Indication device

Abstract

To provide a liquid crystal display device with a high aperture ratio. To provide a liquid crystal display device with low power consumption. . A display device includes a transistor and a capacitor. The transistor includes a first an insulating layer, a first semiconductor layer in contact with the first insulating layer, and a second insulating layer in contact with the first semiconductor layer; The insulating layer is electrically connected to the first semiconductor layer through an opening provided in the second insulating layer. a first conductive layer, and the first semiconductor layer has a channel region. a second conductive layer in contact with the insulating layer; a second insulating layer in contact with the second conductive layer; a first conductive layer in contact with the first semiconductor layer, and the second conductive layer has a composition similar to that of the first semiconductor layer. The first conductive layer and the second conductive layer have the function of transmitting visible light.

Description

[Technical Field]

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

[0002] Note that one embodiment of the present invention is not limited to the above technical field. Examples of the semiconductor device include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, an electronic device, a lighting device, Input devices (e.g., touch sensors, etc.), input / output devices (e.g., touch panels, etc.), A driving method or a manufacturing method thereof can be given as an example. [Background technology]

[0003] It is used in many flat panel displays such as liquid crystal displays and light emitting displays. The transistors used are made of amorphous silicon, single crystal silicon, or silicon nitride formed on a glass substrate. Alternatively, the semiconductor device is made of a silicon semiconductor such as polycrystalline silicon. Transistors that use conductors are also used in integrated circuits (ICs).

[0004] In recent years, metal oxides that exhibit semiconducting properties have been used in transistors instead of silicon semiconductors. In this specification, metal oxides that exhibit semiconducting properties are referred to as oxide semiconductors. For example, Patent Documents 1 and 2 describe oxide semiconductors such as a transistor using a semiconductor material, zinc oxide, or In-Ga-Zn-based oxide; A technique for using a transistor as a switching element for a pixel of a display device has been disclosed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-123861 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-96055 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of one embodiment of the present invention is to provide a liquid crystal display device with a high aperture ratio and a manufacturing method thereof. Another embodiment of the present invention is a liquid crystal display device and a display device having a simplified manufacturing process. Another object of the present invention is to provide a manufacturing method thereof. Another object of the present invention is to provide a liquid crystal display device and a manufacturing method thereof. An object of the present invention is to provide a high-definition liquid crystal display device and a manufacturing method thereof. Another embodiment of the present invention is to provide a highly reliable liquid crystal display device and a manufacturing method thereof. Another object of one embodiment of the present invention is to provide a novel liquid crystal display device and a manufacturing method thereof. One of the purposes is to provide the following.

[0007] Note that the description of these problems does not preclude the existence of other problems. It is not necessary to solve all of these problems. From the description of the section, it is possible to extract other issues. [Means for solving the problem]

[0008] One embodiment of the present invention is a display device including a transistor and a capacitor, The photoresist includes a first insulating layer, a first semiconductor layer in contact with the first insulating layer, and a second semiconductor layer in contact with the first semiconductor layer. and a second insulating layer electrically connected to the first semiconductor layer through an opening provided in the second insulating layer. a first conductive layer electrically connected to the first semiconductor layer, the first semiconductor layer having a channel region and a capacitance The element includes a second conductive layer in contact with the first insulating layer, a second insulating layer in contact with the second conductive layer, and a first conductive layer in contact with the second insulating layer, the second conductive layer being similar to the first semiconductor layer; The first conductive layer and the second conductive layer have a composition of the above, and the first conductive layer and the second conductive layer have a function of transmitting visible light. It is a display device.

[0009] In the above embodiment, the first semiconductor layer, the first conductive layer, and the second conductive layer are made of metal. It may have an oxide.

[0010] In the above embodiment, the metal oxide contained in the first semiconductor layer is The metal oxide may contain one or more metal elements.

[0011] In the above embodiment, the first conductive layer may include In—Zn oxide.

[0012] In the above embodiment, the second insulating layer may include silicon oxynitride.

[0013] In the above embodiment, the second insulating layer and the third insulating layer are in contact with the first conductive layer. The third insulating layer may have more oxygen than the stoichiometric amount.

[0014] In the above-mentioned embodiment, the liquid crystal element has a liquid crystal layer and a pixel electrode. The pixel electrode may be electrically connected to the first conductive layer.

[0015] In the above embodiment, the resistivity of the liquid crystal element is 1.0×10 14 Ω·cm or more Good too.

[0016] In the above aspect, the frame frequency of the display device is 0.1 Hz or more and less than 60 Hz. After writing data to the capacitor, the display device turns off the transistor. The memory may have a function of retaining data by doing so.

[0017] In the above aspect, the frame frequency of the display device is 0.1 Hz or more and less than 20 Hz. It's okay to have one.

[0018] In the above-mentioned aspect, the scanning line is formed using a metal material, and the scanning line may have a portion that overlaps with the channel region of the transistor.

[0019] Further, an electronic device including the display device of one embodiment of the present invention and an operation key is also an embodiment of the present invention. is.

[0020] Another embodiment of the present invention is a manufacturing method of a display device, the manufacturing method including: forming a first semiconductor layer and a second semiconductor layer; and forming a second semiconductor layer so as to be in contact with the first semiconductor layer and the second semiconductor layer. The first insulating layer is formed so as to have a first insulating film extending to the first semiconductor layer. forming an opening; and forming a first semiconductor layer through the first opening, the first semiconductor layer overlapping the second semiconductor layer. forming a third semiconductor layer in electrical contact with the first insulating layer and forming a second insulating layer in contact with the third semiconductor layer; forming a second opening reaching the third semiconductor layer through the second opening; forming a pixel electrode so as to be electrically connected to the first insulating layer; In the step of forming the first semiconductor layer and the second semiconductor layer, the resistance of each of the first semiconductor layer and the second semiconductor layer is reduced. In the step of forming the second insulating layer, the third semiconductor layer is made to have a low resistance, and the second insulating layer is made to have a low resistance. After the formation of the layer, the channel region of the first semiconductor layer, which has been made to have a low resistance, is made to have a high resistance. This is a method for producing the above.

[0021] The first semiconductor layer, the second semiconductor layer, and the third semiconductor layer may also be formed to have a metal oxide. A body layer may be formed.

[0022] The third semiconductor layer may also be formed to include In-Zn oxide.

[0023] In addition, the first insulating layer and the second insulating layer are formed by a CVD method using a film-forming gas containing silane. A layer may be formed.

[0024] The deposition gas may also contain nitrogen oxides.

[0025] After the second insulating layer is formed, a heat treatment may be performed.

[0026] Furthermore, the liquid crystal layer may be formed after the pixel electrodes are formed. [Effects of the Invention]

[0027] According to one embodiment of the present invention, a liquid crystal display device with a high aperture ratio and a manufacturing method thereof can be provided. Alternatively, according to one embodiment of the present invention, a liquid crystal display device and a liquid crystal display device having a simplified manufacturing process can be provided. According to one embodiment of the present invention, a liquid crystal display device with low power consumption can be manufactured. According to one embodiment of the present invention, a display device and a manufacturing method thereof can be provided. It is possible to provide a high-definition liquid crystal display device and a manufacturing method thereof. According to the embodiment, a highly reliable liquid crystal display device and a manufacturing method thereof can be provided. According to one embodiment of the present invention, a novel liquid crystal display device and a manufacturing method thereof can be provided. can.

[0028] The description of these effects does not preclude the existence of other effects. However, it is not necessary to have all of these effects. , it is possible to extract effects other than these. [Brief explanation of the drawings]

[0029] [Figure 1] FIG. 1 is a cross-sectional view showing an example of a display device. [Figure 2] FIG. 1 is a cross-sectional view showing an example of a display device. [Figure 3] 1A and 1B are a top view and a cross-sectional view illustrating an example of a display device. [Figure 4] FIG. 1 is a cross-sectional view showing an example of a display device. [Figure 5] FIG. 1 is a perspective 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 cross-sectional view showing an example of a display device. [Figure 8] 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing a display device. [Figure 9] 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing a display device. [Figure 10] 1A and 1B are diagrams showing examples of pixel arrangement and configuration; [Figure 11] FIG. 1 is a perspective view showing an example of a display device. [Figure 12] FIG. 1 is a cross-sectional view showing an example of a display device. [Figure 13] 1A and 1B are diagrams showing an example of the configuration and operation mode of a pixel; [Figure 14] 1A and 1B are a block diagram and a timing chart of a touch sensor; [Figure 15] 1A and 1B are a block diagram and a timing chart of a display device. [Figure 16] 1A to 1C are diagrams illustrating operations of a display device and a touch sensor. [Figure 17] 1A to 1C are diagrams illustrating operations of a display device and a touch sensor. [Figure 18] 1A and 1B are diagrams illustrating examples of electronic devices. DETAILED DESCRIPTION OF THE INVENTION

[0030] The embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the following description. The present invention may be modified in various forms and details without departing from the spirit and scope of the present invention. Therefore, the present invention is based on the following embodiments. It should not be construed as being limited to the contents of the description of the state.

[0031] In the configuration of the invention described below, the same parts or parts having similar functions are The same reference numerals are used in common between different drawings, and repeated explanations thereof will be omitted. When referring to a function, the hatch pattern may be the same and no particular symbol may be assigned.

[0032] In addition, the position, size, range, etc. of each component shown in the drawings are not necessarily the same as those in actual applications for ease of understanding. The position, size, range, etc. may not be shown. Therefore, the disclosed invention may not necessarily be The present invention is not limited to the position, size, range, etc. disclosed in the drawings.

[0033] The words "film" and "layer" may be used interchangeably depending on the situation. For example, the term "conductive layer" can be replaced with "conductive film." Alternatively, for example, the term "insulating film" can be changed to The term can be changed to "insulating layer."

[0034] In this specification, metal oxide is a broad term referring to metal oxides. Metal oxides are oxides. Metal oxides are oxide insulators and oxide conductors (including transparent oxide conductors). , oxide semiconductors (also called oxide semiconductors or simply OS), etc. For example, when a metal oxide is used in the semiconductor layer of a transistor, the metal oxide In other words, when describing an OS FET, In other words, the transistor can be a transistor including a metal oxide or an oxide semiconductor.

[0035] In this specification and the like, metal oxides containing nitrogen are also referred to as metal oxides. Nitrogen-containing metal oxides are also called metal oxynitrides (met). It may also be called hydroxybenzoxanthate (hydroxybenzoxanthate).

[0036] (Embodiment 1) In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS. .

[0037] <1. Display device configuration example 1> First, a display device of one embodiment of the present invention will be described with reference to FIGS.

[0038] A display device according to one embodiment of the present invention includes a display element, a transistor, and a capacitor. The element may be, for example, a liquid crystal element. Hereinafter, the display element will be described as a liquid crystal element. However, the display element to which one embodiment of the present invention can be applied is not limited to a liquid crystal element. The light-emitting element may be, for example, an organic EL element. Children, inorganic EL elements, LEDs (Light Emitting Diodes), QLEDs ( Quantum-dot Light Emitting Diode, semiconductor laser As the light emitting element, a backlight or a sidelight can be used. Alternatively, a light source such as a liquid crystal display (LCD) may be used in combination with a transmission type liquid crystal display. Alternatively, both a liquid crystal element and a light emitting element may be used.

[0039] The liquid crystal element includes a pixel electrode, a liquid crystal layer, and a common electrode. The pixel electrode, the common electrode, and the capacitor element are electrically connected to the pixel electrode. The visible light passes through the liquid crystal element and is emitted to the outside of the display device. do.

[0040] In a display device according to one embodiment of the present invention, a capacitor has a region that transmits visible light. The capacitance element can be provided in the display region. Therefore, the aperture ratio of the pixel can be increased, and the display device This can reduce power consumption and also realize a high-definition display device.

