment. FIGS. 43A to 43C are diagrams illustrating a metal oxide according to an embodiment. FIGS. 44A to 44D are diagrams illustrating an electronic device according to an embodiment. FIGS. 45A and 45B are diagrams illustrating an electronic device according to an embodiment.
[0079] A display device according to one embodiment of the present invention includes a first set of pixels, a second set of pixels, a first conductive film, and a second conductive film. The first set of pixels includes a first set of light-emitting devices, a first pad, a second pad, a conductive material, and a first set of pixel circuits. The first set of light-emitting devices are electrically connected to the first pads, and the first pads overlap the second pads. The conductive material is sandwiched between the first pad and the second pad, and the conductive material electrically connects the first pad and the second pad. The second pad is electrically connected to the first set of pixel circuits. The first set of pixel circuits includes a first group of pixel circuits, and the first group of pixel circuits includes the first pixel circuit. The second set of pixels includes a second set of light-emitting devices and a second set of pixel circuits, the second set of light-emitting devices are electrically connected to the second set of pixel circuits, the second set of pixel circuits includes a second group of pixel circuits, the second group of pixel circuits includes a second pixel circuit. The first conductive film is electrically connected to the first group of pixel circuits and the second group of pixel circuits. The second conductive film is electrically connected to the first pixel circuits and the second pixel circuits.
[0080] This allows, for example, using the first conductive film, a signal to be supplied to one or more pixel circuits included in a first set of pixel circuits during a first period, and also allows a signal to be supplied to one or more pixel circuits included in a second set of pixel circuits during the same first period, and also allows, for example, using the first conductive film, a signal to be supplied to multiple pixel circuits during the first period.
[0081] Furthermore, for example, a signal can be supplied to a first pixel circuit included in a first set of pixel circuits using a second conductive film during a second period. Also, a signal can be supplied to a second pixel circuit included in a second set of pixel circuits during the same second period. Also, during the second period, the first pixel circuit can supply power to a second pad of the first set of pixels, and the second pixel circuit can supply power to a second pad of the second set of pixels.
[0082] Furthermore, the area of the second pad can be made closer to the area occupied by the first set of pixel circuits. Furthermore, the area of the first pad can be made closer to the area occupied by the first set of pixel circuits. Furthermore, electrical connection between the second pad and the first pad is facilitated. Furthermore, electrical connection between the first set of pixel circuits and the first set of light-emitting devices is facilitated. Alternatively, bonding between the first set of pixel circuits and the first set of light-emitting devices is facilitated. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0083] 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 in form and details can be made 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. In the configuration of the invention described below, the same parts or parts having similar functions will be denoted by the same reference numerals in different drawings, and repeated explanations will be omitted.
[0084] Embodiment 1 In this embodiment, a structure of a display device according to one embodiment of the present invention will be described with reference to FIGS.
[0085] FIG. 1A is a top view illustrating a structure of a display device of one embodiment of the present invention, and FIG. 1B is a cross-sectional view of the display device of one embodiment of the present invention taken along the cutting line X1-X2 illustrated in FIG. 1A.
[0086] FIG. 2 is a block diagram illustrating the configuration of a set of pixels 703(i,j) shown in FIG. 1A.
[0087] FIG. 3 is a block diagram illustrating the configuration of a set of pixels 703(i,j) shown in FIG.
[0088] FIG. 4 is a circuit diagram illustrating the configuration of a pair of pixels 703(i,j) shown in FIG.
[0089] FIG. 5 is a timing chart illustrating the operation of the pair of pixels 703(i,j) shown in FIG.
[0090] FIG. 6 is a circuit diagram illustrating the configuration of a pair of pixels 703(i, j) different from that in FIG.
[0091] FIG. 7 is a top view illustrating a structure of a display device according to one embodiment of the present invention.
[0092] 8A is a block diagram illustrating the configuration of a set of pixels 703(i,j) shown in FIG. 7, and FIG. 8B is a block diagram illustrating a configuration different from the set of pixels 703(i,j) shown in FIG. 8A.
[0093] 9A is a block diagram illustrating the configuration of a set of pixels 703(i,j) shown in FIG. 8, and FIG. 9B is a block diagram illustrating a configuration different from the set of pixels 703(i,j) shown in FIG. 9A.
[0094] In this specification, variables that take on integer values of 1 or greater may be used as symbols. For example, (p) including a variable p that takes on an integer value of 1 or greater may be used as part of a symbol specifying any one of up to p components. Also, for example, (m, n) including variables m and n that take on integer values of 1 or greater may be used as part of a symbol specifying any one of up to m×n components.
[0095] <Configuration Example 1 of Display Device> A display device 700 of one embodiment of the present invention includes a pair of pixels 703(i, j), a functional layer 520(1), and a functional layer 520(2) (see FIGS. 1A and 1B ). For example, the functional layer 520(1) and the functional layer 520(2) can be formed and then bonded to each other to form the display device of one embodiment of the present invention.
[0096] <<Configuration Example of a Set of Pixels 703(i,j)>> A set of pixels 703(i,j) includes a set of light-emitting devices 550(i,j), a set of pixel circuits 530(i,j), pads 541(i,j), pads 542(i,j), and conductive materials 543(i,j) (see FIGS. 1B and 3). For example, a set of light-emitting devices 550(i,j) includes light-emitting devices 550(i,j)(p,1) to 550(i,j)(p,t) (see FIGS. 2 and 3). Specifically, a light-emitting device that emits red light, a light-emitting device that emits green light, and a light-emitting device that emits blue light can be used in one set of light-emitting devices. A set of pixel circuits 530(i,j) includes pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) (see FIGS. 2 and 3). Note that t is not limited to 3 and is an integer of 1 or greater. For example, a metal or a composite material can be used for the conductive material 543. Specifically, nickel particles or nickel particles coated with gold can be used for the conductive material 543. A composite material in which resin is plated with metal can be used for the conductive material 543. A composite material in which metal or metal-plated resin is further coated with an insulating material can be used for the conductive material 543.
[0097] <<Configuration Example of Functional Layer 520(1)>> The functional layer 520(1) includes a set of pixel circuits 530(i,j) and a pad 541(i,j). The pad 541(i,j) is electrically connected to the set of pixel circuits 530(i,j).
[0098] <<Configuration Example of Functional Layer 520(2)>> The functional layer 520(2) overlaps the functional layer 520(1) and includes a set of light-emitting devices 550(i,j) and pads 542(i,j). The pads 542(i,j) are electrically connected to the set of light-emitting devices 550(i,j). For example, the functional layer 520(2) includes a matrix of multiple light-emitting devices. Note that a light-emitting device that emits red light, a light-emitting device that emits green light, and a light-emitting device that emits blue light may be used in the functional layer 520(2). Alternatively, for example, multiple light-emitting devices that emit blue light may be arranged in a matrix, with a color conversion layer that converts the blue light into light of another color disposed directly above them. Alternatively, LEDs, OLEDs, etc. may be used as the light-emitting devices.
[0099] <<Configuration Example of Conductive Material 543(i,j)>> The conductive material 543(i,j) is sandwiched between the pad 541(i,j) and the pad 542(i,j) and electrically connects the pad 541(i,j) and the pad 542(i,j). In other words, the conductive material 543(i,j) electrically connects a set of pixel circuits 530(i,j) and a set of light-emitting devices 550(i,j) via the pad 541(i,j) and the pad 542(i,j).
[0100] As a result, a set of pixel circuits 530(i,j) can be electrically connected to a set of light-emitting devices 550(i,j) using the pads 541(i,j), 542(i,j), and the conductive material 543(i,j). Furthermore, for example, q pixel circuits can be connected to q light-emitting devices using q or fewer pads, where q is an integer greater than or equal to 1. Specifically, three pixel circuits can be connected to three light-emitting devices using a pair of pads. Furthermore, the number of connection points can be reduced, thereby preventing connection failures. Furthermore, the area required for connection can be reduced relative to the area occupied by a set of light-emitting devices 550(i,j). In other words, in one aspect of the present invention, a configuration in which multiple actively driven pixel circuits are connected to multiple light-emitting devices using a pair of pads makes it possible to drive the multiple light-emitting devices in a manner similar to passive driving. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0101] <Structure Example 2 of Display Device> A display device of one embodiment of the present invention includes a conductive film COM1 and a conductive film COM2(i)(p, q) (see FIG. 3). Note that the conductive film COM1 and the conductive film COM2(i)(p, q) both function as wirings.
[0102] A set of pixel circuits 530(i,j) includes pixel circuits 530(i,j)(p,q) and 530(i,j)(p,2), and a set of light-emitting devices 550(i,j) includes light-emitting devices 550(i,j)(p,q) and 550(i,j)(p,2). Furthermore, a set of pixels 703(i,j) includes pixel 702(i,j)(p,q) (see FIG. 2). For example, a set of pixel circuits 530(i,j) includes t pixel circuits, where t is an integer equal to or greater than 1, and p is an integer equal to or greater than 1 and equal to or less than t.
[0103] <<Configuration Example of Pixel 702(i,j)(p,q)>> The pixel 702(i,j)(p,q) includes a pixel circuit 530(i,j)(p,q) and a light-emitting device 550(i,j)(p,q).
[0104] The pixel circuit 530(i,j)(p,q) is electrically connected to the conductive film COM1, and the pixel circuit 530(i,j)(p,q) is electrically connected to one electrode of the light-emitting device 550(i,j)(p,q) for a predetermined period. For example, when a set of pixels 703(i,j) includes pixels 702(i,j)(p,1) to 702(i,j)(p,t), the period during which the set of pixels 703(i,j) perform display can be divided into t equal parts to define the predetermined period.
[0105] The other electrode of the light-emitting device 550(i,j)(p,q) is electrically connected to the conductive film COM2(i)(p,q), and a predetermined voltage is supplied between the conductive film COM2(i)(p,q) and the conductive film COM1 during the predetermined period. For example, a voltage that drives the light-emitting device 550(i,j)(p,q) at maximum brightness can be used as the predetermined voltage. Note that the pixel circuit 530(i,j)(p,q) controls the voltage distributed to the light-emitting device 550(i,j)(p,q) from the predetermined voltage. Furthermore, during periods other than the predetermined period, a voltage that does not cause the light-emitting device 550(i,j)(p,q) to emit light is supplied to the conductive film COM2(i)(p,q).
[0106] This allows, for example, a light-emitting device 550(i,j)(p,q) to be selected and driven using a pixel circuit 530(i,j)(p,q). Furthermore, a pixel circuit 530(i,j)(p,q) can be selected and driven for a predetermined period. Furthermore, a set of pixels 703(i,j) can be driven over multiple periods. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0107] <Configuration Example 3 of Display Device> A display device of one embodiment of the present invention includes a conductive film S1(j)q, a conductive film G1(i)p, and a conductive film G2(i)(p,q) (see FIG. 4). Note that the conductive films S1(j)q, S1(j)q-1, G1(i)p, and G2(i)(p,q) all function as wirings.
[0108] <<Configuration Example of Pixel Circuit 530(i,j)(p,q)>> The pixel circuit 530(i,j)(p,q) includes a switch SW2(p,q), a switch SW11, a transistor M11, a capacitor C11, and a node N11.
[0109] The switch SW11 has a first terminal electrically connected to the conductive film S1(j)q, a second terminal electrically connected to the node N11, and a function of controlling the conductive state or non-conductive state based on the potential of the conductive film G1(i)p.
[0110] The transistor M11 includes a gate electrode electrically connected to the node N11 and a first electrode electrically connected to the conductive film COM1.
[0111] The capacitor C11 includes a conductive film electrically connected to the node N11 and a conductive film electrically connected to the conductive film COM1.
[0112] The switch SW2(p, q) has a first terminal electrically connected to the second electrode of the transistor M11, a second terminal electrically connected to the pad 541(i, j), and a function of controlling the conductive state or non-conductive state based on the potential of the conductive film G2(i)(p, q).
[0113] Furthermore, a set of pixel circuits 530(i,j) includes pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t), and is electrically connected to a pad 541(i,j) via any one of switches SW2(p,1) to SW2(p,t). The switches SW2(p,1) to SW2(p,t) have the function of selecting any one of the pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) and establishing electrical continuity between the pixel circuit 530(i,j) and the pad 541(i,j). The switches SW2(p,1) to SW2(p,t) include a switch SW2(p,q+1).
[0114] Note that the illustrated circuit is an example of a circuit that can be used for the pixel circuit 530(i,j)(p,q), and the configuration is not limited to this. For example, the circuit shown in FIG. 6 can be used as part of the pixel circuit 530(i,j)(p,q). Specifically, a switch SW12, a switch SW13, and a capacitor C12 can be used for the pixel circuit 530(i,j)(p,q). The display device also includes conductive films G12(i)p and G13(i)p electrically connected to the pixel circuit 530(i,j)(p,q). The switch SW12 has a first terminal electrically connected to the node N11, a second terminal electrically connected to the first electrode of the transistor M11, and a function of controlling the conductive state or non-conductive state based on the potential of the conductive film G12(i)p. The switch SW13 has a first terminal electrically connected to the node N11, a second terminal electrically connected to the conductive film COM1, and a function of controlling the conductive state or non-conductive state based on the potential of the conductive film G13(i)p. The capacitor C12 has a conductive film connected to the second terminal of the switch SW11 and a conductive film electrically connected to the node N11.
[0115] <Structure Example 4 of Display Device> A display device of one embodiment of the present invention includes a driver circuit GD (see FIG. 1B).
[0116] <<Configuration Example of Driver Circuit GD>> The driver circuit GD supplies a first selection signal to the conductive film G1(i)p. The pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) electrically connected to the conductive film G1(i)p can acquire, for example, an image signal from any one of the conductive films S1(j)1 to S1(j)t based on the first selection signal (see FIG. 3 ).
[0117] The driver circuit GD also supplies a second selection signal to the conductive film G2(i)(p,q). The pixel circuit 530(i,j)(p,q) electrically connected to the conductive film G2(i)(p,q) becomes conductive with the pad 541(i,j) based on the second selection signal. The driver circuit GD selects one of the conductive films G2(i)(p,1) to G2(i)(p,t) in a predetermined order and supplies the second selection signal for a predetermined period.
[0118] The drive circuit GD controls the potential of the conductive film COM2(i)(p,q). During the period when the second selection signal is supplied to the conductive film G2(i)(p,q), the drive circuit GD controls the potential of the conductive film COM2(i)(p,q) so as to apply a predetermined voltage between the conductive film COM2(i)(p,q) and the conductive film COM1. For example, the drive circuit GD controls the potential of the conductive film COM2(i)(p,q) so as to apply a voltage that drives the light-emitting device 550(i,j)(p,q) at maximum brightness. The drive circuit GD selects one of the conductive films COM2(i)(p,1) through COM2(i)(p,t) in a predetermined order and controls the potential so as to apply the predetermined voltage for a predetermined period. Furthermore, the potentials of the conductive films COM2(i)(p,1) through COM2(i)(p,t) are controlled to a potential that does not cause the light-emitting device to emit light during periods other than the predetermined period.
[0119] <Configuration Example 5 of Display Device> A display device of one embodiment of the present invention includes pads 541(i)(p, q), pads 542(i)(p, q), and conductive materials 543(i)(p, q) (see FIG. 1B ).
[0120] The pads 541(i)(p,q) are electrically connected to, for example, the drive circuit GD, and the pads 542(i)(p,q) are electrically connected to, for example, the conductive film COM2(i)(p,q). Furthermore, the conductive material 543(i)(p,q) is sandwiched between the pads 541(i)(p,q) and 542(i)(p,q) and electrically connects the pads 541(i)(p,q) and 542(i)(p,q).
[0121] This allows the potential of the conductive film COM2(i)(p, q) to be controlled using the drive circuit GD.
[0122] <<Example 1 of Driving Method of Display Device>> A method for driving a display device of one embodiment of the present invention will be described. Specifically, the method for driving the display device will be described using operations of pixels 702(i,j)(p,q−1), 702(i,j)(p,q), and 702(i,j)(p,q+1) included in a set of pixels 703(i,j) (see FIGS. 4 and 5 ).
[0123] [First Step] In the period from time t10 to time t11, a first selection signal is supplied to the conductive film G1(i)p (see FIG. 5).
[0124] The pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) included in one set of pixel circuits 530(i,j) acquire image signals based on a first selection signal.
[0125] For example, the pixel circuit 530(i,j)(p,q) acquires an image signal from the conductive film S1(j)q.
[0126] [Second Step] During the period from time t11 to time t18, one of the conductive films G2(i)(p,1) to G2(i)(p,t) is selected in a predetermined order and a second selection signal is supplied to the selected conductive film. Also, one of the conductive films COM2(i)(p,1) to COM2(i)(p,t) is selected in a predetermined order and a predetermined potential is supplied to the selected conductive film. Note that the conductive films G2(i)(p,1) to G2(i)(p,t) include the conductive film G2(i)(p+1,1).
[0127] The pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) included in one set of pixel circuits 530(i,j) control the potential of the pad 541(i,j) based on the acquired image signal and the second selection signal.
[0128] [Operation of pixel 702(i,j)(p,q−1) in the second step] For example, during the period from time t14 to time t15, the pixel circuit 530(i,j)(p,q−1) is supplied with a second selection signal from the conductive film G2(i)(p,q−1), and controls the potential of the pad 541(i,j) based on the acquired image signal.
[0129] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p, q-1) during the period from time t14 to time t15.
[0130] As a result, the light-emitting device 550(i,j)(p,q-1) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p,q-1) during the period from time t14 to time t15.
[0131] [Operation of pixel 702(i,j)(p,q) in the second step] For example, pixel circuit 530(i,j)(p,q) receives a selection signal from conductive film G2(i)(p,q) from time t15 to time t16 and controls the potential of pad 541(i,j) based on the acquired image signal. Furthermore, conductive film COM2(i)(p,q) receives a predetermined potential from time t15 to time t16. As a result, light-emitting device 550(i,j)(p,q) displays an image at a predetermined brightness based on the potential difference between pad 541(i,j) and conductive film COM2(i)(p,q) from time t15 to time t16.
[0132] [Operation of pixel 702(i,j)(p,q+1) in the second step] For example, pixel circuit 530(i,j)(p+1) receives a selection signal from conductive film G2(i)(p,q+1) from time t16 to time t17 and controls the potential of pad 541(i,j) based on the acquired image signal. Furthermore, conductive film COM2(i)(p,q+1) receives a predetermined potential from time t16 to time t17. As a result, light-emitting device 550(i,j)(p,q+1) displays an image at a predetermined brightness based on the potential difference between pad 541(i,j) and conductive film COM2(i)(p,q+1) from time t16 to time t17.
[0133] [Third Step] During the period from time t18 to time t20, a potential that turns off the switches SW2(p,1) to SW2(p,t) is supplied to the conductive films G2(i)(p,1) to G2(i)(p,t). Also, a potential that turns off the light-emitting devices 550(i,j)(p,1) to 550(i,j)(p,t) is supplied to the conductive films COM2(i)(p,1) to COM2(i)(p,t).
[0134] Note that a period FR1 in the drawing corresponds to one frame period. In this way, the display device of one embodiment of the present invention can be duty-driven.
[0135] <<Driving Method Example 2 of Display Device>> The display device of one embodiment of the present invention can be driven by a method different from Driving Method 1. Driving Method Example 2 differs from Driving Method 1 in that display is divided into multiple times during one frame period from time t30 to time t40. Here, differences will be described in detail, and the above description will be used for parts having the same configuration.
[0136] [First Step] In the period from time t30 to time t31, a first selection signal is supplied to the conductive film G1(i)p (see FIG. 5).
[0137] The pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) included in one set of pixel circuits 530(i,j) acquire image signals based on a first selection signal.
[0138] [Second Step] During the period from time t31 to time t35, one of the conductive films G2(i)(p,1) to G2(i)(p,t) is selected in a predetermined order and a second selection signal is supplied to the selected conductive film. Also, one of the conductive films COM2(i)(p,1) to COM2(i)(p,t) is selected in a predetermined order and a predetermined potential is supplied to the selected conductive film.
[0139] The pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) included in one set of pixel circuits 530(i,j) control the potential of the pad 541(i,j) based on the acquired image signal and the second selection signal.
[0140] [Third Step] During the period from time t36 to time t40, one of the conductive films G2(i)(p,1) to G2(i)(p,t) is selected in a predetermined order and a second selection signal is supplied to it. Also, one of the conductive films COM2(i)(p,1) to COM2(i)(p,t) is selected in a predetermined order and a predetermined potential is supplied to it.
[0141] The pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) included in one set of pixel circuits 530(i,j) control the potential of the pad 541(i,j) based on the acquired image signal and the second selection signal.
[0142] Note that the period FR2 in the figure corresponds to one frame period. This allows each pixel of the display device of one embodiment of the present invention to display twice in one frame period. Furthermore, for example, the occurrence of color breaking can be suppressed.
[0143] <Structure Example 5 of Display Device> A display device of one embodiment of the present invention includes a functional layer 520(3) (see FIG. 1B).
[0144] The functional layer 520(3) has a region sandwiching the functional layer 520(1) between itself and the functional layer 520(2). In other words, the functional layer 520(3), the functional layer 520(1), and the functional layer 520(2) are stacked.
[0145] The functional layer 520(3) includes a driver circuit SD, which supplies image signals to the conductive film S1(j)q. The functional layer 520(3) also includes a terminal 519B.
