Display device

Abstract

To provide a display device which has high display quality, and to provide a display device which has low power consumption.SOLUTION: A display device is provided, having, in a pixel, a first transistor, a second transistor, a first conductive layer, and a light-emitting diode package. The light-emitting diode package includes a first light-emitting diode, a second light-emitting diode, a second conductive layer, a third conductive layer, and a fourth conductive layer. The first light-emitting diode includes a first electrode and a second electrode. The second light-emitting diode includes a third electrode and a fourth electrode. One of the source and the drain of the first transistor is electrically connected to the first electrode via the second conductive layer. One of the source and the drain of the second transistor is electrically connected to the third electrode via the third conductive layer. The first conductive layer is electrically connected to each of the second and fourth electrodes via the fourth conductive layer. The first conductive layer is supplied with a constant potential.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] One embodiment of the present invention relates to a display device, a display module, and an electronic device.

[0002] Note that one embodiment of the present invention is not limited to the above technical field. Examples of the technical field of one embodiment of the present invention include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, an electronic device, a lighting device, an input device (e.g., a touch sensor), an input / output device (e.g., a touch panel), a driving method thereof, or a manufacturing method thereof. [Background technology]

[0003] In recent years, display devices using micro light emitting diodes (micro LEDs) as display elements have been proposed (for example, Patent Document 1). Display devices using micro LEDs as display elements have advantages such as high brightness, high contrast, and long life, and are being actively researched and developed as next-generation display devices. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US Patent Application Publication No. 2014 / 0367705 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of one embodiment of the present invention is to provide a display device with high definition.An object of one embodiment of the present invention is to provide a display device with high display quality.An object of one embodiment of the present invention is to provide a display device with low power consumption.An object of one embodiment of the present invention is to provide a display device with high reliability.

[0006] Note that the description of these problems does not preclude the existence of other problems. One embodiment of the present invention does not necessarily have to solve all of these problems. Problems other than these can be extracted from the description of the specification, drawings, and claims. [Means for solving the problem]

[0007] A display device according to one embodiment of the present invention includes a pixel including a first transistor, a second transistor, a first conductive layer, and a light-emitting diode package. The light-emitting diode package includes a first light-emitting diode, a second light-emitting diode, a second conductive layer, a third conductive layer, and a fourth conductive layer. The first light-emitting diode includes a first electrode and a second electrode. The second light-emitting diode includes a third electrode and a fourth electrode. One of a source or a drain of the first transistor is electrically connected to the first electrode through the second conductive layer. One of a source or a drain of the second transistor is electrically connected to the third electrode through the third conductive layer. The first conductive layer is electrically connected to the second electrode through the fourth conductive layer. The first conductive layer is electrically connected to the fourth electrode through the fourth conductive layer. A constant potential is supplied to the first conductive layer.

[0008] Alternatively, in a display device according to one embodiment of the present invention, a pixel includes a first transistor, a second transistor, a third transistor, a first conductive layer, and a light-emitting diode package. The light-emitting diode package includes a first light-emitting diode, a second light-emitting diode, a third light-emitting diode, a second conductive layer, a third conductive layer, a fourth conductive layer, and a fifth conductive layer. The first light-emitting diode includes a first electrode and a second electrode. The second light-emitting diode includes a third electrode and a fourth electrode. The third light-emitting diode includes a fifth electrode and a sixth electrode. One of a source or a drain of the first transistor is electrically connected to the first electrode through the second conductive layer. One of a source or a drain of the second transistor is electrically connected to the third electrode through the third conductive layer. One of a source or a drain of the third transistor is electrically connected to the fifth electrode through the fifth conductive layer. The first conductive layer is electrically connected to the second electrode through the fourth conductive layer. The first conductive layer is electrically connected to the fourth electrode through the fourth conductive layer. The first conductive layer is electrically connected to the sixth electrode through the fourth conductive layer. A constant potential is supplied to the first conductive layer.

[0009] The first light emitting diode, the second light emitting diode, and the third light emitting diode are preferably mini light emitting diodes, respectively. Or, the first light emitting diode, the second light emitting diode, and the third light emitting diode are preferably micro light emitting diodes, respectively.

[0010] The first light emitting diode, the second light emitting diode, and the third light emitting diode preferably emit light of different colors, for example, the first light emitting diode preferably emits red light, the second light emitting diode preferably emits green light, and the third light emitting diode preferably emits blue light.

[0011] Each of the first transistor, the second transistor, and the third transistor preferably has a metal oxide in a channel formation region.

[0012] The fourth conductive layer and the second electrode are preferably electrically connected to each other via a first wire.

[0013] The fourth conductive layer and the fourth electrode are preferably electrically connected to each other via a second wire.

[0014] The second conductive layer and the first electrode are preferably in contact with each other.

[0015] The third conductive layer and the third electrode are preferably electrically connected to each other via a third wire.

[0016] One embodiment of the present invention is a module having a display device of the above-mentioned configuration, and having a connector such as a flexible printed circuit (hereinafter referred to as FPC) or a TCP (Tape Carrier Package) attached, or a module having an integrated circuit (IC) mounted by a COG (Chip On Glass) method or a COF (Chip On Film) method, or the like.

[0017] One embodiment of the present invention is an electronic device including any of the above modules and at least one of an antenna, a battery, a housing, a camera, a speaker, a microphone, and an operation button. Effect of the Invention

[0018] According to one embodiment of the present invention, a display device with high definition can be provided. According to one embodiment of the present invention, a display device with high display quality can be provided. According to one embodiment of the present invention, a display device with low power consumption can be provided. According to one embodiment of the present invention, a display device with high reliability can be provided.

[0019] Note that the description of these effects does not preclude the existence of other effects. One embodiment of the present invention does not necessarily have all of these effects. Effects other than these can be extracted from the description in the specification, drawings, and claims. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a top view illustrating an example of a display device. [Diagram 2] (A) is a cross-sectional view showing an example of a display device, (B) is a cross-sectional view showing an example of an LED package, and (C) is a cross-sectional view showing an example of an LED chip. [Diagram 3] (A) is a cross-sectional view showing an example of a display device, (B) and (D) are cross-sectional views showing an example of an LED package, and (C) is a cross-sectional view showing an example of an LED chip. [Figure 4] FIG. 1 is a cross-sectional view showing an example of a display device. [Diagram 5] FIG. 1 is a cross-sectional view showing an example of a display device. [Figure 6] FIG. 1 is a cross-sectional view showing an example of a display device. [Figure 7] FIG. 1 is a circuit diagram illustrating an example of a pixel of a display device. [Figure 8] 1A and 1B are diagrams showing examples of electronic devices. [Figure 9] 1A and 1B are diagrams showing examples of electronic devices. [Figure 10] 1A and 1B are diagrams showing examples of electronic devices. [Figure 11] (A)(B)(C)(D) are diagrams showing examples of electronic devices. [Figure 12] (A)(B)(C)(D)(E)(F) Diagrams showing examples of electronic devices. [Figure 13] 4 is a display photograph of the display device of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] 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 easily understood by those skilled in the art that the modes and details of the present invention can be modified in various ways 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.

[0022] In the configuration of the invention described below, the same parts or parts having similar functions are denoted by the same reference numerals in different drawings, and the repeated explanations are omitted. In addition, when referring to similar functions, the same hatch pattern may be used and no particular reference numeral may be used.

[0023] In addition, for ease of understanding, the position, size, range, etc. of each component shown in the drawings may not represent the actual position, size, range, etc. Therefore, the disclosed invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings.

[0024] In addition, the words "film" and "layer" can be interchanged depending on the case or situation. 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".

[0025] (Embodiment 1) In this embodiment, a display device according to one embodiment of the present invention will be described with reference to FIGS.

[0026] [Display device overview] In the display device of this embodiment, a pixel includes a first transistor, a second transistor, a first conductive layer, and a light-emitting diode package (also referred to as an LED package).

[0027] An LED package has a configuration in which one or more light emitting diodes (or light emitting diode chips (also referred to as LED chips)) are sealed in a lead frame, a board, a case, or the like.

[0028] The LED package includes a first light emitting diode, a second light emitting diode, a second conductive layer, a third conductive layer, and a fourth conductive layer.

[0029] The first light-emitting diode has a first electrode and a second electrode. The first electrode functions as a pixel electrode of the first light-emitting diode. One of a source and a drain of the first transistor is electrically connected to the first electrode through the second conductive layer.

[0030] The second light-emitting diode has a third electrode and a fourth electrode. The third electrode functions as a pixel electrode of the second light-emitting diode. One of a source and a drain of the second transistor is electrically connected to the third electrode through a third conductive layer.

[0031] The second electrode functions as a common electrode for the first light emitting diode, and the fourth electrode functions as a common electrode for the second light emitting diode. The first conductive layer is electrically connected to the second electrode through the fourth conductive layer. The first conductive layer is electrically connected to the fourth electrode through the fourth conductive layer. A constant potential is supplied to the first conductive layer.

[0032] The display device of this embodiment can be manufactured by mounting an LED package on a circuit board on which a plurality of transistors are formed. Therefore, compared with a method of mounting light-emitting diodes (or LED chips) one by one on a circuit board, the manufacturing time of the display device can be shortened and the manufacturing difficulty can be reduced. This can increase the manufacturing yield of the display device. Also, the display device can be made larger and with higher resolution.

[0033] The display device of this embodiment has a function of displaying an image using light-emitting diodes. Since light-emitting diodes are self-emitting elements, when light-emitting diodes are used as display elements, the display device does not require 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. In addition, a display device using light-emitting diodes as display elements has high contrast and a wide viewing angle, and therefore high display quality can be obtained. In addition, by using an inorganic material as a light-emitting material, the life of the display device can be extended and the reliability can be increased.

[0034] In this specification, the area of ​​the chip is 10,000 μm 2 Micro LED is a light-emitting diode with a chip area of ​​10,000 μm 2 1mm larger 2 A light-emitting diode with a chip area of ​​1 mm or less is called a mini LED. 2 Larger light emitting diodes are sometimes referred to as macro LEDs.