[0041] The transistor included in the display device of one embodiment of the present invention has a channel-protective structure. By adopting this structure, the channel protection layer of the transistor and the dielectric of the capacitor element can be This allows the layers to be formed in the same process, improving the reliability of the transistor. This can simplify the manufacturing process of the display device of one embodiment of the present invention.

[0042] The display device according to one embodiment of the present invention further includes scanning lines and signal lines. The lines are electrically connected to the transistors. The scanning lines and the signal lines are By using a metal layer for the scanning lines and signal lines, The resistance value can be reduced.

[0043] In addition, it is preferable that the scanning line has a portion overlapping with a channel region of the transistor. Depending on the material used in the channel region of a transistor, the transistor may become The scanning line has an overlap with the channel region of the transistor. This can prevent external light or backlight from irradiating the channel area. This can improve the reliability of the transistor.

[0044] The display device 10A shown in FIG. 1(A) includes a substrate 11, a substrate 12, a transistor 14, and a liquid crystal element. 15, a capacitance element 16, etc. A backlight unit is provided on the substrate 12 side of the display device 10A. 13 is placed.

[0045] The liquid crystal element 15 includes a pixel electrode 21, a liquid crystal layer 22, and a common electrode 23. 1 is electrically connected to the transistor 14 through an opening provided in the insulating layer 26. On the insulating layer 26, a film is formed using the same process and material as the pixel electrode 21. A conductive layer 25 is provided. The conductive layer 25 is electrically connected to the common electrode 23 via a connector 29. are actively connected.

[0046] Light 45a from the backlight unit 13 passes through the substrate 12, the insulating layer 26, the pixel electrodes 21, the liquid crystal display panel 22, and the liquid crystal display panel 24. The light is emitted to the outside of the display device 10A through the crystal layer 22, the common electrode 23, and the substrate 11. The materials of these layers through which the light 45a passes are materials that pass visible light.

[0047] Light 45b from the backlight unit 13 passes through the substrate 12, the transistor 14, the pixel electrode 2 1, emitted to the outside of the display device 10A through the liquid crystal layer 22, the common electrode 23, and the substrate 11. In this embodiment, the transistor 14 electrically connected to the liquid crystal element 15 is Therefore, the transistor 14 is provided. The area that is covered by the LCD can also be used as a display area. This increases the aperture ratio of the pixels. The higher the aperture ratio, the higher the light extraction efficiency. It is possible to reduce power consumption and realize a high-definition display device.

[0048] The light 45c from the backlight unit 13 passes through the substrate 12, the capacitance element 16, the pixel electrode 21, The light is emitted to the outside of the display device 10A through the liquid crystal layer 22, the common electrode 23, and the substrate 11. In this embodiment, the capacitance element 16 has a region that transmits visible light. Therefore, the area where the capacitance element 16 is provided can also be used as a display area. This allows the aperture ratio of the pixel to be increased. The higher the aperture ratio, the more efficient the light extraction. Since the efficiency can be increased, the power consumption of the display device can be reduced. This allows for the realization of a thin display device.

[0049] In the display device 10B shown in FIG. 1(B), a backlight unit 13 is disposed on the substrate 11 side. The other configurations are the same as those of the display device 10A. Therefore, the description will be omitted.

[0050] In the display device 10A, the light 45b first passes through the transistor 14, which transmits visible light. Then, the light 45b transmitted through the region is incident on the liquid crystal element 15. On the other hand, in the display device 10B, the light 45b first enters the liquid crystal element 15. Light 45b transmitted through transistor 15 is incident on a region of transistor 14 that transmits visible light. In this way, the light from the backlight unit 13 passes through the transistor 14 and the liquid crystal element It doesn't matter which one of the two 15 is injected first.

[0051] In the display device 10A, the light 45c first enters the capacitance element 16. The transmitted light 45c is incident on the liquid crystal element 15. On the other hand, in the display device 10B, the light 45c is First, the light 45c is incident on the liquid crystal element 15. Then, the light 45c transmitted through the liquid crystal element 15 is incident on the capacitive element 15. The light is incident on the area of ​​the backlight unit 16 that transmits visible light. The light from 3 may be incident on either the capacitance element 16 or the liquid crystal element 15 first.

[0052] Furthermore, the display device of one embodiment of the present invention includes a liquid crystal element, a transistor, a capacitor, and a touch panel. The liquid crystal element has a pixel electrode, a liquid crystal layer, and a common electrode. The touch sensor is electrically connected to the pixel electrode and the capacitance element. The pixel electrode, the common electrode, and the capacitance element are located closer to the display surface than the transistor. Visible light passes through the capacitor element and the liquid crystal element and is reflected by the display device. is ejected to the outside.

[0053] A display device of one embodiment of the present invention is a display device (an input / output device or a touch sensor) equipped with a touch sensor. This can be applied to a touch panel.

[0054] The display device 15A shown in FIG. 2A has a touch sensor unit on the substrate 11 side of the display device 10A. The configuration is such that a set 31 is arranged.

[0055] The display device 15B shown in FIG. 2B has a structure in which a substrate 11 and a common electrode 23 of the display device 10A are connected to each other. The display device is provided with a touch sensor unit 31 and an insulating layer 32. The device 15B has a conductive layer 27 and a conductive layer 28 .

[0056] A conductive layer formed on the insulating layer 26 using the same process and material as the pixel electrode 21. The common electrode 23 is formed in contact with the insulating layer 32 using the same process and material. The conductive layer 28 is formed of a material. The conductive layer 28 is electrically connected to the conductive layer 27 via the connector 29. This allows the one or more FPCs connected to the substrate 12 to be electrically connected. Therefore, both the signal for driving the liquid crystal element 15 and the signal for driving the touch sensor unit 31 It is not necessary to connect an FPC or the like to the substrate 11 side, and the display device can be configured Compared to connecting FPCs to both the substrate 11 side and the substrate 12 side, It is easy to incorporate into electronic devices and reduces the number of parts.

[0057] In the display device 15B, a touch sensor unit 31 can be provided between the pair of substrates. Therefore, the number of substrates can be reduced, and the display device can be made lighter and thinner.

[0058] The display device 15C shown in FIG. 2C has a structure in which, between the substrate 12 and the insulating layer 26 of the display device 10B, The display device is configured to include a touch sensor unit 31 and an insulating layer 32. 15C has a conductive layer 33.

[0059] In contact with the insulating layer 32, the same process as for one or more conductive layers of the transistor 14; and a conductive layer 33 made of the same material. In the display device 15C, the The signal for driving the liquid crystal element 15 and the signal for driving the touch sensor unit are transmitted by one or more FPCs. Therefore, it is easy to incorporate into electronic devices. This also reduces the number of parts.

[0060] In the display device 15C, a touch sensor unit 31 can be provided between the pair of substrates. Therefore, the number of substrates can be reduced, and the display device can be made lighter and thinner.

[0061] [About pixels] Next, a pixel included in the display device of one embodiment of the present invention will be described with reference to FIG.

[0062] FIG. 3(A1) shows a schematic top view of a pixel 900. The pixel 900 shown in FIG. 3(A1) has four In FIG. 3(A1), the pixel 900 has two sub-pixels arranged vertically and one horizontally. In this example, two sub-pixels are arranged. Each sub-pixel is provided with a transmissive liquid crystal element 40 (see FIG. 3(A1)). , (A2) (not shown), a transistor 206, a capacitance element 34, etc. are provided. In FIG. 3(A1), the pixel 900 has two wirings 902 and two wirings 904. In each sub-pixel shown in FIG. 3(A1), a display region 918 (display display area 918R, display area 918G, display area 918B, and display area 918W). is doing.

[0063] The pixel 900 also includes a wiring 902 and a wiring 904. The wiring 902 is, for example, a running The wiring 904 functions as, for example, a signal line. 02 and the wiring 904 have a mutual crossing portion.

[0064] The transistor 206 functions as a selection transistor. The gate electrode is electrically connected to the wiring 902. Alternatively, one of the drain electrodes is electrically connected to the wiring 904, and the other is connected to the liquid crystal element 40, and is electrically connected to the capacitive element 34.

[0065] Here, the wiring 902 and the wiring 904 have a light-shielding property. The transistor 206, the wiring connected to the transistor 206, and each component constituting the capacitor element 34, etc. It is preferable to use a light-transmitting film for the layer. The pixel 900 is divided into a transmission region 900t that transmits visible light and a light-shielding region 900s that blocks visible light. In this example, a transistor is fabricated using a light-transmitting film. By forming the liquid crystal display panel 100 in this manner, the area other than the area where the wiring is provided can be made into a transparent area 900t. The transparent region of the crystal element is overlapped with the transistor, the wiring connected to the transistor, the capacitance element, etc. This allows the aperture ratio of the pixel to be increased.

[0066] The higher the ratio of the area of ​​the transmission region to the area of ​​the pixel, the greater the amount of transmitted light. For example, the ratio of the area of ​​the transparent region to the area of ​​the pixel can be 1% or more and 95% or less. Preferably, the ratio is 10% or more and 90% or less, and more preferably, 20% or more and 80% or less. It is particularly preferable to set the ratio at 40% or more or 50% or more, and it is preferable to set the ratio at 60% or more or 80% or more. It is more preferable that the ratio is less than or equal to the above.

[0067] 3(A2) is a cross-sectional view corresponding to the cut surface of the dashed line AB shown in FIG. 3(B), and 3(B) and 4. In addition, in FIG. 3(B) and FIG. 4, the liquid The cross sections of the crystal element 40, the colored layer 131, the light-shielding layer 132, the drive circuit section 64, etc. are also shown. The driving circuit section 64 is used as a scanning line driving circuit section or a signal line driving circuit section. The driver circuit portion 64 also includes a transistor 201.

[0068] The transistor 206 is preferably a channel-protective transistor. The semiconductor layer 231 has a channel region, and the function of the channel protective layer is provided so as to be in contact with the semiconductor layer 231. An insulating layer 261 having an opening is provided in the insulating layer 261. The opening serves as either the source or the drain of the transistor 206. The conductive layer 222 and the semiconductor layer 231 are electrically connected. An opening is provided, and the source or drain of the transistor 206 is exposed through the opening. The conductive layer 232 having a function as a gate and the semiconductor layer 231 are electrically connected to each other. In the semiconductor layer 231, the connection portion with the conductive layer 222 and the connection portion with the conductive layer 232 are It is preferable that the resistance of the portion is reduced.

[0069] The capacitance element 34 includes a conductive layer 262, an insulating layer 261, and a conductive layer 232. The insulating layer 261 functions as a first electrode of the capacitor 34. The conductive layer 262 functions as a second electrode of the capacitor element 34. That is, the conductive layer 232 functions as a source or a drain of the transistor 206. The insulating layer 261 also functions as a second electrode of the capacitor 34. It functions as a channel protection layer for the transistor 206 and as a dielectric for the capacitor element 34. . The first electrode of the capacitor 34 may be, for example, a lower electrode. The second electrode may be, for example, the top electrode.

[0070] The conductive layer 262 can be formed in the same layer as the semiconductor layer 231. The semiconductor layer is processed by lithography or the like, and then the capacitor element 34 is formed. The conductive layer 262 can be formed by reducing the resistance of the semiconductor layer. The conductive layer 262 has the same composition as the semiconductor layer 231. A resist mask is formed on the thin film to be patterned, and the thin film is processed by etching or the like. The first method is to remove the photomask, and the second method is to deposit a photosensitive thin film, then expose and develop it. and a method of processing the thin film into a desired shape.

[0071] As described above, in the display device of one embodiment of the present invention, by using a channel-protective transistor, When forming the source and drain of a transistor, etc., the channel region of the semiconductor layer is etched. This can prevent damage caused by the transistor. This stabilizes the electrical characteristics of the transistor, resulting in a highly reliable transistor.

[0072] In the display device of one embodiment of the present invention, the first electrode of the capacitor is formed by a semiconductor of the transistor. The dielectric layer of the capacitor element can be formed in the same process as the channel layer of the transistor. The second electrode of the capacitor can be formed in the same process as the transistor protective layer. The source or drain of the transistor can be formed in the same process. The manufacturing process of the display device of one embodiment can be simplified, and the manufacturing cost can be reduced. Cut.