[0146] This allows the generation of image signals to be displayed on the display device without increasing the external size of the display device. Furthermore, the driver circuit SD and a set of pixel circuits 530(i, j) arranged directly above it can be electrically connected. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0147] <Configuration Example 6 of Display Device> A display device of one embodiment of the present invention includes a region 231 (see FIG. 7 ). The region 231 includes a group of pixels 703(i,1) to 703(i,n) and another group of pixels 703(1,j) to 703(m,j). In other words, the region 231 includes a group of pixel circuits 530(i,1) to 530(i,n) and another group of pixel circuits 530(1,j) to 530(m,j). Note that m is an integer of 1 or more, and i is an integer of 1 to m, inclusive. Furthermore, n is an integer of 1 or more, and j is an integer of 1 to n, inclusive.
[0148] A group of pixel circuits 530(i,1) to 530(i,n) are arranged in the row direction (the direction indicated by the arrow R1 in the figure), and a group of pixel circuits 530(i,1) to 530(i,n) includes a set of pixel circuits 530(i,j), and a group of pixel circuits 530(i,1) to 530(i,n) are electrically connected to a conductive film G1(i)p.
[0149] Another group of pixel circuits 530(1,j) to 530(m,j) are arranged in a column direction (the direction indicated by the arrow C1 in the figure) intersecting the row direction, and each of the other group of pixel circuits 530(1,j) to 530(m,j) includes a pixel circuit 530(i,j). The other group of pixel circuits 530(1,j) to 530(m,j) are electrically connected to the conductive film S1(j)q.
[0150] <Configuration Example 7 of Display Device> In a display device of one embodiment of the present invention, a set of light-emitting devices 550(i,j) includes light-emitting devices 550(i,j)(p,1) to 550(i,j)(p,t) (see FIG. 8A ). Note that the light-emitting devices 550(i,j)(p,1) to 550(i,j)(p,t) are arranged in the row direction.
[0151] <Configuration Example 8 of Display Device> In a display device of one embodiment of the present invention, a set of light-emitting devices 550(i,j) may include light-emitting devices 550(i,j)(p,1) to 550(i,j)(p,t), and the light-emitting devices 550(i,j)(p,1) to 550(i,j)(p,t) may be arranged in a column direction (see FIG. 8B ).
[0152] <Configuration Example 9 of Display Device> In a display device of one embodiment of the present invention, a set of light-emitting devices 550(i,j) may include light-emitting devices 550(i,j)(p,1) to 550(i,j)(p,t), and the light-emitting devices 550(i,j)(p,1) to 550(i,j)(p,t) may be arranged in a matrix (see FIGS. 9A and 9B ).
[0153] This embodiment mode can be combined with the descriptions of other embodiment modes as appropriate.
[0154] Embodiment 2 In this embodiment, a structure of a display device according to one embodiment of the present invention will be described with reference to FIGS.
[0155] 10A is a perspective view illustrating a structure of a display device according to one embodiment of the present invention, and FIG. 10B is a top view illustrating a part of the display device according to one embodiment of the present invention illustrated in FIG. 10A.
[0156] 11A is a perspective view illustrating a structure of a display device of one embodiment of the present invention, and FIG. 11B is a top view illustrating a part of the display device of one embodiment of the present invention illustrated in FIG. 11A.
[0157] 12A is a perspective view illustrating a structure of a display device of one embodiment of the present invention, and FIG. 12B is a top view illustrating a part of the display device of one embodiment of the present invention illustrated in FIG. 12A.
[0158] 13A is a top view illustrating a structure of a display device of one embodiment of the present invention, and FIG. 13B is a top view illustrating a structure of a display device of one embodiment of the present invention, which is different from the structure illustrated in FIG. 13A.
[0159] FIG. 14A is a circuit diagram illustrating a pixel circuit that can be used in a display device of one embodiment of the present invention, and FIG. 14B is a timing chart illustrating the operation of the pixel circuit illustrated in FIG. 14A.
[0160] FIG. 15 is a perspective view illustrating a structure of a set of pixels that can be used in a display device of one embodiment of the present invention.
[0161] FIG. 16 is a perspective view illustrating a configuration of a set of pixels that is different from the configuration shown in FIG.
[0162] 17A is a circuit diagram illustrating a pixel circuit that can be used in a display device of one embodiment of the present invention, and FIG. 17B is a timing chart illustrating the operation of the pixel circuit illustrated in FIG. 17A.
[0163] FIG. 18 is a perspective view illustrating a configuration of a set of pixels that can be used in a display device of one embodiment of the present invention.
[0164] FIG. 19 is a perspective view illustrating a configuration of a set of pixels that is different from the configuration shown in FIG.
[0165] FIG. 20A is a circuit diagram illustrating a pixel circuit that can be used in a display device of one embodiment of the present invention, and FIG. 20B is a timing chart illustrating the operation of the pixel circuit illustrated in FIG. 20A.
[0166] FIG. 21 is a perspective view illustrating a structure of a set of pixels that can be used in a display device of one embodiment of the present invention.
[0167] FIG. 22 is a perspective view illustrating a configuration of a set of pixels that is different from the configuration shown in FIG.
[0168] FIG. 23A is a circuit diagram illustrating a pixel circuit that can be used in a display device of one embodiment of the present invention, and FIG. 23B is a timing chart illustrating the operation of the pixel circuit illustrated in FIG. 23A.
[0169] FIG. 24 is a perspective view illustrating a structure of a set of pixels that can be used in a display device of one embodiment of the present invention.
[0170] FIG. 25 is a perspective view illustrating a configuration of a set of pixels that is different from the configuration shown in FIG.
[0171] FIG. 26A is a circuit diagram illustrating a pixel circuit that can be used in a display device of one embodiment of the present invention, and FIG. 26B is a timing chart illustrating the operation of the pixel circuit illustrated in FIG. 26A.
[0172] FIG. 27 is a perspective view illustrating a structure of a set of pixels that can be used in a display device of one embodiment of the present invention.
[0173] FIG. 28 is a perspective view illustrating a configuration of a set of pixels that is different from the configuration shown in FIG.
[0174] FIG. 29 is a perspective view illustrating a configuration of a set of pixels that is different from the configurations shown in FIGS.
[0175] <Configuration Example 1 of Display Device> The display device described in this embodiment includes a set of pixels 703(i, j), a set of pixels 703(i, j+1), a set of pixels 703(i+1, j), a conductive film G1(i)p, and a conductive film G2(i)(p, q) (see FIG. 10A ).
[0176] <<Configuration Example 1 of a Set of Pixels 703(i,j)>> A set of pixels 703(i,j) includes a set of light-emitting devices 550(i,j), pads 542(i,j), pads 541(i,j), conductive materials 543(i,j), and a set of pixel circuits 530(i,j).
[0177] A set of light-emitting devices 550(i,j) are electrically connected to pads 542(i,j), which overlap pads 541(i,j), and pads 541(i,j) are electrically connected to a set of pixel circuits 530(i,j).
[0178] The conductive material 543(i,j) is sandwiched between the pad 542(i,j) and the pad 541(i,j), and the conductive material 543(i,j) electrically connects the pad 542(i,j) and the pad 541(i,j).
[0179] <<Configuration example 1 of a set of pixel circuits 530(i,j)>> A set of pixel circuits 530(i,j) includes a group of pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t), and the group of pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) includes pixel circuit 530(i,j)(p,q) (see FIG. 10B).
[0180] Furthermore, one set of pixel circuits 530(i,j) includes a group of pixel circuits 530(i,j)(1,q) to 530(i,j)(s,q), and the group of pixel circuits 530(i,j)(1,q) to 530(i,j)(s,q) includes a pixel circuit 530(i,j)(p,q). Note that s is an integer of 1 or greater. Furthermore, one set of pixel circuits 530(i,j) includes pixel circuits 530(i,j)(1,1) to 530(i,j)(s,t).
[0181] <<Configuration Example 1 of a Set of Pixels 703(i, j+1)>> Furthermore, a set of pixels 703(i, j+1) includes a set of light-emitting devices 550(i, j+1) and a set of pixel circuits 530(i, j+1), and the set of light-emitting devices 550(i, j+1) is electrically connected to the set of pixel circuits 530(i, j+1) (see FIG. 10A ).
[0182] <<Configuration Example 1 of a Set of Pixel Circuits 530(i, j+1)>> A set of pixel circuits 530(i, j+1) includes a group of pixel circuits 530(i, j+1)(p, 1) to 530(i, j+1)(p, t), and the group of pixel circuits 530(i, j+1)(p, 1) to 530(i, j+1)(p, t) includes pixel circuit 530(i, j+1)(p, q) (see FIG. 10B ). Furthermore, the set of pixel circuits 530(i, j+1) includes pixel circuits 530(i, j+1)(1, 1) to 530(i, j+1)(s, t).
[0183] <<Configuration Example 1 of a Set of Pixels 703(i+1,j)>> Furthermore, a set of pixels 703(i+1,j) includes a set of light-emitting devices 550(i+1,j) and a set of pixel circuits 530(i+1,j), and the set of light-emitting devices 550(i+1,j) is electrically connected to the set of pixel circuits 530(i+1,j) (see FIG. 10A ).
[0184] <<Configuration Example 1 of a Set of Pixel Circuits 530(i+1,j)>> A set of pixel circuits 530(i+1,j) includes a group of pixel circuits 530(i+1,j)(1,q) to 530(i+1,j)(s,q), and the group of pixel circuits 530(i+1,j)(1,q) to 530(i+1,j)(s,q) includes pixel circuit 530(i+1,j)(p,q) (see FIG. 10B ). Furthermore, the set of pixel circuits 530(i+1,j) includes pixel circuits 530(i+1,j)(1,1) to 530(i+1,j)(s,t).
[0185] <<Configuration Example 1 of Conductive Film G1(i)p>> The conductive film G1(i)p is electrically connected to a group of pixel circuits 530(i,j)(p,1) to 530(i,j)(p,t) and a group of pixel circuits 530(i,j+1)(p,1) to 530(i,j+1)(p,t).
[0186] <<Configuration Example 1 of Conductive Film G2(i)(p,q)>> The conductive film G2(i)(p,q) is electrically connected to the pixel circuit 530(i,j)(p,q) and the pixel circuit 530(i,j+1)(p,q).
[0187] As a result, for example, a signal can be supplied to one or more pixel circuits included in a set of pixel circuits 530(i,j) using the conductive film G1(i)p during a first period. Also, a signal can be supplied to one or more pixel circuits included in another set of pixel circuits 530(i,j+1) during the same first period. Also, for example, a signal can be supplied to multiple pixel circuits during the first period using the conductive film G1(i)p.
[0188] Furthermore, for example, a signal can be supplied to pixel circuits 530(i,j)(p,q) included in one set of pixel circuits 530(i,j) using the conductive film G2(i)(p,q) during the second period. Furthermore, a signal can be supplied to pixel circuits 530(i,j+1)(p,q) included in another set of pixel circuits 530(i,j+1) during the same second period. Furthermore, during the second period, the pixel circuits 530(i,j)(p,q) can supply power to the pad 541(i,j), and the pixel circuits 530(i,j+1)(p,q) can supply power to the pad 541(i,j+1).
[0189] Furthermore, the area of the pad 541(i,j) can be made closer to the area occupied by a set of pixel circuits 530(i,j). Furthermore, the area of the pad 542(i,j) can be made closer to the area occupied by a set of pixel circuits 530(i,j). Furthermore, electrical connection between the pads 541(i,j) and 542(i,j) is facilitated. Furthermore, electrical connection between a set of pixel circuits 530(i,j) and a set of light-emitting devices 550(i,j) is facilitated. Alternatively, bonding between a set of pixel circuits 530(i,j) and a set of light-emitting devices 550(i,j) is facilitated. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0190] <<Configuration Example 2 of a Set of Pixel Circuits 530(i,j)>> A set of pixel circuits 530(i,j) described in this embodiment includes, for example, pixel circuit 530(i,j)(p,q) and pixel circuit 530(i,j)(p+1,q) (see Figures 15 and 16).
[0191] <<Configuration Example 1 of Pixel Circuit 530(i,j)>> The pixel circuit 530(i,j)(p,q) includes a switch SW11, a switch SW2(p,q), a transistor M11, a capacitance C11, and a node N11 (see FIGS. 14A and 17A).
[0192] The switch SW11 has a first terminal electrically connected to the conductive film S1(j)q, a second terminal electrically connected to the node N11, and a function of controlling the conductive state or non-conductive state based on the potential of the conductive film G1(i)p.
[0193] The transistor M11 includes a gate electrode electrically connected to the node N11 and a first electrode electrically connected to the conductive film COM1.
[0194] The capacitor C11 includes a conductive film electrically connected to the node N11 and a conductive film electrically connected to the conductive film COM1.
[0195] The switch SW2(p, q) has a first terminal electrically connected to the second electrode of the transistor M11, a second terminal electrically connected to the pad 541(i, j), and a function of controlling the conductive state or non-conductive state based on the potential of the conductive film G2(i)(p, q).
[0196] <<Example 1 of Driving Method of Display Device>> A method for driving a display device of one embodiment of the present invention will be described. Specifically, the method for driving the display device will be described using the operations of the pixel circuits 530(i,j)(p,q) and 530(i,j)(p+1,q) included in a pair of pixels 703(i,j) (see FIG. 14B and FIG. 15 ). Note that a period FR1 in the drawings corresponds to one frame period.
[0197] [First Step] In the period from time t9 to time t10, a first selection signal is supplied to the conductive film G1(i)p. In addition, in the period from time t10 to time t11, a first selection signal is supplied to the conductive film G1(i)p+1.
[0198] The pixel circuit 530(i,j)(p,q) acquires an image signal from the conductive film S1(j)q based on the first selection signal. Also, the pixel circuit 530(i,j)(p+1.q) acquires an image signal from the conductive film S1(j)q+1 based on the first selection signal.
[0199] [Second Step] During the period from time t11 to time t12, a second selection signal is supplied to the conductive film G2(i)(p,q), and a predetermined potential is supplied to the conductive film COM2(i)(p,q).
[0200] The pixel circuit 530(i,j)(p,q) controls the potential of the pad 541(i,j) based on the acquired image signal and the second selection signal.
[0201] [Third Step] During the period from time t12 to time t13, a second selection signal is supplied to the conductive film G2(i)(p+1,q), and a predetermined potential is supplied to the conductive film COM2(i)(p+1,q).
[0202] The pixel circuit 530(i,j)(p+1,q) controls the potential of the pad 541(i,j) based on the acquired image signal and the second selection signal.
[0203] <<Configuration Example 3 of a Set of Pixel Circuits 530(i,j)>> A set of pixel circuits 530(i,j) described in this embodiment includes, for example, pixel circuit 530(i,j)(p,q), pixel circuit 530(i,j)(p,q+1), pixel circuit 530(i,j)(p,q+2), and pixel circuit 530(i,j)(p,q+3) (see FIGS. 18 and 19 ). Note that the display device includes conductive films S1(j)q+2 and S1(j)q+3. Furthermore, a set of light-emitting devices 550(i,j) includes light-emitting device 550(i,j)(p,q+2) and light-emitting device 550(i,j)(p,q+3). The display device also includes conductive films COM2(j)(p, q+1), COM2(j)(p, q+2), and COM2(j)(p, q+3) (see FIG. 19).
[0204] <<Example 2 of Driving Method of Display Device>> A method for driving a display device of one embodiment of the present invention will be described. Specifically, the method for driving the display device will be described using the operations of pixel circuits 530(i,j)(p,q) to 530(i,j)(p,q+3) included in a set of pixels 703(i,j) (see FIG. 17B and FIG. 18 ). Note that a period FR1 in the drawings corresponds to one frame period.
[0205] [First Step] In the period from time t10 to time t11, a first selection signal is supplied to the conductive film G1(i)p.
[0206] The pixel circuit 530(i,j)(p,q) acquires an image signal from the conductive film S1(j)q based on the first selection signal. Also, the pixel circuit 530(i,j)(p,q+1) acquires an image signal from the conductive film S1(j)q+1 based on the first selection signal.
[0207] [Second Step] During the period from time t11 to time t15, one of the conductive films G2(i)(p,q) to G2(i)(p,q+3) is selected in a predetermined order and a second selection signal is supplied to the selected conductive film. Also, one of the conductive films COM2(i)(p,q) to COM2(i)(p,q+3) is selected in a predetermined order and a predetermined potential is supplied to the selected conductive film. Note that the conductive films G2(i)(p,q) to G2(i)(p,q+3) include the conductive film G2(i)(p,q+2), and the conductive films COM2(i)(p,q) to COM2(i)(p,q+3) include the conductive film COM2(i)(p,q+2).
[0208] [Operation of pixel 702(i,j)(p,q) in the second step] For example, during the period from time t11 to time t12, the pixel circuit 530(i,j)(p,q) is supplied with a second selection signal from the conductive film G2(i)(p,q), and controls the potential of the pad 541(i,j) based on the acquired image signal.
[0209] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p, q) during the period from time t11 to time t12.
[0210] As a result, the light-emitting device 550(i,j)(p,q) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p,q) during the period from time t11 to time t12.
[0211] [Operation of pixel 702(i,j)(p,q+1) in the second step] For example, during the period from time t12 to time t13, the pixel circuit 530(i,j)(p,q+1) is supplied with a second selection signal from the conductive film G2(i)(p,q+1), and controls the potential of the pad 541(i,j) based on the acquired image signal.
[0212] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p, q+1) during the period from time t12 to time t13.
[0213] As a result, the light-emitting device 550(i,j)(p,q+1) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p,q+1) during the period from time t12 to time t13.
[0214] <Configuration Example 2 of Display Device> The display device described in this embodiment differs from Configuration Example 1 of the display device in that it has a conductive film G2(j)(p,q) instead of the conductive film G2(i)(p,q) (see FIG. 11B ). Here, the differences will be described in detail, and the above description will be used for parts where a similar configuration can be used.
[0215] <<Configuration example 1 of conductive film G2(j)(p,q)>> The conductive film G2(j)(p,q) is electrically connected to the pixel circuit 530(i,j)(p,q) and the pixel circuit 530(i+1,j)(p,q).
[0216] This allows, for example, using the conductive film G1(i)p, a signal to be supplied during a first period to one or more pixel circuits included in a set of pixel circuits 530(i, j) and a set of pixel circuits 530(i, j+1). Also, for example, using the conductive film G1(i+1)p, a signal to be supplied during a period different from the first period to one or more pixel circuits included in a set of pixel circuits 530(i+1, j).
[0217] Furthermore, for example, a signal can be supplied to pixel circuits 530(i,j)(p,q) included in one set of pixel circuits 530(i,j) using the conductive film G2(j)(p,q) during the second period. Furthermore, a signal can be supplied to pixel circuits 530(i+1,j)(p,q) included in another set of pixel circuits 530(i+1,j) during the same second period. Furthermore, during the second period, the pixel circuits 530(i,j)(p,q) can supply power to the pad 541(i,j), and the pixel circuits 530(i+1,j)(p,q) can supply power to the pad 541(i+1,j). As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0218] <<Configuration Example 4 of a Set of Pixel Circuits 530(i,j)>> A set of pixel circuits 530(i,j) described in this embodiment includes, for example, pixel circuit 530(i,j)(p,q), pixel circuit 530(i,j)(p,q+1), pixel circuit 530(i,j)(p,q+2), and pixel circuit 530(i,j)(p,q+3) (see Figures 21 and 22).
[0219] Configuration Example 2 of Pixel Circuit 530(i,j) This configuration example differs from Configuration Example 1 of pixel circuit 530(i,j) in that switch SW2(p,q) has a function of controlling the conductive state or non-conductive state based on the potential of conductive film G2(j)(p,q) instead of conductive film G2(i)(p,q) (see FIGS. 20A and 23A ). Here, the differences will be described in detail, and the above description will be used for parts where a similar configuration can be used.
[0220] <<Example 3 of Driving Method of Display Device>> A method for driving a display device of one embodiment of the present invention will be described. Specifically, the method for driving the display device will be described using the operations of pixel circuits 530(i,j)(p,q) to 530(i,j)(p,q+3) included in a set of pixels 703(i,j) (see FIG. 20B and FIG. 21 ). Note that a period FR1 in the drawings corresponds to one frame period.
[0221] [First Step] In the period from time t10 to time t11, a first selection signal is supplied to the conductive film G1(i)p.
[0222] The pixel circuit 530(i,j)(p,q) acquires an image signal from the conductive film S1(j)q based on the first selection signal. Also, the pixel circuit 530(i,j)(p,q+1) acquires an image signal from the conductive film S1(j)q+1 based on the first selection signal.
[0223] [Second Step] During the period from time t11 to time t15, one of the conductive films G2(j)(p,q) to G2(j)(p,q+3) is selected in a predetermined order and a second selection signal is supplied to the selected conductive film. Also, one of the conductive films COM2(i)(p,q) to COM2(i)(p,q+3) is selected in a predetermined order and a predetermined potential is supplied to the selected conductive film.
[0224] [Operation of pixel 702(i,j)(p,q) in the second step] For example, during the period from time t11 to time t12, the pixel circuit 530(i,j)(p,q) is supplied with a second selection signal from the conductive film G2(j)(p,q), and controls the potential of the pad 541(i,j) based on the acquired image signal.
[0225] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p, q) during the period from time t11 to time t12.
[0226] As a result, the light-emitting device 550(i,j)(p,q) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p,q) during the period from time t11 to time t12.
[0227] [Operation of pixel 702(i,j)(p,q+1) in the second step] For example, during the period from time t12 to time t13, pixel circuit 530(i,j)(p,q+1) is supplied with a second selection signal from conductive film G2(j)(p,q+1), and controls the potential of pad 541(i,j) based on the acquired image signal.
[0228] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p, q+1) during the period from time t12 to time t13.
[0229] As a result, the light-emitting device 550(i,j)(p,q+1) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p,q+1) during the period from time t12 to time t13.