[0035] For example, if the outer dimensions of the chip are 100 μm 2 The following light-emitting diodes can be considered micro LEDs (micro LED chips): For example, a 1mm square LED package can use a micro LED chip or a mini LED chip.

[0036] In the display device of one embodiment of the present invention, any of a micro LED, a mini LED, and a macro LED may be used. In particular, the display device of one embodiment of the present invention preferably has a micro LED or a mini LED, and more preferably has a micro LED.

[0037] The area of ​​a light-emitting diode chip is 1 mm 2 Less than 10000μm is preferable. 2 Less than 3000μm is more preferable. 2 Less than 700μm is more preferable. 2 The following is even more preferred:

[0038] The area of ​​the light-emitting diode that emits light is 1 mm 2 Less than 10000μm is preferable. 2 Less than 3000μm is more preferable. 2 Less than 700μm is more preferable. 2 The following is even more preferred:

[0039] In this embodiment, in particular, an example in which a micro LED is used as a light emitting diode will be described. In this embodiment, a micro LED having a double heterojunction will be described. However, the light emitting diode is not particularly limited, and for example, a micro LED having a quantum well junction, an LED using a nanocolumn, etc. may be used.

[0040] The transistors in the display device preferably have a metal oxide in the channel formation region. A transistor using a metal oxide can reduce power consumption. Therefore, by combining a transistor with a micro LED, a display device with extremely low power consumption can be realized.

[0041] [Display device configuration example 1] 1A shows a top view of a display device 100. The display device 100 includes a plurality of pixels 130 in a display portion 110. The plurality of pixels 130 are arranged in a matrix in the display portion 110. Signals and power are supplied to the display portion 110 from FPC1 and FPC2 via wirings 108.

[0042] 1B shows a top view of the display device 100A. The display device 100A includes a circuit 109 between a display portion 110 and a wiring 108. Signals and power are supplied to the display portion 110 and the circuit 109 from an FPC1 or an FPC2 through the wiring 108.

[0043] The display device of one embodiment of the present invention can have one or both of a scan line driver circuit (gate driver) and a signal line driver circuit (source driver) built in. Alternatively, the display device of one embodiment of the present invention can have a configuration in which one or both of a gate driver and a source driver are not built in and a driver is provided externally. For example, an IC functioning as a gate driver or a source driver can be electrically connected to the display device. The IC can be mounted on the display device by a COG method or a COF method. Alternatively, an FPC, a TAB (Tape Automated Bonding) tape, a TCP, or the like on which an IC is mounted can be connected to the display device.

[0044] As the circuit 109, for example, one or both of a gate driver and a source driver can be used.

[0045] 1C shows a top view of a pixel 130 included in the display device 100. One LED package 150 is provided in one pixel 130. That is, a plurality of LED packages 150 are provided in a matrix in the display unit 110 shown in FIG.

[0046] The pixel 130 includes a conductive layer 131R, a conductive layer 131G, a conductive layer 131B, a conductive layer 132, and an LED package 150.

[0047] FIG. 1D shows a top view of the LED package 150 included in the pixel 130. As shown in FIG.

[0048] The LED package 150 has at least one LED chip. In this embodiment, an example is shown in which the LED package 150 has a red LED chip 151R, a green LED chip 151G, and a blue LED chip 151B. That is, in this embodiment, a configuration is applied in which one color is expressed by three sub-pixels of R (red), G (green), and B (blue).

[0049] In addition, the pixel 130 may be configured to express one color using four sub-pixels of R, G, B, and W (white), or to express one color using four sub-pixels of R, G, B, and Y (yellow). There is no limitation on the color elements, and colors other than RGBWY (for example, cyan or magenta) may be used.

[0050] The LED package 150 further includes a heat sink 154, an electrode 152R, an electrode 152G, an electrode 152B, and an electrode 153.

[0051] The red LED chip 151R is located on the electrode 152R. The green LED chip 151G and the blue LED chip 151B are located on the heat sink 154.

[0052] The red LED chip 151R, the green LED chip 151G, and the blue LED chip 151B are electrically connected to the electrodes 153 via wires 143, respectively.

[0053] It is preferable that the red LED chip 151R, the green LED chip 151G, and the blue LED chip 151B have light emitting diodes that emit light of different colors. This eliminates the need for a step of forming a color conversion layer. This makes it possible to reduce the manufacturing cost of the LED chips.

[0054] The red LED chip 151R, the green LED chip 151G, and the blue LED chip 151B may each have a light emitting diode that emits light of the same color. In this case, the light emitted from the light emitting diode may be extracted to the outside of the display device via one or both of the color conversion layer and the coloring layer. One or both of the color conversion layer and the coloring layer may be provided inside or above the LED package 150.

[0055] The display device of this embodiment mode may include a light-emitting diode that emits infrared light. The light-emitting diode that emits infrared light can be used as a light source for an infrared light sensor, for example.

[0056] Fig. 2(A) shows a cross-sectional view taken along dashed line AB in Fig. 1(C). That is, Fig. 2(A) is a cross-sectional view including a blue LED chip 151B and conductive layers 131B and 132 electrically connected to the blue LED chip 151B. Note that, for clarity, some of the components, such as wiring, are omitted in Fig. 2(A).

[0057] The cross-sectional structure including the green LED chip 151G and the conductive layer 131G and conductive layer 132 electrically connected to the green LED chip 151G is also similar to that in FIG. 2(A), and therefore the following description can be referred to.

[0058] As shown in FIG. 2A, in the display device 100, the transistor 120 is electrically connected to the LED package 150 via a conductive layer 131B.

[0059] The transistor 120 includes a conductive layer 121 functioning as a back gate, an insulating layer 122 functioning as a gate insulating layer, a metal oxide layer 123 (a channel formation region 123i and a pair of low-resistance regions 123n) functioning as a semiconductor layer, a pair of conductive layers 126a and 126b electrically connected to the low-resistance region 123n, an insulating layer 124 functioning as a gate insulating layer, and a conductive layer 125 functioning as a gate. The conductive layer 121 and the metal oxide layer 123 overlap with the insulating layer 122 interposed therebetween. The conductive layer 125 and the metal oxide layer 123 overlap with the insulating layer 124 interposed therebetween.

[0060] An insulating layer 127 is provided over the transistor 120, and a conductive layer 131B and a conductive layer 132 are provided over the insulating layer 127. The conductive layer 131B is electrically connected to the conductive layer 126b through an opening provided in the insulating layer 127.

[0061] At least one of the insulating layers 124 and 127 is preferably made of a material through which impurities such as water or hydrogen do not easily diffuse. This makes it possible to effectively prevent impurities from diffusing into the transistor from the outside, thereby improving the reliability of the display device. The insulating layer 127 functions as a planarization layer.

[0062] In FIG. 2A, the transistor 120 is provided over the substrate 102 with an insulating layer 104 interposed therebetween. The insulating layer 104 functions as a base film. The insulating layer 104 functions as a barrier layer that prevents impurities such as water and hydrogen from diffusing from the substrate 102 to the transistor 120 and prevents oxygen from being released from the metal oxide layer 123 toward the insulating layer 104. As the insulating layer 104, for example, a film through which hydrogen and oxygen are less likely to diffuse than a silicon oxide film, such as an aluminum oxide film, a hafnium oxide film, or a silicon nitride film, can be used. Note that the transistor 120 may be formed directly over the substrate 102 without providing the insulating layer 104.

[0063] An end of the conductive layer 131B and an end of the conductive layer 132 are covered with a protective layer 128. The protective layer 128 has an opening that reaches the upper surface of the conductive layer 131B and an opening that reaches the upper surface of the conductive layer 132. In the openings, the conductive layer 131B and the conductive layer 132 are electrically connected to the LED package 150 via the conductor 133, respectively.

[0064] Resins such as acrylic, polyimide, epoxy, and silicone are suitable materials for the protective layer 128. Providing the protective layer 128 can prevent the conductor 133 on the conductive layer 131B and the conductor 133 on the conductive layer 132 from coming into contact with each other and causing a short circuit. Note that the protective layer 128 does not necessarily have to be provided.

[0065] For example, conductive paste such as silver, carbon, or copper, or bumps such as gold or solder can be suitably used for the conductor 133. Also, for the conductive layers 131R, 131G, 131B, and 132 and the electrodes 152R, 152G, 152B, and 153 connected to the conductor 133, it is preferable to use a conductive material having low contact resistance with the conductor 133. For example, when silver paste is used for the conductor 133, it is preferable that the conductive material connected thereto is aluminum, titanium, copper, or an alloy of silver (Ag), palladium (Pd), and copper (Cu) (Ag-Pd-Cu(APC)), etc., because these have low contact resistance.

[0066] The conductor 133 may be provided on the substrate 102 or on the LED package 150 side. For example, the conductor 133 is provided on each of the conductive layers 131R, 131G, 131B, and 132, and then the conductor 133 and the LED package 150 are connected to each other, whereby the LED package 150 can be mounted on the substrate 102.

[0067] A plurality of light emitting diodes may be electrically connected to one transistor.

[0068] The side of the LED package 150 may be covered with resin 129. It is preferable to use a black resin as the resin 129, since this increases the contrast of the display. In addition, a surface protection layer, a shock absorbing layer, and the like may be provided on the upper surface of the LED package 150. Since the LED package 150 is configured to extract light upward, it is preferable that the layer provided on the upper surface of the LED package 150 is transparent to visible light.

[0069] The substrate 102 can be an insulating substrate such as a glass substrate, a quartz substrate, a sapphire substrate, or a ceramic substrate, or a semiconductor substrate such as a single crystal semiconductor substrate made of silicon, silicon carbide, or the like, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, or an SOI substrate.

[0070] The substrate 102 preferably blocks visible light (is non-transparent to visible light). When the substrate 102 blocks visible light, it is possible to prevent light from entering the transistor 120 formed over the substrate 102 from the outside. However, one embodiment of the present invention is not limited thereto, and the substrate 102 may be transparent to visible light.

[0071] Furthermore, the substrate 102 may have one or both of a reflective layer that reflects light from the light-emitting diode and a light-shielding layer that blocks the light.