[0073] As shown in FIG. 3(B) and FIG. 4, the light from the backlight unit 13 is reflected by the dashed arrows. The light from the backlight unit 13 is emitted in the direction indicated by the arrow. or is taken out to the outside via the capacitor 34 etc. It is also preferable that the film forming the capacitor 34 has light-transmitting properties. 206, the larger the area of ​​the light-transmitting region of the capacitance element 34, etc., the 13 light can be used efficiently.

[0074] As shown in FIG. 3B and FIG. 4, the light from the backlight unit 13 The liquid may be extracted to the outside through the color layer 131. By extracting the liquid through the color layer 131, the desired liquid can be extracted to the outside. The colored layer 131 can be colored in any desired color. You can choose from cyan (C), magenta (M), yellow (Y), etc.

[0075] In FIG. 3B, the light from the backlight unit 13 first passes through the transistor 206, The light then enters the transistor 206 or the capacitor 34. The transmitted light is incident on the liquid crystal element 40. Then, the light transmitted through the liquid crystal element 40 is reflected by the colored layer It is taken out via 131.

[0076] In FIG. 4, light from the backlight unit 13 first enters the colored layer 131. The light that has passed through the colored layer 131 is incident on the liquid crystal element 40. The transmitted light is extracted to the outside via the transistor 206 or the capacitance element 34 or the like.

[0077] The following materials can be used for the transistors, wirings, capacitors, and the like shown in FIG. 3. These materials are semiconductors that transmit visible light in the configuration examples shown in this embodiment. It can also be applied to the body layer and the conductive layer.

[0078] The semiconductor layer of the transistor can be formed using a light-transmitting semiconductor material. As the light-transmitting semiconductor material, metal oxide or oxide semiconductor (Oxid Oxide semiconductors include at least indium It is preferable that the alloy contains zinc. It is particularly preferable that the alloy contains indium and zinc. In addition to these, aluminum, gallium, yttrium, copper, vanadium, beryllium, Boron, silicon, titanium, iron, nickel, germanium, zirconium, molybdenum, Lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium The composition may contain one or more selected from the group consisting of ammonium, ammonium nitrate ...

[0079] The conductive layers of the transistor and the capacitor are formed using a light-transmitting conductive material. The transparent conductive material is selected from the group consisting of indium, zinc, and tin. It is preferable to include one or more of the following. Specifically, the present invention includes In oxide, In-Sn oxide, and the like. In-Zn oxide (also known as ITO: Indium Tin Oxide), In- W oxide, In-W-Zn oxide, In-Ti oxide, In-Sn-Ti oxide, In- Examples include Sn-Si oxide, Zn oxide, and Ga-Zn oxide.

[0080] In addition, the conductive layers of the transistors and the capacitors may contain impurity elements to reduce the A resistive oxide semiconductor may be used. It can be called an conductor (OC: Oxide Conductor).

[0081] For example, an oxide conductor is formed by forming oxygen vacancies in an oxide semiconductor and adding hydrogen to the oxygen vacancies. By this, a donor level is formed near the conduction band. As a result, the oxide semiconductor becomes electrically conductive and has high conductivity.

[0082] Note that oxide semiconductors have a large energy gap (for example, an energy gap of 2 0.5 eV or more), it is transparent to visible light. The oxide semiconductor has a donor level near the conduction band. Conductors are less affected by absorption due to donor levels and exhibit the same level of absorption as oxide semiconductors for visible light. It has a light transmittance of .

[0083] The oxide conductor may contain one or more metal elements contained in a semiconductor layer of a transistor. It is preferable that the oxide semiconductors constituting the transistors have the same metal element. By using it for two or more of the layers, the manufacturing equipment (for example, film forming equipment, processing equipment, etc.) can be reduced to two or more layers. Since it can be commonly used in the above steps, manufacturing costs can be reduced.

[0084] By using the pixel structure of the display device described in this embodiment, Therefore, the light emitted from the LED can be used efficiently. An excellent display device can be provided.

[0085] <2. Display Device Configuration Example 2> Next, a display device according to one embodiment of the present invention will be described with reference to FIGS. 5 is a perspective view of the display device 100. FIG. 6 is a cross-sectional view of the display device 100. In FIG. 5, the substrate 61 is shown by a dashed line.

[0086] The display device 100 includes a display unit 62 and a drive circuit unit 64. PC72 and IC73 are implemented.

[0087] The display unit 62 has a plurality of pixels 900 and has the function of displaying an image.

[0088] The pixel 900 has a plurality of sub-pixels. For example, a sub-pixel that exhibits red, a sub-pixel that exhibits green, and so on. A single pixel is formed by a blue sub-pixel and a blue sub-pixel. It is possible to display full color. The colors displayed by the sub-pixels are red, green, and blue. The pixel may include sub-pixels that exhibit colors such as white, yellow, magenta, or cyan. In this specification and the like, a sub-pixel may be simply referred to as a pixel.

[0089] The display device 100 has one or both of a scanning line driving circuit and a signal line driving circuit. Alternatively, it is possible to use a display device that does not have both a scanning line driver circuit and a signal line driver circuit. When the display device 100 has a sensor such as a touch sensor, the display device 100 In this embodiment, the driving circuit section 64 includes a scanning line driver circuit. The scanning line driving circuit outputs scanning signals to the scanning lines of the display unit 62. It has the function of outputting.

[0090] In the display device 100, the IC 73 is mounted on the substrate 51 by a mounting method such as the COG method. The IC 73 is, for example, a signal line driving circuit, a scanning line driving circuit, and a sensor driving circuit. It has one or more of the following.

[0091] The display device 100 is electrically connected to an FPC 72. Signals and power are supplied from the outside to the FPC 73 and the drive circuit section 64. A signal can be output from IC73 to the outside via

[0092] An IC may be mounted on the FPC 72. For example, the FPC 72 may include a signal line drive circuit. An IC having one or more of the following circuits, a scanning line driver circuit, and a sensor driver circuit is mounted. It may be done.

[0093] Signals and power are supplied to the display unit 62 and the drive circuit unit 64 through wiring 65. The signal and power are input to the wiring 65 from the IC 73 or from the outside via the FPC 72. Be encouraged.

[0094] 6 is a cross-sectional view including a pixel 900 and a driving circuit unit 64. As shown in FIG. The display device 100 includes a substrate 51, a transistor 201, a transistor 206, a liquid crystal element 40, Alignment film 133a, alignment film 133b, connection portion 204, adhesive layer 141, colored layer 131, light-shielding layer 132, an overcoat 121, and a substrate 61.

[0095] The liquid crystal element 40 includes a pixel electrode 111, a common electrode 112, and a liquid crystal layer 113. The orientation of the liquid crystal layer 113 is controlled by the electric field generated between the electrode 111 and the common electrode 112. The liquid crystal layer 113 is located between an alignment film 133a and an alignment film 133b.

[0096] In FIG. 6, the pixel electrode 111 is electrically connected to the conductive layer 232. The conductive layer 232 is connected to the other of the source electrode and the drain electrode of the transistor 206, The capacitor 34 has a function as a second electrode and is formed using a material that transmits visible light. The conductive layer 262 functioning as the first electrode of the capacitor 34 also transmits visible light. As a result, the area where the capacitor element 34 is provided is the display area 91. Therefore, the aperture ratio of the pixel 900 can be increased. This allows the power consumption of the display device 100 to be reduced.

[0097] 6, an alignment film is provided so as to be in contact with the liquid crystal layer 113. The alignment film It has a function of controlling the alignment of the liquid crystal layer 113. In FIG. An alignment film 133a is provided, and an alignment film 133b is provided so as to be in contact with the common electrode 112. The alignment film 133a and / or the alignment film 133b may not be provided.

[0098] There are two types of liquid crystal materials: positive-type, in which the anisotropy of the dielectric constant (Δε) is positive, and negative-type, in which the anisotropy of the dielectric constant (Δε) is negative. In one embodiment of the present invention, either material can be used, and the applied model The optimum liquid crystal material can be used depending on the mode and design.

[0099] In one embodiment of the present invention, it is preferable to use a negative liquid crystal material. The influence of the flexoelectric effect caused by molecular polarization can be suppressed, and the transmittance due to polarity can be reduced. Therefore, the flicker is hardly visible to the user of the display device. The flexoelectric effect is mainly caused by molecular shape and can be suppressed by orientation distortion. This is a phenomenon in which polarization occurs. Negative liquid crystal materials have orientation distortions such as spreading deformation and bending deformation. It's difficult.

[0100] It should be noted that liquid crystal elements to which various modes are applied can be used as the liquid crystal element 40. For example, FFS (Fringe Field Switching) mode, VA (Ver tical Alignment mode, TN (Twisted Nematic) mode Mode, IPS (In-Plane-Switching) mode, ASM (Axiall y Symmetric aligned Micro-cell) mode, OCB(O (Ptically Compensated Birefringence) mode, F LC (Ferroelectric Liquid Crystal) mode, AFLC (AntiFerroelectric Liquid Crystal) mode, EC B(Electrically Controlled Birefringence) Use of LCD elements that use mode, VA-IPS mode, guest host mode, etc. can be done.

[0101] The display device 100 may be a normally black type liquid crystal display device, for example, a vertical alignment (VA) A transmissive liquid crystal display device employing a vertical alignment mode may be used. VA (Multi-Domain Vertical Alignment) mode, P VA(Patterned Vertical Alignment) mode, ASV( Advanced Super View mode, etc. can be used.

[0102] The liquid crystal element is an element that controls the transmission or non-transmission of light by the optical modulation action of the liquid crystal. The optical modulation effect of liquid crystals is due to the electric field (horizontal electric field, vertical electric field or For example, the optical properties of the liquid crystal can be controlled by a horizontal electric field. When controlling the dynamic modulation effect, the control method can be called a lateral electric field method. The liquid crystals used include thermotropic liquid crystals, low molecular weight liquid crystals, polymer liquid crystals, and polymer dispersion liquids. Crystal (PDLC: Polymer Dispersed Liquid Crystal) These liquid crystal materials can be used under certain conditions. Cholesteric phase, smectic phase, cubic phase, chiral nematic phase, etc. Indicates directions, etc.

[0103] When the in-plane switching system is adopted, a liquid crystal that exhibits a blue phase without using an alignment film may be used. The blue phase is one of the liquid crystal phases, and when the temperature of cholesteric liquid crystal is increased, the cholesteric The blue phase appears just before the transition from the crystalline phase to the isotropic phase. In order to improve the temperature range, a liquid crystal composition containing 5% by weight or more of a chiral agent is used. The liquid crystal composition containing the liquid crystal exhibiting a blue phase and the chiral agent is used for the liquid crystal layer 113. The response speed is short and the liquid crystal exhibits optical isotropy. The crystal composition does not require alignment treatment and has little viewing angle dependency. Since the rubbing process is unnecessary, electrostatic damage caused by the rubbing process is eliminated. This can prevent defects or damage to the liquid crystal display device during the manufacturing process. Cut.

[0104] Since the display device 100 is a transmissive liquid crystal display device, the pixel electrode 111 and the common electrode 1 12, one or both of which is made of a conductive material that transmits visible light. One or both of the conductive layers 232 and 262 may be made of a conductive material that transmits visible light. There are.

[0105] Examples of conductive materials that transmit visible light include indium (In), zinc (Zn), and tin. It is preferable to use a material containing one or more selected from the group consisting of indium oxide (Sn). Contains indium, indium tin oxide (ITO), indium zinc oxide, and tungsten oxide Indium oxide, indium zinc oxide with tungsten oxide, indium zinc oxide with titanium oxide Indium oxide, indium tin oxide with titanium oxide, indium with silicon oxide Examples include tin oxide (ITSO), zinc oxide, and zinc oxide containing gallium. A graphene-containing film can also be used. The graphene-containing film can be, for example, a film containing graphene oxide. The film can be formed by reducing a film containing the metal.