[0230] <<Configuration Example 5 of a Set of Pixel Circuits 530(i,j)>> A set of pixel circuits 530(i,j) described in this embodiment includes, for example, pixel circuits 530(i,j)(p,q) to 530(i,j)(p,q+3) and pixel circuits 530(i,j)(p+1,q) to 530(i,j)(p+1,q+3) (see Figures 24 and 25).
[0231] <<Example 4 of Driving Method of Display Device>> A method for driving a display device of one embodiment of the present invention will be described. Specifically, the method for driving the display device will be described using the operations of pixel circuits 530(i,j)(p,q) to 530(i,j)(p+1,q+3) included in a set of pixels 703(i,j) (see FIG. 23B and FIG. 24 ). Note that a period FR1 in the drawings corresponds to one frame period.
[0232] [First Step] In the period from time t9 to time t10, a first selection signal is supplied to the conductive film G1(i)p. In addition, in the period from time t10 to time t11, a first selection signal is supplied to the conductive film G1(i)p+1.
[0233] The pixel circuit 530(i,j)(p,q) acquires an image signal from the conductive film S1(j)q based on the first selection signal. Also, the pixel circuit 530(i,j)(p,q+1) acquires an image signal from the conductive film S1(j)q+1 based on the first selection signal.
[0234] [Second Step] During the period from time t11 to time t19, one of the conductive films G2(j)(p, q) to G2(j)(p+1, q+3) is selected in a predetermined order and a second selection signal is supplied to the selected conductive film. Also, one of the conductive films COM2(i)(p, q) to COM2(i)(p, q+3) is selected in a predetermined order and a predetermined potential is supplied to the selected conductive film.
[0235] [Operation of pixel 702(i,j)(p,q) in the second step] For example, during the period from time t11 to time t12, the pixel circuit 530(i,j)(p,q) is supplied with a second selection signal from the conductive film G2(j)(p,q), and controls the potential of the pad 541(i,j) based on the acquired image signal.
[0236] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p, q) during the period from time t11 to time t12.
[0237] As a result, the light-emitting device 550(i,j)(p,q) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p,q) during the period from time t11 to time t12.
[0238] [Operation of pixel 702(i,j)(p,q+1) in the second step] For example, during the period from time t12 to time t13, pixel circuit 530(i,j)(p,q+1) is supplied with a second selection signal from conductive film G2(j)(p,q+1), and controls the potential of pad 541(i,j) based on the acquired image signal.
[0239] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p, q+1) during the period from time t12 to time t13.
[0240] As a result, the light-emitting device 550(i,j)(p,q+1) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p,q+1) during the period from time t12 to time t13.
[0241] [Operation of pixel 702(i,j)(p+1,q) in the second step] For example, during the period from time t15 to time t16, pixel circuit 530(i,j)(p+1,q) is supplied with a second selection signal from conductive film G2(j)(p+1,q), and controls the potential of pad 541(i,j) based on the acquired image signal.
[0242] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p+1, q) during the period from time t15 to time t16.
[0243] As a result, the light-emitting device 550(i,j)(p+1,q) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p+1,q) during the period from time t15 to time t16.
[0244] <Configuration Example 3 of Display Device> The display device described in this embodiment differs from Configuration Example 1 of the display device in that it has conductive films G3(i)p and G3(j)q instead of conductive film G2(i)(p,q) (see FIG. 12B ). Here, the differences will be described in detail, and the above description will be used for parts where a similar configuration can be used.
[0245] <<Configuration Example 1 of Conductive Film G3(i)p>> The conductive film G3(i)p is electrically connected to the pixel circuit 530(i,j)(p,q) and the pixel circuit 530(i,j+1)(p,q).
[0246] <<Configuration Example 1 of Conductive Film G3(j)q>> The conductive film G3(j)q is electrically connected to the pixel circuit 530(i,j)(p,q) and the pixel circuit 530(i+1,j)(p,q).
[0247] As a result, for example, a signal can be supplied to one or more pixel circuits included in a set of pixel circuits 530(i,j) using the conductive film G1(i)p during a first period. Also, a signal can be supplied to one or more pixel circuits included in another set of pixel circuits 530(i,j+1) during the same first period. Also, for example, a signal can be supplied to multiple pixel circuits during the first period using the conductive film G1(i)p.
[0248] Furthermore, for example, a signal can be supplied to pixel circuits 530(i,j)(p,q) included in a set of pixel circuits 530(i,j) using conductive films G3(i)p and G3(j)q during the second period. Furthermore, for example, a signal can be supplied to pixel circuits 530(i,j+1)(p,q) included in a set of pixel circuits 530(i,j+1) using conductive films G3(i+1)p and G3(j)q during the second period. Furthermore, for example, a signal can be supplied to pixel circuits 530(i+1,j)(p,q) included in a set of pixel circuits 530(i+1,j) using conductive films G3(i+1)p and G3(j)q during the second period.
[0249] Furthermore, by using two conductive films that intersect with each other, for example, conductive film G3(i)p and conductive film G3(j)q, one pixel circuit from a set of pixel circuits 530(i,j) is selected and a signal is supplied to the selected pixel circuit, thereby reducing the number of conductive films. As a result, a novel display device that is excellent in convenience, usability, and reliability can be provided.
[0250] <<Configuration Example 6 of a Set of Pixel Circuits 530(i,j)>> A set of pixel circuits 530(i,j) described in this embodiment includes, for example, pixel circuits 530(i,j)(p,q) to 530(i,j)(p,q+3) and pixel circuits 530(i,j)(p+1,q) to 530(i,j)(p+1,q+3) (see Figures 27, 28, and 29).
[0251] <<Configuration Example 3 of Pixel Circuit 530(i,j)>> Configuration Example 3 of Pixel Circuit 530(i,j)> differs from Configuration Example 1 of Pixel Circuit 530(i,j) in that it includes switches SW3p and SW3q instead of switch SW2(p,q) (see FIG. 26A ). Here, the differences will be described in detail, and the above description will be used for parts where a similar configuration can be used.
[0252] The switch SW3p has a first terminal electrically connected to the second electrode of the transistor M11, and has a function of controlling the conductive state or non-conductive state based on the potential of the conductive film G3(i)p.
[0253] The switch SW3q has a first terminal electrically connected to the second terminal of the switch SW3p, a second terminal electrically connected to the pad 541(i, j), and a function of controlling the conductive state or non-conductive state based on the potential of the conductive film G3(j)q.
[0254] <<Example 5 of Driving Method of Display Device>> A method for driving a display device of one embodiment of the present invention will be described. Specifically, the method for driving the display device will be described using the operations of pixel circuits 530(i,j)(p,q) to 530(i,j)(p+1,q+3) included in a set of pixels 703(i,j) (see FIG. 26B and FIG. 27 ). Note that a period FR1 in the drawings corresponds to one frame period.
[0255] [First Step] In the period from time t9 to time t10, a first selection signal is supplied to the conductive film G1(i)p. In addition, in the period from time t10 to time t11, a first selection signal is supplied to the conductive film G1(i)p+1.
[0256] The pixel circuit 530(i,j)(p,q) acquires an image signal from the conductive film S1(j)q based on the first selection signal. Also, the pixel circuit 530(i,j)(p,q+1) acquires an image signal from the conductive film S1(j)q+1 based on the first selection signal.
[0257] [Second Step] During the period from time t11 to time t15, while supplying the third selection signal to the conductive film G3(i)p, one of the conductive films G3(j)q to G3(j)q+3 is selected in a predetermined order and a fourth selection signal is supplied to it. Also, one of the conductive films COM2(i)(p,q) to COM2(i)(p,q+3) is selected in a predetermined order and a predetermined potential is supplied to it.
[0258] [Operation of pixel 702(i,j)(p,q) in the second step] For example, the pixel circuit 530(i,j)(p,q) is supplied with a third selection signal from the conductive film G3(i)p during the period from time t11 to time t15. Also, the pixel circuit 530(i,j)(p,q) is supplied with a fourth selection signal from the conductive film G3(j)q during the period from time t11 to time t12, and controls the potential of the pad 541(i,j) based on the acquired image signal.
[0259] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p, q) during the period from time t11 to time t12.
[0260] As a result, the light-emitting device 550(i,j)(p,q) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p,q) during the period from time t11 to time t12.
[0261] [Operation of pixel 702(i,j)(p,q+1) in the second step] For example, the pixel circuit 530(i,j)(p,q+1) receives a third selection signal from the conductive film G3(i)p during the period from time t11 to time t15. Also, the pixel circuit 530(i,j)(p,q+1) receives a fourth selection signal from the conductive film G3(j)q+1 during the period from time t12 to time t13, and controls the potential of the pad 541(i,j) based on the acquired image signal.
[0262] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p, q+1) during the period from time t12 to time t13.
[0263] As a result, the light-emitting device 550(i,j)(p,q+1) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p,q+1) during the period from time t12 to time t13.
[0264] [Operation of pixel 702(i,j)(p+1,q) in the second step] For example, pixel circuit 530(i,j)(p+1,q) receives a third selection signal from conductive film G3(i)p+1 during the period from time t15 to time t19. Also, a fourth selection signal is supplied from conductive film G3(j)q during the period from time t15 to time t16, and controls the potential of pad 541(i,j) based on the acquired image signal.
[0265] Furthermore, a predetermined potential is supplied to the conductive film COM2(i)(p+1, q) during the period from time t15 to time t16.
[0266] As a result, the light-emitting device 550(i,j)(p+1,q) displays at a predetermined brightness based on the potential difference between the pad 541(i,j) and the conductive film COM2(i)(p+1,q) during the period from time t15 to time t16.
[0267] <Configuration Example 4 of Display Device> A display device of one embodiment of the present invention includes a conductive film COM2(i)(p, q) (see FIG. 13A ). In addition, the display device also includes a conductive film COM2(i+1)(p, q) and a conductive film COM2(j+1)(p, q).
[0268] <<Configuration Example 1 of a Set of Light-Emitting Devices 550(i,j)>> The set of light-emitting devices 550(i,j) includes light-emitting device 550(i,j)(p,q). The set of light-emitting devices 550(i,j) also includes light-emitting device 550(i,j)(1,1) to light-emitting device 550(i,j)(s,t).
[0269] The display device or light-emitting device of this embodiment has a function of displaying an image using a light-emitting diode. Since a light-emitting diode is a self-luminous device, when a light-emitting diode is used as a display device, the display device does not need a backlight and does not need to be provided with a polarizing plate. Therefore, the power consumption of the display device can be reduced, and the display device can be made thinner and lighter. Furthermore, a display device using a light-emitting diode as a display device can increase luminance (for example, 5000 cd / m 2 or more, preferably 10,000 cd / m 2 Furthermore, the display device has a high display quality due to its high contrast and wide viewing angle. Furthermore, the use of an inorganic material as the light-emitting material can extend the life of the display device and improve its reliability.
[0270] In this embodiment, a micro LED is used as the light emitting diode. In this embodiment, a micro LED having a double heterojunction is described. However, the light emitting diode is not particularly limited, and for example, a micro LED having a quantum well junction, an LED using nanocolumns, or the like may also be used.
[0271] The area of the light-emitting diode's light-emitting region is 1 mm 2 Preferably, it is less than 10,000 μm 2 More preferably, 3000 μm or less 2 More preferably, 700 μm or less 2More preferably, the area of the region is 1 μm or less. 2 More than 10 μm is preferable. 2 More than 100 μm is preferable. 2 In this specification, the area of the light-emitting region is 10,000 μm 2 The following light-emitting diodes may be referred to as micro-LEDs or micro-light-emitting diodes.
[0272] The display device of this embodiment preferably includes a transistor having a channel formation region in a metal oxide layer. A transistor using a metal oxide can reduce power consumption. Therefore, by combining a transistor with a micro LED, a display device with extremely reduced power consumption can be realized.
[0273] The display device of this embodiment mode preferably includes a transistor having a channel formation region in a semiconductor substrate (for example, a silicon substrate), which enables high-speed operation of the circuit.
[0274] The display device of this embodiment preferably includes a stack of a transistor having a channel formation region in a semiconductor substrate and a transistor having a channel formation region in a metal oxide layer, which enables high-speed operation of the circuit and extremely low power consumption.
[0275] <<Configuration Example 1 of a Set of Light-Emitting Devices 550(i, j+1)>> The set of light-emitting devices 550(i, j+1) includes a light-emitting device 550(i, j+1)(p, q). The set of light-emitting devices 550(i, j+1) also includes light-emitting devices 550(i, j+1)(1, 1) to 550(i, j+1)(s, t).
[0276] <<Configuration Example 1 of a Set of Light-Emitting Devices 550(i+1,j)>> The set of light-emitting devices 550(i+1,j) includes light-emitting device 550(i+1,j)(p,q). The set of light-emitting devices 550(i+1,j) also includes light-emitting device 550(i+1,j)(1,1) to light-emitting device 550(i+1,j)(s,t).
[0277] <<Configuration Example 1 of Conductive Film COM2(i)(p,q)>> The conductive film COM2(i)(p,q) is electrically connected to the light-emitting device 550(i,j)(p,q) and the light-emitting device 550(i,j+1)(p,q).
[0278] As a result, for example, using the conductive film COM2(i)(p,q), it is possible to select the light-emitting device 550(i,j+1)(p,q) included in the set of light-emitting devices 550(i,j+1) at the same time that the light-emitting device 550(i,j)(p,q) included in the set of light-emitting devices 550(i,j). Furthermore, it is possible for the pad 542(i,j) to supply power to the light-emitting device 550(i,j)(p,q) at the same time that the pad 542(i,j) supplies power to the light-emitting device 550(i,j)(p,q).
[0279] Furthermore, the area of the pad 542(i,j) can be made closer to the area occupied by a set of light-emitting devices 550(i,j). Furthermore, electrical connection between the pads 541(i,j) and 542(i,j) is facilitated. Furthermore, electrical connection between a set of pixel circuits 530(i,j) and a set of light-emitting devices 550(i,j) is facilitated. Alternatively, bonding between a set of pixel circuits 530(i,j) and a set of light-emitting devices 550(i,j) is facilitated. As a result, a novel display device with excellent convenience, usability, and reliability can be provided.
[0280] <Configuration Example 2 of a Set of Light-Emitting Devices 550(i,j)> A set of light-emitting devices 550(i,j) described in this embodiment includes a plurality of light-emitting devices including, for example, light-emitting device 550(i,j)(p,q) (see Figures 15, 18, 21, 24, and 27).
[0281] <Configuration Example 5 of Display Device> The display device described in this embodiment differs from Configuration Example 4 of the display device in that it has a conductive film COM2(j)(p,q) instead of the conductive film COM2(i)(p,q) (see FIG. 13B ). Here, the differences will be described in detail, and the above description will be used for parts where a similar configuration can be used.
[0282] <<Configuration Example 1 of Conductive Film COM2(j)(p,q)>> The conductive film COM2(j)(p,q) is electrically connected to the light-emitting device 550(i,j)(p,q) and the light-emitting device 550(i+1,j)(p,q).
[0283] As a result, for example, using the conductive film COM2(j)(p,q), it is possible to select the light-emitting device 550(i+1,j)(p,q) included in the set of light-emitting devices 550(i,j) at the timing when the light-emitting device 550(i,j)(p,q) included in the set of light-emitting devices 550(i,j) is selected. Furthermore, it is possible for the pad 542(i,j) to supply power to the light-emitting device 550(i+1,j)(p,q) at the timing when the pad 542(i,j) supplies power to the light-emitting device 550(i,j)(p,q). As a result, it is possible to provide a novel display device that is highly convenient, useful, and reliable.
[0284] <<Configuration Example 3 of a Set of Light-Emitting Devices 550(i,j)>> A set of light-emitting devices 550(i,j) described in this embodiment includes a plurality of light-emitting devices including, for example, light-emitting device 550(i,j)(p,q) and light-emitting device 550(i,j)(p+1,q) (see FIGS. 16 , 19 , 22 , 25 , and 29 ). Note that light-emitting device 550(i,j)(p+1,q) is electrically connected to conductive film COM2(j)(p+1,q).
[0285] This embodiment mode can be combined with the descriptions of other embodiment modes as appropriate.
[0286] Embodiment 3 In this embodiment, a display device and a display system which are one embodiment of the present invention will be described with reference to FIGS.
[0287] FIG. 30 is a block diagram illustrating a structure of a display device of one embodiment of the present invention.
[0288] FIG. 31 is a block diagram illustrating the configuration of the display unit shown in FIG.
[0289] FIG. 32 is a block diagram illustrating a structure of a display device of one embodiment of the present invention.
[0290] 33A and 33B are block diagrams illustrating the configuration of the pixel shown in FIG. 32.
[0291] FIG. 34 is a block diagram illustrating a structure of a display device of one embodiment of the present invention.
[0292] FIG. 35A is a flowchart relating to the correction method, and FIG. 35B is a schematic diagram illustrating the correction method.
[0293] 30 shows a block diagram for explaining each component included in the display device 10. The display device includes a driver circuit 40, a functional circuit 50, and a display unit 60.
[0294] <<Configuration Example 1 of Drive Circuit 40>> The drive circuit 40 includes, as an example, a gate driver 41 and a source driver 42. The gate driver 41 has a function of driving a plurality of gate lines GL for outputting signals to the pixel circuits 62R, 62G, and 62B. The source driver 42 has a function of driving a plurality of source lines SL for outputting signals to the pixel circuits 62R, 62G, and 62B. The drive circuit 40 also supplies voltages for displaying images in the pixel circuits 62R, 62G, and 62B to the pixel circuits 62R, 62G, and 62B via a plurality of wirings.
[0295] <<Configuration Example 1 of Functional Circuit 50>> The functional circuit 50 has a CPU 51, which can be used for arithmetic processing of data. The CPU 51 also has a CPU core 53. The CPU core 53 has a flip-flop 80 for temporarily holding data used for the arithmetic processing. The flip-flop 80 has a plurality of scan flip-flops 81, and each scan flip-flop 81 is electrically connected to a backup circuit 82 provided in the display unit 60. The flip-flop 80 inputs and outputs data of the scan flip-flops (backup data) to and from the backup circuit 82.
[0296] <Display Unit 60> With reference to FIGS. 31 and 30, a configuration example of the arrangement of the backup circuit 82 and pixel circuits 62R, 62G, and 62B, which are sub-pixels, in the display unit 60 will be described.
[0297] 31 illustrates a display unit 60 in which a plurality of pixels 61 are arranged in a matrix. Each pixel 61 includes pixel circuits 62R, 62G, and 62B as well as a backup circuit 82. As described above, the backup circuit 82 and the pixel circuits 62R, 62G, and 62B can all be formed using OS transistors and therefore can be arranged within the same pixel.
[0298] The display unit 60 has a plurality of pixels 61, each of which is provided with pixel circuits 62R, 62G, and 62B, and a backup circuit 82. As described in Fig. 31 , the backup circuit 82 does not necessarily have to be arranged within the pixel 61, which is the repeating unit. The backup circuit 82 can be arranged freely depending on the shape of the display unit 60, the shapes of the pixel circuits 62R, 62G, and 62B, etc.
[0299] 32 is a block diagram schematically illustrating a structural example of a display device 10 that is a display device of one embodiment of the present invention. The display device 10 includes a layer 20 and a layer 30. The layer 30 can be stacked, for example, above the layer 20. An interlayer insulator or a conductor for electrical connection between different layers can be provided between the layer 20 and the layer 30.
[0300] <<Layer 20>> The transistors provided in the layer 20 can be, for example, transistors having silicon in their channel formation regions (also referred to as Si transistors), such as transistors having single crystal silicon in their channel formation regions. In particular, when a transistor having single crystal silicon in its channel formation region is used as the transistor provided in the layer 20, the on-state current of the transistor can be increased. Therefore, it is preferable because the circuit included in the layer 20 can be driven at high speed. In addition, Si transistors can be formed by microfabrication to have a channel length of 3 nm to 10 nm, and therefore the display device 10 can be provided with an accelerator such as a CPU or a GPU, an application processor, or the like.
[0301] The layer 20 is provided with a driving circuit 40 and a functional circuit 50. The Si transistors in the layer 20 can increase the on-current of the transistors, so that each circuit can be driven at high speed.
[0302] <<Configuration Example 2 of the Drive Circuit 40>> The drive circuit 40 includes a gate line drive circuit, a source line drive circuit, and the like for driving the pixel circuits 62R, 62G, and 62B. As an example, the drive circuit 40 includes a gate line drive circuit and a source line drive circuit for driving the pixels 61 of the display unit 60. By arranging the drive circuit 40 in a layer 20 different from the layer 30 on which the display is provided, the area occupied by the display unit in the layer 30 can be increased. The drive circuit 40 may also include an LVDS (Low Voltage Differential Signaling) circuit or a D / A (Digital to Analog) conversion circuit, which functions as an interface for receiving data such as image data from outside the display device 10. The Si transistors in the layer 20 can increase their on-state current. The channel length or channel width of the Si transistors may be varied depending on the operating speed of each circuit.
[0303] <<Layer 30>> The transistor provided in the layer 30 can be a bottom-gate transistor, a top-gate transistor, or the like. For example, a semiconductor containing a Group 14 element can be used for the semiconductor film. Specifically, a semiconductor containing silicon can be used for the semiconductor film. For example, hydrogenated amorphous silicon, polysilicon, or single-crystalline silicon can be used. Metal oxide can also be used for the semiconductor film. For example, an OS transistor can be used. In particular, a transistor having an oxide containing at least one of indium, an element M (wherein the element M is aluminum, gallium, yttrium, or tin), and zinc in a channel formation region is preferably used as the OS transistor. Such an OS transistor has a characteristic of extremely low off-state current. Therefore, it is preferable to use an OS transistor, particularly as a transistor provided in a pixel circuit in a display portion, because analog data written to the pixel circuit can be retained for a long period of time.