[0072] The multiple light emitting diodes (LED chips) of the LED package 150 may be driven by transistors of the same configuration, or may be driven by transistors of different configurations. For example, the transistor driving the red LED chip 151R, the transistor driving the green LED chip 151G, and the transistor driving the blue LED chip 151B may differ from each other in at least one of the transistor size, channel length, channel width, and structure. Specifically, one or both of the channel length and channel width of the transistor may be changed for each color according to the amount of current required to emit light at a desired brightness.

[0073] Materials that can be used for various conductive layers constituting the display device of this embodiment include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, and tungsten, or alloys containing these as main components. Films containing these materials can be used as a single layer or a laminated structure. For example, there are a single layer structure of an aluminum film containing silicon, a two-layer structure in which an aluminum film is laminated on a titanium film, a two-layer structure in which an aluminum film is laminated on a tungsten film, a two-layer structure in which a copper film is laminated on a copper-magnesium-aluminum alloy film, a two-layer structure in which a copper film is laminated on a titanium film, a two-layer structure in which a copper film is laminated on a tungsten film, a three-layer structure in which a titanium film or titanium nitride film is laminated on the titanium film or titanium nitride film, and a three-layer structure in which an aluminum film or copper film is laminated on the titanium film or titanium nitride film, and a three-layer structure in which an aluminum film or copper film is laminated on the molybdenum film or molybdenum nitride film is laminated on the molybdenum film or molybdenum nitride film is formed on the molybdenum film or molybdenum nitride film. Alternatively, oxides such as indium oxide, tin oxide, zinc oxide, etc. may be used. Furthermore, copper containing manganese is preferably used because it enhances the controllability of the shape by etching.

[0074] Materials that can be used for the various insulating layers that constitute the display device of this embodiment include resins such as acrylic, polyimide, epoxy, and silicone, and inorganic insulating materials such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, and aluminum oxide.

[0075] The LED package 150 will be described in more detail with reference to Fig. 2(B), and the blue LED chip 151B will be described in more detail with reference to Fig. 2(C).

[0076] The LED package 150 shown in FIG. 2B includes a substrate 141, a blue LED chip 151B, an electrode 152B, an electrode 153, a heat sink 154, an adhesive layer 146, a case 142, a wire 143, a wire 144, and a sealing layer 145.

[0077] The blue LED chip 151B is attached to the substrate 141 by the adhesive layer 146. The blue LED chip 151B is provided so as to overlap the heat sink 154 via the adhesive layer 146. There is no particular limitation on the material of the adhesive layer 146. However, as described later, since the red LED chip 151R is attached to the electrode 152R so as to be electrically connected to the electrode 152R, it is preferable that the adhesive layer 146 has conductivity, since the material of the adhesive layer 146 can be uniform for the LED chips of each color. In addition, in the blue LED chip and the green LED chip, it is preferable to use an adhesive having conductivity as the adhesive layer 146, since the heat dissipation is enhanced. The heat sink 154 can be formed of the same material and in the same process as the electrodes 152B and 153.

[0078] The substrate 141 may be a glass epoxy resin substrate, a polyimide substrate, a ceramic substrate, an alumina substrate, an aluminum nitride substrate, or the like.

[0079] 2C has a configuration in which a light emitting diode (LED) is provided on a substrate 101. The light emitting diode has a semiconductor layer 111, an electrode 112, a light emitting layer 113, a semiconductor layer 114, an electrode 115, and an electrode .

[0080] The electrode 112 is electrically connected to the semiconductor layer 111. The electrode 116 is electrically connected to the semiconductor layer 114 via the electrode 115. Only one of the electrodes 115 and 116 may be provided. The light-emitting layer 113 is sandwiched between the semiconductor layer 111 and the semiconductor layer 114. In the light-emitting layer 113, electrons and holes combine to emit light. One of the semiconductor layer 111 and the semiconductor layer 114 is an n-type semiconductor layer, and the other is a p-type semiconductor layer.

[0081] In the blue LED chip 151B, a laminate structure including the semiconductor layer 111, the light emitting layer 113, and the semiconductor layer 114 is formed to emit blue light.

[0082] In the light-emitting diodes of each color, a stacked structure having a pair of semiconductor layers and a light-emitting layer between the pair of semiconductor layers is formed to emit light of red, yellow, green, blue, etc. For the stacked structure, for example, a gallium phosphide compound, a gallium arsenide compound, a gallium aluminum arsenide compound, an aluminum gallium indium phosphide compound, a gallium nitride, an indium gallium nitride compound, a selenium zinc compound, etc. can be used.

[0083] As the substrate 101, for example, a single crystal substrate such as a sapphire (Al2O3) substrate, a silicon carbide (SiC) substrate, a silicon (Si) substrate, or a gallium nitride (GaN) substrate can be used.

[0084] The electrode 112 is electrically connected to the electrode 152B via the wire 143. The electrode 112 functions as a pixel electrode of the light-emitting diode. The electrode 116 is electrically connected to the electrode 153 via the wire 144. The electrode 116 functions as a common electrode of the light-emitting diode.

[0085] The electrodes 152B and 153 can each be made of an element selected from nickel, copper, silver, platinum, or gold, or an alloy material containing 50% or more of the element.

[0086] The connection between electrode 152B and electrode 112, and the connection between electrode 153 and electrode 116 can be made by wire bonding using thermocompression bonding or ultrasonic bonding.

[0087] The wires 143 and 144 may each be a thin metal wire made of gold, an alloy containing gold, copper, an alloy containing copper, or the like.

[0088] The case 142 may be made of a resin. The case 142 may cover at least the side surface of the blue LED chip 151B, and may not overlap the upper surface of the blue LED chip 151B. For example, the sealing layer 145 may be exposed on the upper surface side of the blue LED chip 151B. It is preferable to provide a reflector made of ceramic or the like on the inner side surface of the case 142, specifically, around the blue LED chip 151B. By reflecting a part of the light emitted by the blue LED chip 151B by the reflector, more light can be extracted from the LED package 150.

[0089] The inside of the case 142 is filled with a sealing layer 145. A resin having transparency to visible light is suitable for the sealing layer 145. For example, an ultraviolet-curable resin such as an epoxy resin or a silicone resin, or a visible-light-curable resin can be used for the sealing layer 145.

[0090] Fig. 3(A) shows a cross-sectional view taken along dashed line CD in Fig. 1(C). That is, Fig. 3(A) is a cross-sectional view including a red LED chip 151R and conductive layers 131R and 132 electrically connected to the red LED chip 151R. Note that, for clarity, some of the components, such as wiring, are omitted in Fig. 3(A).

[0091] As shown in FIG. 3A, in the display device 100, the transistor 120A is electrically connected to the LED package 150 via a conductive layer 131R.

[0092] The transistor 120A has a structure similar to that of the transistor 120 shown in FIG. 2A, and therefore detailed description thereof will be omitted.

[0093] An insulating layer 127 is provided over the transistor 120A, and a conductive layer 131R and a conductive layer 132 are provided over the insulating layer 127. The conductive layer 131R is electrically connected to the conductive layer 126b through an opening provided in the insulating layer 127.

[0094] The conductive layer 131R and the conductive layer 132 are electrically connected to the LED package 150 via the conductor 133, respectively.

[0095] The LED package 150 will be described in more detail with reference to Figure 3(B), and the red LED chip 151R will be described in more detail with reference to Figure 3(C).

[0096] The LED package 150 shown in FIG. 3B includes the substrate 141, a red LED chip 151R, an electrode 152R, an electrode 153, an adhesive layer 146, a case 142, a wire 144, and a sealing layer 145.

[0097] The red LED chip 151R is electrically connected to an electrode 152R via a conductive adhesive layer 146.

[0098] 3(C) includes an electrode 103, a semiconductor layer 117, a light-emitting layer 118, a semiconductor layer 119, and an electrode 106. The red LED chip 151R can also be called a light-emitting diode (LED). The red LED chip may have a configuration in which a light-emitting diode is provided on a conductive substrate.

[0099] The electrode 103 is electrically connected to the semiconductor layer 117. The electrode 106 is electrically connected to the semiconductor layer 119. The light emitting layer 118 is sandwiched between the semiconductor layer 117 and the semiconductor layer 119. In the light emitting layer 118, electrons and holes combine to emit light. One of the semiconductor layer 117 and the semiconductor layer 119 is an n-type semiconductor layer, and the other is a p-type semiconductor layer.

[0100] The electrode 103 is electrically connected to the electrode 152R via the adhesive layer 146. The electrode 103 functions as a pixel electrode of the light-emitting diode. The electrode 106 is electrically connected to the electrode 153 via the wire 144. The electrode 106 functions as a common electrode of the light-emitting diode.

[0101] 3(D), a color conversion layer 147 may be provided inside the case 142. This allows light from the light emitting diode to be emitted to the outside of the LED package 155 through the color conversion layer 147.

[0102] 3D shows a configuration in which the color conversion layer 147 is provided above the sealing layer 145, but the arrangement of the color conversion layer 147 is not limited thereto. For example, the color conversion layer 147 may be dispersed inside the sealing layer 145.

[0103] It is preferable to use a phosphor or a quantum dot (QD) as the color conversion layer 147. In particular, quantum dots have a narrow peak width of the emission spectrum, and can emit light with good color purity. This can improve the display quality of the display device.

[0104] For example, when all of the multiple LED chips included in the LED package 155 have light emitting diodes that emit blue light, it is preferable that a color conversion layer 147 is provided inside or above the LED package 155. Specifically, it is preferable that a color conversion layer 147 that converts blue light to red is provided at a position overlapping the red LED chip 151R, and a color conversion layer 147 that converts blue light to green is provided at a position overlapping the green LED chip 151G.

[0105] As a result, in the red subpixel, light emitted by the light emitting diode is converted from blue to red by the color conversion layer 147 and emitted to the outside of the display device. In the green subpixel, light emitted by the light emitting diode is converted from blue to green by the color conversion layer 147 and emitted to the outside of the display device. In the blue subpixel, blue light emitted by the light emitting diode is directly emitted to the outside of the display device.

[0106] The color conversion layer 147 can be formed by using a droplet discharge method (for example, an inkjet method), a coating method, an imprint method, various printing methods (screen printing, offset printing), etc. Also, a color conversion film such as a quantum dot film may be used.