[0106] One or more of the conductive layer 232, the conductive layer 262, the pixel electrode 111, and the common electrode 112 It is preferable to use at least one oxide conductor. It is preferable that the semiconductor layer 231 of No. 6 contains one or more metal elements. The conductive layer 262 preferably contains indium and is an In-M-Zn oxide (where M is Al, T It is more preferred that the film is a ZnO film, such as Ti, Ga, Y, Zr, La, Ce, Nd, Sn, or Hf. The conductive layer 232 is preferably an In-Zn oxide film. By using an In-Zn oxide film as the conductive layer 232, the display device 1 This can prevent the resistance from increasing during the manufacturing process of 00.

[0107] One or more of the conductive layer 232, the conductive layer 262, the pixel electrode 111, and the common electrode 112 A plurality of the first and second insulating layers may be formed using an oxide semiconductor. By using this for two or more layers constituting the display device, Manufacturing costs can be reduced because the same equipment (e.g., processing equipment) can be used in two or more processes. It is possible.

[0108] The oxide semiconductor has at least one of oxygen vacancies and impurity concentrations such as hydrogen and water in the film. On the other hand, oxide semiconductors are semiconductor materials whose resistance can be controlled by Treatment that increases oxygen deficiency and / or impurity concentration in the body, or oxygen deficiency By performing treatment to reduce at least one of the impurity concentration and the The resistivity of the oxide semiconductor can be controlled by adjusting the oxygen vacancy and the impurity concentration. The oxide semiconductor is made to have a low resistance by performing a treatment to increase at least one of the above. A conductor can be formed.

[0109] In this way, an oxide conductor formed using an oxide semiconductor has a high carrier density. low-resistance oxide semiconductor, conductive oxide semiconductor, or highly conductive oxide semiconductor It can also be called the body.

[0110] In addition, by forming the oxide semiconductor and the oxide conductor from the same metal element, the manufacturing cost can be reduced. For example, by using a metal oxide target with the same metal composition, In addition, the manufacturing cost can be reduced by using a metal oxide target of the same metal composition. By using the above, the etching gas or etching solution when processing the oxide semiconductor can be However, the oxide semiconductor and the oxide conductor may be made of the same metal. Even if the metal element is present, the composition may be different. The metal elements in the powder may be released, resulting in a different metal composition.

[0111] The transistor 206 includes a gate electrode 221, an insulating layer 211, a semiconductor layer 231, and an insulating layer 26. 1, conductive layer 222, and conductive layer 232. The semiconductor layer 231 contains indium. In-M-Zn oxide (wherein M is Al, Ti, Ga, Y, Zr, La, Ce) is preferred. , Nd, Sn, or Hf) film is more preferred.

[0112] The gate electrode 221 has a region overlapping with the semiconductor layer 231 via the insulating layer 211. Specifically, the gate electrode 221 overlaps the channel region of the semiconductor layer 231 via the insulating layer 211. It has the following areas.

[0113] In addition, a semiconductor layer 231 is provided so as to be in contact with the insulating layer 211. An insulating layer 261 is provided so as to contact the insulating layer 211 and the conductive layer 222. The insulating layer 261 is electrically connected to the semiconductor layer 231 through an opening provided in the insulating layer 261. The conductive layer 232 is electrically connected to the semiconductor layer 231 through an opening provided in the insulating layer 261. is connected.

[0114] The insulating layer 211 functions as a gate insulating layer of the transistor 206. The insulating layer 261 is a channel protection layer for the transistor 206. The conductive layer 222 functions as a source electrode or a drain electrode of the transistor 206. The conductive layer 232 serves as one of the source electrodes of the transistor 206. Alternatively, it functions as the other of the drain electrodes.

[0115] The gate electrode 221 can also be a part of the scanning line. The conductive layer 204 may have a portion overlapping with the channel region of the conductive layer 206. The conductive layer 222 can be a part of the signal line. It is preferable that the electrical resistance of the electrical layer 222 is sufficiently low. The conductive layer 222 is preferably formed using a metal, an alloy, or the like. For the conductive layer 222, a material that has a function of blocking visible light may be used.

[0116] As described above, the conductive layer 232 is made of a material that transmits visible light. That is, in one embodiment of the present invention, the transistor 206 is preferably The conductive layer 232 may be formed using a material different from that of the conductive layer 231 .

[0117] Specifically, conductive materials that transmit visible light and can be used for the conductive layer 232 and the like include copper and and aluminum, which may have a higher resistivity than conductive materials that block visible light. Therefore, in order to prevent signal delay, bus lines such as scanning lines and signal lines are made of visible light having low resistivity. It is preferable to form the light-shielding conductive material, for example, a metal material such as copper. The gate electrode 221 and the conductive layer 222 are preferably formed using a metal material such as copper. However, depending on the pixel size, width and thickness of the bus line, etc. The lines can be made of a conductive material that transmits visible light.

[0118] Furthermore, by using a conductive layer that blocks visible light for the gate electrode 221, the light from the backlight is transmitted to the semiconductor. This can prevent the light from irradiating the conductive layer 231. This can suppress the noise and improve the reliability of the transistor.

[0119] A light-shielding layer 132 is provided on the substrate 61 side of the semiconductor layer 231, and a light-shielding layer 132 is provided on the substrate 51 side of the semiconductor layer 231. By providing a gate electrode 221 that blocks visible light, external light and backlight This can prevent the semiconductor layer 231 from being irradiated with light.

[0120] In one embodiment of the present invention, the conductive layer that blocks visible light overlaps a portion of the semiconductor layer 231 and For example, the conductive layer that blocks visible light may not overlap with other parts of the conductive layer 231. Both of them may overlap with the channel region of the semiconductor layer 231.

[0121] The transistor 206 is covered with an insulating layer 212, an insulating layer 214, and an insulating layer 215. The insulating layer 212, the insulating layer 214, and the insulating layer 215 are formed on the insulating layer 212 of the transistor 206. The insulating layer 215 can also be regarded as a component. The insulating layer 215 functions as a planarization layer.

[0122] The insulating layer 212 may contain more oxygen than the oxygen required for the stoichiometric composition. It is also preferable to form the insulating layer 214 and the insulating layer 215 from oxygen that satisfies the stoichiometric composition. The oxygen contained in the insulating layer 212 or the like can be removed by heat treatment or the like. A part of the electrons passes through the insulating layer 261 and is supplied to the channel region of the semiconductor layer 231. When the channel region of the semiconductor layer 231 is an oxide semiconductor, the oxygen in the channel region As a result, the resistance of the channel region of the semiconductor layer 231 can be increased. This makes it possible to suppress fluctuations in the electrical characteristics of the transistor and improve reliability.

[0123] For example, when an oxide conductor is used as the conductive layer 262, the insulating layer 212 and the like contain Oxygen may diffuse into the conductive layer 262, causing the conductive layer 262 to have a high resistance. The conductive layer 232 is made of a material that is difficult for oxygen to permeate. The oxygen contained in the conductive layer 262 is difficult to be supplied to the conductive layer 262. Even when a conductive material is used, the resistance of the conductive layer 262 can be prevented from increasing.

[0124] In the display device 100, a colored layer 131 and a light-shielding layer 13 are provided on the substrate 61 side of the liquid crystal layer 113. The colored layer 131 overlaps at least the display area 918 of the pixel 900. A light-shielding layer 132 is provided in the area other than the display area 918 (non-display area). The light-shielding layer 132 overlaps at least a portion of the transistor 206.

[0125] An overcoat 121 is provided between the colored layer 131 and the light-shielding layer 132 and the liquid crystal layer 113. The overcoat 121 is preferably provided with a colored layer 131, a light-shielding layer 132, etc. This can prevent impurities contained in the film from diffusing into the liquid crystal layer 113.

[0126] The substrate 51 and the substrate 61 are bonded together by an adhesive layer 141. The liquid crystal layer 113 is sealed in the area surrounded by the adhesive layer 141 and the insulating layer 61 .

[0127] When the display device 100 is made to function as a transmissive liquid crystal display device, the polarizing plate is In FIG. 6, the polarizing plate 130 on the substrate 61 side is shown. The light from the backlight arranged outside the polarizing plate on the 51 side passes through the polarizing plate. At this time, the voltage applied between the pixel electrode 111 and the common electrode 112 The orientation of the layer 113 can be controlled to control the optical modulation of light. The intensity of the light emitted through the colored layer 131 can be controlled. Therefore, light outside of a specific wavelength range is absorbed, and the emitted light is, for example, red, blue, or The light will be green or blue.

[0128] In addition to the polarizing plate, for example, a circular polarizing plate can be used. For example, a laminate of a linear polarizer and a quarter-wave retardation plate can be used. This reduces the viewing angle dependency of the display device.

[0129] Moreover, the liquid crystal element 40 is preferably driven using a guest-host liquid crystal mode. When using the guest-host liquid crystal mode, no polarizer is required. This reduces the absorption of light, improving the light extraction efficiency and making the display brighter. .

[0130] The driving circuit unit 64 includes a transistor 201 .

[0131] The transistor 201 includes a gate electrode 221, an insulating layer 211, a semiconductor layer 231, and an insulating layer 26. 1, conductive layer 224, and conductive layer 225. That is, one functions as a source electrode and the other functions as a drain electrode. An opening is provided in the insulating layer 261, and the conductive layer 224 and the semiconductor layer 23 are connected to each other through the opening. 1 is electrically connected. An opening is provided in the insulating layer 261. The conductive layer 225 and the semiconductor layer 231 are electrically connected via the In 231, the connection part with the conductive layer 224 and the connection part with the conductive layer 225 are made to have low resistance. It is preferable to do so.

[0132] The transistors provided in the driver circuit section 64 do not need to have a function of transmitting visible light. That is, the conductive layer 224 and the conductive layer 225 can be formed using a metal material or the like. Specifically, it can be formed using the same material as the conductive layer 222. The conductive layer 224, the conductive layer 225, and the conductive layer 222 can be formed in the same process. .

[0133] In the connection portion 204, the wiring 65 and the conductive layer 251 are connected to each other, and the conductive layer 251 and the connection body 24 2 are connected to each other. That is, at the connection portion 204, the conductive layer 225 is connected to the conductive layer 251. The FPC 72 is electrically connected via the connector 242. Thus, signals and power can be supplied from the FPC 72 to the wiring 65.

[0134] The wiring 65 is connected to the conductive layer 224, the conductive layer 225, and the The conductive layer 222 of the stator 206 can be formed using the same material and in the same process. The electrode layer 251 is formed of the same material and in the same process as the pixel electrode 111 of the liquid crystal element 40. In this way, the conductive layer that forms the connection portion 204 can be formed on the pixel 900 and the driving circuit If the conductive layer is made of the same material and in the same process as the conductive layer used in the portion 64, an increase in the number of processes can be prevented. This is preferable.

[0135] The transistor 201 and the transistor 206 may have the same structure or different structures. That is, the transistors included in the driver circuit portion 64 and the transistors included in the pixel 900 may be The transistors may have the same structure or different structures. The transistor included in 4 does not have to be a channel protection type transistor. For example, Alternatively, the driving circuit section 64 may be a transistor of a plurality of structures. The pixel 900 may have a transistor of a plurality of structures. For example, the driving circuit section 64 may be configured with a channel protection type transistor and a channel etch type transistor. For example, the pixel 900 may include a channel protection transistor. The transistor may have a channel-etched type.