[0304] The layer 30 includes a display unit 60 having a plurality of pixels 61. Each pixel 61 includes pixel circuits 62R, 62G, and 62B that control red, green, and blue light emission. The pixel circuits 62R, 62G, and 62B function as subpixels of the pixel 61. The pixel circuits 62R, 62G, and 62B each include an OS transistor, allowing analog data written to the pixel circuit to be retained for a long period of time. Each pixel 61 in the layer 30 is also provided with a backup circuit 82. The backup circuit may also be referred to as a storage circuit or a memory circuit. The backup circuit also inputs and outputs data (backup data BD) from the scan flip-flop to and from the flip-flop 80.
[0305] 33A and 33B show a configuration example of a pixel circuit 62 applicable to the pixel circuits 62R, 62G, and 62B, and a light-emitting element 70 connected to the pixel circuit 62. Fig. 33A is a diagram showing the connection of each element, and Fig. 33B is a diagram schematically showing the hierarchical relationship between the drive circuit 40, pixel circuit 62, and light-emitting element 70.
[0306] In this specification and the like, the term “element” may be replaced with “device” in some cases. For example, a display element, a light-emitting element, and a liquid crystal element may be replaced with a display device, a light-emitting device, and a liquid crystal device, for example.
[0307] 33A and 33B includes a switch SW11, a switch SW2p, a switch SW12, a switch SWm, a transistor M11, and a capacitor C11. The switch SW11, the switch SW2p, the switch SW12, the switch SWm, and the transistor M11 can be OS transistors. Each of the switch SW11, the switch SW2p, the switch SW12, the switch SWm, and the transistor M11 preferably includes a back gate electrode. In this case, the back gate electrode can be configured to receive the same signal as the gate electrode, or a signal different from the gate electrode can be applied to the back gate electrode.
[0308] The switch SW11 has a first terminal electrically connected to the source line SL, a second terminal electrically connected to the node N11, and a function of controlling the conductive state or non-conductive state based on the potential of the gate line GL11.
[0309] The transistor M11 includes a gate electrode electrically connected to the node N11 and a first electrode electrically connected to the conductive film COM1. The conductive film COM1 is a wiring for applying a potential for supplying a current to the light-emitting element 70 and a wiring for outputting a current flowing through the pixel circuit 62 to the drive circuit 40 or the function circuit 50.
[0310] The capacitor C11 includes a conductive film electrically connected to the node N11 and a conductive film electrically connected to the conductive film COM1.
[0311] The switch SW2p has a first terminal electrically connected to the second electrode of the transistor M11, a second terminal electrically connected to the first pad 541(i, j), and a function of controlling the conductive state or non-conductive state based on the potential of the gate line GL2p.
[0312] The light-emitting element 70 has one electrode electrically connected to the first pad 541(i,j) and the other electrode electrically connected to the conductive film COM2(i)(p,q). The conductive film COM2(i)(p,q) is a wiring for applying a potential to supply a current to the light-emitting element 70.
[0313] This makes it possible to control the intensity of light emitted by the light emitting element 70 in accordance with an image signal applied to the gate electrode of the transistor M11.
[0314] The switch SW12 has a first terminal electrically connected to a wiring V0, a second terminal electrically connected to a first electrode of the transistor M11, and a function of controlling the conductive state or non-conductive state based on the potential of the gate line GL12. The wiring V0 is a wiring for applying a reference potential and a wiring for outputting a current flowing through the pixel circuit 62 to the drive circuit 40 or the functional circuit 50.
[0315] The switch SWm has a first terminal electrically connected to the wiring V1, a second terminal electrically connected to the first pad 541(i, j), and a function of controlling the conductive state or non-conductive state based on a control signal. The wiring V1 is a wiring for applying a reference potential.
[0316] This allows a current value that can be used to set pixel parameters to be output from the wiring V0 via the switches SWm and SW12. More specifically, the wiring V0 can function as a monitor line for outputting the current flowing through the transistor M11 to the outside. The current output to the wiring V0 is converted into a voltage by a source follower circuit or the like and output to the outside. Alternatively, it can be converted into a digital signal by an A-D converter or the like and output to the drive circuit 40 or the like.
[0317] <Pixel Circuit Configuration Example 2> In the configuration shown in FIG. 33B as an example, the wiring electrically connecting the pixel circuit 62 and the drive circuit 40 can be shortened, thereby reducing the wiring resistance of the wiring. This allows data to be written at high speed, thereby enabling the display device 10 to be driven at high speed. This allows the display device 10 to have a large number of pixels 61, ensuring a sufficient frame period, thereby increasing the pixel density of the display device 10. Furthermore, increasing the pixel density of the display device 10 can increase the resolution of images displayed by the display device 10. For example, the pixel density of the display device 10 can be 1000 ppi or more, 5000 ppi or more, or 7000 ppi or more. Therefore, the display device 10 can be used as a display device for AR or VR, for example, and is suitable for use in electronic devices such as HMDs, where the display unit is close to the user.
[0318] 33B illustrates that the gate line GL11, the gate line GL12, the gate line GL2p, the conductive film COM1, the wiring V0, the wiring V1, and the source line SL are supplied via wirings from the driver circuit 40 below the pixel circuit 62, but one embodiment of the present invention is not limited to this. For example, wirings that supply signals and voltages from the driver circuit 40 may be routed to the periphery of the display portion 60 and electrically connected to the pixel circuits 62 arranged in a matrix on the layer 30. In this case, it is effective to provide the gate driver 41 included in the driver circuit 40 on the layer 30. That is, it is effective to use OS transistors as the transistors of the gate driver 41. It is effective to provide part of the function of the source driver 42 included in the driver circuit 40 on the layer 30. For example, it is effective to provide a demultiplexer in the layer 30 that distributes signals output from the source driver 42 to each source line. It is effective to use OS transistors as the transistors of the demultiplexer.
[0319] <<Backup Circuit 82>> A memory including an OS transistor is suitable for the backup circuit 82. A backup circuit including an OS transistor has advantages such as being able to suppress a voltage drop corresponding to the data to be backed up and consuming almost no power to retain the data, due to the feature of the OS transistor that the off-state current is extremely small. The backup circuit 82 including an OS transistor can be provided in the display unit 60 in which a plurality of pixels 61 are arranged. FIG. 32 illustrates a state in which the backup circuit 82 is provided for each pixel 61.
[0320] The backup circuit 82 formed of an OS transistor can be stacked with the layer 20 having a Si transistor. The backup circuit 82 may be arranged in a matrix similar to the subpixels in the pixel 61, or may be arranged for each of a plurality of pixels. That is, the backup circuit 82 can be arranged in the layer 30 without being restricted by the arrangement of the pixels 61. This increases the degree of freedom in the layout of the display unit / circuit, and allows the backup circuit 82 to be arranged without increasing the circuit area, thereby increasing the storage capacity of the backup circuit 82 required for arithmetic processing.
[0321] <Configuration Example 3 of Display Device> FIG. 34 shows a modification of each configuration of the display device 10 described above.
[0322] The block diagram of the display device 10A shown in FIG. 34 corresponds to a configuration in which an accelerator 52 is added to the functional circuit 50 in the display device 10 of FIG.
[0323] The accelerator 52 functions as a dedicated arithmetic circuit for the product-sum operation of the artificial neural network NN. The operation using the accelerator 52 can perform processes such as up-converting display data to correct the contours of an image. While the accelerator 52 is performing the operation, the CPU 51 can be configured to be power-gated to reduce power consumption.
[0324] <Configuration Example of Display System> In addition, in a display device according to one embodiment of the present invention, pixel circuits and functional circuits can be stacked, and therefore defective pixels can be detected using the functional circuits provided below the screen circuits. By using information about the defective pixels, display defects due to the defective pixels can be corrected, and normal display can be achieved.
[0325] Part of the correction method exemplified below may be executed by a circuit provided outside the display device, or part of the correction method may be executed by the drive circuit 40 of the display device 10.
[0326] A more specific example of the correction method will be described below. Fig. 35A is a flowchart of the correction method described below.
[0327] First, in step S1, the correction operation is started.
[0328] Next, in step S2, the pixel current is read out. For example, each pixel can be driven to output a current to a monitor line electrically connected to the pixel.
[0329] Next, in step S3, the read current is converted into a voltage. At this time, if a digital signal is to be handled in subsequent processing, the voltage can be converted into digital data in step S3. For example, analog data can be converted into digital data by using an analog-to-digital converter (ADC).
[0330] Next, in step S4, pixel parameters for each pixel are obtained based on the obtained data, such as the threshold voltage or field effect mobility of the driving transistor, the threshold voltage of the light-emitting element, and the current value at a predetermined voltage.
[0331] Next, in step S5, each pixel is judged to be abnormal based on the pixel parameter. For example, if the value of the pixel parameter exceeds (or falls below) a predetermined threshold value, the pixel is recognized as an abnormal pixel.
[0332] The abnormal pixels include dark spot defects with significantly low brightness relative to the input data potential, and bright spot defects with significantly high brightness.
[0333] In step S5, the address of the abnormal pixel and the type of defect can be identified and acquired.
[0334] Subsequently, in step S6, a correction process is performed.
[0335] An example of the correction process will be described with reference to Fig. 35B. Fig. 35B schematically shows 3 x 3 pixels. Here, the central pixel is assumed to be pixel 61D, which is a dark point defect. Fig. 35B schematically shows a state in which pixel 61D is turned off and the surrounding pixels 61N are turned on at a predetermined brightness.
[0336] A dark point defect is a defect in which the brightness of the pixel is unlikely to reach normal brightness even if a correction is made to increase the data potential input to the pixel. Therefore, as shown in Figure 35B, a correction is made to increase the brightness of pixel 61N surrounding pixel 61D, which is a dark point defect. This makes it possible to display a normal image even if a dark point defect occurs.
[0337] In the case of a bright spot defect, the bright spot defect can be made less noticeable by lowering the brightness of the surrounding pixels.
[0338] In particular, in the case of high-resolution display devices (e.g., 1000 ppi or more), it is difficult to visually recognize each pixel separately, so it is particularly effective to use a correction method that compensates for abnormal pixels using surrounding pixels.
[0339] On the other hand, it is preferable to correct the defective pixels such as dark spots and bright spots so that no data potential is input.
[0340] In this way, correction parameters can be set for each pixel. By applying the correction parameters to input image data, corrected image data can be generated to display an optimal image on the display device 10.
[0341] Furthermore, since variations exist in pixel parameters not only for abnormal pixels and pixels surrounding the abnormal pixels but also for pixels not determined to be abnormal pixels, unevenness due to the variations may be visible when an image is displayed. Therefore, for pixels not determined to be abnormal pixels, correction parameters can be set to cancel (level out) the variations in pixel parameters. For example, a reference value based on the median or average value of pixel parameters for some or all pixels can be set, and a correction value for canceling the difference between the pixel parameters of a specific pixel and the reference value can be set as the correction parameter for that pixel.
[0342] Furthermore, for pixels surrounding an abnormal pixel, it is preferable to set correction data that takes into account both the amount of correction for compensating for the abnormal pixel and the amount of correction for canceling variations in pixel parameters.
[0343] Then, in step S7, the correction operation is completed.
[0344] Thereafter, an image can be displayed based on the correction parameters obtained in the above correction operation and the input image data.
[0345] A neural network may be used as one of the correction operations. When performing calculations based on an artificial neural network in the above-described display correction system, the system is configured to repeatedly perform product-sum operations. Calculations using the accelerator 52 can correct the above-described display defects. Power gating control of the CPU 51 can be configured to reduce power consumption during calculations performed by the accelerator 52. For example, the neural network can determine correction parameters based on inference results obtained by machine learning. For example, the correction parameters can be estimated by performing calculations based on artificial neural networks such as deep neural networks (DNNs), convolutional neural networks (CNNs), recurrent neural networks (RNNs), autoencoders, deep Boltzmann machines (DBMs), and deep belief networks (DBNs). When determining correction parameters using a neural network, high-precision correction can be performed to prevent abnormal pixels from becoming noticeable, even without using detailed correction algorithms.
[0346] The above is the explanation of the correction method.
[0347] The calculations performed by the display correction system to correct the current flowing through the pixels can be performed by the CPU 51, which can continuously store data during the calculation as backup data. This is particularly effective when performing computations that require a huge amount of calculations, such as calculations based on artificial neural networks. By making the CPU 51 function as an application processor, it is possible to reduce display defects and power consumption by combining it with a drive that allows the frame frequency to be varied.
[0348] This embodiment mode can be combined with the descriptions of other embodiment modes as appropriate.
[0349] Embodiment 4 In this embodiment, a cross-sectional structure example of a display device 10 which is one embodiment of the present invention will be described with reference to FIGS.
[0350] FIG. 36 is a cross-sectional view illustrating a structure of a display device according to one embodiment of the present invention.
[0351] FIG. 37 is a cross-sectional view illustrating a structure of a display device according to one embodiment of the present invention, which is different from the structure illustrated in FIG.
[0352] FIG. 38 is a cross-sectional view illustrating a structure of a display device according to one embodiment of the present invention, which is different from the structure illustrated in FIG.
[0353] FIG. 39 is a cross-sectional view illustrating a structure of a display device according to one embodiment of the present invention, which is different from the structure shown in FIG.
[0354] FIG. 40 is a cross-sectional view illustrating a structure of a display device according to one embodiment of the present invention, which differs from the structures shown in FIGS.
[0355] FIG. 41 is a cross-sectional view illustrating a structure of a display device according to one embodiment of the present invention, which differs from the structures shown in FIGS.
[0356] <Configuration Example 1 of Display Device> FIG. 36 is a cross-sectional view showing a configuration example of a display device 10. The display device 10 includes an insulator 421 and a substrate 705, and the insulator 421 and the substrate 705 are attached to each other with a sealant 712. An OS transistor is preferably used for the pixel circuit. At least a part of the driver circuit may be formed using an OS transistor. At least a part of the functional circuit may be formed using an OS transistor. At least a part of the driver circuit may be externally provided. At least a part of the functional circuit may be externally provided.
[0357] <Insulator 421, Insulator 214, and Insulator 216> Any of various insulator substrates such as a glass substrate or a sapphire substrate can be used as the insulator 421. The insulator 214 is provided over the insulator 421, and the insulator 216 is provided over the insulator 214.
[0358] <<Insulator 222, Insulator 224, Insulator 254, Insulator 280, Insulator 274, Insulator 281>> Over the insulator 216, the insulator 222, the insulator 224, the insulator 254, the insulator 280, the insulator 274, and the insulator 281 are provided.
[0359] The insulators 421, 214, 280, 274, and 281 function as interlayer films and may also function as planarization films that cover the uneven shapes below them.
[0360] <<Insulator 361>> The insulator 361 is provided on the insulator 281. The conductor 317 and the conductor 337 are embedded in the insulator 361. Here, the height of the top surface of the conductor 337 and the height of the top surface of the insulator 361 can be made approximately the same.
[0361] <<Insulator 363>> The insulator 363 is provided on the conductor 337 and the insulator 361. The conductors 347, 353, 355, and 357 are embedded in the insulator 363. Here, the height of the top surfaces of the conductors 353, 355, and 357 can be made approximately the same as the height of the top surface of the insulator 363.
[0362] The conductors 341, 343, and 351 are embedded in the insulator 363. Here, the height of the top surface of the conductor 351 and the height of the top surface of the insulator 363 can be made to be approximately the same.
[0363] The insulators 361 and 363 function as interlayer films and may also function as planarizing films that cover uneven shapes below them. For example, the top surface of the insulator 363 may be planarized by planarization treatment using a chemical mechanical polishing (CMP) method or the like to improve the planarity.
[0364] <<Connection Electrode 760>> A connection electrode 760 is provided on the conductor 353, the conductor 355, the conductor 357, and the insulator 363. An anisotropic conductor 780 is provided so as to be electrically connected to the connection electrode 760, and an FPC (Flexible Printed Circuit) 716 is provided so as to be electrically connected to the anisotropic conductor 780. Various signals and the like are supplied to the display device 10 from outside the display device 10 via the FPC 716.
[0365] 36 shows three conductors, namely, the conductor 353, the conductor 355, and the conductor 357, as conductors having a function of electrically connecting the connection electrode 760 and the conductor 347; however, one embodiment of the present invention is not limited to this. The number of conductors having a function of electrically connecting the connection electrode 760 and the conductor 347 may be one, two, or four or more. By providing a plurality of conductors having a function of electrically connecting the connection electrode 760 and the conductor 347, contact resistance can be reduced.
[0366] <<Transistor 750>> A transistor 750 is provided over the insulator 214. The transistor 750 can be the transistor provided in the layer 30 described in Embodiment 3. For example, the transistor 750 can be a transistor provided in the pixel circuit 62. An OS transistor can be suitably used as the transistor 750. An OS transistor has an extremely low off-state current. Therefore, the retention time of image data and the like can be extended, thereby reducing the frequency of a refresh operation. Therefore, the power consumption of the display device 10 can be reduced.
[0367] The transistor 750 can be provided in the backup circuit 82. An OS transistor can be preferably used as the transistor 750. An OS transistor has an extremely low off-state current. Therefore, data stored in the flip-flop can be retained even during a period when the shared power supply voltage is stopped. This allows the CPU to operate normally (intermittently stop the power supply voltage). Therefore, the power consumption of the display device 10 can be reduced.
[0368] Conductors 301a and 301b are embedded in the insulators 254, 280, 274, and 281. The conductor 301a is electrically connected to one of the source and the drain of the transistor 750, and the conductor 301b is electrically connected to the other of the source and the drain of the transistor 750. Here, the height of the top surfaces of the conductors 301a and 301b can be made approximately the same as the height of the top surface of the insulator 281.
[0369] The conductors 311, 313, 331, a capacitor 790, a conductor 333, and a conductor 335 are embedded in the insulator 361. The conductors 311 and 313 are electrically connected to the transistor 750 and function as wirings. The conductors 333 and 335 are electrically connected to the capacitor 790. Here, the height of the top surfaces of the conductors 331, 333, and 335 can be made approximately the same as the height of the top surface of the insulator 361.
[0370] <<Capacitor 790>> As shown in Fig. 36 , the capacitor 790 has a lower electrode 321 and an upper electrode 325. An insulator 323 is provided between the lower electrode 321 and the upper electrode 325. That is, the capacitor 790 has a layered structure in which the insulator 323, which functions as a dielectric, is sandwiched between a pair of electrodes. Note that Fig. 36 shows an example in which the capacitor 790 is provided on the insulator 281, but the capacitor 790 may also be provided on an insulator different from the insulator 281.
[0371] FIG. 36 shows an example in which conductors 301a, 301b, and 305 are formed in the same layer. It also shows an example in which conductors 311, 313, 317, and a lower electrode 321 are formed in the same layer. It also shows an example in which conductors 331, 333, 335, and 337 are formed in the same layer. It also shows an example in which conductors 341, 343, and 347 are formed in the same layer. It also shows an example in which conductors 351, 353, 355, and 357 are formed in the same layer. Forming multiple conductors in the same layer can simplify the manufacturing process of the display device 10, thereby reducing the manufacturing cost of the display device 10. These conductors may be formed in different layers and may contain different types of materials.
[0372] 36 includes a light-emitting element 70. The light-emitting element 70 includes a conductor 772, a light-emitting layer 786, and a conductor 788. The light-emitting layer 786 includes an inorganic compound or an organic compound.
[0373] For example, a compound semiconductor can be used for the light emitting layer 786. Specifically, the light emitting layer 786 can be sandwiched between a P-type clad layer and an N-type clad layer. This allows carriers to be recombined in the light emitting layer 786. As a result, light can be emitted due to the recombination of carriers.
[0374] For example, a laminated material laminated so as to emit blue light, a laminated material laminated so as to emit green light, or a laminated material laminated so as to emit red light can be used for the light-emitting layer 786. Specifically, a gallium phosphide compound, a gallium arsenide compound, a gallium aluminum arsenide compound, an aluminum gallium indium phosphide compound, an indium gallium nitride compound, or the like can be used for the light-emitting layer 786.
[0375] Furthermore, quantum dots or the like can be used in the light-emitting layer 786. Specifically, colloidal quantum dot materials, alloy-type quantum dot materials, core-shell-type quantum dot materials, core-type quantum dot materials, or the like can be used in the light-emitting layer 786.
[0376] A fluorescent organic compound, a phosphorescent organic compound, or the like can be used for the light-emitting layer 786. For example, a low-molecular-weight compound can be used for the light-emitting layer 786. For example, a high-molecular-weight compound can be used for the light-emitting layer 786.
[0377] For example, a mini LED can be used as the light emitting element 70. Specifically, the area of the light emitting region is 1 mm 2 Less than 50,000 μm, preferably 2 Less than or equal to 30,000 μm, more preferably 30,000 μm 2 More preferably, 10,000 μm or less 2 Below, 200 μm 2 The above mini LED can be used as the light emitting element 70.
[0378] Alternatively, a micro LED can be used as the light emitting element 70. Specifically, a light emitting element having an area of 200 μm 2 Less than 60 μm, preferably 2 Less than 15 μm, more preferably 2 More preferably, 5 μm or less2 Below, 3μm 2 The micro LED described above can be used as the light emitting element 70.