[0107] As the phosphor, an organic resin layer having a phosphor printed or painted on its surface, an organic resin layer having a phosphor mixed therein, or the like can be used.

[0108] The material constituting the quantum dots is not particularly limited, and examples thereof include Group 14 elements, Group 15 elements, Group 16 elements, compounds consisting of multiple Group 14 elements, compounds of an element belonging to Groups 4 to 14 and a Group 16 element, compounds of a Group 2 element and a Group 16 element, compounds of a Group 13 element and a Group 15 element, compounds of a Group 13 element and a Group 17 element, compounds of a Group 14 element and a Group 15 element, compounds of a Group 11 element and a Group 17 element, iron oxides, titanium oxides, chalcogenide spinels, and semiconductor clusters.

[0109] Specifically, cadmium selenide, cadmium sulfide, cadmium telluride, zinc selenide, zinc oxide, zinc sulfide, zinc telluride, mercury sulfide, mercury selenide, mercury telluride, indium arsenide, indium phosphide, gallium arsenide, gallium phosphide, indium nitride, gallium nitride, indium antimonide, gallium antimonide, aluminum phosphide, aluminum arsenide, aluminum antimonide, lead selenide, lead telluride, lead sulfide, indium selenide, terbium Indium sulfide, Indium sulfide, Gallium selenide, Arsenic sulfide, Arsenic selenide, Arsenic telluride, Antimony sulfide, Antimony selenide, Antimony telluride, Bismuth sulfide, Bismuth selenide, Bismuth telluride, Silicon, Silicon carbide, Germanium, Tin, Selenium, Tellurium, Boron, Carbon, Phosphorus, Boron nitride, Boron phosphide, Boron arsenide, Aluminum nitride, Aluminum sulfide, Barium sulfide, Barium selenide, Barium telluride, Calcium sulfide, Selenide Calcium, calcium telluride, beryllium sulfide, beryllium selenide, beryllium telluride, magnesium sulfide, magnesium selenide, germanium sulfide, germanium selenide, germanium telluride, tin sulfide, tin selenide, tin telluride, lead oxide, copper fluoride, copper chloride, copper bromide, copper iodide, copper oxide, copper selenide, nickel oxide, cobalt oxide, cobalt sulfide, iron oxide, iron sulfide, manganese oxide, molybdenum sulfide, vanadium oxide, tungsten oxide, tungsten oxide Examples of the quantum dots include talc, titanium oxide, zirconium oxide, silicon nitride, germanium nitride, aluminum oxide, barium titanate, a compound of selenium, zinc, and cadmium, a compound of indium, arsenic, and phosphorus, a compound of cadmium, selenium, and sulfur, a compound of cadmium, selenium, and tellurium, a compound of indium, gallium, and arsenic, a compound of indium, gallium, and selenium, a compound of indium, selenium, and sulfur, a compound of copper, indium, and sulfur, and combinations thereof. In addition, so-called alloy-type quantum dots whose composition is expressed in any ratio may be used.

[0110] Examples of the structure of quantum dots include core type, core-shell type, and core-multishell type. In addition, quantum dots have a high proportion of surface atoms, so they are highly reactive and prone to aggregation. Therefore, it is preferable that a protective agent is attached to the surface of the quantum dots or a protective group is provided. By attaching the protective agent or providing the protective group, aggregation can be prevented and solubility in a solvent can be increased. It is also possible to reduce reactivity and improve electrical stability.

[0111] The smaller the size of the quantum dot, the larger the band gap becomes, so the size is adjusted appropriately to obtain light of the desired wavelength. As the size of the crystal becomes smaller, the emission of the quantum dot shifts to the blue side, that is, to the high energy side, so that the emission wavelength can be adjusted over the wavelength range of the spectrum of the ultraviolet region, the visible region, and the infrared region by changing the size of the quantum dot. The size (diameter) of the quantum dot is, for example, 0.5 nm or more and 20 nm or less, preferably 1 nm or more and 10 nm or less. The narrower the size distribution of the quantum dot, the narrower the emission spectrum becomes, and light emission with good color purity can be obtained. In addition, the shape of the quantum dot is not particularly limited, and may be spherical, rod-shaped, disk-shaped, or other shapes. A quantum rod, which is a rod-shaped quantum dot, has the function of exhibiting light with directionality.

[0112] Alternatively, a laminated structure of color conversion layer 147 and a colored layer may be provided inside or above LED package 155. This allows the light converted by color conversion layer 147 to pass through the colored layer, thereby increasing the purity of the light. Also, a blue colored layer may be provided at a position overlapping with blue LED chip 151B. By providing a blue colored layer, the purity of blue light can be increased. If a blue colored layer is not provided, the manufacturing process can be simplified.

[0113] The colored layer is a colored layer that transmits light in a specific wavelength range. For example, a color filter that transmits light in a red, green, blue, or yellow wavelength range can be used. Examples of materials that can be used for the colored layer include metal materials, resin materials, and resin materials containing pigments or dyes.

[0114] [Display device configuration example 2] 4 to 6 show examples of cross-sectional configurations of a display device that are different from configuration example 1 of the display device.

[0115] The display device shown in FIGS. 4 to 6 differs from that shown in FIG. 2(A) mainly in the structure of the transistor electrically connected to the LED package 150.

[0116] In the display device shown in FIG. 4, the transistor 120B is electrically connected to the LED package 150 via the conductive layer 131B.

[0117] The transistor 120B includes a conductive layer 121 functioning as a gate, an insulating layer 122 functioning as a gate insulating layer, a metal oxide layer 123 functioning as a semiconductor layer, a pair of conductive layers 126a and 126b functioning as a source and a drain, insulating layers 124a and 124b functioning as gate insulating layers, and a conductive layer 125 functioning as a back gate. The conductive layer 121 and the metal oxide layer 123 overlap with the insulating layer 122 interposed therebetween. The conductive layer 125 and the metal oxide layer 123 overlap with the insulating layer 124a and the insulating layer 124b interposed therebetween.

[0118] An insulating layer 127 is provided over the transistor 120B, and a conductive layer 131B and a conductive layer 132 are provided over the insulating layer 127. The conductive layer 131B is electrically connected to the conductive layer 126b through an opening provided in the insulating layer 127.

[0119] In the display device shown in FIG. 5, the transistor 120C is electrically connected to the LED package 150 via the conductive layer 131B and the like.

[0120] An insulating layer 175, a transistor 120C, a conductive layer 184a, a conductive layer 184b, a conductive layer 187, a conductive layer 189, an insulating layer 186, an insulating layer 188, a conductive layer 131B, a conductive layer 132, and the like are provided on the substrate 174. Further, insulating layers, such as an insulating layer 162, an insulating layer 181, an insulating layer 182, an insulating layer 183, and an insulating layer 185, are provided on the substrate 174. One or more of these insulating layers may be considered as components of a transistor, but in the present embodiment, they will not be included in the components of a transistor.

[0121] The substrate 151 may be an insulating substrate such as a glass substrate, a quartz substrate, a sapphire substrate, or a ceramic substrate, or a semiconductor substrate such as a single crystal semiconductor substrate made of silicon, silicon carbide, or the like, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, or an SOI substrate.

[0122] The substrate 151 preferably blocks visible light (is opaque to visible light). When the substrate 151 blocks visible light, it is possible to prevent light from entering the transistor 120C formed over the substrate 151 from the outside. However, one embodiment of the present invention is not limited thereto, and the substrate 151 may be transmissive to visible light.

[0123] An insulating layer 175 is provided on the substrate 174. The insulating layer 175 functions as a barrier layer that prevents impurities such as water and hydrogen from diffusing from the substrate 174 to the transistor 120C and prevents oxygen from being released from the metal oxide layer 165 to the insulating layer 175 side. As the insulating layer 175, for example, a film in which hydrogen and oxygen are less likely to diffuse than a silicon oxide film, such as an aluminum oxide film, a hafnium oxide film, or a silicon nitride film, can be used.

[0124] The transistor 120C includes a conductive layer 161, an insulating layer 163, an insulating layer 164, a metal oxide layer 165, a pair of conductive layers 166, an insulating layer 167, a conductive layer 168, and the like.

[0125] The metal oxide layer 165 has a channel formation region. The metal oxide layer 165 has a first region overlapping with one of the pair of conductive layers 166, a second region overlapping with the other of the pair of conductive layers 166, and a third region between the first region and the second region.

[0126] The conductive layer 161 and the insulating layer 162 are provided over the insulating layer 175, and the insulating layer 163 and the insulating layer 164 are provided to cover the conductive layer 161 and the insulating layer 162. The metal oxide layer 165 is provided over the insulating layer 164. The conductive layer 161 functions as a gate electrode, and the insulating layer 163 and the insulating layer 164 function as gate insulating layers. The conductive layer 161 overlaps with the metal oxide layer 165 with the insulating layer 163 and the insulating layer 164 interposed therebetween. The insulating layer 163 preferably functions as a barrier layer, similar to the insulating layer 175. The insulating layer 164 in contact with the metal oxide layer 165 is preferably an oxide insulating film such as a silicon oxide film.

[0127] Here, the height of the upper surface of the conductive layer 161 is approximately the same as the height of the upper surface of the insulating layer 162. For example, by providing an opening in the insulating layer 162, forming the conductive layer 161 so as to fill the opening, and then performing a planarization process using a CMP method or the like, the height of the upper surface of the conductive layer 161 can be made the same as the height of the upper surface of the insulating layer 162. This allows the size of the transistor 120C to be reduced.

[0128] The pair of conductive layers 166 are provided on the metal oxide layer 165 with a space therebetween. The pair of conductive layers 166 function as a source and a drain. An insulating layer 181 is provided to cover the metal oxide layer 165 and the pair of conductive layers 166, and an insulating layer 182 is provided on the insulating layer 181. An opening reaching the metal oxide layer 165 is provided in the insulating layer 181 and the insulating layer 182, and the insulating layer 167 and the conductive layer 168 are embedded in the opening. The opening overlaps with the third region. The insulating layer 167 overlaps with a side surface of the insulating layer 181 and a side surface of the insulating layer 182. The conductive layer 168 overlaps with a side surface of the insulating layer 181 and a side surface of the insulating layer 182 with the insulating layer 167 interposed therebetween. The conductive layer 168 functions as a gate electrode, and the insulating layer 167 functions as a gate insulating layer. The conductive layer 168 overlaps with the metal oxide layer 165 with the insulating layer 167 interposed therebetween.