[0136] In addition, the semiconductor layer 231 of the transistor 201 and the semiconductor layer 232 of the transistor 206 For example, the semiconductor layer 231 of the transistor 201 may be formed of a different material. The conductor layer 231 is made of amorphous silicon or low-temperature polysilicon. An oxide semiconductor may be used as the semiconductor layer 231 of the transistor 206. By using amorphous silicon or low-temperature polysilicon for the semiconductor layer of the As a result, the on-state current of the transistor can be increased. Furthermore, it is possible to reduce the area occupied by the circuit portion. By applying transistors with large on-state current, it is possible to increase the size of display devices or improve their resolution. Even if the number of wires increases, it is possible to reduce the signal delay in each wire. By applying this configuration, it is possible to suppress display unevenness. High-performance transistors can be realized.

[0137] FIG. 7 shows a modified example of the display device 100. The display device 100 shown in FIG. The fact that the gate electrode 223 is provided in the transistor 206 and the transistor 201 is the same as that in the configuration shown in FIG. This is different from the display device 100.

[0138] The gate electrode 223 is provided so as to be in contact with the insulating layer 214. The gate electrode 223 is provided to have a region overlapping with the semiconductor layer 231. For example, a metal material such as copper can be used as the gate electrode 2. The gate electrode 223 can be made of the same material as the gate electrode 221. For example, the gate electrode 221 and the gate electrode 223 may be formed of different materials. One of the gate electrodes may be made of a material having a light-shielding property, such as a metal material. One of the electrode 221 and the gate electrode 223 may be formed using an oxide conductor.

[0139] The gate electrode 221 and the gate electrode 223 can be electrically connected. A transistor with two gate electrodes electrically connected to each other is It is possible to increase the field effect mobility and the on-current compared to As a result, a circuit capable of high-speed operation can be fabricated. By using a transistor with a large on-current, the display Even if the number of wires increases due to the larger size or higher resolution of the device, the signal delay in each wire It is possible to reduce the amount of light emitted from the display, and to suppress uneven display. By applying this configuration, a highly reliable transistor can be realized.

[0140] Note that some of the transistors included in the display device 100 have gate electrodes 22 3, and the other transistors may not have the gate electrode 223. For example, the transistor 201 has a gate electrode 223, and the transistor 20 The transistor 206 may not have the gate electrode 223. The transistor 201 has a gate electrode 223, and the transistor 202 does not have a gate electrode 223. Alternatively, some or all of the transistors included in the display device 100 may be replaced with other transistors. Alternatively, the gate electrode 221 may not be provided.

[0141] Next, materials that can be used for each component of the display device of one embodiment of the present invention will be described in detail. The explanation will be given below. Note that the explanation of components that have already been explained may be omitted. In addition, the following materials are also used in the display devices and touch panels, as well as their components, which will be described later. can be used appropriately.

[0142] <Substrates 51 and 61> There is no particular limitation on the material of the substrate included in the display device of one embodiment of the present invention, and various substrates can be used. For example, a glass substrate, a quartz substrate, a sapphire substrate, a semiconductor substrate, a ceramic substrate, A black substrate, a metal substrate, a plastic substrate, or the like can be used.

[0143] By using a thin substrate, the display device can be made lighter and thinner. Furthermore, by using a substrate thick enough to be flexible, a flexible display device can be realized. can.

[0144] In the display device of one embodiment of the present invention, a transistor or the like is formed over a formation substrate, and then a transistor or the like is formed on another substrate. By using a fabrication substrate, the characteristics of Formation of good transistors, formation of low-power-consumption transistors, and durable display devices Manufacturing, imparting heat resistance to the display device, reducing the weight of the display device, or making the display device thinner. The substrate onto which the transistor is transferred is provided with a material capable of forming a transistor. Not limited to substrates, but also paper substrates, cellophane substrates, stone substrates, wood substrates, cloth substrates (natural fibers (silk) , cotton, linen), synthetic fibers (nylon, polyurethane, polyester) or recycled fibers (a acetate, cupro, rayon, recycled polyester, etc.), leather substrate, or rubber A substrate or the like can be used.

[0145] Semiconductor layer The semiconductor material used for the semiconductor layer is not particularly limited, and examples thereof include oxide semiconductors, silicon, There are no particular restrictions on the crystallinity of the semiconductor material used in the semiconductor layer. It is not necessary to use amorphous semiconductors, crystalline semiconductors (microcrystalline semiconductors, polycrystalline semiconductors, single crystal semiconductors) The material may be either a conductor or a semiconductor having a crystalline region in part. The use of a semiconductor is preferable because it can prevent the deterioration of transistor characteristics.

[0146] For example, a Group 14 element, a compound semiconductor, or an oxide semiconductor can be used for the semiconductor layer. Typically, a semiconductor containing silicon, a semiconductor containing gallium arsenide, or indium An oxide semiconductor containing the above can be used for the semiconductor layer.

[0147] An oxide semiconductor is preferably used as a semiconductor in which a channel of a transistor is formed. In particular, it is preferable to use an oxide semiconductor having a larger band gap than silicon. If a semiconductor material with a wider band gap and lower carrier density than silicon is used, This is preferable because it can reduce the current in the off state of the transistor.

[0148] For the oxide semiconductor, the above description and Embodiment 4 can be referred to.

[0149] By using an oxide semiconductor, fluctuations in electrical characteristics can be suppressed, resulting in highly reliable transistors. It can be achieved.

[0150] In addition, due to its low off-state current, the charge stored in the capacitor can be released over a long period of time via the transistor. By applying such a transistor to the pixel, It is also possible to stop the driving circuit while maintaining the gradation of the image. A display device with reduced power consumption can be realized.

[0151] The transistors 201 and 206 are highly purified to suppress the formation of oxygen vacancies. It is preferable that the transistor has an oxide semiconductor containing the SiO 2 . Therefore, when an electric signal such as an image signal is held, the current value (off-state current value) can be reduced. The write interval can be set to a longer value when the power is on. This reduces the frequency of refresh operations, which has the effect of reducing power consumption. .

[0152] Furthermore, the transistor 201 and the transistor 206 have a relatively high field-effect mobility. This allows for high-speed driving. By using this device, the transistors of the display section and the transistors of the drive circuit section can be mounted on the same substrate. That is, a drive circuit can be formed separately using a silicon wafer or the like. Since there is no need to use a semiconductor device that has been modified, the number of components in the display device can be reduced. In addition, the display section also uses transistors that can be driven at high speed, enabling high-quality images. An image can be provided.

[0153] <Insulating layer> Insulating material that can be used for various insulating layers, overcoats, spacers, etc. in display devices As the insulating material, an organic insulating material or an inorganic insulating material can be used. For example, acrylic resin, epoxy resin, polyimide resin, polyamide resin, polyimide amide resin, siloxane resin, benzocyclobutene resin, and phenolic resin. Examples of inorganic insulating layers include a silicon oxide film, a silicon oxynitride film, and a silicon nitride oxide film. Silicon film, silicon nitride film, aluminum oxide film, hafnium oxide film, yttrium oxide film , zirconium oxide film, gallium oxide film, tantalum oxide film, magnesium oxide film, la oxide film Examples of the thin film include titanium oxide, cerium oxide, and neodymium oxide.

[0154] <Conductive layer> In addition to the gate, source, and drain of a transistor, various wirings and electrodes of a display device Conductive layers such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, etc. Metals such as tungsten, molybdenum, silver, tantalum, or tungsten, or those containing these as the main component The alloy can be used as a single layer or a laminated structure. Two-layer structure in which a titanium film is laminated on a tungsten film, two-layer structure in which a titanium film is laminated on a tungsten film, Two-layer structure with copper film laminated on molybdenum film, and alloy film containing molybdenum and tungsten Two-layer structure with copper film laminated, two-layer structure with copper film laminated on copper-magnesium-aluminum alloy film A layer structure, a titanium film or a titanium nitride film, and an aluminum film overlaid on the titanium film or the titanium nitride film. An aluminum film or a copper film is laminated, and a titanium film or a titanium nitride film is further formed thereon. A three-layer structure consisting of a molybdenum film or molybdenum nitride film and a molybdenum film or molybdenum nitride film. An aluminum or copper film is layered on top of the molybdenum film, and then a molybdenum or For example, when the conductive layer has a three-layer structure, In this case, the first and third layers are made of titanium, titanium nitride, molybdenum, tungsten, molybdenum, alloys containing tungsten and molybdenum, alloys containing zirconium and molybdenum, or molybdenum nitride The first layer is made of copper, aluminum, gold or silver, or copper and manganese. It is preferable to form a film made of a low resistance material such as an alloy of ITO or titanium oxide. Indium oxide containing tungsten, indium zinc oxide containing tungsten oxide, oxide Indium oxide containing titanium, indium tin oxide containing titanium oxide, indium zinc A light-transmitting conductive material such as oxide or ITSO may also be used.

[0155] Note that an oxide conductor may be formed by controlling the resistivity of an oxide semiconductor.

[0156] ≪Adhesive layer 141≫ The adhesive layer 141 is made of a hard material such as a thermosetting resin, a photocurable resin, or a two-liquid mixed type hardening resin. For example, acrylic resin, urethane resin, epoxy resin, Alternatively, a siloxane resin or the like can be used.

[0157] <Connector 242> The connector 242 may be, for example, an anisotropic conductive film (ACF). Conductive Film), or Anisotropic Conductive Paste (ACP) For example, a tropic conductive paste can be used.

[0158] ≪Colored layer 131≫ The colored layer 131 is a colored layer that transmits light in a specific wavelength band. Materials that can be used include metal materials, resin materials, and resin materials containing pigments or dyes. etc.

[0159] ≪Light-shielding layer 132≫ The light-shielding layer 132 is provided, for example, between adjacent colored layers 131 of different colors. Black matrix formed using a metal material or a resin material containing a pigment or dye. The light-shielding layer 132 can be formed by the driving circuit section 64. It is preferable to provide the same in an area other than the pixel 900, for example, because it is possible to suppress light leakage due to guided light, etc. stomach.

[0160] <3. Example of a method for manufacturing a display device> An example of a method for manufacturing the display device 100 having the configuration shown in FIG. 6 will be described with reference to FIGS. 8(A), 8(B), and 8(C). ) and Figures 9(A) and (B). By changing the configuration of the transistors and the liquid crystal elements, other display devices of this embodiment can also be used. It can be made.

[0161] The thin films (insulating films, semiconductor films, conductive films, etc.) that make up the display device are each formed by sputtering. method, chemical vapor deposition (CVD) method , vacuum evaporation, pulsed laser deposition (PLD) ion) method, Atomic Layer Deposition (ALD) The CVD method can be, for example, plasma-enhanced chemical vapor deposition (PE Examples of thermal CVD include metal organic chemical vapor deposition (MOCVD) and thermal CVD. deposition (MOCVD: Metal Organic CVD) method.

[0162] The thin films (insulating films, semiconductor films, conductive films, etc.) that make up the display device are formed by spin coating, Dip, spray application, inkjet printing, dispensing, screen printing, offset Printing, doctor knife, slit coating, roll coating, curtain coating, knife coating The film can be formed by a method such as a coating method.

[0163] The thin film constituting the display device can be processed using a lithography method or the like. Alternatively, an island-shaped thin film may be formed by a film formation method using a shielding mask. The thin film may be processed by a lint method, a sandblasting method, a lift-off method, or the like.

[0164] When processing using photolithography, the light used for exposure is, for example, i-line (wavelength ray (wavelength 365nm), g-ray (wavelength 436nm), h-ray (wavelength 405nm), and a mixture of these. Other examples include ultraviolet light, KrF laser light, and ArF laser light. The exposure may also be performed by immersion exposure. Extreme ultraviolet (EUV) and X In place of light used for exposure, an electron beam can also be used. Extreme ultraviolet light, X-rays, or electron beams are preferred because they enable extremely fine processing. When exposure is performed by scanning a beam such as an electron beam, a photo No sc is required.

[0165] For etching thin films, there are dry etching, wet etching, and sandblasting methods. etc. can be used.