[0379] A material that transmits visible light can be used for the conductor 772 and the conductor 788. As the light-transmitting material, for example, an oxide material containing indium, zinc, tin, or the like can be used. Note that the light-emitting element 70 may have a bottom emission structure in which light is emitted to the conductor 772 side, a top emission structure in which light is emitted to the conductor 788 side, or a dual emission structure in which light is emitted to both the conductor 772 side and the conductor 788 side.
[0380] Furthermore, a material that is reflective to visible light can be used for the conductor 772 or the conductor 788. As the reflective material, for example, a material containing aluminum, silver, or the like can be used.
[0381] The light-emitting element 70 can have a micro-optical resonator (microcavity) structure. This allows light of a predetermined color (e.g., RGB) to be extracted without providing a colored layer, and the display device 10 can display a color image. By using a configuration without providing a colored layer, it is possible to suppress light absorption by the colored layer. This allows the display device 10 to display a high-brightness image and reduce the power consumption of the display device 10.
[0382] <<Pad 542, Conductive Material 543, Pad 541, Conductive Film COM2p>> The light-emitting element 70 is electrically connected to the other of the source and the drain of the transistor 750 via the conductor 772, the pad 542, the conductive material 543, the pad 541, the conductor 351, the conductor 341, the conductor 331, the conductor 313, and the conductor 301b. In other words, the conductor 772, the pad 542, the conductive material 543, the pad 541, the conductor 351, the conductor 341, the conductor 331, the conductor 313, and the conductor 301b have a function of electrically connecting the light-emitting element 70 to the pixel circuit.
[0383] The pad 542 is formed in contact with the conductor 772 .
[0384] The conductive material 543 is dispersed in, for example, the insulator 734. This provides the function of an anisotropic conductive adhesive or an anisotropic conductive film.
[0385] Alternatively, the pads 542 and 541 may be directly bonded to each other using a surface activated bonding method, for example, a metal-metal bonding method, specifically, a copper-copper bonding method.
[0386] The conductive film COM2p is formed in contact with the conductor 772. In addition, for example, a voltage for driving the light emitting element 70 at maximum luminance is supplied.
[0387] <<Color Conversion Layer CC>> The color conversion layer CC is provided so as to overlap the light emitting element 70. The color conversion layer CC also has the function of converting the color of light emitted from the light emitting element 70 into another color.
[0388] For example, a material that converts blue light emitted from the light-emitting element into green light can be used for the color conversion layer CC, and a material that converts blue light into red light can be used for the color conversion layer CC.
[0389] Furthermore, for example, a material that converts ultraviolet light emitted from the light-emitting element into blue light can be used for the color conversion layer CC. Also, a material that converts ultraviolet light into green light can be used for the color conversion layer CC. Also, a material that converts ultraviolet light into red light can be used for the color conversion layer CC.
[0390] This allows a plurality of light-emitting elements to be formed in the same process using the same material, and color conversion layers CC can be made using different materials overlaid on each light-emitting element, allowing different colors to be displayed.
[0391] A colored layer may also be provided. The colored layer is provided so as to have an area overlapping with the light-emitting element 70. By providing the colored layer, the color purity of the light extracted from the light-emitting element 70 can be increased. This allows the display device 10 to display a high-quality image. Furthermore, for example, all of the light-emitting elements 70 of the display device 10 may be light-emitting elements that emit white light.
[0392] Although not shown in FIG. 36, the display device 10 can be provided with optical members (optical substrates) such as a polarizing member, a phase difference member, an anti-reflection member, and the like.
[0393] 36, an insulator 730 is provided on the insulator 363. Here, the insulator 730 can be configured to cover a part of the pad 541.
[0394] <<Insulator 734>> The insulator 734 is sandwiched between the pad 541 and the pad 542, and functions to bond the pad 541 and the pad 542. The conductive material 543 is dispersed in the insulator 734. This provides the insulator 734 with the function of an anisotropic conductive adhesive.
[0395] The light-shielding layer 738 has a function of blocking light emitted from an adjacent region and also has a function of reducing the intensity of external light reaching the transistor 750 and the like.
[0396] <<Sealing Layer 732>> The sealing layer 732 covers the light emitting element 70. The sealing layer 732 has a function of suppressing the diffusion of impurities that impair the reliability of the light emitting element 70 from the outside of the light emitting element 70 to the inside of the light emitting element 70.
[0397] <<Structure 778 >> The structure 778 is provided between the insulator 730 and the substrate 705 and has a function of adjusting the gap between the insulator 730 and the substrate 705 .
[0398] 37 is a cross-sectional view showing a structural example of the display device 10. The display device 10 includes a substrate 701B and a substrate 705, and the substrate 701B and the substrate 705 are attached to each other with a sealing material 712. The display device 10 shown in FIG. 37 differs from the display device 10 shown in FIG. 36 in that a transistor 750 is formed over a single crystal semiconductor substrate.
[0399] <<Substrate 701B>> A single crystal semiconductor substrate such as a single crystal silicon substrate can be used as the substrate 701B. Note that a semiconductor substrate other than a single crystal semiconductor substrate may also be used as the substrate 701B.
[0400] A transistor 750 is provided over a substrate 701B. The transistor 750 can be the transistor provided in the layer 30 described in Embodiment 3. For example, the transistor 750 can be the transistor provided in the pixel circuit 62.
[0401] <<Transistor 750>> The transistor 750 can have a structure similar to that of a transistor 441 described later.
[0402] 38 is a cross-sectional view showing a structural example of the display device 10. The display device 10 includes a substrate 701 and a substrate 705, and the substrate 701 and the substrate 705 are attached to each other with a sealing material 712. The display device 10 shown in FIG. 38 differs from the display device 10 shown in FIG. 36 in that it includes a transistor 601.
[0403] <<Substrate 701>> A single crystal semiconductor substrate such as a single crystal silicon substrate can be used as the substrate 701. Note that the substrate 701 may be a semiconductor substrate other than a single crystal semiconductor substrate.
[0404] A transistor 441 and a transistor 601 are provided over a substrate 701. The transistor 441 and the transistor 601 can be the transistors provided in the layer 20 described in Embodiment 3. For example, the transistors 441 and 601 can be used as transistors in the driver circuit 40 or the functional circuit 50 included in the layer 20.
[0405] The transistor 441 includes a conductor 443 that functions as a gate electrode, an insulator 445 that functions as a gate insulator, and a part of the substrate 701, and includes a semiconductor region 447 including a channel formation region, a low-resistance region 449 a that functions as one of a source region and a drain region, and a low-resistance region 449 b that functions as the other of the source region and the drain region. The transistor 441 may be either a p-channel type or an n-channel type.
[0406] The transistor 441 is electrically isolated from other transistors by an element isolation layer 403. Fig. 38 shows a case where the transistor 441 and the transistor 601 are electrically isolated by the element isolation layer 403. The element isolation layer 403 can be formed by a local oxidation of silicon (LOCOS) method, a shallow trench isolation (STI) method, or the like.
[0407] 38 has a convex semiconductor region 447. A conductor 443 is provided to cover the side surface and top surface of the semiconductor region 447 with an insulator 445 interposed therebetween. Note that the conductor 443 covering the side surface of the semiconductor region 447 is not shown in FIG. A material that adjusts the work function can be used for the conductor 443.
[0408] A transistor having a convex semiconductor region such as the transistor 441 can be called a fin transistor because it utilizes the convex portion of a semiconductor substrate. Note that an insulator that is in contact with the upper portion of the convex portion and functions as a mask for forming the convex portion may be provided. Although FIG. 38 shows a structure in which the convex portion is formed by processing a part of the substrate 701, a semiconductor having a convex portion may be formed by processing an SOI substrate.
[0409] 38 is just an example, and the transistor 441 is not limited to this configuration and may have an appropriate configuration depending on the circuit configuration, the operation method of the circuit, etc. For example, the transistor 441 may be a planar transistor.
[0410] <<Transistor 601>> The transistor 601 can have a structure similar to that of the transistor 441.
[0411] <<Insulator 405, Insulator 407, Insulator 409, Insulator 411>> In addition to the element isolation layer 403, the transistor 441, and the transistor 601, the insulators 405, 407, 409, and 411 are provided over the substrate 701. A conductor 451 is embedded in the insulator 405, the insulator 407, the insulator 409, and the insulator 411. Here, the height of the top surface of the conductor 451 can be made approximately the same as the height of the top surface of the insulator 411.
[0412] The insulators 405, 407, 409, and 411 each function as an interlayer film and may also function as a planarization film that covers the uneven shapes below each of them.
[0413] <<Insulator 421, Insulator 214, Insulator 216>> The insulator 421 and the insulator 214 are provided over the conductor 451 and the insulator 411. The conductor 453 is embedded in the insulator 421 and the insulator 214. Here, the height of the top surface of the conductor 453 and the height of the top surface of the insulator 214 can be made approximately the same.
[0414] An insulator 216 is provided over the conductor 453 and the insulator 214. A conductor 455 is embedded in the insulator 216. Here, the height of the top surface of the conductor 455 and the height of the top surface of the insulator 216 can be made approximately the same.
[0415] <<Insulator 222, Insulator 224, Insulator 254, Insulator 280, Insulator 274, Insulator 281>> The insulators 222, 224, 254, 280, 274, and 281 are provided over the conductor 455 and the insulator 216.
[0416] Conductor 305 is embedded in insulator 222, insulator 224, insulator 254, insulator 280, insulator 274, and insulator 281. Here, the height of the top surface of conductor 305 and the height of the top surface of insulator 281 can be made approximately the same.
[0417] The insulators 421, 214, 280, 274, and 281 function as interlayer films and may also function as planarization films that cover the uneven shapes below them.
[0418] <<Insulator 361 >> The insulator 361 is provided over the conductor 305 and the insulator 281 .
[0419] <<Transistor 441>> As shown in Figure 38, the low-resistance region 449b, which functions as the other of the source region and drain region of the transistor 441, is electrically connected to the FPC 716 via the conductor 451, the conductor 453, the conductor 455, the conductor 305, the conductor 317, the conductor 337, the conductor 347, the conductor 353, the conductor 355, the conductor 357, the connection electrode 760, and the anisotropic conductor 780.
[0420] 39 is a cross-sectional view showing a structural example of a display device 10. The display device 10 includes a substrate 701B and a substrate 705, and the substrate 701B and the substrate 705 are bonded to each other with a sealing material 712. The display device 10 shown in FIG. 39 differs from the display device 10 shown in FIG. 38 in that a transistor 750 has a similar structure to the transistor 441 and that the substrate 701B and the substrate 701 are bonded to each other with an adhesive layer 459.
[0421] <<Adhesive Layer 459>> An adhesive layer 459 is provided on the insulator 216. A bump 458 is embedded in the adhesive layer 459. The adhesive layer 459 bonds the insulator 216 and the substrate 701B. Furthermore, the lower surface of the bump 458 contacts the conductor 455, and the upper surface of the bump 458 contacts the conductor 305, electrically connecting the conductor 455 and the conductor 305.
[0422] <<Insulator 405B, Insulator 280, Insulator 274, Insulator 281>> In addition to the element isolation layer 403B and the transistor 750, the insulator 405B, the insulator 280, the insulator 274, and the insulator 281 are provided over the substrate 701B. The conductor 305 is embedded in the insulator 405B, the insulator 280, the insulator 274, and the insulator 281. Here, the height of the top surface of the conductor 305 and the height of the top surface of the insulator 281 can be made approximately the same.
[0423] The insulator 405B, the insulator 280, the insulator 274, and the insulator 281 function as interlayer films and may also function as planarizing films that cover the uneven shapes below them.
[0424] <Configuration Example 5 of Display Device> The display device 10 illustrated in FIG. 40 is different from the display device 10 illustrated in FIG. 38 mainly in that OS transistors 602 and 603 are included instead of the transistors 441 and 601. An OS transistor can be used as the transistor 750. That is, the display device 10 illustrated in FIG. 40 includes stacked OS transistors. Note that FIG. 40 illustrates an example in which the transistors 602 and 603 are provided over a substrate 701. As described above, the substrate 701 can be a single-crystal semiconductor substrate such as a single-crystal silicon substrate or another semiconductor substrate. Various insulating substrates such as a glass substrate or a sapphire substrate can also be used as the substrate 701.
[0425] <Insulator 613 and Insulator 614> The insulator 613 and the insulator 614 are provided over the substrate 701, and the transistor 602 and the transistor 603 are provided over the insulator 614. Note that a transistor or the like may be provided between the substrate 701 and the insulator 613. For example, transistors having structures similar to those of the transistor 441 and the transistor 601 shown in FIG. 38 may be provided between the substrate 701 and the insulator 613.
[0426] <<Transistor 602 and Transistor 603>> The transistor 602 and the transistor 603 can be the transistors provided in the layer 20 described in Embodiment 3.
[0427] The transistors 602 and 603 can have a structure similar to that of the transistor 750. Note that the transistors 602 and 603 may be OS transistors having a different structure from that of the transistor 750.
[0428] <<Insulators 616, 622, 624, 654, 680, 674, and 681>> In addition to the transistors 602 and 603, the insulators 616, 622, 624, 654, 680, 674, and 681 are provided over the insulator 614. The conductor 461 is embedded in the insulators 654, 680, 674, and 681. Here, the height of the top surface of the conductor 461 can be made approximately the same as the height of the top surface of the insulator 681.
[0429] <<Insulator 501>> The insulator 501 is provided over the conductor 461 and the insulator 681. The conductor 463 is embedded in the insulator 501. Here, the height of the top surface of the conductor 463 and the height of the top surface of the insulator 501 can be made approximately the same.
[0430] The insulators 421 and 214 are provided over the conductor 463 and the insulator 501. The conductor 453 is embedded in the insulator 421 and the insulator 214. Here, the height of the top surface of the conductor 453 and the height of the top surface of the insulator 214 can be made approximately the same.
[0431] As shown in Figure 40, one of the source and drain of transistor 602 is electrically connected to FPC 716 via conductor 461, conductor 463, conductor 453, conductor 455, conductor 305, conductor 317, conductor 337, conductor 347, conductor 353, conductor 355, conductor 357, connection electrode 760, and anisotropic conductor 780.
[0432] Conductor 305 is embedded in insulator 222, insulator 224, insulator 254, insulator 280, insulator 274, and insulator 281. Here, the height of the top surface of conductor 305 and the height of the top surface of insulator 281 can be made approximately the same.
[0433] The insulators 613, 614, 680, 674, 681, and 501 function as interlayer films and may also function as planarizing films that cover the uneven shapes below them.
[0434] 40 , the display device 10 can have a narrower frame and be smaller, and all of the transistors included in the display device 10 can be OS transistors. This allows, for example, the transistors provided in the layer 20 and the transistors provided in the layer 30 described in Embodiment 3 to be manufactured using the same device. Therefore, the manufacturing cost of the display device 10 can be reduced, and the display device 10 can be manufactured at a low price.
[0435] 41 is a cross-sectional view illustrating a structural example of the display device 10. The display device 10 mainly differs from the display device 10 illustrated in FIG. 38 in that a layer including a transistor 800 is provided between a layer including a transistor 750 and a layer including a transistor 601 and a transistor 441.
[0436] 41 , the layer 20 described in Embodiment 3 can be formed from a layer including the transistors 601 and 441 and a layer including the transistor 800. The transistor 750 can be the transistor provided in the layer 30 described in Embodiment 3.
[0437] <<Insulator 821, Insulator 814>> The insulator 821 and the insulator 814 are provided over the conductor 451 and the insulator 411. The conductor 853 is embedded in the insulator 821 and the insulator 814. Here, the height of the top surface of the conductor 853 and the height of the top surface of the insulator 814 can be made approximately the same.
[0438] <<Insulator 816>> An insulator 816 is provided over the conductor 853 and the insulator 814. A conductor 855 is embedded in the insulator 816. Here, the height of the top surface of the conductor 855 and the height of the top surface of the insulator 816 can be made approximately the same.
[0439] <<Insulators 822, 824, 854, 880, 874, and 881>> Insulators 822, 824, 854, 880, 874, and 881 are provided on the conductor 855 and the insulator 816. The conductor 805 is embedded in the insulators 822, 824, 854, 880, 874, and 881. Here, the height of the top surface of the conductor 805 and the height of the top surface of the insulator 881 can be made approximately the same.
[0440] The insulator 421 and the insulator 214 are provided over the conductor 817 and the insulator 881 .
[0441] As shown in Figure 41, the low resistance region 449b, which functions as the other of the source region and drain region of the transistor 441, is electrically connected to the FPC 716 via conductor 451, conductor 853, conductor 855, conductor 805, conductor 817, conductor 453, conductor 455, conductor 305, conductor 317, conductor 337, conductor 347, conductor 353, conductor 355, conductor 357, connection electrode 760, and anisotropic conductor 780.
[0442] <<Transistor 800>> The transistor 800 is provided over the insulator 814. The transistor 800 can be the transistor provided in the layer 20 described in Embodiment 3. The transistor 800 is preferably an OS transistor. For example, the transistor 800 can be a transistor provided in the backup circuit 82.
[0443] Conductors 801a and 801b are embedded in the insulators 854, 880, 874, and 881. The conductor 801a is electrically connected to one of the source and the drain of the transistor 800, and the conductor 801b is electrically connected to the other of the source and the drain of the transistor 800. Here, the height of the top surfaces of the conductors 801a and 801b can be made approximately the same as the height of the top surface of the insulator 881.
[0444] <<Transistor 750>> The transistor 750 can be the transistor provided in the layer 30 described in Embodiment 3. For example, the transistor 750 can be a transistor provided in the pixel circuit 62. The transistor 750 is preferably an OS transistor.
[0445] Insulator 405, insulator 407, insulator 409, insulator 411, insulator 821, insulator 814, insulator 880, insulator 874, insulator 881, insulator 421, insulator 214, insulator 280, insulator 274, insulator 281, insulator 361, and insulator 363 function as interlayer films and may also function as planarizing films that cover the uneven shapes below each other.
[0446] 41 shows an example in which a conductor 801a, a conductor 801b, and a conductor 805 are formed in the same layer. Also shown is an example in which a conductor 811, a conductor 813, and a conductor 817 are formed in the same layer.
[0447] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.
[0448] Embodiment 5 In this embodiment, a transistor that can be used in a display device that is one embodiment of the present invention will be described.
[0449] 42A, 42B, and 42C are a top view and a cross-sectional view of a transistor 200A that can be used in a display device of one embodiment of the present invention and a periphery of the transistor 200A. The transistor 200A can be applied to the display device of one embodiment of the present invention.
[0450] FIG. 42A is a top view of the transistor 200A. Also, FIGS. 42B and 42C are cross-sectional views of the transistor 200A. Here, FIG. 42B is a cross-sectional view of the portion indicated by the dashed dotted line A1-A2 in FIG. 42A , and is also a cross-sectional view of the transistor 200A in the channel length direction. Also, FIG. 42C is a cross-sectional view of the portion indicated by the dashed dotted line A3-A4 in FIG. 42A , and is also a cross-sectional view of the transistor 200A in the channel width direction. Note that some elements are omitted from the top view in FIG. 42A for clarity.
[0451] As shown in FIG. 42 , the transistor 200A has a metal oxide 230a arranged on a substrate (not shown), a metal oxide 230b arranged on the metal oxide 230a, a conductor 242a and a conductor 242b arranged spaced apart from each other on the metal oxide 230b, an insulator 280 arranged on the conductors 242a and 242b and having an opening formed between the conductors 242a and 242b, a conductor 260 arranged in the opening, an insulator 250 arranged among the metal oxide 230b, the conductors 242a, the conductors 242b, the insulator 280, and the conductor 260, and a metal oxide 230c arranged among the metal oxide 230b, the conductors 242a, the conductors 242b, the insulator 280, and the insulator 250. 42B and 42C , it is preferable that the top surface of the conductor 260 approximately coincides with the top surfaces of the insulators 250, 254, metal oxide 230c, and 280. Note that, hereinafter, the metal oxides 230a, 230b, and 230c may be collectively referred to as the metal oxides 230. Furthermore, the conductors 242a and 242b may be collectively referred to as the conductors 242.
[0452] 42, the side surfaces of the conductors 242a and 242b facing the conductor 260 have a substantially vertical shape. Note that the transistor 200A shown in FIG. 42 is not limited to this, and the angle formed between the side surface and the bottom surface of the conductors 242a and 242b may be 10° to 80°, preferably 30° to 60°. Furthermore, the opposing side surfaces of the conductors 242a and 242b may have multiple surfaces.
[0453] 42, it is preferable that an insulator 254 be disposed between the insulator 224, the metal oxide 230a, the metal oxide 230b, the conductor 242a, the conductor 242b, and the metal oxide 230c and the insulator 280. Here, it is preferable that the insulator 254 be in contact with the side surface of the metal oxide 230c, the top and side surfaces of the conductor 242a, the top and side surfaces of the conductor 242b, the side surfaces of the metal oxide 230a and the metal oxide 230b, and the top surface of the insulator 224, as shown in FIGS.
[0454] Although the transistor 200A has a three-layer structure of the metal oxide 230a, the metal oxide 230b, and the metal oxide 230c in and around a region where a channel is formed (hereinafter also referred to as a channel formation region), the present invention is not limited to this. For example, a two-layer structure of the metal oxide 230b and the metal oxide 230c or a stacked structure of four or more layers may be provided. Furthermore, the transistor 200A has a two-layer structure of the conductor 260, but the present invention is not limited to this. For example, the conductor 260 may have a single-layer structure or a stacked structure of three or more layers. Furthermore, each of the metal oxide 230a, the metal oxide 230b, and the metal oxide 230c may have a stacked structure of two or more layers.