[0129] Here, the height of the top surface of the conductive layer 168 is approximately the same as the height of the top surface of the insulating layer 182. For example, by providing an opening in the insulating layer 182, forming the insulating layer 167 and the conductive layer 168 so as to fill the opening, and then performing a planarization treatment, the height of the top surface of the conductive layer 168 can be made the same as the height of the top surface of the insulating layer 182. This allows the size of the transistor 120C to be reduced.

[0130] An insulating layer 183 and an insulating layer 185 are provided to cover top surfaces of the insulating layer 182, the insulating layer 167, and the conductive layer 168. The insulating layer 181 and the insulating layer 183 preferably function as a barrier layer, similar to the insulating layer 175. Covering the pair of conductive layers 166 with the insulating layer 181 can prevent the pair of conductive layers 166 from being oxidized by oxygen contained in the insulating layer 182.

[0131] A plug electrically connected to one of the pair of conductive layers 166 and the conductive layer 187 is embedded in an opening provided in the insulating layers 181, 182, 183, and 185. The plug preferably has a conductive layer 184a in contact with the side surface of the opening and an upper surface of one of the pair of conductive layers 166, and a conductive layer 184b embedded inwardly of the conductive layer 184a. In this case, the conductive layer 184a is preferably made of a conductive material through which hydrogen and oxygen are unlikely to diffuse.

[0132] A conductive layer 187 is provided on insulating layer 185, and an insulating layer 186 is provided on conductive layer 187. An opening reaching conductive layer 187 is provided in insulating layer 186, and conductive layer 189 is embedded in the opening. Conductive layer 189 functions as a plug that electrically connects conductive layer 187 and conductive layer 131B.

[0133] One of the pair of conductive layers 166 is electrically connected to the conductive layer 131B via the conductive layer 184a, the conductive layer 184b, the conductive layer 187, and the conductive layer 189.

[0134] 5, the height of the top surface of the conductive layer 161 is approximately the same as the height of the top surface of the insulating layer 162. In addition, in the transistor 120C shown in FIG. 5, the height of the top surface of the conductive layer 168 is approximately the same as the height of the top surface of the insulating layer 182.

[0135] In this way, the display device of this embodiment preferably has a transistor in which the height of the upper surface of the gate electrode is approximately equal to the height of the upper surface of the insulating layer. For example, by performing a planarization process using a CMP (Chemical Mechanical Polishing) method or the like, the upper surfaces of the gate electrode and the insulating layer can be planarized, and the heights of the upper surfaces of the gate electrode and the insulating layer can be made equal to each other.

[0136] The size of a transistor having such a structure can be easily reduced, and by reducing the size of the transistor, the size of a pixel can be reduced, thereby improving the resolution of a display device.

[0137] In the display device shown in FIG. 6, similarly to the display device shown in FIG. 5, the transistor 120C is electrically connected to the LED package 150 via the conductive layer 131B and the like.

[0138] The display device illustrated in FIG. 6 includes a transistor 190 having a channel formation region over a substrate 191 and a transistor 120C having a channel formation region in a metal oxide, which are stacked together.

[0139] The substrate 191 is preferably a single crystal silicon substrate. The transistor 190 has a conductive layer 195, an insulating layer 194, an insulating layer 196, and a pair of low-resistance regions 193. The conductive layer 195 functions as a gate. The insulating layer 194 is located between the conductive layer 195 and the substrate 191 and functions as a gate insulating layer. The insulating layer 196 is provided to cover the side surface of the conductive layer 195 and functions as a sidewall. The pair of low-resistance regions 193 are regions in the substrate 191 doped with impurities, one of which functions as the source of the transistor 190 and the other of which functions as the drain of the transistor 190.

[0140] In addition, an element isolation layer 192 is provided between two adjacent transistors so as to be embedded in the substrate 191.

[0141] An insulating layer 199 is provided to cover the transistor 190, and a conductive layer 198 is provided on the insulating layer 199. The conductive layer 198 is electrically connected to one of the pair of low resistance regions 193 through an opening in the insulating layer 199. An insulating layer 171 is provided to cover the conductive layer 198, and a conductive layer 172 is provided on the insulating layer 171. The conductive layer 198 and the conductive layer 172 each function as a wiring. An insulating layer 173 and an insulating layer 175 are provided to cover the conductive layer 172, and a transistor 120C is provided on the insulating layer 175. The stacked structure from the insulating layer 175 to the LED package 150 is the same as that of the display device shown in FIG. 5, and therefore a detailed description thereof will be omitted.

[0142] The transistor 120C can be used as a transistor that constitutes a pixel circuit. The transistor 190 can be used as a transistor that constitutes a pixel circuit or a driver circuit (one or both of a gate driver and a source driver) for driving the pixel circuit. The transistors 120C and 190 can be used as transistors that constitute various circuits such as an arithmetic circuit or a memory circuit.

[0143] With this configuration, not only the pixel circuits but also the driving circuits can be formed directly under the light-emitting diodes, so the display device can be made smaller than when the driving circuits are provided outside the display section. Also, a display device with a narrow frame (narrow non-display area) can be realized.

[0144] The display device of one embodiment of the present invention may be a display device equipped with a touch sensor (also referred to as an input / output device or a touch panel). The structure of each of the above-described display devices can be applied to a touch panel.

[0145] There is no limitation on a sensing element (also referred to as a sensor element) included in a touch panel of one embodiment of the present invention. Various sensors capable of detecting the proximity or contact of a sensing object such as a finger or a stylus can be used as the sensing element.

[0146] As the sensor type, various types can be used, such as a capacitance type, a resistive film type, a surface acoustic wave type, an infrared type, an optical type, and a pressure sensitive type.

[0147] The capacitance type includes a surface capacitance type, a projected capacitance type, etc. The projected capacitance type includes a self-capacitance type, a mutual capacitance type, etc. The mutual capacitance type is preferable because it enables simultaneous multi-point detection.

[0148] The touch panel of one embodiment of the present invention can have various configurations, such as a configuration in which a display device and a detector element that are separately manufactured are bonded to each other, or a configuration in which electrodes that constitute a detector element are provided on one or both of a substrate supporting a display element and an opposing substrate.

[0149] As described above, the display device of the present embodiment can be manufactured by mounting an LED package on a substrate on which a plurality of transistors are formed, which reduces the difficulty of manufacturing the display device and improves the yield. In addition, by combining a micro LED and a transistor using a metal oxide, a display device with reduced power consumption can be realized.

[0150] In addition, since the size of a transistor can be reduced in the display device of this embodiment mode, the display device can easily be applied to electronic devices having high resolution and relatively small display portions.

[0151] This embodiment mode can be combined with other embodiment modes as appropriate. In addition, in the case where a plurality of configuration examples are shown in one embodiment mode in this specification, the configuration examples can be combined as appropriate.

[0152] (Embodiment 2) In this embodiment, a pixel of a display device according to one embodiment of the present invention will be described with reference to FIG.

[0153] [Pixels] The display device of this embodiment has a plurality of pixels arranged in a matrix of m rows and n columns (m and n are each an integer equal to or greater than 1). Fig. 7 shows an example of a circuit diagram of pixel 200(i,j) (i is an integer equal to or greater than 1 and equal to or less than m, and j is an integer equal to or greater than 1 and equal to or less than n).

[0154] A pixel 200(i,j) shown in FIG. 7 includes a light emitting element 210, a switch SW21, a switch SW22, a transistor M, and a capacitor C1.

[0155] In this embodiment, an example in which a transistor is used as the switch SW21 will be described. The gate of the switch SW21 is electrically connected to the scan line GL1(i). One of the source and drain of the switch SW21 is electrically connected to the signal line SL(j), and the other is electrically connected to the gate of the transistor M.

[0156] In this embodiment, an example in which a transistor is used as the switch SW22 will be described. A gate of the switch SW22 is electrically connected to the scan line GL2(i). One of the source and drain of the switch SW22 is electrically connected to the wiring COM, and the other is electrically connected to the gate of the transistor M.

[0157] The gate of the transistor M is electrically connected to one electrode of the capacitance element C1, the other of the source and drain of the switch SW21, and the other of the source and drain of the switch SW22. One of the source and drain of the transistor M is electrically connected to the wiring CATHODE, and the other is electrically connected to the cathode of the light-emitting element 210.

[0158] The other electrode of the capacitance element C1 is electrically connected to the wiring CATHODE.

[0159] The anode of the light emitting element 210 is electrically connected to the wiring ANODE.

[0160] The scanning line GL1(i) has a function of supplying a selection signal. The scanning line GL2(i) has a function of supplying a control signal. The signal line SL(j) has a function of supplying an image signal. A constant potential is supplied to the wiring VCOM, the wiring CATHODE, and the wiring ANODE. The anode side of the light-emitting element 210 can be set to a high potential, and the cathode side can be set to a lower potential than the anode side.

[0161] The switch SW21 is controlled by a selection signal and functions as a selection transistor for controlling the selection state of the pixel 200.

[0162] The transistor M functions as a drive transistor that controls the current flowing through the light-emitting element 210 according to the potential supplied to the gate. When the switch SW21 is in a conductive state, an image signal supplied to the signal line SL(j) is supplied to the gate of the transistor M, and the emission brightness of the light-emitting element 210 can be controlled according to the potential.

[0163] The switch SW22 has a function of controlling, based on a control signal, the gate potential of the transistor M. Specifically, the switch SW22 can supply, to the gate of the transistor M, a potential that puts the transistor M into a non-conductive state.

[0164] The switch SW22 can be used to control, for example, a pulse width, and can supply a current from the transistor M to the light emitting element 210 during a period based on a control signal. Alternatively, the light emitting element 210 can express a gray scale based on an image signal and a control signal.