[0166] When manufacturing the display device 100, first, a conductive layer is formed on the substrate 51, and the conductive layer is then lithographed. By processing using a lithography method or the like, a wiring 902 and a gate electrode 221 are formed. As described above, the wiring 902 functions as a scanning line. The wiring 902 and the gate electrode 221 have low resistivity. It is preferable to form the insulating layer using a conductive material that blocks visible light, for example, a metal material such as copper.

[0167] Next, the insulating layer 211 is formed. As described above, the insulating layer 211 is formed on the insulating layer 211 provided on the display device 100. The gate insulating layer of the transistor is formed on the insulating layer.

[0168] Thereafter, a semiconductor layer is formed and processed by lithography or the like. Then, a semiconductor layer 231 and a semiconductor layer 262a are formed (FIG. 8(A)). , which has a region that functions as a channel region of a transistor provided in the display device 100. The semiconductor layer 231 and the semiconductor layer 262a are preferably made of an oxide semiconductor. For example, it is preferable to contain indium, and In-M-Zn oxide (wherein M is Al, Ti, More preferably, the film is a Ga, Y, Zr, La, Ce, Nd, Sn or Hf film.

[0169] Next, the insulating layer 261 is formed (FIG. 8(B)). As described above, the insulating layer 261 is The channel protection layer of the transistor provided in the display device 100 and It functions as a dielectric layer of the capacitance element.

[0170] The insulating layer 261 can be, for example, a silicon oxynitride film. For example, the film can be formed by a CVD method, particularly a PECVD method. When forming a film by CVD, for example, silane gas is used as the film forming gas, and Nitrogen oxide gas such as nitrous oxide is used. In this case, hydrogen or the like is mixed during the formation of the insulating layer 261. The conductive layer 262a is supplied with the electric current, and the resistance of the semiconductor layer 262a can be reduced. , a conductive layer 262 having a function as a first electrode of a capacitor provided in the display device 100 can be formed.

[0171] The insulating layer 261 formed by the above method contains ammonia. Even if a heat treatment or the like is performed after the formation of the conductive layer 262 and hydrogen or the like supplied to the conductive layer 262 diffuses outward, The ammonia contained in the insulating layer 261 is supplied to the conductive layer 262, 62 can be prevented from increasing in resistivity.

[0172] In addition, hydrogen or the like is supplied to the semiconductor layer 231 during the formation of the insulating layer 261, and the semiconductor layer 231 becomes active. However, in the subsequent process, the resistance of the channel region where the semiconductor layer Since the channel region of the insulating layer 231 can be made highly resistant, Therefore, there is no problem even if the resistance is reduced.

[0173] Next, an opening is formed in the insulating layer 261, reaching the semiconductor layer 231, and then the semiconductor layer 232a The semiconductor layer 232a has a region overlapping with the conductive layer 262. The conductor layer 232 a is electrically connected to the semiconductor layer 231 through an opening provided in the insulating layer 261 . is connected to.

[0174] For example, In-Zn oxide is preferably used as the semiconductor layer 232a. The substrate temperature is set to a temperature where it is not intentionally heated by the sputtering method, and argon (Ar It is preferable to form the In-Zn oxide film in a 100% ammonium hydroxide atmosphere. By using In-Zn oxide as the layer 232a, the resistance of the semiconductor layer 232a can be reduced in a later step. The conductive layer 232 can be formed, and the formed conductive layer 232 can be further The semiconductor layer 232a is made of In—Zn An oxide semiconductor other than oxide may be used. In this case, the semiconductor layer 232a is It is preferable that the semiconductor layer 232a contains one or more metal elements contained in the semiconductor layer 232a. If the metal element in 231 is contained in one or more types, the manufacturing equipment (e.g., film forming equipment, processing equipment) Since it is possible to share the same equipment for two or more processes, manufacturing costs can be reduced. This can be done.

[0175] Next, an opening is formed in the insulating layer 261 to reach the semiconductor layer 231, and then the conductive layer 222 and the conductive layer 231 are formed. Then, the conductive layer 224, the conductive layer 225, and the wiring 65 are formed (FIG. 8(C)). 22, the conductive layer 224, and the conductive layer 225 are connected to each other through openings provided in the insulating layer 261. , and is electrically connected to the semiconductor layer 231.

[0176] As described above, the conductive layer 222 is a source or drain electrode of the transistor 206. The conductive layer 224 functions as a source electrode of the transistor 201. The conductive layer 225 functions as one of the gate and drain electrodes of the transistor 2. The conductive layer 222 also functions as the other of the source and drain electrodes of the conductive layer 222. The conductive layer 222, the conductive layer 224, the conductive layer 225 and the conductive layer 226 can be part of the signal line. The wiring 65 is made of a conductive material that has low resistivity and blocks visible light, such as a metal material such as copper. It is preferable to form

[0177] Since the insulating layer 261 functions as a channel protection layer, the conductive layer 222 and the semiconductor Upon formation of layer 232a, conductive layer 224, and conductive layer 225, the channel of semiconductor layer 231 This can prevent damage to the region caused by etching. The electric characteristics of the transistors included in the display device 100 can be stabilized, and the transistors can be made highly reliable. It is possible to realize

[0178] After the opening is formed in the insulating layer 261, an inert gas such as argon is introduced into the semiconductor layer 231. By supplying the source voltage of transistor 206 and / or transistor 201 The contact portion with the electrode and the contact portion with the drain electrode may be made n-type. For example, sputtering, ion implantation, ion doping, plasma immersion, This can be achieved by ion implantation, plasma treatment, or the like. and / or increasing the on-state current of the transistor 201 to speed up the operation of the display device 100. It is possible.

[0179] Next, an insulating layer 212 is formed. The insulating layer 212 may be formed of, for example, silicon oxynitride. The insulating layer 212 can be formed by, for example, a CVD method, particularly a PECVD method. When a film containing silicon oxynitride is formed by a CVD method, for example, Silane gas is used as the film forming gas, and nitrogen oxide gas such as nitrous oxide gas is also used. In this case, hydrogen or the like is supplied to the semiconductor layer 232a during the formation of the insulating layer 212, and the semiconductor layer 23 2a can be made low resistance. A conductive layer having a function as a drain electrode and a function as a second electrode of the capacitor 34. Layer 232 can be formed.

[0180] In addition, the insulating layer 212 may contain more oxygen than the oxygen required for the stoichiometric composition. For example, when the insulating layer 212 is formed by the CVD method, oxygen or Alternatively, a mixture of oxygen and nitrogen oxide gases such as nitrous oxide and nitrogen dioxide may be used. This allows oxygen to be contained in the insulating layer 212. Ion implantation, ion doping, plasma immersion ion implantation, plasma processing, etc. Oxygen may be introduced into the insulating layer 212 by this method.

[0181] The oxygen contained in the insulating layer 212 is partially transmitted through the insulating layer 261 by heat treatment or the like, and is transferred to the semiconductor layer The channel region of the semiconductor layer 231 is supplied with oxygen. In the case of a compound semiconductor, oxygen vacancies in the channel region can be reduced. The channel region of the semiconductor layer 231 can be made highly resistive, and the electrical characteristics of the transistor can be changed. This can suppress vibration and improve reliability.

[0182] For example, when an oxide conductor is used as the conductive layer 262, the insulating layer 212 and the like contain Oxygen may diffuse into the conductive layer 262, causing the conductive layer 262 to have a high resistance. The conductive layer 232 is made of a material that is difficult for oxygen to permeate. The oxygen contained in the conductive layer 262 is difficult to be supplied to the conductive layer 262. Even when a conductive material is used, the resistance of the conductive layer 262 can be prevented from increasing.

[0183] Next, the insulating layer 214 is formed. After that, the insulating layer 215 is formed. After that, chemical mechanical polishing (CMP) The insulating layer 215 is subjected to planarization treatment by a method such as (g) (FIG. 9(A)).

[0184] Next, openings are formed in the insulating layers 215, 214, and 212 down to the conductive layer 232. An opening is then formed that reaches the wiring 65 and the insulating layer 66. Then, a conductive layer is formed, and the conductive layer is lithographically The pixel electrode 111 and the conductive layer 251 are formed by processing using a lithography method or the like. The pixel electrodes are connected to the insulating layer 215, the insulating layer 214, and the insulating layer 212 through openings. The electrode 111 is electrically connected to the conductive layer 232, and the conductive layer 251 is electrically connected to the wiring 65. As described above, the pixel electrode 111 is made of a material that has a function of transmitting visible light. is used.

[0185] Next, an alignment film 133a is formed to cover the pixel electrodes 111 (FIG. 9(B)). On the substrate 61, a light-shielding layer 132, a colored layer 131, an overcoat 121, and a common electrode 112 are formed. As described above, the common electrode 112 is formed on the substrate 111, and the alignment film 133b is formed on the substrate 111 (FIG. 9(C)). Therefore, a material that has the function of transmitting visible light is used.

[0186] Furthermore, an adhesive layer 14 is formed between the substrate 51 shown in FIG. 9(B) and the substrate 61 shown in FIG. 9(C). 1 is used to seal the liquid crystal layer 113. Then, the connector 242, the FPC 72, and the polarizer 130 is formed. In this way, the display device 100 having the configuration shown in FIG. do.

[0187] As described above, in the method for manufacturing a display device according to one embodiment of the present invention, the transistor 206 is The semiconductor layer 231 and the conductive layer 262 of the capacitor element 34 are formed in the same process. In addition, an insulating layer that functions as a channel protection layer of the transistor 206 and The insulating layer 261 and the insulating layer having the function as the dielectric layer of the capacitance element 34 are formed in one process. The source electrode or the drain electrode of the transistor 206 can be formed of a conductive layer having a function as the other electrode of the capacitor element 34; The conductive layer 232 can be formed in one step. The manufacturing process of the display device 100 can be simplified, and the manufacturing cost of the display device 100 can be reduced. This can be done.

[0188] As described above, the conductive layer 262 and the conductive layer 232 have the function of transmitting visible light. This makes it possible to increase the aperture ratio of the pixel 900 of the display device 100. The higher the aperture ratio, the higher the light extraction efficiency can be, and therefore the power consumption of the display device 100 can be reduced. Furthermore, the image displayed by the display device 100 can be made higher in definition. can be done.

[0189] <4. Example of pixel arrangement> 10A and 10B show examples of the arrangement of a pixel 900 and the sub-pixels that the pixel 900 has. In Fig. 10(A) and (B), the red subpixel R, the green subpixel G, and the blue subpixel B 10(A) and 10(B), a plurality of scanning lines 81 are arranged to form one pixel. extend in the x direction, a plurality of signal lines 82 extend in the y direction, and the scanning lines 81 and the signal The lines 82 intersect.

[0190] As shown in the dashed double-dashed line frame in FIG. 10A, the subpixel includes a transistor 206, a capacitor element 34, and the liquid crystal element 40. The gate electrode of the transistor 206 is connected to the scan line 81. One of the source electrode and the drain electrode of the transistor 206 is electrically connected to The first electrode is electrically connected to the signal line 82, and the second electrode is electrically connected to the second electrode of the capacitor element 34 and the liquid crystal element The first electrode of the capacitor element 34 and the liquid crystal element 40 are electrically connected to each other. A constant potential is applied to each of the first electrodes.

[0191] 10A and 10B show an example in which source line inversion driving is applied. Signals A1 and B2 are signals with the same polarity. Signals B1 and B2 are signals with the same polarity. Signal B1 is a signal with a polarity opposite to that of the signal A2. Signal A2 and signal B2 are signals with a polarity opposite to that of the signal B2. The number is.

[0192] As the resolution of display devices increases, the distance between sub-pixels becomes smaller. As shown in the dashed line frame of FIG. 1, the signal B1 is input to the sub-pixel to which the signal A1 is input. In the vicinity of the signal line 82, the liquid crystal is easily affected by the potentials of both the signal A1 and the signal B1. This makes the liquid crystal more susceptible to poor alignment.

[0193] In FIG. 10A, the direction in which multiple sub-pixels exhibiting the same color are arranged is the y direction, The direction is approximately parallel to the direction in which the signal line 82 extends. A sub-pixel of a different color is adjacent to the long side of the sub-pixel.