[0455] For example, when metal oxide 230c has a layered structure consisting of a first metal oxide and a second metal oxide on the first metal oxide, it is preferable that the first metal oxide has a composition similar to that of metal oxide 230b, and the second metal oxide has a composition similar to that of metal oxide 230a.
[0456] Here, the conductor 260 functions as the gate electrode of the transistor, and the conductors 242a and 242b function as source and drain electrodes, respectively. As described above, the conductor 260 is formed so as to be embedded in the opening of the insulator 280 and in the region sandwiched between the conductors 242a and 242b. Here, the arrangements of the conductors 260, 242a, and 242b are selected in a self-aligned manner with respect to the opening of the insulator 280. That is, in the transistor 200A, the gate electrode can be arranged between the source and drain electrodes in a self-aligned manner. Therefore, the conductor 260 can be formed without providing an alignment margin, thereby reducing the area occupied by the transistor 200A. This allows for a high-resolution display device. Furthermore, the display device can have a narrow frame.
[0457] As shown in FIG. 42, the conductor 260 preferably has a conductor 260a provided inside the insulator 250 and a conductor 260b provided so as to be embedded inside the conductor 260a.
[0458] The transistor 200A preferably includes an insulator 214 disposed on a substrate (not shown), an insulator 216 disposed on the insulator 214, a conductor 205 disposed so as to be embedded in the insulator 216, an insulator 222 disposed on the insulator 216 and the conductor 205, and an insulator 224 disposed on the insulator 222. A metal oxide 230a is preferably disposed on the insulator 224.
[0459] An insulator 274 functioning as an interlayer film and an insulator 281 are preferably provided over the transistor 200A. Here, the insulator 274 is preferably provided in contact with top surfaces of the conductor 260, the insulator 250, the insulator 254, the metal oxide 230c, and the insulator 280.
[0460] It is preferable that the insulators 222, 254, and 274 have the function of suppressing the diffusion of at least one of hydrogen (e.g., hydrogen atoms, hydrogen molecules, etc.). For example, it is preferable that the insulators 222, 254, and 274 have lower hydrogen permeability than the insulators 224, 250, and 280. It is also preferable that the insulators 222 and 254 have the function of suppressing the diffusion of oxygen (e.g., at least one of oxygen atoms, oxygen molecules, etc.). For example, it is preferable that the insulators 222 and 254 have lower oxygen permeability than the insulators 224, 250, and 280.
[0461] Here, the insulator 224, the metal oxide 230, and the insulator 250 are separated by the insulators 280 and 281, and the insulators 254 and 274. Therefore, impurities such as hydrogen and excess oxygen contained in the insulators 280 and 281 can be prevented from being mixed into the insulators 224, the metal oxide 230a, the metal oxide 230b, and the insulator 250.
[0462] It is preferable that a conductor 240 (conductor 240a and conductor 240b) electrically connected to the transistor 200A and functioning as a plug be provided. Note that an insulator 241 (insulator 241a and insulator 241b) is provided in contact with the side surface of the conductor 240 functioning as a plug. That is, the insulator 241 is provided in contact with the inner walls of the openings of the insulators 254, 280, 274, and 281. Alternatively, a first conductor of the conductor 240 may be provided in contact with the side surface of the insulator 241, and a second conductor of the conductor 240 may be provided further inside. Here, the height of the top surface of the conductor 240 and the height of the insulator 281 can be made approximately the same. Note that, although the transistor 200A illustrates a structure in which the first conductor of the conductor 240 and the second conductor of the conductor 240 are stacked, the present invention is not limited to this. For example, the conductor 240 may be configured to have a single layer or a laminated structure of three or more layers. When the structure has a laminated structure, the layers may be distinguished by assigning ordinal numbers to indicate the order of formation.
[0463] In the transistor 200A, a metal oxide that functions as an oxide semiconductor (hereinafter also referred to as an oxide semiconductor) is preferably used for the metal oxide 230 (the metal oxide 230a, the metal oxide 230b, and the metal oxide 230c) including the channel formation region. For example, a metal oxide having a band gap of 2 eV or more, preferably 2.5 eV or more, is preferably used as the metal oxide that forms the channel formation region of the metal oxide 230.
[0464] The metal oxide preferably contains at least indium (In) or zinc (Zn). In particular, it is preferable that it contains indium (In) and zinc (Zn). Furthermore, it is preferable that it contains an element M in addition to these. The element M can be one or more of aluminum (Al), gallium (Ga), yttrium (Y), tin (Sn), boron (B), titanium (Ti), iron (Fe), nickel (Ni), germanium (Ge), zirconium (Zr), molybdenum (Mo), lanthanum (La), cerium (Ce), neodymium (Nd), hafnium (Hf), tantalum (Ta), tungsten (W), magnesium (Mg), or cobalt (Co). In particular, it is preferable that the element M is one or more of aluminum (Al), gallium (Ga), yttrium (Y), or tin (Sn). Furthermore, it is more preferable that the element M contains either or both of Ga and Sn.
[0465] 42B , the film thickness of the metal oxide 230b in the region that does not overlap with the conductor 242 may be thinner than the film thickness of the region that overlaps with the conductor 242. This is formed by removing a portion of the upper surface of the metal oxide 230b when forming the conductors 242a and 242b. When a conductive film that will become the conductor 242 is formed on the upper surface of the metal oxide 230b, a low-resistance region may be formed near the interface with the conductive film. In this way, by removing the low-resistance region located between the conductors 242a and 242b on the upper surface of the metal oxide 230b, it is possible to prevent a channel from being formed in that region.
[0466] According to one embodiment of the present invention, a display device having high definition and a small transistor can be provided. Alternatively, a display device having high luminance and a transistor with high on-state current can be provided. Alternatively, a display device having high-speed operation and a transistor with stable electrical characteristics can be provided. Alternatively, a display device having low power consumption and a transistor with low off-state current can be provided.
[0467] The detailed structure of the transistor 200A that can be used in the display device of one embodiment of the present invention will be described.
[0468] The conductor 205 is arranged to have a region overlapping with the metal oxide 230 and the conductor 260. The conductor 205 is preferably embedded in the insulator 216.
[0469] The conductor 205 includes conductor 205a, conductor 205b, and conductor 205c. The conductor 205a is provided in contact with the bottom surface and sidewall of an opening provided in the insulator 216. The conductor 205b is provided so as to be embedded in a recess formed in the conductor 205a. Here, the top surface of the conductor 205b is lower than the top surface of the conductor 205a and the top surface of the insulator 216. The conductor 205c is provided in contact with the top surface of the conductor 205b and the side surface of the conductor 205a. Here, the height of the top surface of the conductor 205c is approximately the same as the height of the top surface of the conductor 205a and the height of the top surface of the insulator 216. In other words, the conductor 205b is configured to be enclosed by the conductors 205a and 205c.
[0470] The conductors 205a and 205c are preferably made of a conductive material that has a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, nitrogen atoms, nitrogen molecules, nitrogen oxide molecules (NO, NO, NO, etc.), copper atoms, etc. Alternatively, it is preferable to use a conductive material that has a function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.).
[0471] By using a conductive material that has the function of reducing hydrogen diffusion for the conductor 205a and the conductor 205c, it is possible to prevent impurities such as hydrogen contained in the conductor 205b from diffusing into the metal oxide 230 via the insulator 224 or the like. Furthermore, by using a conductive material that has the function of suppressing oxygen diffusion for the conductor 205a and the conductor 205c, it is possible to prevent the conductor 205b from being oxidized and its conductivity from decreasing. Examples of conductive materials that have the function of suppressing oxygen diffusion include titanium, titanium nitride, tantalum, tantalum nitride, ruthenium, and ruthenium oxide. Therefore, the conductor 205a may be formed as a single layer or a multilayer structure using the above-mentioned conductive materials. For example, the conductor 205a may be made of titanium nitride.
[0472] The conductor 205b is preferably made of a conductive material containing tungsten, copper, or aluminum as a main component, for example, tungsten.
[0473] Here, the conductor 260 may function as a first gate (also referred to as a top gate) electrode. The conductor 205 may function as a second gate (also referred to as a bottom gate) electrode. In this case, the potential applied to the conductor 205 may be changed independently of the potential applied to the conductor 260, thereby controlling the V th In particular, applying a negative potential to the conductor 205 can control the V th Therefore, when a negative potential is applied to the conductor 205, the drain current when the potential applied to the conductor 260 is 0 V can be made smaller than when no negative potential is applied.
[0474] The conductor 205 is preferably provided to be larger than the channel formation region in the metal oxide 230. In particular, as shown in Fig. 42C, the conductor 205 preferably extends also in a region outside the end portion intersecting with the channel width direction of the metal oxide 230. In other words, outside the side surface of the metal oxide 230 in the channel width direction, the conductor 205 and the conductor 260 preferably overlap with each other via an insulator.
[0475] With the above structure, the channel formation region of the metal oxide 230 can be electrically surrounded by the electric field of the conductor 260 that functions as a first gate electrode and the electric field of the conductor 205 that functions as a second gate electrode.
[0476] 42C, the conductor 205 is extended to function as wiring. However, the present invention is not limited to this, and a conductor functioning as wiring may be provided below the conductor 205.
[0477] The insulator 214 preferably functions as a barrier insulating film that prevents impurities such as water or hydrogen from entering the transistor 200A from the substrate side. Therefore, the insulator 214 prevents hydrogen atoms, hydrogen molecules, water molecules, nitrogen atoms, nitrogen molecules, and nitrogen oxide molecules (N 2 O, NO, NO 2 It is preferable to use an insulating material that has a function of suppressing the diffusion of impurities such as copper atoms (i.e., copper atoms are less likely to penetrate the impurities), or that has a function of suppressing the diffusion of oxygen (e.g., at least one of oxygen atoms, oxygen molecules, etc.) (i.e., oxygen is less likely to penetrate the insulating material).
[0478] For example, it is preferable to use aluminum oxide, silicon nitride, or the like as the insulator 214. This can prevent impurities such as water or hydrogen from diffusing from the substrate side of the insulator 214 to the transistor 200A side. Alternatively, it can prevent oxygen contained in the insulator 224 or the like from diffusing toward the substrate side of the insulator 214.
[0479] The insulators 216, 280, and 281, which function as interlayer films, preferably have a lower dielectric constant than the insulator 214. Using a material with a low dielectric constant as the interlayer film can reduce parasitic capacitance between wirings. For example, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide to which fluorine has been added, silicon oxide to which carbon has been added, silicon oxide to which carbon and nitrogen have been added, silicon oxide having vacancies, or the like can be used as appropriate for the insulators 216, 280, and 281.
[0480] The insulators 222 and 224 function as gate insulators.
[0481] Here, the insulator 224 in contact with the metal oxide 230 preferably releases oxygen upon heating. In this specification, oxygen released upon heating is sometimes referred to as excess oxygen. For example, the insulator 224 may be made of silicon oxide, silicon oxynitride, or the like as appropriate. By providing an insulator containing oxygen in contact with the metal oxide 230, oxygen vacancies in the metal oxide 230 can be reduced, and the reliability of the transistor 200A can be improved.
[0482] Specifically, an oxide material from which some oxygen is released by heating is preferably used as the insulator 224. The oxide from which oxygen is released by heating is an oxide from which the amount of released oxygen converted into oxygen atoms is 1.0×10 in thermal desorption spectroscopy (TDS) analysis. 18 atoms / cm 3 or more, preferably 1.0 × 10 19 atoms / cm 3 More preferably, 2.0 × 10 19 atoms / cm 3 or more, or 3.0 x 10 20 atoms / cm 3 The surface temperature of the film during the TDS analysis is preferably in the range of 100°C or higher and 700°C or lower, or 100°C or higher and 400°C or lower.
[0483] 42C , the thickness of the region of insulator 224 that does not overlap with insulator 254 and metal oxide 230b may be thinner than the thickness of the other region. It is preferable that the thickness of the region of insulator 224 that does not overlap with insulator 254 and metal oxide 230b is a thickness that allows sufficient diffusion of the oxygen.
[0484] Like the insulator 214, the insulator 222 preferably functions as a barrier insulating film that prevents impurities such as water or hydrogen from entering the transistor 200A from the substrate side. For example, the insulator 222 preferably has lower hydrogen permeability than the insulator 224. By surrounding the insulator 224, the metal oxide 230, the insulator 250, etc. with the insulators 222, 254, and 274, impurities such as water or hydrogen can be prevented from entering the transistor 200A from the outside.
[0485] Furthermore, it is preferable that the insulator 222 has a function of suppressing the diffusion of oxygen (e.g., at least one of oxygen atoms, oxygen molecules, etc.) (i.e., the oxygen is less likely to permeate). For example, it is preferable that the insulator 222 has lower oxygen permeability than the insulator 224. The insulator 222 has a function of suppressing the diffusion of oxygen or impurities, which is preferable because it can reduce the diffusion of oxygen contained in the metal oxide 230 toward the substrate side. Furthermore, it can suppress the reaction of the conductor 205 with oxygen contained in the insulator 224 or the metal oxide 230.
[0486] The insulator 222 may be an insulator containing an oxide of one or both of insulating materials, such as aluminum and hafnium. Examples of the insulator containing an oxide of one or both of aluminum and hafnium include aluminum oxide, hafnium oxide, and oxide containing aluminum and hafnium (hafnium aluminate). When the insulator 222 is formed using such a material, the insulator 222 functions as a layer that suppresses oxygen release from the metal oxide 230 or the intrusion of impurities such as hydrogen into the metal oxide 230 from the periphery of the transistor 200A.
[0487] Alternatively, for example, aluminum oxide, bismuth oxide, germanium oxide, niobium oxide, silicon oxide, titanium oxide, tungsten oxide, yttrium oxide, or zirconium oxide may be added to these insulators. Alternatively, these insulators may be nitrided. Silicon oxide, silicon oxynitride, or silicon nitride may be stacked on the above insulators.
[0488] The insulator 222 may be made of, for example, aluminum oxide, hafnium oxide, tantalum oxide, zirconium oxide, lead zirconate titanate (PZT), or strontium titanate (SrTiO 3 ) or (Ba,Sr)TiO 3 Insulators containing so-called high-k materials such as BST may be used in a single layer or a multilayer configuration. As transistors become smaller and more highly integrated, problems such as leakage current may occur due to thinner gate insulators. By using a high-k material as the insulator that functions as the gate insulator, it is possible to reduce the gate potential during transistor operation while maintaining the physical film thickness.
[0489] The insulator 222 and the insulator 224 may have a stacked structure of two or more layers. In this case, the stacked structures are not limited to those made of the same material, and may be those made of different materials. For example, an insulator similar to the insulator 224 may be provided below the insulator 222.
[0490] The metal oxide 230 includes a metal oxide 230a, a metal oxide 230b on the metal oxide 230a, and a metal oxide 230c on the metal oxide 230b. By providing the metal oxide 230a below the metal oxide 230b, it is possible to suppress the diffusion of impurities from structures formed below the metal oxide 230a to the metal oxide 230b. Furthermore, by providing the metal oxide 230c on the metal oxide 230b, it is possible to suppress the diffusion of impurities from structures formed above the metal oxide 230c to the metal oxide 230b.
[0491] The metal oxide 230 preferably has a stacked structure of multiple oxide layers with different atomic ratios of each metal atom. For example, when the metal oxide 230 contains at least indium (In) and the element M, the ratio of the number of atoms of the element M contained in the metal oxide 230a to the number of atoms of all elements constituting the metal oxide 230a is preferably higher than the ratio of the number of atoms of the element M contained in the metal oxide 230b to the number of atoms of all elements constituting the metal oxide 230b. Furthermore, the atomic ratio of the element M contained in the metal oxide 230a to In is preferably higher than the atomic ratio of the element M contained in the metal oxide 230b to In. Here, the metal oxide 230c can be the same as the metal oxide 230a or the metal oxide 230b.
[0492] The energy of the conduction band minimum of the metal oxide 230a and the metal oxide 230c is preferably higher than the energy of the conduction band minimum of the metal oxide 230b. In other words, the electron affinity of the metal oxide 230a and the metal oxide 230c is preferably lower than the electron affinity of the metal oxide 230b. In this case, the metal oxide 230c is preferably a metal oxide that can be used for the metal oxide 230a. Specifically, the ratio of the number of atoms of the element M contained in the metal oxide 230c to the number of atoms of all elements constituting the metal oxide 230c is preferably higher than the ratio of the number of atoms of the element M contained in the metal oxide 230b to the number of atoms of all elements constituting the metal oxide 230b. Furthermore, the atomic ratio of the element M contained in the metal oxide 230c to In is preferably higher than the atomic ratio of the element M contained in the metal oxide 230c to In.
[0493] Here, the energy level of the conduction band minimum changes smoothly at the junction between the metal oxide 230a, the metal oxide 230b, and the metal oxide 230c. In other words, the energy level of the conduction band minimum at the junction between the metal oxide 230a, the metal oxide 230b, and the metal oxide 230c changes continuously or forms a continuous junction. To achieve this, it is advisable to reduce the defect level density of the mixed layer formed at the interface between the metal oxide 230a and the metal oxide 230b and the interface between the metal oxide 230b and the metal oxide 230c.
[0494] Specifically, the metal oxide 230a and the metal oxide 230b, and the metal oxide 230b and the metal oxide 230c, have a common element other than oxygen (as a main component), thereby forming a mixed layer with a low defect level density. For example, when the metal oxide 230b is an In—Ga—Zn oxide, the metal oxide 230a and the metal oxide 230c may be made of an In—Ga—Zn oxide, a Ga—Zn oxide, gallium oxide, or the like. The metal oxide 230c may also have a stacked structure. For example, a stacked structure of an In—Ga—Zn oxide and a Ga—Zn oxide on the In—Ga—Zn oxide, or a stacked structure of an In—Ga—Zn oxide and a gallium oxide on the In—Ga—Zn oxide, may be used. In other words, a stacked structure of an In—Ga—Zn oxide and an oxide not containing In may be used as the metal oxide 230c.
[0495] Specifically, the metal oxide 230a may have an atomic ratio of In:Ga:Zn=1:3:4 or 1:1:0.5. The metal oxide 230b may have an atomic ratio of In:Ga:Zn=4:2:3 or 3:1:2. The metal oxide 230c may have an atomic ratio of In:Ga:Zn=1:3:4, In:Ga:Zn=4:2:3, Ga:Zn=2:1, or Ga:Zn=2:5. Specific examples of the metal oxide 230c having a stacked structure include a stacked structure of In:Ga:Zn=4:2:3 [atomic ratio] and Ga:Zn=2:1 [atomic ratio], a stacked structure of In:Ga:Zn=4:2:3 [atomic ratio] and Ga:Zn=2:5 [atomic ratio], and a stacked structure of In:Ga:Zn=4:2:3 [atomic ratio] and gallium oxide.
[0496] In this case, the main carrier path is the metal oxide 230b. By configuring the metal oxide 230a and the metal oxide 230c as described above, the defect state density at the interface between the metal oxide 230a and the metal oxide 230b and at the interface between the metal oxide 230b and the metal oxide 230c can be reduced. This reduces the effect of interface scattering on carrier conduction, allowing the transistor 200A to achieve a high on-state current and high frequency characteristics. Note that when the metal oxide 230c has a stacked structure, in addition to the effect of reducing the defect state density at the interface between the metal oxide 230b and the metal oxide 230c, it is expected that the diffusion of constituent elements of the metal oxide 230c toward the insulator 250 can be suppressed. More specifically, by configuring the metal oxide 230c as a stacked structure and positioning an oxide not containing In above the stacked structure, it is possible to suppress In that may diffuse toward the insulator 250. The insulator 250 functions as a gate insulator, and diffusion of In can result in poor transistor characteristics. Therefore, by forming the metal oxide 230c into a stacked structure, it is possible to provide a highly reliable display device.
[0497] Conductors 242 (conductors 242a and 242b) functioning as a source electrode and a drain electrode are provided on the metal oxide 230b. The conductor 242 is preferably a metal element selected from aluminum, chromium, copper, silver, gold, platinum, tantalum, nickel, titanium, molybdenum, tungsten, hafnium, vanadium, niobium, manganese, magnesium, zirconium, beryllium, indium, ruthenium, iridium, strontium, or lanthanum, or an alloy containing any of the above metal elements, or an alloy combining any of the above metal elements. For example, tantalum nitride, titanium nitride, tungsten, a nitride containing titanium and aluminum, a nitride containing tantalum and aluminum, ruthenium oxide, ruthenium nitride, an oxide containing strontium and ruthenium, or an oxide containing lanthanum and nickel is preferably used. In addition, tantalum nitride, titanium nitride, nitrides containing titanium and aluminum, nitrides containing tantalum and aluminum, ruthenium oxide, ruthenium nitride, oxides containing strontium and ruthenium, and oxides containing lanthanum and nickel are preferred because they are conductive materials that are resistant to oxidation or materials that maintain their conductivity even when they absorb oxygen.
[0498] By providing the conductor 242 so as to be in contact with the metal oxide 230, the oxygen concentration may be reduced in the vicinity of the conductor 242 of the metal oxide 230. Furthermore, a metal compound layer containing the metal contained in the conductor 242 and components of the metal oxide 230 may be formed in the vicinity of the conductor 242 of the metal oxide 230. In such a case, the carrier density increases in the region of the metal oxide 230 in the vicinity of the conductor 242, and this region becomes a low-resistance region.
[0499] Here, the region between the conductor 242a and the conductor 242b is formed to overlap the opening of the insulator 280. This allows the conductor 260 to be arranged in a self-aligned manner between the conductor 242a and the conductor 242b.