[0165] Here, it is preferable that the transistors included in the pixel 200(i,j) are transistors using a metal oxide (oxide semiconductor) for a semiconductor layer in which a channel is formed.

[0166] A transistor using a metal oxide, which has a wider band gap and a lower carrier density than silicon, can achieve an extremely small off-state current. Therefore, the small off-state current allows a charge stored in a capacitor connected in series with the transistor to be held for a long period of time. Therefore, it is preferable to use transistors using an oxide semiconductor, particularly for the switch SW21 and the switch SW22 connected in series with the capacitor C1. In addition, by using transistors using an oxide semiconductor for other transistors as well, manufacturing costs can be reduced.

[0167] Furthermore, a transistor in which silicon is used as a semiconductor in which a channel is formed can also be used as the transistor included in the pixel 200(i,j). In particular, by using silicon with high crystallinity such as single crystal silicon or polycrystalline silicon, it is preferable to realize high field effect mobility and enable faster operation.

[0168] Alternatively, a structure may be used in which one or more of the transistors included in the pixel 200(i,j) include an oxide semiconductor and the remaining transistors include silicon.

[0169] Although the transistors are shown as n-channel transistors in FIG. 7, p-channel transistors can also be used.

[0170] [Transistor] Next, a transistor that can be used in a display device will be described.

[0171] The structure of the transistor included in the display device is not particularly limited. For example, the transistor may be a planar type transistor, a staggered type transistor, or an inverted staggered type transistor. In addition, the transistor may have either a top gate structure or a bottom gate structure. Alternatively, gate electrodes may be provided above and below a channel.

[0172] For example, a transistor including a metal oxide in a channel formation region can be used as a transistor included in a display device, which can have an extremely small off-state current.

[0173] Alternatively, a transistor having silicon in a channel formation region may be used as a transistor included in a display device, for example, a transistor having amorphous silicon, a transistor having crystalline silicon (typically, low-temperature polysilicon), a transistor having single crystal silicon, or the like.

[0174] [Metal oxides] Metal oxides that can be used for the semiconductor layer will be described below.

[0175] The metal oxide preferably contains at least indium or zinc. In particular, it is preferable that the metal oxide contains indium and zinc. In addition to these, it is preferable that the metal oxide contains aluminum, gallium, yttrium, tin, etc. In addition, it may contain one or more elements selected from boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, etc.

[0176] Here, the case where the metal oxide is an In-M-Zn oxide having indium, an element M, and zinc is considered. The element M is aluminum, gallium, yttrium, tin, or the like. Other elements applicable to the element M include boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, and the like. However, there are cases where the element M may be a combination of a plurality of the above-mentioned elements.

[0177] The metal oxide film can be formed by a sputtering method, or a PLD method, a PECVD method, a thermal CVD method, an ALD method, a vacuum deposition method, or the like.

[0178] In this specification and the like, metal oxides containing nitrogen may also be collectively referred to as metal oxides. Metal oxides containing nitrogen may also be referred to as metal oxynitrides. For example, metal oxides containing nitrogen, such as zinc oxynitride (ZnON), may be used for the semiconductor layer.

[0179] In this specification, etc., the term CAAC (c-axis aligned crystal) and CAC (Cloud-Aligned Composite) may be used. CAAC represents an example of a crystal structure, and CAC represents an example of a function or material configuration.

[0180] For example, a cloud-aligned composite (CAC)-OS can be used for the semiconductor layer.

[0181] CAC-OS or CAC-metal oxide has a conductive function in a part of the material and an insulating function in a part of the material, and has a function as a semiconductor as a whole. When CAC-OS or CAC-metal oxide is used in a semiconductor layer of a transistor, the conductive function is a function of flowing electrons (or holes) that become carriers, and the insulating function is a function of not flowing electrons that become carriers. By making the conductive function and the insulating function act complementarily, it is possible to impart a switching function (on / off function) to CAC-OS or CAC-metal oxide. By separating the respective functions in CAC-OS or CAC-metal oxide, it is possible to maximize both functions.

[0182] Moreover, the CAC-OS or CAC-metal oxide has a conductive region and an insulating region. The conductive region has the above-mentioned conductive function, and the insulating region has the above-mentioned insulating function. In addition, in the material, the conductive region and the insulating region may be separated at the nanoparticle level. In addition, the conductive region and the insulating region may be unevenly distributed in the material. In addition, the conductive region may be observed to be connected in a cloud shape with a blurred periphery.

[0183] In addition, in the CAC-OS or CAC-metal oxide, the conductive regions and the insulating regions may each be dispersed in the material with a size of 0.5 nm to 10 nm, preferably 0.5 nm to 3 nm.

[0184] In addition, the CAC-OS or CAC-metal oxide is composed of components having different band gaps. For example, the CAC-OS or CAC-metal oxide is composed of a component having a wide gap due to an insulating region and a component having a narrow gap due to a conductive region. In this configuration, when carriers are caused to flow, the carriers mainly flow in the component having the narrow gap. In addition, the component having the narrow gap acts complementarily on the component having the wide gap, and carriers also flow in the component having the wide gap in conjunction with the component having the narrow gap. Therefore, when the above CAC-OS or CAC-metal oxide is used in the channel formation region of a transistor, a high current driving force in the on state of the transistor, that is, a large on-current and a high field effect mobility can be obtained.

[0185] That is, CAC-OS or CAC-metal oxide can also be called a matrix composite or a metal matrix composite.

[0186] Oxide semiconductors (metal oxides) are classified into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors, such as c-axis aligned crystalline oxide semiconductors (CAAC-OS), polycrystalline oxide semiconductors, nanocrystalline oxide semiconductors (nc-OS), amorphous-like oxide semiconductors (a-like OS), and amorphous oxide semiconductors.

[0187] CAAC-OS has a c-axis orientation and a distorted crystal structure in which multiple nanocrystals are connected in the ab-plane direction. The distortion refers to a portion where the lattice orientation changes between a region with a uniform lattice arrangement and a region with a different uniform lattice arrangement in the region where multiple nanocrystals are connected.

[0188] Nanocrystals are basically hexagonal, but may be non-regular hexagonal. In addition, the lattice arrangement may be pentagonal or heptagonal due to the distortion. In CAAC-OS, it is difficult to confirm clear grain boundaries even in the vicinity of the distortion. In other words, it is found that the formation of grain boundaries is suppressed by the distortion of the lattice arrangement. This is because CAAC-OS can tolerate distortion due to the fact that the arrangement of oxygen atoms in the ab-plane direction is not dense and the bond distance between atoms changes due to the substitution of metal elements.

[0189] CAAC-OS also tends to have a layered crystal structure (also referred to as a layered structure) in which a layer containing indium and oxygen (hereinafter, In layer) and a layer containing element M, zinc, and oxygen (hereinafter, (M, Zn) layer) are stacked. Note that indium and element M can be substituted for each other, and when element M in an (M, Zn) layer is substituted for indium, it can also be represented as an (In, M, Zn) layer. When indium in an In layer is substituted for element M, it can also be represented as an (In, M) layer.

[0190] CAAC-OS is a metal oxide with high crystallinity. On the other hand, it is difficult to confirm clear crystal boundaries in CAAC-OS, so it is said that the decrease in electron mobility caused by crystal boundaries is unlikely to occur. In addition, since the crystallinity of metal oxides can be decreased by the inclusion of impurities or the generation of defects, CAAC-OS is unlikely to have impurities or defects (oxygen vacancies (V O : It is also called oxygen vacancy. ) Therefore, metal oxides with CAAC-OS have stable physical properties. Therefore, metal oxides with CAAC-OS are resistant to heat and highly reliable.

[0191] The nc-OS has periodic atomic arrangement in a microscopic region (for example, a region of 1 nm to 10 nm, particularly a region of 1 nm to 3 nm). In addition, the nc-OS does not show regularity in the crystal orientation between different nanocrystals. Therefore, no orientation is seen 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.

[0192] Indium-gallium-zinc oxide (hereinafter referred to as IGZO), a type of metal oxide containing indium, gallium, and zinc, may have a stable structure when made into the above-mentioned nanocrystals. In particular, since IGZO tends to have difficulty in crystal growth in the atmosphere, it may be structurally more stable when made into small crystals (for example, the above-mentioned nanocrystals) rather than large crystals (here, crystals of several mm or several cm).

[0193] The a-like OS is a metal oxide having a structure between the nc-OS and an 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 CAAC-OS.

[0194] Oxide semiconductors (metal oxides) have a variety of structures and each structure 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, an nc-OS, and a CAAC-OS.

[0195] The metal oxide film functioning as the semiconductor layer can be formed using either one or both of an inert gas and an oxygen gas. The flow rate ratio of oxygen (oxygen partial pressure) during the formation of the metal oxide film is not particularly limited. However, in order to obtain a transistor with high field effect mobility, the flow rate ratio of oxygen (oxygen partial pressure) during the formation of the metal oxide film is preferably 0% or more and 30% or less, more preferably 5% or more and 30% or less, and even more preferably 7% or more and 15% or less.

[0196] The energy gap of the metal oxide is preferably 2 eV or more, more preferably 2.5 eV or more, and further preferably 3 eV or more. By using a metal oxide having such a wide energy gap, the off-state current of the transistor can be reduced.

[0197] This embodiment mode can be combined with other embodiment modes as appropriate.

[0198] (Embodiment 3) In this embodiment, electronic devices of one embodiment of the present invention will be described with reference to FIGS.

[0199] The electronic devices of this embodiment include the display device of one embodiment of the present invention in a display portion. The display device of one embodiment of the present invention has high display quality and low power consumption. In addition, the display device of one embodiment of the present invention can be easily made large and highly precise. Therefore, the display device can be used in the display portion of various electronic devices.

[0200] Examples of electronic devices include electronic devices with relatively large screens, such as television sets, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and audio playback devices.

[0201] In particular, the display device of one embodiment of the present invention can be suitably used in electronic devices having a relatively small display area because it can increase the resolution. Examples of such electronic devices include wristwatch-type or bracelet-type information terminals (wearable devices), head-mounted wearable devices such as VR (Virtual Reality) devices, glasses-type AR (Augmented Reality) devices, and MR (Mixed Reality) devices.