[0194] In FIG. 10B, the direction in which multiple sub-pixels exhibiting the same color are arranged is the x direction, As shown in the dashed line frame in FIG. 10(B), the secondary wiring 81 intersects with the direction in which the signal line 82 extends. Sub-pixels of the same color are adjacent to the short sides of a pixel.

[0195] As shown in FIG. 10B, in the subpixel, a side that is approximately parallel to the direction in which the signal line 82 extends is However, when the side is short, the alignment of the liquid crystal is more likely to be poor than when the side is long (FIG. 10(A)). As shown in FIG. 10(B), the alignment defect of the liquid crystal is easily caused. When a pixel is located between sub-pixels of the same color, a pixel located between sub-pixels of different colors is also located. In comparison with the case where the display device is turned on (FIG. 10(A)), the display defect is less likely to be visually recognized by the user of the display device. In one embodiment of the present invention, the direction in which a plurality of sub-pixels exhibiting the same color are arranged is the direction in which the signal lines It is preferable that 82 intersects the direction of extension.

[0196] <5. Display Device Configuration Example 3> One embodiment of the present invention is a display device (an input / output device or a touch panel) equipped with a touch sensor. The configuration of each of the above-described display devices can be applied to a touch panel. In this embodiment, an example in which a touch sensor is mounted on the display device 100 will be mainly described. explain.

[0197] There is no limitation on the detection elements (also referred to as sensor elements) included in the touch panel of one embodiment of the present invention. Various sensors that can detect the proximity or contact of a sensing object such as a finger or stylus, It can be used as a sensing element.

[0198] The sensor type may be, for example, a capacitance type, a resistive film type, a surface acoustic wave type, or an infrared type. Various methods such as a pressure-sensitive method, an optical method, or the like can be used.

[0199] In this embodiment, a touch panel having a capacitance type detection element will be described as an example. .

[0200] The capacitance type includes a surface capacitance type, a projected capacitance type, etc. The capacitance type includes the self-capacitance type and the mutual capacitance type. This is preferable because it enables simultaneous multi-point detection.

[0201] The touch panel of one embodiment of the present invention is formed by bonding a display device and a sensing element that are separately manufactured. A detector element is formed on one or both of a substrate supporting a display element and an opposing substrate. Various configurations can be applied, such as a configuration in which electrodes or the like are provided.

[0202] 11 and 12 show examples of touch panels. FIG. 11(A) shows a touch panel 35 11(B) is a perspective view of FIG. 11(A). For clarity, only representative components are shown. In FIG. 11(B), the substrate 61 and The substrate 162 is shown by a dashed line, with only the outline clearly indicated. FIG. 12 is a cross-sectional view of the touch panel 350. do.

[0203] The touch panel 350 is configured by bonding together a display device and a sensing element that are fabricated separately. do.

[0204] The touch panel 350 has an input device 375 and a display device 370, which are set up one on top of the other. It is being used.

[0205] The input device 375 includes a substrate 162, an electrode 127, an electrode 128, a plurality of wirings 137, and a plurality of The FPC 72b has a plurality of wirings 137 and a plurality of wirings 138. Each is electrically connected. IC 73b is mounted on FPC 72b.

[0206] The display device 370 has a substrate 51 and a substrate 61 that are provided opposite each other. The substrate 51 has a display section 62 and a drive circuit section 64. Wiring 65 and the like are provided on the substrate 51. The FPC 72a is electrically connected to the wiring 65. The FPC 72a has an IC 73a is provided.

[0207] Signals and power are supplied to the display unit 62 and the drive circuit unit 64 through wiring 65. The signal and power are input to the wiring 65 from the outside or IC 73a via the FPC 72a. will be done.

[0208] FIG. 12 shows a region including the pixel 900, the driving circuit section 64, and the FPC 72a, and a region including the FPC 72b. FIG.

[0209] The substrate 51 and the substrate 61 are bonded together by an adhesive layer 141. The substrate 51 and the substrate 61 are bonded together by an adhesive layer 169. Each layer in the figure corresponds to the display device 370. In addition, each layer from the substrate 162 to the electrode 124 The adhesive layer 169 corresponds to the input device 375. It can be said that the two are pasted together.

[0210] The configuration of the display device 370 shown in FIG. 12 is the same as that of the display device 100 shown in FIG. Therefore, detailed explanation will be omitted.

[0211] A polarizing plate 165 is attached to the substrate 51 by an adhesive layer 167. A backlight 161 is attached to the display panel 5 by an adhesive layer 163.

[0212] The backlight 161 may be a direct type backlight or an edge light type backlight. When a direct backlight with LEDs is used, complex local This is preferable because it allows dimming and improves contrast. By using a backlight, the thickness of the module including the backlight can be reduced. Furthermore, quantum dots may be used as the backlight 161.

[0213] Quantum dots are semiconductor nanocrystals with a size of a few nanometers, and are 1×10 3 Pieces to 1×10 6 Quantum dots are composed of about 100 atoms. The energy shift of quantum dots is dependent on their size. Therefore, even quantum dots made of the same material will have different emission wavelengths depending on their size. The emission wavelength can be easily adjusted by changing the size of the quantum dots used. can.

[0214] In addition, quantum dots have a narrow peak width in the emission spectrum, making it possible to obtain light emission with good color purity. Furthermore, the theoretical external quantum efficiency of quantum dots is said to be nearly 100%. This is much higher than the 25% of organic compounds that exhibit fluorescence, and This indicates that quantum dots can be used as light-emitting materials. In addition, quantum dots, which are inorganic compounds, Since the inherent stability is also excellent, it is possible to obtain a light emitting device that is preferable in terms of life. can be done.

[0215] The materials that make up quantum dots include elements in group 14 of the periodic table, elements in group 15 of the periodic table, and Group 16 elements, compounds consisting of multiple Group 14 elements, Groups 4 to 1 Compounds of elements in Group 4 and Group 16 of the periodic table, and compounds of elements in Group 2 and Group 16 of the periodic table Compounds with elements, compounds with elements in group 13 of the periodic table and elements in group 15 of the periodic table, compounds with elements in group 13 of the periodic table Compounds of elements and elements from Group 17 of the periodic table, compounds of elements from Group 14 of the periodic table and elements from Group 15 of the periodic table compounds of elements in Group 11 of the periodic table and elements in Group 17 of the periodic table, iron oxides, titanium oxides, Examples include chalcogenide spinels and various semiconductor clusters.

[0216] Specifically, cadmium selenide, cadmium sulfide, cadmium telluride, zinc selenide , zinc oxide, zinc sulfide, zinc telluride, mercury sulfide, mercury selenide, mercury telluride, arsenide Indium, indium phosphide, gallium arsenide, gallium phosphide, indium nitride, gallium nitride Sodium, indium antimonide, gallium antimonide, aluminum phosphide, aluminum arsenide Aluminum, aluminum antimonide, lead selenide, lead telluride, lead sulfide, lead selenide Indium, indium telluride, indium sulfide, gallium selenide, arsenic sulfide, selenium arsenic telluride, arsenic sulfide, antimony selenide, antimony telluride, sulfur Bismuth oxide, 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, calcium sulfide, calcium selenide, calcium telluride, beryllium sulfide, Beryllium telluride, beryllium sulfide, magnesium selenide, sulfur Germanium oxide, germanium selenide, germanium telluride, tin sulfide, tin selenide, Tin telluride, lead oxide, copper fluoride, copper chloride, copper bromide, copper iodide, copper oxide, copper selenide, oxide Nickel, cobalt oxide, cobalt sulfide, iron tetroxide, iron sulfide, manganese oxide, molybdenum sulfide Butane, vanadium oxide, tungsten oxide, tantalum oxide, titanium oxide, zirconium oxide ammonium, silicon nitride, germanium nitride, aluminum oxide, barium titanate, selenium and Compounds of zinc and cadmium, compounds of indium, arsenic and phosphorus, compounds of cadmium, selenium and sulfur Yellow compound, Cadmium, Selenium and Tellurium compound, Indium, Gallium and Arsenic compound compounds of indium, gallium and selenium; compounds of indium, selenium and sulfur; copper and Examples include, but are not limited to, compounds of indium and sulfur and combinations thereof. In addition, the composition is expressed in an arbitrary ratio, so-called alloy quantum dots For example, alloy quantum dots of cadmium, selenium, and sulfur may be used. By changing the ratio, the emission wavelength can be changed, which is effective for obtaining blue light. It is one of the means.

[0217] Quantum dot structures include core type, core-shell type, and core-multishell type. Either of these can be used, but it is also possible to cover the core with another inorganic material with a wider band gap. By forming a shell with This significantly improves the quantum efficiency of light emission, making it possible to reduce the influence of the core. It is preferable to use shell-type or core-multishell type quantum dots. Examples include zinc sulfide and zinc oxide.

[0218] In addition, quantum dots have a high proportion of surface atoms, making them highly reactive and prone to aggregation. Therefore, a protective agent or a protective group is attached to the surface of the quantum dots. It is preferable that the protecting agent is attached or the protecting group is provided. This prevents aggregation and increases solubility in solvents. It is also possible to improve the chemical stability. Examples of the protecting agent (or protecting group) include poly(ethylene glycol). Polyoxyethylene lauryl ether, Polyoxyethylene stearyl ether, Polyoxyethylene Polyoxyethylene alkyl ethers such as diethylene oleyl ether, tripropyl Phosphine, tributylphosphine, trihexylphosphine, trioctylphosphine trialkylphosphines such as polyoxyethylene n-octylphenyl ether, poly polyoxyethylene alkylphenyl ether, etc. Ethers, tri(n-hexyl)amine, tri(n-octyl)amine, tri(n-decyl)amine tertiary amines such as tripropylphosphine oxide, tributylphosphine Phosphine oxide, trihexylphosphine oxide, trioctylphosphine oxide, Organophosphorus compounds such as decylphosphine oxide, polyethylene glycol dilaurate polyethylene glycol diesters such as polyethylene glycol distearate, In addition, organic nitrogenation of nitrogen-containing aromatic compounds such as pyridine, lutidine, collidine, and quinolines Compounds, hexylamine, octylamine, decylamine, dodecylamine, tetradecyl Aminoalkanes such as amine, hexadecylamine, and octadecylamine, dibutyl sulfite dialkyl sulfides such as dimethyl sulfoxide and dibutyl sulfoxide, Dialkyl sulfoxides, sulfur-containing aromatic compounds such as thiophene, and other organic sulfur compounds, Higher fatty acids such as lumitic acid, stearic acid, and oleic acid, alcohols, and sorbitan fats Acid esters, fatty acid modified polyesters, tertiary amine modified polyurethanes, polyethylene Examples of suitable amines include amines, amines, and amines.

[0219] As quantum dots become smaller, their band gaps become larger, so they can emit light at the desired wavelength. The size of the crystal is adjusted accordingly to obtain the desired amount of light. The emission of quantum dots is shifted to the blue side, i.e., to the higher energy side, By varying the size, wavelength regions in the ultraviolet, visible, and infrared regions of the spectrum can be achieved. The emission wavelength can be adjusted over a wide range. The size (diameter) of quantum dots is 0. A range of 5 nm to 20 nm, preferably 1 nm to 10 nm, is commonly used. The narrower the size distribution of quantum dots, the narrower the emission spectrum and the more pure the color. The shape of the quantum dots is not particularly limited, and may be spherical, The quantum dots may be rod-shaped, disk-shaped, or have other shapes. Since quantum rods emit light polarized in the c-axis direction, This makes it possible to obtain a light emitting device with better external quantum efficiency.