[0500] The insulator 250 functions as a gate insulator. The insulator 250 is preferably disposed in contact with the upper surface of the metal oxide 230c. The insulator 250 can be made of silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide doped with fluorine, silicon oxide doped with carbon, silicon oxide doped with carbon and nitrogen, or silicon oxide having vacancies. Silicon oxide and silicon oxynitride are particularly preferred because they are stable against heat.
[0501] The insulator 250 preferably has a reduced concentration of impurities such as water or hydrogen, similar to the insulator 224. The thickness of the insulator 250 is preferably 1 nm or more and 20 nm or less.
[0502] A metal oxide may be provided between the insulator 250 and the conductor 260. The metal oxide preferably suppresses oxygen diffusion from the insulator 250 to the conductor 260. This makes it possible to suppress oxidation of the conductor 260 due to oxygen in the insulator 250.
[0503] The metal oxide may function as part of the gate insulator. Therefore, when silicon oxide or silicon oxynitride is used for the insulator 250, it is preferable to use a metal oxide that is a high-k material with a high dielectric constant. By forming the gate insulator into a stacked structure of the insulator 250 and the metal oxide, a stacked structure that is stable against heat and has a high dielectric constant can be obtained. Therefore, it is possible to reduce the gate potential applied during transistor operation while maintaining the physical thickness of the gate insulator. In addition, it is possible to reduce the equivalent oxide thickness (EOT) of the insulator that functions as the gate insulator.
[0504] Specifically, it is possible to use a metal oxide containing one or more selected from hafnium, aluminum, gallium, yttrium, zirconium, tungsten, titanium, tantalum, nickel, germanium, magnesium, etc. In particular, it is preferable to use an insulator containing an oxide of either or both of aluminum and hafnium, such as aluminum oxide, hafnium oxide, or an oxide containing aluminum and hafnium (hafnium aluminate).
[0505] Although the conductor 260 is shown as having a two-layer structure in FIG. 42, it may have a single-layer structure or a laminated structure of three or more layers.
[0506] The conductor 260a is a material containing the above-mentioned hydrogen atoms, hydrogen molecules, water molecules, nitrogen atoms, nitrogen molecules, and nitrogen oxide molecules (N 2 O, NO, NO 2 It is preferable to use a conductor that has a function of suppressing the diffusion of impurities such as copper atoms, etc. Alternatively, it is preferable to use a conductive material that has a function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.).
[0507] The conductor 260a has a function of suppressing oxygen diffusion, which can suppress a decrease in conductivity due to oxidation of the conductor 260b caused by oxygen contained in the insulator 250. As a conductive material having a function of suppressing oxygen diffusion, it is preferable to use, for example, tantalum, tantalum nitride, ruthenium, ruthenium oxide, or the like.
[0508] The conductor 260b is preferably made of a conductive material containing tungsten, copper, or aluminum as a main component. Furthermore, since the conductor 260 also functions as wiring, it is preferable to use a conductor with high conductivity. For example, a conductive material containing tungsten, copper, or aluminum as a main component can be used. Furthermore, the conductor 260b may have a layered structure, such as a layered structure of titanium or titanium nitride and the above-mentioned conductive material.
[0509] 42A and 42C , in a region of the metal oxide 230b that does not overlap with the conductor 242, in other words, in the channel formation region of the metal oxide 230, the side surface of the metal oxide 230 is arranged to be covered with the conductor 260. This makes it easier for the electric field of the conductor 260, which functions as the first gate electrode, to act on the side surface of the metal oxide 230. This increases the on-state current of the transistor 200A and improves its frequency characteristics.
[0510] Like the insulator 214, the insulator 254 preferably functions as a barrier insulating film that prevents impurities such as water or hydrogen from entering the transistor 200A from the insulator 280 side. For example, the insulator 254 preferably has lower hydrogen permeability than the insulator 224. Furthermore, as shown in FIGS. 42B and 42C , the insulator 254 preferably contacts the side surface of the metal oxide 230c, the top and side surfaces of the conductor 242a, the top and side surfaces of the conductor 242b, the side surfaces of the metal oxide 230a and the metal oxide 230b, and the top surface of the insulator 224. This structure prevents hydrogen contained in the insulator 280 from entering the metal oxide 230 from the top or side surfaces of the conductor 242a, the conductor 242b, the metal oxide 230a, the metal oxide 230b, and the insulator 224.
[0511] Furthermore, it is preferable that the insulator 254 has a function of suppressing the diffusion of oxygen (e.g., at least one of oxygen atoms, oxygen molecules, etc.) (i.e., the oxygen is less likely to permeate). For example, it is preferable that the insulator 254 has lower oxygen permeability than the insulator 280 or the insulator 224.
[0512] The insulator 254 is preferably formed by a sputtering method. By forming the insulator 254 by a sputtering method in an oxygen-containing atmosphere, oxygen can be added to the insulator 224 near a region in contact with the insulator 254. This allows oxygen to be supplied from this region into the metal oxide 230 through the insulator 224. The insulator 254 has a function of suppressing upward oxygen diffusion, thereby preventing oxygen from diffusing from the metal oxide 230 to the insulator 280. The insulator 222 has a function of suppressing downward oxygen diffusion, thereby preventing oxygen from diffusing from the metal oxide 230 toward the substrate. In this manner, oxygen is supplied to the channel formation region of the metal oxide 230. This reduces oxygen vacancies in the metal oxide 230 and suppresses the transistor from becoming normally on.
[0513] For example, an insulator containing an oxide of one or both of aluminum and hafnium may be formed as the insulator 254. Note that as the insulator containing an oxide of one or both of aluminum and hafnium, aluminum oxide, hafnium oxide, an oxide containing aluminum and hafnium (hafnium aluminate), or the like is preferably used.
[0514] The insulator 224, the insulator 250, and the metal oxide 230 are covered with the insulator 254, which has a barrier property against hydrogen, so that the insulator 280 is separated from the insulator 224, the metal oxide 230, and the insulator 250 by the insulator 254. This makes it possible to prevent impurities such as hydrogen from penetrating from the outside of the transistor 200A, thereby providing the transistor 200A with good electrical characteristics and reliability.
[0515] The insulator 280 is provided over the insulator 224, the metal oxide 230, and the conductor 242 with the insulator 254 interposed therebetween. For example, the insulator 280 preferably includes silicon oxide, silicon oxynitride, silicon nitride oxide, silicon oxide to which fluorine has been added, silicon oxide to which carbon has been added, silicon oxide to which carbon and nitrogen have been added, silicon oxide having vacancies, or the like. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, materials such as silicon oxide, silicon oxynitride, and silicon oxide having vacancies are preferable because they can easily form a region containing oxygen that is released by heating.
[0516] It is preferable that the concentration of impurities such as water or hydrogen is reduced in the insulator 280. The top surface of the insulator 280 may be flattened.
[0517] Similar to the insulator 214, the insulator 274 preferably functions as a barrier insulating film that prevents impurities such as water or hydrogen from entering the insulator 280 from above. As the insulator 274, for example, an insulator that can be used for the insulator 214, the insulator 254, etc. may be used.
[0518] An insulator 281 functioning as an interlayer film is preferably provided over the insulator 274. Like the insulator 224, the insulator 281 preferably has a reduced concentration of impurities such as water or hydrogen.
[0519] The conductor 240a and the conductor 240b are arranged in openings formed in the insulator 281, the insulator 274, the insulator 280, and the insulator 254. The conductor 240a and the conductor 240b are provided opposite each other with the conductor 260 interposed therebetween. Note that the height of the top surfaces of the conductor 240a and the conductor 240b may be flush with the top surface of the insulator 281.
[0520] Note that insulator 241a is provided in contact with the inner walls of the openings of insulators 281, 274, 280, and 254, and a first conductor of conductor 240a is formed in contact with the side surface of insulator 241a. Conductor 242a is located on at least a portion of the bottom of the openings, and conductor 240a is in contact with conductor 242a. Similarly, insulator 241b is provided in contact with the inner walls of the openings of insulators 281, 274, 280, and 254, and a first conductor of conductor 240b is formed in contact with the side surface of insulator 241b. Conductor 242b is located on at least a portion of the bottom of the openings, and conductor 240b is in contact with conductor 242b.
[0521] The conductors 240a and 240b are preferably made of a conductive material containing tungsten, copper, or aluminum as a main component. The conductors 240a and 240b may have a layered structure.
[0522] When the conductor 240 has a layered structure, it is preferable to use the above-mentioned conductors that have the function of suppressing the diffusion of impurities such as water or hydrogen for the conductors in contact with the metal oxide 230a, the metal oxide 230b, the conductor 242, the insulator 254, the insulator 280, the insulator 274, and the insulator 281. For example, it is preferable to use tantalum, tantalum nitride, titanium, titanium nitride, ruthenium, or ruthenium oxide. Furthermore, the conductive material that has the function of suppressing the diffusion of impurities such as water or hydrogen may be used in a single layer or a layered structure. Using such a conductive material can suppress the absorption of oxygen added to the insulator 280 by the conductors 240a and 240b. Furthermore, it is possible to suppress the intrusion of impurities such as water or hydrogen from layers above the insulator 281 into the metal oxide 230 through the conductors 240a and 240b.
[0523] The insulators 241a and 241b may be, for example, an insulator that can be used for the insulator 254. The insulators 241a and 241b are provided in contact with the insulator 254, and therefore can prevent impurities such as water or hydrogen from the insulator 280 from being mixed into the metal oxide 230 through the conductors 240a and 240b. Furthermore, oxygen contained in the insulator 280 can be prevented from being absorbed by the conductors 240a and 240b.
[0524] Although not shown, a conductor functioning as wiring may be disposed in contact with the upper surface of the conductor 240a and the upper surface of the conductor 240b. The conductor functioning as wiring is preferably made of a conductive material containing tungsten, copper, or aluminum as a main component. The conductor may also have a layered structure, for example, a layered structure of titanium or titanium nitride and the above-mentioned conductive material. The conductor may be formed so as to be embedded in an opening provided in an insulator.
[0525] <Constituent Materials of Transistor> Constituent materials that can be used for the transistor will be described.
[0526] [Substrate] The substrate on which the transistor 200A is formed may be, for example, an insulating substrate, a semiconductor substrate, or a conductive substrate. Examples of insulating substrates include glass substrates, quartz substrates, sapphire substrates, stabilized zirconia substrates (e.g., yttria-stabilized zirconia substrates), and resin substrates. Examples of semiconductor substrates include semiconductor substrates such as silicon and germanium, or compound semiconductor substrates made of silicon carbide, silicon germanium, gallium arsenide, indium phosphide, zinc oxide, and gallium oxide. Examples of semiconductor substrates include those having an insulating region within the semiconductor substrate, such as an SOI (Silicon-On-Insulator) substrate. Examples of conductive substrates include graphite substrates, metal substrates, alloy substrates, and conductive resin substrates. Examples of substrates include substrates having a metal nitride or a metal oxide. Examples of substrates include an insulating substrate with a conductor or semiconductor provided thereon, a semiconductor substrate with a conductor or insulator provided thereon, and a conductive substrate with a semiconductor or insulator provided thereon. Alternatively, a substrate provided with elements may be used. The elements provided on the substrate include a capacitor element, a resistor element, a switch element, a light-emitting element, a memory element, and the like.
[0527] [Insulator] Examples of insulators include oxides, nitrides, oxynitrides, nitride oxides, metal oxides, metal oxynitrides, and metal nitride oxides, which have insulating properties.
[0528] For example, as transistors become more miniaturized and highly integrated, problems such as leakage current may occur due to thinner gate insulators. Using a high-k material for the insulator that functions as the gate insulator allows for lower voltage operation of the transistor while maintaining the physical film thickness. On the other hand, using a material with a low dielectric constant for the insulator that functions as the interlayer film can reduce the parasitic capacitance that occurs between wiring. Therefore, it is advisable to select a material depending on the function of the insulator.
[0529] Examples of insulators with a high relative dielectric constant include gallium oxide, hafnium oxide, zirconium oxide, oxides containing aluminum and hafnium, oxynitrides containing aluminum and hafnium, oxides containing silicon and hafnium, oxynitrides containing silicon and hafnium, and nitrides containing silicon and hafnium.
[0530] Examples of insulators with a low dielectric constant include silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide doped with fluorine, silicon oxide doped with carbon, silicon oxide doped with carbon and nitrogen, silicon oxide having voids, and resin.
[0531] The electrical characteristics of a transistor including an oxide semiconductor can be stabilized by surrounding it with an insulator (such as the insulator 214, the insulator 222, the insulator 254, and the insulator 274) that has a function of suppressing the permeation of impurities such as hydrogen and oxygen. Examples of insulators that have a function of suppressing the permeation of impurities such as hydrogen and oxygen include, for example, a single-layer or stacked insulator containing boron, carbon, nitrogen, oxygen, fluorine, magnesium, aluminum, silicon, phosphorus, chlorine, argon, gallium, germanium, yttrium, zirconium, lanthanum, neodymium, hafnium, or tantalum. Specifically, examples of insulators that have a function of suppressing the permeation of impurities such as hydrogen and oxygen include metal oxides such as aluminum oxide, magnesium oxide, gallium oxide, germanium oxide, yttrium oxide, zirconium oxide, lanthanum oxide, neodymium oxide, hafnium oxide, and tantalum oxide; and metal nitrides such as aluminum nitride, aluminum titanium nitride, titanium nitride, silicon nitride oxide, and silicon nitride.
[0532] The insulator functioning as the gate insulator is preferably an insulator having a region containing oxygen that is released by heating. For example, by using a structure in which silicon oxide or silicon oxynitride having a region containing oxygen that is released by heating is in contact with the metal oxide 230, oxygen vacancies in the metal oxide 230 can be compensated for.
[0533] [Conductor] As the conductor, it is preferable to use a metal element selected from aluminum, chromium, copper, silver, gold, platinum, tantalum, nickel, titanium, molybdenum, tungsten, hafnium, vanadium, niobium, manganese, magnesium, zirconium, beryllium, indium, ruthenium, iridium, strontium, lanthanum, etc., or an alloy containing the above metal element as a component, or an alloy combining the above metal elements. For example, it is preferable to use tantalum nitride, titanium nitride, tungsten, nitrides containing titanium and aluminum, nitrides containing tantalum and aluminum, ruthenium oxide, ruthenium nitride, oxides containing strontium and ruthenium, oxides containing lanthanum and nickel, etc. Furthermore, tantalum nitride, titanium nitride, nitrides containing titanium and aluminum, nitrides containing tantalum and aluminum, ruthenium oxide, ruthenium nitride, oxides containing strontium and ruthenium, and oxides containing lanthanum and nickel are preferred because they are conductive materials that are resistant to oxidation or maintain conductivity even when absorbing oxygen. Furthermore, semiconductors with high electrical conductivity, such as polycrystalline silicon containing impurity elements such as phosphorus, and silicides such as nickel silicide may also be used.
[0534] A plurality of conductors formed from the above materials may be stacked. For example, a stacked structure may be formed by combining the above-mentioned material containing a metal element and a conductive material containing oxygen. A stacked structure may also be formed by combining the above-mentioned material containing a metal element and a conductive material containing nitrogen. A stacked structure may also be formed by combining the above-mentioned material containing a metal element, a conductive material containing oxygen, and a conductive material containing nitrogen.
[0535] When a metal oxide is used for the channel formation region of a transistor, a conductor functioning as a gate electrode preferably has a stacked structure of a combination of a material containing the metal element and a conductive material containing oxygen. In this case, the conductive material containing oxygen is preferably provided on the channel formation region side. By providing the conductive material containing oxygen on the channel formation region side, oxygen released from the conductive material is easily supplied to the channel formation region.
[0536] In particular, as a conductor functioning as a gate electrode, it is preferable to use a conductive material containing oxygen and a metal element contained in the metal oxide in which the channel is formed. Alternatively, a conductive material containing the above-mentioned metal element and nitrogen may be used. For example, a conductive material containing nitrogen, such as titanium nitride or tantalum nitride, may be used. Alternatively, indium tin oxide, indium oxide containing tungsten oxide, indium zinc oxide containing tungsten oxide, indium oxide containing titanium oxide, indium tin oxide containing titanium oxide, indium zinc oxide, or indium tin oxide doped with silicon may be used. Furthermore, indium gallium zinc oxide containing nitrogen may be used. By using such a material, hydrogen contained in the metal oxide in which the channel is formed may be captured. Alternatively, hydrogen introduced from an external insulator or the like may be captured.
[0537] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.
[0538] Embodiment 6 In this embodiment, a metal oxide (hereinafter also referred to as an oxide semiconductor) that can be used for the OS transistor described in the above embodiment will be described.
[0539] <Classification of Crystal Structures> First, classification of crystal structures in oxide semiconductors will be described with reference to Fig. 43A. Fig. 43A is a diagram illustrating classification of crystal structures of oxide semiconductors, typically IGZO (metal oxide containing In, Ga, and Zn).
[0540] As shown in FIG. 43A , oxide semiconductors are broadly classified into "amorphous," "crystalline," and "crystal." Furthermore, "amorphous" includes completely amorphous. Furthermore, "crystalline" includes c-axis-aligned crystalline (CAAC), nanocrystalline (nc), and cloud-aligned composite (CAC). The "crystalline" classification excludes single crystal, polycrystalline, and completely amorphous. Furthermore, "Crystal" includes single crystal and poly crystal.
[0541] The structure within the bold frame shown in Figure 43A is an intermediate state between "Amorphous" and "Crystal" and belongs to a new boundary region (New crystalline phase). In other words, this structure can be said to be completely different from the energetically unstable "Amorphous" or "Crystal."
[0542] The crystalline structure of the film or substrate can be evaluated using an X-ray diffraction (XRD) spectrum. Here, FIG. 43B shows an XRD spectrum obtained by GIXD (Grazing-Incident XRD) measurement of a CAAC-IGZO film classified as "Crystalline." The GIXD method is also called the thin-film method or the Seemann-Bohlin method. Hereinafter, the XRD spectrum obtained by GIXD measurement shown in FIG. 43B will be simply referred to as the XRD spectrum. The composition of the CAAC-IGZO film shown in FIG. 43B is approximately In:Ga:Zn = 4:2:3 [atomic ratio]. The thickness of the CAAC-IGZO film shown in FIG. 43B is 500 nm.
[0543] As shown in Figure 43B, a peak indicating clear crystallinity is detected in the XRD spectrum of the CAAC-IGZO film. Specifically, a peak indicating c-axis orientation is detected near 2θ = 31° in the XRD spectrum of the CAAC-IGZO film. Note that, as shown in Figure 43B, the peak near 2θ = 31° is asymmetric with respect to the angle at which the peak intensity is detected.
[0544] 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). The diffraction pattern of the CAAC-IGZO film is shown in FIG. 43C. FIG. 43C is a diffraction pattern observed by NBED, in which an electron beam is incident parallel to the substrate. The composition of the CAAC-IGZO film shown in FIG. 43C is near In:Ga:Zn = 4:2:3 [atomic ratio]. In addition, in nanobeam electron diffraction, electron beam diffraction is performed using a probe diameter of 1 nm.
[0545] As shown in FIG. 43C, multiple spots indicating c-axis orientation are observed in the diffraction pattern of the CAAC-IGZO film.
[0546] [Structure of Oxide Semiconductor] Note that oxide semiconductors may be classified differently from those shown in FIG. 43A when focusing on their crystal structures. 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.
[0547] Here, the above-mentioned CAAC-OS, nc-OS, and a-like OS will be described in detail.
[0548] [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.
[0549] 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.
[0550] 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 TEM image, for example.
[0551] 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, composition, and the like of the metal elements constituting the CAAC-OS.
[0552] 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).
[0553] 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 also have a pentagonal, heptagonal, or other lattice arrangement. In 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 CAAC-OS can tolerate distortion due to the lack of close-packed arrangement of oxygen atoms in the a-b plane and the change in interatomic bond distance caused by substitution of metal atoms.
[0554] 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.
[0555] 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 or defects (oxygen vacancies, etc.). 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.
[0556] [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.
[0557] [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.
[0558] [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.
[0559] [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.
[0560] 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.
[0561] 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.
[0562] 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 rephrased as a region whose main component is In. The second region can be rephrased as a region whose main component is Ga.
[0563] It should be noted that there are cases where a clear boundary between the first region and the second region cannot be observed.
[0564] 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.
[0565] 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). That is, a CAC-OS has a conductive function in a part of the material and an insulating function in a part of the material, and functions as a semiconductor as a whole. 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.
[0566] 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.
[0567] <Transistor Having Oxide Semiconductor> Next, a case where the oxide semiconductor is used for a transistor will be described.
[0568] By using the oxide semiconductor for a transistor, a transistor with high field-effect mobility and high reliability can be realized.
[0569] 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 10 cm −3 is less than 1×10 −9 cm −3That 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.
[0570] 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.
[0571] 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.
[0572] 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.
[0573] <Impurities> Here, the influence of each impurity in an oxide semiconductor will be described.
[0574] When an oxide semiconductor contains silicon or carbon, which is one of the 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 SIMS) are calculated to be 2×10 18 atoms / cm 3 Below 2 × 10, preferably 17 atoms / cm 3 The following applies.
[0575] 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:
[0576] 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:
[0577] 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 / cm 3 less than 1×1019 atoms / cm 3 less than 5×10 18 atoms / cm 3 less than 1×10 18 atoms / cm 3 Make it less than.
[0578] When an oxide semiconductor with sufficiently reduced impurities is used for a channel formation region of a transistor, stable electrical characteristics can be obtained.
[0579] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.
[0580] Embodiment 7 In this embodiment, an electronic device including a display device and a display system which are one embodiment of the present invention will be described.
[0581] FIG. 44A is a diagram showing the appearance of the head-mounted display 8200.