[0202] The electronic device of this embodiment may have a sensor (including a function to measure force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays).

[0203] The electronic device of the present embodiment can have various functions, such as a function of displaying various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function of displaying a calendar, date, time, etc., a function of executing various software (programs), a wireless communication function, a function of reading out a program or data recorded on a recording medium, etc.

[0204] 8A shows a perspective view of a glasses-type electronic device 900. The electronic device 900 includes a pair of display panels 901, a pair of housings 902, a pair of optical members 903, a pair of mounting units 904, and the like.

[0205] The electronic device 900 can project an image displayed on the display panel 901 onto a display area 906 of the optical member 903. Since the optical member 903 is translucent, the user can see the image displayed in the display area 906 superimposed on a transmitted image visually recognized through the optical member 903. Therefore, the electronic device 900 is an electronic device capable of AR display.

[0206] The display panel 901 included in the electronic device 900 preferably has an image capturing function in addition to a function of displaying an image. In this case, the electronic device 900 can receive light incident on the display panel 901 via the optical member 903, convert it into an electrical signal, and output it. This allows an image of the user's eye or the eye and its surroundings to be captured and output as image information to the outside or to a calculation unit included in the electronic device 900.

[0207] One of the housings 902 is provided with a camera 905 capable of capturing an image of the front. Although not shown, one of the housings 902 is provided with a connector to which a wireless receiver or a cable can be connected, and a video signal or the like can be supplied to the housing 902. By providing an acceleration sensor such as a gyro sensor in the housing 902, the direction of the user's head can be detected and an image corresponding to the direction can be displayed in the display area 906. The housing 902 is preferably provided with a battery, which is preferably capable of being charged wirelessly or by wire.

[0208] 8B, a method of projecting an image onto a display area 906 of the electronic device 900 will be described. A display panel 901, a lens 911, and a reflector 912 are provided inside a housing 902. In addition, a portion of an optical member 903 that corresponds to the display area 906 has a reflecting surface 913 that functions as a half mirror.

[0209] Light 915 emitted from the display panel 901 passes through the lens 911 and is reflected by the reflector 912 towards the optical member 903. Inside the optical member 903, the light 915 is repeatedly totally reflected at the end face of the optical member 903 and reaches the reflecting surface 913, whereby an image is projected onto the reflecting surface 913. This allows the user to visually recognize both the light 915 reflected by the reflecting surface 913 and the transmitted light 916 that has passed through the optical member 903 (including the reflecting surface 913).

[0210] 8 shows an example in which the reflector 912 and the reflecting surface 913 each have a curved surface. This allows for greater freedom in optical design and allows for a thinner optical member 903 than when these surfaces are flat. The reflector 912 and the reflecting surface 913 may also be flat.

[0211] A member having a mirror surface can be used as the reflector 912, and it is preferable that the reflector has a high reflectance. Also, a half mirror utilizing the reflection of a metal film may be used as the reflector surface 913, but the transmittance of the transmitted light 916 can be increased by using a prism utilizing total reflection or the like.

[0212] Here, the electronic device 900 preferably has a mechanism for adjusting one or both of the distance and angle between the lens 911 and the display panel 901. This makes it possible to adjust the focus and enlarge or reduce the image. For example, the lens 911 and / or the display panel 901 may be configured to be movable in the optical axis direction.

[0213] It is preferable that the electronic device 900 has a mechanism capable of adjusting the angle of the reflector 912. It is possible to change the position of the display area 906 where an image is displayed by changing the angle of the reflector 912. This makes it possible to position the display area 906 at an optimal position according to the position of the user's eyes.

[0214] The display device of one embodiment of the present invention can be applied to the display panel 901. Thus, the electronic device 900 can provide an extremely high-definition display.

[0215] 9(A) and (B) show perspective views of a goggle-type electronic device 950. Fig. 9(A) is a perspective view showing the front, top, and left side of the electronic device 950, and Fig. 9(B) is a perspective view showing the back, bottom, and right side of the electronic device 950.

[0216] The electronic device 950 includes a pair of display panels 951, a housing 952, a pair of mounting portions 954, a cushioning member 955, and a pair of lenses 956. The pair of display panels 951 are provided inside the housing 952 at positions viewable through the lenses 956.

[0217] The electronic device 950 is an electronic device for VR. A user wearing the electronic device 950 can view an image displayed on a display panel 951 through a lens 956. In addition, by displaying different images on a pair of display panels 951, a three-dimensional display using parallax can be performed.

[0218] An input terminal 957 and an output terminal 958 are provided on the rear side of the housing 952. A cable for supplying a video signal from a video output device or the like, or power for charging a battery provided within the housing 952, can be connected to the input terminal 957. The output terminal 958 can function as, for example, an audio output terminal, and can be connected to earphones, headphones, or the like. Note that, in the case of a configuration capable of outputting audio data via wireless communication or in the case of outputting audio from an external video output device, the audio output terminal does not need to be provided.

[0219] The electronic device 900 preferably has a mechanism for adjusting the left-right positions of the lens 956 and the display panel 951 so that the lens 956 and the display panel 951 are positioned optimally according to the position of the user's eyes. Also, the electronic device 900 preferably has a mechanism for adjusting the focus by changing the distance between the lens 956 and the display panel 951.

[0220] The display device of one embodiment of the present invention can be applied to the display panel 951. Therefore, the electronic device 950 can display images with extremely high definition. This allows the user to feel a high sense of immersion.

[0221] The cushioning member 955 is a portion that comes into contact with the user's face (forehead, cheeks, etc.). The cushioning member 955 comes into close contact with the user's face, thereby preventing light leakage and enhancing the sense of immersion. The cushioning member 955 is preferably made of a soft material so that it comes into close contact with the user's face when the user wears the electronic device 950. For example, materials such as rubber, silicone rubber, urethane, and sponge can be used. In addition, if a material such as sponge with a surface covered with cloth or leather (natural leather or synthetic leather) is used as the cushioning member 955, it is difficult for a gap to occur between the user's face and the cushioning member 955, and light leakage can be suitably prevented. It is preferable that the members that come into contact with the user's skin, such as the cushioning member 955 and the mounting portion 954, are configured to be removable, since this makes cleaning and replacement easy.

[0222] An electronic device 6500 shown in FIG. 10A is a portable information terminal that can be used as a smartphone.

[0223] The electronic device 6500 includes a housing 6501, a display portion 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, and a light source 6508. The display portion 6502 has a touch panel function.

[0224] The display device of one embodiment of the present invention can be applied to the display portion 6502.

[0225] FIG. 10B is a schematic cross-sectional view including the end portion of the housing 6501 on the microphone 6506 side.

[0226] A light-transmitting protective member 6510 is provided on the display surface side of the housing 6501, and a display panel 6511, optical members 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are arranged in the space surrounded by the housing 6501 and the protective member 6510.

[0227] A display panel 6511, an optical member 6512, and a touch sensor panel 6513 are fixed to the protective member 6510 by an adhesive layer (not shown).

[0228] In an area outside the display unit 6502, a part of the display panel 6511 is folded back, and the folded back part is connected to an FPC 6515. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to a terminal provided on a printed circuit board 6517.

[0229] The flexible display of one embodiment of the present invention can be applied to the display panel 6511. Therefore, an extremely lightweight electronic device can be realized. In addition, since the display panel 6511 is extremely thin, a large-capacity battery 6518 can be mounted thereon while suppressing the thickness of the electronic device. In addition, by folding back a part of the display panel 6511 and arranging a connection portion with the FPC 6515 on the back side of the pixel portion, an electronic device with a narrow frame can be realized.

[0230] 11A shows an example of a television set. In a television set 7100, a display portion 7000 is incorporated in a housing 7101. Here, the housing 7101 is supported by a stand 7103.

[0231] The display device of one embodiment of the present invention can be applied to the display portion 7000.

[0232] 11A can be operated using an operation switch provided on the housing 7101 or a separate remote control 7111. Alternatively, the display portion 7000 may be provided with a touch sensor, and the television set 7100 may be operated by touching the display portion 7000 with a finger or the like. The remote control 7111 may have a display portion that displays information output from the remote control 7111. Using an operation key or a touch panel provided on the remote control 7111, a channel and a volume can be operated, and an image displayed on the display portion 7000 can be operated.

[0233] The television device 7100 includes a receiver and a modem. The receiver can receive general television broadcasts. By connecting to a wired or wireless communication network via the modem, one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers) information communication can be performed.

[0234] 11B shows an example of a laptop personal computer 7200. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, an external connection port 7214, and the like. A display portion 7000 is incorporated in the housing 7211.

[0235] The display device of one embodiment of the present invention can be applied to the display portion 7000.

[0236] Figures 11(C) and (D) show an example of digital signage.

[0237] 11C includes a housing 7301, a display portion 7000, and a speaker 7303. The digital signage 7300 may further include an LED lamp, an operation key (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0238] 11D shows a digital signage 7400 attached to a cylindrical pillar 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.

[0239] In FIGS. 11C and 11D, the display device of one embodiment of the present invention can be applied to the display portion 7000.

[0240] The larger the display unit 7000, the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it catches people's attention, which can increase the advertising effect of, for example, advertisements.

[0241] Applying a touch panel to the display unit 7000 is preferable because it not only displays images or videos on the display unit 7000 but also allows the user to intuitively operate it. Furthermore, when used for providing information such as route information or traffic information, usability can be improved by intuitive operation.

[0242] 11C and 11D, the digital signage 7300 or the digital signage 7400 is preferably capable of wirelessly linking with an information terminal 7311 or an information terminal 7411 such as a smartphone carried by a user. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411. By operating the information terminal 7311 or the information terminal 7411, the display on the display unit 7000 can be switched.

[0243] In addition, a game can be executed on the digital signage 7300 or the digital signage 7400 using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller). This allows an unspecified number of users to participate in and enjoy the game at the same time.

[0244] The electronic devices shown in Figures 12(A) to 12(F) have 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 of measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor or infrared rays), a microphone 9008, etc.