[0582] The head-mounted display 8200 includes a mounting portion 8201, a lens 8202, a main body 8203, a display portion 8204, and a cable 8205. The mounting portion 8201 has a built-in battery 8206.
[0583] A cable 8205 supplies power from a battery 8206 to the main body 8203. The main body 8203 is provided with a wireless receiver or the like, and can display an image corresponding to received image data or the like on a display portion 8204. In addition, a camera provided in the main body 8203 captures the movement of the user's eyeball or eyelid, and calculates the coordinates of the user's line of sight based on the information, thereby allowing the user's line of sight to be used as an input means.
[0584] The attachment unit 8201 may be provided with a plurality of electrodes at positions that come into contact with the user. The main body 8203 may have a function of recognizing the user's line of sight by detecting a current flowing through the electrodes in accordance with the movement of the user's eyeballs. The main body 8203 may also have a function of monitoring the user's pulse by detecting the current flowing through the electrodes. The attachment unit 8201 may also have various sensors such as a temperature sensor, a pressure sensor, and an acceleration sensor, and may have a function of displaying biological information of the user on the display unit 8204. The attachment unit 8201 may also detect the movement of the user's head, and change the image displayed on the display unit 8204 in accordance with the movement.
[0585] The display device of one embodiment of the present invention can be applied to the display portion 8204. This allows the power consumption of the head-mounted display 8200 to be reduced, and therefore the head-mounted display 8200 can be used continuously for a long period of time. Furthermore, by reducing the power consumption of the head-mounted display 8200, the battery 8206 can be made smaller and lighter, and therefore the head-mounted display 8200 can be made smaller and lighter. This reduces the burden on a user of the head-mounted display 8200, and the user can feel less fatigued.
[0586] 44B, 44C, and 44D are diagrams showing the external appearance of a head-mounted display 8300. The head-mounted display 8300 includes a housing 8301, a display portion 8302, a band-shaped fixture 8304, and a pair of lenses 8305. A battery 8306 is built into the housing 8301, and power can be supplied from the battery 8306 to the display portion 8302 and the like.
[0587] A user can view the display on the display portion 8302 through the lens 8305. Note that it is preferable to arrange the display portion 8302 in a curved manner. By arranging the display portion 8302 in a curved manner, a user can feel a high sense of presence. Note that although the configuration in which one display portion 8302 is provided has been illustrated in this embodiment, the present invention is not limited thereto. For example, two display portions 8302 may be provided. In this case, if one display portion is provided for one eye of the user, three-dimensional display using parallax or the like can be performed.
[0588] Note that the display device of one embodiment of the present invention can be applied to the display portion 8302. This allows the power consumption of the head-mounted display 8300 to be reduced, and therefore the head-mounted display 8300 can be used continuously for a long period of time. Furthermore, by reducing the power consumption of the head-mounted display 8300, the battery 8306 can be made smaller and lighter, and therefore the head-mounted display 8300 can be made smaller and lighter. This reduces the burden on a user of the head-mounted display 8300, and the user can feel less fatigue.
[0589] Next, an example of an electronic device different from the electronic device shown in FIGS. 44A to 44D is shown in FIGS. 45A and 45B.
[0590] The electronic device shown in Figures 45A and 45B has a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), a connection terminal 9006, a sensor 9007 (including a function to measure force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays), and a battery 9009.
[0591] The electronic devices shown in Figures 45A and 45B 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 connect to various computer networks using the wireless communication function, a function to send or receive various data using the wireless communication function, a function to read programs or data recorded on a recording medium and display them on a display unit, etc. Note that the functions that the electronic devices shown in Figures 45A and 45B can have are not limited to these, and they may have various other functions. Also, although not shown in Figures 45A and 45B, the electronic devices may be configured to have multiple display units. Furthermore, the electronic devices may be equipped with a camera or the like to capture still images, capture videos, save captured images to a recording medium (external or built-in to the camera), display captured images on a display unit, etc.
[0592] The electronic device shown in FIGS. 45A and 45B will be described in detail below.
[0593] FIG. 45A is a perspective view showing a mobile information terminal 9101. The mobile information terminal 9101 has one or more functions selected from, for example, a telephone, a notebook, an information viewing device, and the like. Specifically, it can be used as a smartphone. The mobile information terminal 9101 can display text or images on multiple surfaces. For example, three operation buttons 9050 (also referred to as operation icons or simply icons) can be displayed on one surface of the display unit 9001. Information 9051, indicated by a dashed rectangle, can be displayed on the other surface of the display unit 9001. Examples of the information 9051 include an indication of an incoming email, SNS (social networking service), or phone call, the title of the email or SNS, the name of the sender of the email or SNS, the date and time, the remaining battery level, and the strength of the antenna reception. Alternatively, the operation buttons 9050 or the like may be displayed in place of the information 9051.
[0594] The display device of one embodiment of the present invention can be applied to the portable information terminal 9101. This allows the power consumption of the portable information terminal 9101 to be reduced, and therefore the portable information terminal 9101 can be used continuously for a long period of time. Furthermore, by reducing the power consumption of the portable information terminal 9101, the battery 9009 can be made smaller and lighter, and therefore the portable information terminal 9101 can be made smaller and lighter. This allows the portable information terminal 9101 to be more portable.
[0595] FIG. 45B is a perspective view showing a wristwatch-type portable information terminal 9200. The portable information terminal 9200 can execute various applications such as mobile phone, e-mail, text browsing and creation, music playback, Internet communication, and computer games. The display surface of the display unit 9001 is curved, and display can be performed along the curved display surface. FIG. 45B shows an example in which time 9251, operation buttons 9252 (also referred to as operation icons or simply icons), and content 9253 are displayed on the display unit 9001. The content 9253 can be, for example, a video.
[0596] The portable information terminal 9200 is also capable of performing short-range wireless communication according to a communication standard. For example, hands-free conversation is also possible by mutual communication with a wirelessly enabled headset. The portable information terminal 9200 also has a connection terminal 9006, and can directly exchange data with another information terminal via a connector. Charging can also be performed via the connection terminal 9006. Note that charging may be performed by wireless power supply without using the connection terminal 9006.
[0597] The display device of one embodiment of the present invention can be applied to the portable information terminal 9200. This allows the power consumption of the portable information terminal 9200 to be reduced, and therefore the portable information terminal 9200 can be used continuously for a long period of time. Furthermore, by reducing the power consumption of the portable information terminal 9200, the battery 9009 can be made smaller and lighter, and therefore the portable information terminal 9200 can be made smaller and lighter. This allows the portable information terminal 9200 to be more portable.
[0598] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.
[0599] <Additional Notes Regarding the Description of the Present Specification, etc.> The following additional notes will be given regarding the above-described embodiments and the explanations of the respective configurations in the embodiments.
[0600] The configurations shown in each embodiment can be combined with the configurations shown in other embodiments as appropriate to form one aspect of the present invention. In addition, when multiple configuration examples are shown in one embodiment, the configuration examples can be combined as appropriate.
[0601] In addition, the content (or even a part of the content) described in one embodiment can be applied to, combined with, or replaced with another content (or even a part of the content) described in that embodiment, and / or the content (or even a part of the content) described in one or more other embodiments.
[0602] The contents described in the embodiments refer to the contents described in each embodiment using various figures or the contents described using text in the specification.
[0603] Furthermore, a figure (or even a part thereof) described in one embodiment can be combined with another part of that figure, another figure (or even a part thereof) described in that embodiment, and / or a figure (or even a part thereof) described in one or more other embodiments to form even more figures.
[0604] In addition, in the block diagrams in this specification, components are classified by function and shown as independent blocks. However, in actual circuits, it is difficult to separate components by function, and there may be cases where a single circuit is involved in multiple functions, or where a single function is involved across multiple circuits. Therefore, the blocks in the block diagrams are not limited to the components described in the specification, but may be rephrased appropriately depending on the situation.
[0605] In addition, in the drawings, the size, layer thickness, or region is shown at an arbitrary size for convenience of explanation. Therefore, it is not necessarily limited to the scale. Note that the drawings are shown schematically for clarity, and are not limited to the shapes or values shown in the drawings. For example, it is possible to include variations in signal, voltage, or current due to noise, or variations in signal, voltage, or current due to timing deviations.
[0606] In this specification and the like, when describing the connection relationship of a transistor, the terms "one of the source or drain" (or first electrode or first terminal) and "the other of the source or drain" (or second electrode or second terminal) are used. This is because the source and drain of a transistor vary depending on the structure or operating conditions of the transistor. Note that the names of the source and drain of a transistor can be appropriately changed to source (drain) terminal or source (drain) electrode, etc., depending on the situation.
[0607] Furthermore, the terms "electrode" and "wiring" used in this specification and the like do not limit the functionality of these components. For example, an "electrode" may be used as part of a "wiring," and vice versa. Furthermore, the terms "electrode" and "wiring" also include cases where multiple "electrodes" and "wirings" are integrally formed.
[0608] Furthermore, in this specification and the like, the terms voltage and potential can be interchanged as appropriate. Voltage refers to the potential difference from a reference potential. For example, if the reference potential is a ground voltage (earth voltage), then voltage can be interchanged with potential. Ground potential does not necessarily mean 0 V. Note that potential is relative, and the potential applied to wiring, etc. may change depending on the reference potential.
[0609] In this specification and the like, terms such as "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."
[0610] In this specification, a switch refers to a device that has a function of controlling whether a current flows by being in a conductive state (on state) or a non-conductive state (off state), or a device that has a function of selecting and switching a path for a current to flow.
[0611] In this specification, the channel length refers to, for example, in a top view of a transistor, a region where a semiconductor (or a portion in the semiconductor through which current flows when the transistor is on) and a gate overlap, or a distance between a source and a drain in a region where a channel is formed.
[0612] In this specification, the channel width refers to, for example, the length of the region where the semiconductor (or the portion in the semiconductor through which current flows when the transistor is on) and the gate electrode overlap, or the length of the portion where the source and drain face each other in the region where the channel is formed.
[0613] In this specification, "A and B are connected" includes not only a direct connection between A and B, but also an electrical connection between A and B. Here, "A and B are electrically connected" means that when an object having some kind of electrical effect exists between A and B, transmission of an electrical signal between A and B is possible.
[0614] CC: color conversion layer, C11: capacitance, C12: capacitance, COM1: conductive film, COM2: conductive film, COM2p: conductive film, FR1: period, FR2: period, G1: conductive film, G2: conductive film, G3: conductive film, G12: conductive film, G13: conductive film, GD: drive circuit, GL: gate line, GL2p: gate line, GL11: gate line, GL12: gate line, M11: transistor, N11: node, SD: drive circuit, SWm: switch, SW11: switch, SW12: switch, SW13: switch, SW2: switch, SW2p: switch, SW3p: switch, SW3q: switch switch, S1: conductive film, V0: wiring, V1: wiring, 10: display device, 10A: display device, 20: layer, 30: layer, 40: drive circuit, 41: gate driver, 42: source driver, 50: functional circuit, 51: CPU, 52: accelerator, 53: CPU core, 60: display unit, 61: pixel, 61D: pixel, 61N: pixel, 62: pixel circuit, 62B: pixel circuit, 62G: pixel circuit, 62R: pixel circuit, 70: light-emitting element, 80: flip-flop, 81: scan flip-flop, 82: backup circuit, 200A: transistor, 205: conductor, 205a: Conductor, 205b: Conductor, 205c: Conductor, 214: Insulator, 216: Insulator, 222: Insulator, 224: Insulator, 230: Metal oxide, 230a: Metal oxide, 230b: Metal oxide, 230c: Metal oxide, 231: Region, 240: Conductor, 240a: Conductor, 240b: Conductor, 241: Insulator, 241a: Insulator, 241b: Insulator, 242: Conductor, 242a: Conductor, 242b: Conductor, 250: Insulator, 254: Insulator, 260: Conductor, 260a: Conductor, 260b: Conductor, 274: Insulator, 280: Insulator, 281: Insulator, 3 01a: conductor, 301b: conductor, 305: conductor, 311: conductor, 313: conductor, 317: conductor, 321: lower electrode, 323: insulator, 325: upper electrode, 331: conductor, 333: conductor, 335: conductor, 337: conductor, 341: conductor, 343: conductor, 347: conductor, 351: conductor, 353: conductor, 355: conductor, 357: conductor, 361: insulator, 363: insulator, 403: element isolation layer, 403B: element isolation layer, 405: insulator, 405B: insulator, 407: insulator, 409: insulator, 411: insulator, 421: insulator,441: transistor, 443: conductor, 445: insulator, 447: semiconductor region, 449a: low resistance region, 449b: low resistance region, 451: conductor, 453: conductor, 455: conductor, 459: adhesive layer, 461: conductor, 463: conductor, 501: insulator, 520: functional layer, 530: pixel circuit, 541: pad, 542: pad, 543: conductive material, 550: light-emitting device, 601: transistor, 602: transistor, 603: transistor, 613: insulator, 614: insulator , 616: insulator, 622: insulator, 624: insulator, 654: insulator, 674: insulator, 680: insulator, 681: insulator, 700: display device, 701: substrate, 701B: substrate, 702: pixel, 703: pixel, 705: substrate, 712: sealing material, 716: FPC, 730: insulator, 732: sealing layer, 734: insulator, 738: light-shielding layer, 750: transistor, 760: connection electrode, 772: conductor, 778: structure, 780: anisotropic conductor, 786: light-emitting layer, 788: conductor, 7 90: Capacitor, 800: Transistor, 801a: Conductor, 801b: Conductor, 805: Conductor, 811: Conductor, 813: Conductor, 814: Insulator, 816: Insulator, 817: Conductor, 821: Insulator, 822: Insulator, 824: Insulator, 853: Conductor, 854: Insulator, 855: Conductor, 874: Insulator, 880: Insulator, 881: Insulator, 8200: Head-mounted display, 8201: Mounting part, 8202: Lens, 8203: Main body, 8204: Display part, 8205: Cable 8206: Battery, 8300: Head-mounted display, 8301: Housing, 8302: Display unit, 8304: Fixture, 8305: Lens, 8306: Battery, 9000: Housing, 9001: Display unit, 9003: Speaker, 9005: Operation keys, 9006: Connection terminal, 9007: Sensor, 9009: Battery, 9050: Operation button, 9051: Information, 9101: Portable information terminal, 9200: Portable information terminal, 9251: Time, 9252: Operation button, 9253: Content,
Claims
1. a first set of pixels; a second set of pixels; and a third set of pixels; and A first conductive film; A second conductive film; An eighth conductive film; and a ninth conductive film; the first set of pixels comprises a first set of light emitting devices, a first pad, a second pad, a conductive material, and a first set of pixel circuits; the first set of light emitting devices are electrically connected to the first pad; the first pad overlaps the second pad; the conductive material is sandwiched between the first pad and the second pad; the conductive material electrically connects the first pad and the second pad; the second pad is electrically connected to the first set of pixel circuits; the first set of pixel circuits includes a first group of pixel circuits; the first group of pixel circuits includes a first pixel circuit; the second set of pixels comprising a second set of light emitting devices and a second set of pixel circuits; the second set of light emitting devices are electrically connected to the second set of pixel circuits; the second set of pixel circuits includes a second group of pixel circuits; the second group of pixel circuits includes a second pixel circuit; the third set of pixels comprises a third set of light emitting devices and a third set of pixel circuits; the third set of light emitting devices are electrically connected to the third set of pixel circuits; the first conductive film is electrically connected to the first group of pixel circuits and the second group of pixel circuits; the second conductive film is electrically connected to the first pixel circuit and the second pixel circuit; the first pixel circuit includes a first switch, a second switch, a transistor, a capacitance, and a node; the first switch has a first terminal electrically connected to the eighth conductive film, a second terminal electrically connected to the node, and a function of controlling a conductive state or a non-conductive state based on a potential of the first conductive film; the transistor includes a gate electrode electrically connected to the node and a first electrode electrically connected to the ninth conductive film; the capacitance includes a conductive film electrically connected to the node and a conductive film electrically connected to the ninth conductive film; the second switch has a first terminal electrically connected to a second electrode of the transistor, a second terminal electrically connected to the second pad, and a function of controlling a conductive state or a non-conductive state based on a second selection signal.
2. a first set of pixels; a second set of pixels; and a third set of pixels; and A first conductive film; A third conductive film; An eighth conductive film; and a ninth conductive film; the first set of pixels comprises a first set of light emitting devices, a first pad, a second pad, a conductive material, and a first set of pixel circuits; the first set of light emitting devices are electrically connected to the first pad; the first pad overlaps the second pad; the conductive material is sandwiched between the first pad and the second pad; the conductive material electrically connects the first pad and the second pad; the second pad is electrically connected to the first set of pixel circuits; the first set of pixel circuits includes a first group of pixel circuits; the first group of pixel circuits includes a first pixel circuit; the second set of pixels comprising a second set of light emitting devices and a second set of pixel circuits; the second set of light emitting devices are electrically connected to the second set of pixel circuits; the second set of pixel circuits includes a second group of pixel circuits; the second group of pixel circuits includes a second pixel circuit; the third set of pixels comprises a third set of light emitting devices and a third set of pixel circuits; the third set of light emitting devices are electrically connected to the third set of pixel circuits; the third set of pixel circuits includes a third group of pixel circuits; the third group of pixel circuits includes a third pixel circuit; the first conductive film is electrically connected to the first group of pixel circuits and the second group of pixel circuits; the third conductive film is electrically connected to the first pixel circuit and the third pixel circuit; the first pixel circuit includes a first switch, a second switch, a transistor, a capacitance, and a node; the first switch has a first terminal electrically connected to the eighth conductive film, a second terminal electrically connected to the node, and a function of controlling a conductive state or a non-conductive state based on a potential of the first conductive film; the transistor includes a gate electrode electrically connected to the node and a first electrode electrically connected to the ninth conductive film; the capacitance includes a conductive film electrically connected to the node and a conductive film electrically connected to the ninth conductive film; the second switch has a first terminal electrically connected to a second electrode of the transistor, a second terminal electrically connected to the second pad, and a function of controlling a conductive state or a non-conductive state based on a second selection signal.
3. a first set of pixels; a second set of pixels; and a third set of pixels; and A first conductive film; A fourth conductive film; A fifth conductive film; An eighth conductive film; and a ninth conductive film; the first set of pixels comprises a first set of light emitting devices, a first pad, a second pad, a conductive material, and a first set of pixel circuits; the first set of light emitting devices are electrically connected to the first pad; the first pad overlaps the second pad; the conductive material is sandwiched between the first pad and the second pad; the conductive material electrically connects the first pad and the second pad; the second pad is electrically connected to the first set of pixel circuits; the first set of pixel circuits includes a first group of pixel circuits; the first group of pixel circuits includes a first pixel circuit; the second set of pixels comprising a second set of light emitting devices and a second set of pixel circuits; the second set of light emitting devices are electrically connected to the second set of pixel circuits; the second set of pixel circuits includes a second group of pixel circuits; the second group of pixel circuits includes a second pixel circuit; the third set of pixels comprises a third set of light emitting devices; the third set of light emitting devices are electrically connected to the third set of pixel circuits; the third set of pixel circuits includes a third group of pixel circuits; the third group of pixel circuits includes a third pixel circuit; the first conductive film is electrically connected to the first group of pixel circuits and the second group of pixel circuits; the fourth conductive film is electrically connected to the first pixel circuit and the second pixel circuit; the fifth conductive film is electrically connected to the first pixel circuit and the third pixel circuit; the first pixel circuit includes a first switch, a second switch, a transistor, a capacitance, and a node; the first switch has a first terminal electrically connected to the eighth conductive film, a second terminal electrically connected to the node, and a function of controlling a conductive state or a non-conductive state based on a potential of the first conductive film; the transistor includes a gate electrode electrically connected to the node and a first electrode electrically connected to the ninth conductive film; the capacitance includes a conductive film electrically connected to the node and a conductive film electrically connected to the ninth conductive film; the second switch has a first terminal electrically connected to a second electrode of the transistor, a second terminal electrically connected to the second pad, and a function of controlling a conductive state or a non-conductive state based on a second selection signal.
4. A sixth conductive film is provided, the first set of light emitting devices includes a first light emitting device; the second set of light emitting devices includes a second light emitting device; 4. The display device according to claim 1, wherein the sixth conductive film is electrically connected to the first light emitting device and the second light emitting device.
5. A seventh conductive film is provided, the first set of light emitting devices includes a first light emitting device; the third set of light emitting devices includes a third light emitting device; 5. The display device according to claim 1, wherein the seventh conductive film is electrically connected to the first light emitting device and the third light emitting device.
6. 6. The display device according to claim 4, wherein the first light-emitting device is a light-emitting diode.
7. A first drive circuit is provided. the first drive circuit supplies a first selection signal to the first conductive film; the first drive circuit provides a second select signal; The display device according to claim 4 , wherein the first drive circuit controls a potential of the sixth conductive film.
8. A first functional layer; A second functional layer, the first functional layer includes the first set of pixel circuits and the second pad; the second functional layer overlaps the first functional layer; The display device according to claim 1 , wherein the second functional layer includes the first set of light-emitting devices and the first pad.
9. A third functional layer is provided, the third functional layer has a region sandwiching the first functional layer between itself and the second functional layer, the third functional layer includes a second drive circuit; The display device according to claim 8 , wherein the second drive circuit has a function of supplying an image signal.
10. A calculation unit; The display device according to any one of claims 1 to 9, The calculation unit generates image information, The display device is an electronic device that displays the image information.
11. A display device according to claim 9 ; A calculation unit, the third functional layer includes the calculation unit, The calculation unit generates image information, The display device is an electronic device that displays the image information.