[0245] 12(A) to 12(F) have various functions. For example, the electronic devices may have a function of displaying various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function of displaying a calendar, date, or time, a function of controlling processing by various software (programs), a wireless communication function, a function of reading and processing a program or data recorded on a recording medium, and the like. Note that the functions of the electronic devices are not limited to these, and the electronic devices may have various functions. The electronic devices may have multiple display units. In addition, the electronic devices may have a function of providing a camera or the like to capture still images or videos and store them on a recording medium (external or built-in to the camera), a function of displaying the captured images on the display unit, and the like.

[0246] The electronic devices shown in FIGS. 12A to 12F will be described in detail below.

[0247] FIG. 12A is a perspective view showing a mobile information terminal 9101. The mobile information terminal 9101 can be used as, for example, a smartphone. Note that the mobile information terminal 9101 may be provided with a speaker 9003, a connection terminal 9006, a sensor 9007, and the like. The mobile information terminal 9101 can display text and image information on a plurality of surfaces. FIG. 12A shows an example in which three icons 9050 are displayed. Information 9051 shown in a dashed rectangle can also be displayed on another surface of the display unit 9001. Examples of the information 9051 include notifications of incoming e-mail, SNS, and phone calls, titles of e-mail and SNS, sender names, date and time, time, remaining battery level, and antenna reception strength. Alternatively, the icon 9050 or the like may be displayed at the position where the information 9051 is displayed.

[0248] 12(B) is a perspective view showing a mobile information terminal 9102. The mobile information terminal 9102 has a function of displaying information on three or more surfaces of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different surfaces. For example, a user can check information 9053 displayed in a position that can be observed from above the mobile information terminal 9102 while the user holds the mobile information terminal 9102 in a breast pocket of a suit. The user can check the display without taking the mobile information terminal 9102 out of the pocket and determine, for example, whether to answer a call.

[0249] 12C is a perspective view showing a wristwatch-type mobile information terminal 9200. The mobile information terminal 9200 can be used as, for example, a smart watch. The display surface of the display unit 9001 is curved, and display can be performed along the curved display surface. The mobile information terminal 9200 can also perform hands-free conversation by communicating with, for example, a headset capable of wireless communication. The mobile information terminal 9200 can also perform data transmission and charging with another information terminal through a connection terminal 9006. Note that charging may be performed by wireless power supply.

[0250] 12D, 12E, and 12F are perspective views showing a foldable mobile information terminal 9201. FIG. 12D shows the mobile information terminal 9201 in an unfolded state, FIG. 12F shows the mobile information terminal 9201 in a folded state, and FIG. 12E shows the mobile information terminal 9201 in a state in the middle of changing from one of FIG. 12D and FIG. 12F to the other. The mobile information terminal 9201 is highly portable when folded, and is highly viewable due to a seamless wide display area when unfolded. A display unit 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by a hinge 9055. For example, the display unit 9001 can be bent with a curvature radius of 0.1 mm or more and 150 mm or less.

[0251] This embodiment mode can be appropriately combined with other embodiment modes and examples. EXAMPLES

[0252] In this example, the results of manufacturing a display device according to one embodiment of the present invention will be described.

[0253] In this example, an active matrix display device was fabricated having a display area with a diagonal size of 2.23 inches, an effective pixel count of 20×20, and a pixel size of 2000 μm×2000 μm (mounting pitch of the LED package).

[0254] The display element used a 1 mm square LED package containing three mini LED chips of red, green, and blue colors.

[0255] The transistors used in this study are self-aligned top gate self-alignment (TGSA) transistors that use crystalline metal oxide as the semiconductor layer. The metal oxide used is In-Ga-Zn oxide.

[0256] The gate driver and source driver were not built in.

[0257] The pixel circuit of the display device of this embodiment corresponds to the pixel circuit shown in FIG.

[0258] The display device of this embodiment has the top view structure shown in Figures 1(A) to (C) and the cross-sectional structure shown in Figures 2(A) to (C) and 3(A) to (C). Note that the insulating layer 104 and the resin 129 are not provided.

[0259] A glass substrate was used for the substrate 102. A laminated structure of a titanium film having a thickness of about 100 nm, an aluminum film having a thickness of about 400 nm, and a titanium film having a thickness of about 100 nm was used for the conductive layers 131R, 131G, 131B, and 132. That is, in each of the conductive layers 131R, 131G, 131B, and 132, the layer in contact with the conductor 133 is a titanium film. An acrylic film having a thickness of about 2 μm was used for the protective layer 128.

[0260] After forming a laminated structure from the transistor 120 to the protective layer 128 on the substrate 102, silver paste was applied as the conductor 133 onto the conductive layer 131R, the conductive layer 131G, the conductive layer 131B, and the conductive layer 132, and the LED package 150 was mounted.

[0261] FIG. 13 shows a display photograph of the display device of this embodiment.

[0262] As described above, in this example, an active matrix display device was fabricated by mounting an LED package on a substrate on which a transistor using a metal oxide as a semiconductor layer was formed. As shown in Fig. 13, the display device fabricated in this example provided good display results. [Explanation of symbols]

[0263] C1: Capacitive element, GL1: Scanning line, GL2: Scanning line, SW21: Switch, SW22: Switch, 100: Display device, 100A: Display device, 101: Substrate, 102: Substrate, 103: Electrode, 104: Insulating layer, 106: Electrode, 108: Wiring, 109: Circuit, 110: Display unit, 111: Semiconductor layer, 112: Electrode, 113: Light-emitting layer, 114: Semiconductor layer, 115: Electrode, 116: Electrode, 117: Semiconductor layer, 118: Light-emitting layer, 119: Semiconductor layer, 120: Transistor, 120A: Transistor, 120B: Transistor, 120C: Transistor, 121: Conductive layer, 1 22: insulating layer, 123: metal oxide layer, 123i: channel formation region, 123n: low resistance region, 124: insulating layer, 124a: insulating layer, 124b: insulating layer, 125: conductive layer, 126a: conductive layer, 126b: conductive layer, 127: insulating layer, 128: protective layer, 129: resin, 130: pixel, 131B: conductive layer, 131G: conductive layer, 131R: conductive layer, 132: conductive layer, 133: conductor, 141: substrate, 142: case, 143: wire, 144: wire, 145: sealing layer, 146: adhesive layer, 147: color conversion layer, 150: LED package, 151: substrate, 151B: blue color LED chip, 151G: green LED chip, 151R: red LED chip, 152B: electrode, 152G: electrode, 152R: electrode, 153: electrode, 154: heat sink, 155: LED package, 161: conductive layer, 162: insulating layer, 163: insulating layer, 164: insulating layer, 165: metal oxide layer, 166: conductive layer, 167: insulating layer, 168: conductive layer, 171: insulating layer, 172: conductive layer, 173: insulating layer, 174: substrate, 175: insulating layer, 181: insulating layer, 182: insulating layer, 183: insulating layer, 184a: conductive layer, 184b: conductive layer, 185: insulating layer, 186: insulating layer, 187: conductive layer, 188: insulating layer, 189: conductive layer, 190: transistor, 191: substrate, 192: element isolation layer, 193: low resistance region, 194: insulating layer, 195: conductive layer, 196: insulating layer, 198: conductive layer, 199: insulating layer, 200: pixel, 210: light emitting element, 900: electronic device, 901: display panel, 902: housing, 903: optical member, 904: mounting part, 905: camera, 906: display area, 911: lens, 912: reflector, 913: reflecting surface, 915: light, 916: transmitted light, 950: electronic device, 951: display panel, 952: housing,954: mounting part, 955: cushioning member, 956: lens, 957: input terminal, 958: output terminal, 6500: electronic device, 6501: housing, 6502: display unit, 6503: power button, 6504: button, 6505: speaker, 6506: microphone, 6507: camera, 6508: light source, 6510: protective member, 6511: display panel, 6512: optical member, 6513: touch sensor panel, 6515: FPC, 6516: IC, 6517: printed circuit board, 6518: battery, 7000: display unit, 7100: television device, 7101: housing, 7103: stand, 7111: remote control unit, 7200: notebook personal computer, 7211 : Housing, 7212: Keyboard, 7213: Pointing device, 7214: External connection port, 7300: Digital signage, 7301: Housing, 7303: Speaker, 7311: Information terminal, 7400: Digital signage, 7401: Pillar, 7411: Information terminal, 9000: Housing, 9001: Display, 9003: Speaker, 9005: Operation key, 9006: Connection terminal, 9007: Sensor, 9008: Microphone, 9050: Icon, 9051: Information, 9052: Information, 9053: Information, 9054: Information, 9055: Hinge, 9101: Portable information terminal, 9102: Portable information terminal, 9200: Portable information terminal, 9201: Portable information terminal,

Claims

1. A pixel having: the pixel includes a first transistor, a second transistor, and a light emitting diode package; each of the first transistor and the second transistor has a channel formation region formed of an oxide semiconductor containing In, Ga, and Zn; the light emitting diode package includes first to third light emitting diodes, first to third conductive layers, and first to third wires; one of a source and a drain of the first transistor is electrically connected to a first electrode of the first light-emitting diode through the first conductive layer; one of a source and a drain of the second transistor is electrically connected to a second electrode of the second light-emitting diode through the second conductive layer; the third conductive layer is electrically connected to the first electrode via the first wire; the third conductive layer is electrically connected to the second electrode via the second wire; The third conductive layer is electrically connected to a third electrode of the third light-emitting diode via the third wire.

2. A pixel having: The pixel includes first to third transistors, a light emitting diode package, and an insulating layer; each of the first transistor and the second transistor has an oxide semiconductor containing In, Ga, and Zn in a channel formation region and is provided above the insulating layer; the third transistor has silicon in a channel formation region and is provided below the insulating layer; the light emitting diode package includes first to third light emitting diodes, first to third conductive layers, and first to third wires; one of a source and a drain of the first transistor is electrically connected to a first electrode of the first light-emitting diode through the first conductive layer; one of a source and a drain of the second transistor is electrically connected to a second electrode of the second light-emitting diode through the second conductive layer; the third conductive layer is electrically connected to the first electrode via the first wire; the third conductive layer is electrically connected to the second electrode via the second wire; The third conductive layer is electrically connected to a third electrode of the third light-emitting diode via the third wire.

Images