[0220] A polarizing plate 166 is attached to the substrate 162 by an adhesive layer 168. A protection substrate 160 is attached to the substrate 66 by an adhesive layer 164. When the touch panel 350 is assembled, the protection board 160 is The protective substrate 160 may be used as a substrate that is directly touched. The protection substrate 160 can be applied to the substrate 51 and the A structure in which a protective layer is formed on the surface of a substrate that can be used for the substrate 61, etc., or reinforced glass It is preferable to use a protective layer such as a ceramic coating. Alternatively, the protective layer may be made of silicon oxide, aluminum oxide, yttrium oxide, yttrium oxide, or yttrium oxide. It can be formed using an inorganic insulating material such as thoria stabilized zirconia (YSZ).

[0221] A polarizing plate 166 may be disposed between the input device 375 and the display device 370. In this case, as shown in FIG. 2, the protective substrate 160, the adhesive layer 164, and the adhesive layer 168 may not be provided. In this case, the substrate 162 can be positioned on the top surface of the touch panel 350. It is preferable to use a material that can be used for the protection substrate 160 described above for the protection substrate 62 .

[0222] An electrode 127 and an electrode 128 are provided on the substrate 61 side of the substrate 162. The insulating layer 125 is formed on the same plane as the electrodes 127 and 128. The electrode 124 is provided so as to cover the electrode 128. The electrode 124 is provided through an opening in the insulating layer 125. The electrode 127 is electrically connected to two electrodes 128 disposed on either side of the electrode 127 via the .

[0223] Among the conductive layers of the input device 375, the conductive layers (electrodes 127, 1 28, etc.) use a material that transmits visible light.

[0224] The wiring 137 obtained by processing the same conductive layer as the electrodes 127 and 128 is the same as the electrode 124. The conductive layer 126 is connected to the conductive layer 126 obtained by processing the conductive layer 24. 2b and is electrically connected to FPC 72b.

[0225] This embodiment mode can be combined with other embodiment modes as appropriate. In the case where multiple configuration examples are shown in one embodiment, the configuration examples may be combined as appropriate. It is possible to do this.

[0226] (Embodiment 2) In this embodiment, operation modes that can be performed in a display device of one embodiment of the present invention are illustrated. 13 will be used to explain.

[0227] In the following, we will assume that the device operates at a normal frame frequency (typically 60Hz or higher and 240Hz or lower). There are two operating modes: Normal mode, which operates at a low frame rate, and Low mode, which operates at a low frame rate. The idle stop (IDS) driving mode will be explained as an example.

[0228] In the IDS drive mode, after the image data writing process is executed, the image data is written. This refers to a driving method that stops the switching of image data. By extending the interval between writing of image data, the time required to write image data during that time can be reduced. The IDS drive mode can reduce power consumption by the amount of power consumed. The frame frequency can be set to about 1 / 100 to 1 / 10 of the normal frame rate. The video signal is the same between frames. Therefore, the IDS driving mode can display a still image. This is particularly effective when displaying images using IDS driving, which reduces power consumption. This reduces noise, suppresses screen flicker, and reduces eye strain.

[0229] 13(A), (B), and (C) show the pixel circuit and the normal drive mode and the IDS drive mode. 13A is a timing chart illustrating the operation of the first display element 50. 1 (here, a reflective liquid crystal element) and a pixel circuit electrically connected to the first display element 501. 13A, the pixel circuit 506 includes a signal line SL a gate line GL; a transistor M1 connected to the signal line SL and the gate line GL; Capacitance element Cs connected to transistor M1 LC The first display element One electrode of 501, one of the source and drain of the transistor M1, and a capacitance element Cs LC The node to which is connected is defined as node ND1.

[0230] The transistor M1 is connected to the capacitance element Cs LC This can be a leak path for data D1 stored in Therefore, it is preferable that the off-state current of the transistor M1 is as small as possible. In this case, it is preferable to use a transistor having a metal oxide in a semiconductor layer in which a channel is formed. It is preferable that the metal oxide has at least one of an amplifying function, a rectifying function, and a switching function. When the metal oxide has a metal oxide semiconductor, the metal oxide is called a metal oxide semiconductor. conductor) or oxide semiconductor , or OS for short. Below, we will introduce a typical example of a transistor in which a channel is formed. A transistor using an oxide semiconductor for a semiconductor layer (also called an OS transistor) ) will be used to explain the OS transistor. The transistor M1 also has the feature of having extremely low leakage current (off-state current) when in a non-conducting state. By using an OS transistor, the charge supplied to the node ND1 can be retained for a long period of time. can be done.

[0231] In the circuit diagram shown in FIG. 13A, the liquid crystal element LC serves as a leak path for the data D1. Therefore, to perform IDS driving properly, the resistivity of the liquid crystal element LC must be set to 1.0×10 1 4 It is preferable to set it to Ω·cm or more.

[0232] The channel region of the OS transistor is formed of, for example, In—Ga—Zn oxide, I In-Ga-Zn oxide can be preferably used. A typical composition is In:Ga:Zn=4:2:4.1 [atomic ratio]. It is possible.

[0233] FIG. 13B shows the signals applied to the signal line SL and the gate line GL in the normal drive mode. 1 is a timing chart showing the waveform of a signal. In the normal drive mode, the normal frame frequency ( If one frame period is represented by periods T1 to T3, then each frame During the scan period, a scanning signal is applied to the gate line GL, and data D1 is sent from the signal line SL to the node ND1. This operation is performed when the same data D1 is written from the period T1 to T3. The same applies when writing different data.

[0234] On the other hand, FIG. 13C shows the signal line SL and the gate line GL in the IDS drive mode. 1 is a timing chart showing the waveform of a signal applied to the IDS drive. One frame period is represented by the period T1, and the data The write period is T W , the data retention period is period T RET The IDS driving mode is , period T W A scanning signal is applied to the gate line GL, and data D1 of the signal line SL is transferred to the capacitance element Cs L C Write to period T RET The gate line GL is fixed to a low level voltage, and the transistor M1 is set to a non-conductive state, and the data D1 that was written is transferred to the capacitance element Cs LC The action to be held The low frame frequency is, for example, 0.1 Hz or more and less than 60 Hz. Alternatively, the frequency may be set to, for example, 0.1 Hz or more and less than 20 Hz.

[0235] This embodiment mode can be combined with other embodiment modes as appropriate.

[0236] (Embodiment 3) In this embodiment, an example of a method for driving a touch sensor will be described with reference to the drawings.

[0237] <Example of sensor detection method> FIG. 14(A) is a block diagram showing the configuration of a mutual capacitance type touch sensor. In FIG. 14(A), a pulse voltage output circuit 551 and a current detection circuit 552 are shown. In A), an electrode 521 to which a pulse voltage is applied and an electrode 522 to which a change in current is detected are arranged. Each of these is shown as six wires, X1 to X6 and Y1 to Y6. (A) illustrates a capacitance 553 formed by overlapping an electrode 521 and an electrode 522. The functions of electrode 521 and electrode 522 may be interchangeable.

[0238] The pulse voltage output circuit 551 is a circuit for applying a pulse voltage to the wirings X1 to X6 in order. When a pulse voltage is applied to the wirings X1 to X6, a capacitance 553 is formed. An electric field is generated between the electrodes 521 and 522. The electric field generated between the wirings is suppressed by shielding or the like. The proximity or contact of the object to be detected is detected by causing a change in the mutual capacitance of the quantity 553. It can be put out.

[0239] The current detection circuit 552 detects the current flowing through the wirings Y1 to Y6 due to a change in mutual capacitance at the capacitor 553. This is a circuit for detecting changes in current. The wiring from Y1 to Y6 detects the proximity or The detected current value does not change if there is no contact, but it changes when the object to be detected approaches or comes into contact with the object. If the mutual capacitance decreases, a decrease in the current value is detected. This can be done using an integrating circuit or the like.

[0240] In addition, one or both of the pulse voltage output circuit 551 and the current detection circuit 552 may be For example, the display section 62 and the drive circuit section 63 may be formed on the substrate 51 or the substrate 61 shown in FIG. 64, etc., can simplify the process and also can form the This is preferable because it reduces the number of components required. One or both of the current sensing circuits 552 may be implemented in IC73.

[0241] In particular, as a transistor formed on the substrate 51, a multi-crystal layer is formed in a semiconductor layer in which a channel is formed. When crystalline silicon such as crystalline silicon or single crystal silicon is used, the pulse voltage output circuit 551 The driving capability of the circuits such as the current detection circuit 552 is improved, and the sensitivity of the touch sensor is improved. This can be done.

[0242] FIG. 14B shows input and output waveforms of the mutual capacitance type touch sensor shown in FIG. 14A. In FIG. 14(B), the detection object in each row and column is detected in one frame period. In addition, in FIG. 14(B), when the object to be detected is not detected (non-touch ) and when detecting an object to be detected (touch). For the wiring from Y1 to Y6, waveforms are shown in which the voltage values ​​correspond to the detected current values.

[0243] A pulse voltage is applied to the wires X1-X6 in order, and the voltages Y1 to Y6 are The waveform on the Y6 wiring changes. When there is no proximity or contact of the object to be sensed, X1 to X The waveforms of Y1 to Y6 change uniformly according to the change in the voltage of the wire 6. In areas where they are close to or in contact with each other, the current value decreases, and the waveform of the corresponding voltage value also changes. To become.

[0244] In this way, by detecting the change in mutual capacitance, the proximity or contact of the object to be detected can be detected. It is possible.

[0245] <Example of a display device driving method> FIG. 15(A) is a block diagram showing an example of the configuration of a display device. A scanning line driving circuit GD (scanning line driving circuit), a source driving circuit SD (signal line driving circuit), a plurality of pixel p 15A shows a display unit having ix. In addition, in FIG. 15A, the gate drive circuit GD is electrically The gate lines x_1 to x_m (m is a natural number) connected to the source driver circuit SD are electrically connected to the In the pixel pix, the source lines y_1 to y_n (n is a natural number) are connected. These are labeled (1,1) through (n,m).

[0246] FIG. 15(B) shows the voltage applied to the gate lines and source lines in the display device shown in FIG. 15(A). FIG. 15B is a timing chart of a data signal. The diagram shows two cases: one where the data signal is rewritten and one where the data signal is not rewritten. 15(B) does not take into account periods such as flyback periods.

[0247] When the data signal is rewritten every frame period, the gate lines x_1 to x_m are During the horizontal scanning period 1H, when the scanning signal is at H level, A data signal D is applied to the column source lines y_1 to y_n.

[0248] If the data signal is not rewritten every frame period, the data signal is applied to the gate lines x_1 to x_m. In the horizontal scanning period 1H, the scanning signal to the source lines y_1 to y_n of each column is stopped. Stop giving data signals.

[0249] The driving method in which the data signal is not rewritten for each frame period is, in particular, Effective when oxide semiconductors are used in the semiconductor layer where the channel is formed as a transistor A transistor using an oxide semiconductor is different from a transistor using a semiconductor such as silicon. It is possible to make the off-state current extremely small compared to that of a conventional transistor. The data signal written in the previous period is retained without being rewritten for each period. For example, the gray level of a pixel can be maintained for 1 second or more, preferably 5 seconds or more. It is also possible.

[0250] In addition, a polycrystalline silicon is used in a semiconductor layer in which a channel is formed as a transistor in the pixel pix. When applying a capacitor, the size of the storage capacitance of the pixel is increased in advance. The larger the storage capacitance, the longer the gray level of the pixel can be maintained. The size of the storage capacitor can be determined by the resistors of the transistors and display elements electrically connected to the storage capacitor. For example, the storage capacitance per pixel should be set to 5fF or more. F or less, preferably 10 fF to 5 pF, more preferably 20 fF to 1 pF. This allows the data signal to be written in the previous frame without being rewritten every frame. The data signal can be held for a period of, for example, several frames or several tens of frames. This makes it possible to maintain the gradation of the pixel.

[0251] <Example of how to drive the display and touch sensor> 16A to 16D show an example of the touch sensor described in FIGS. 14A and 14B. When the display unit described in FIGS. 15(A) and 15(B) is driven for 1 second, 16A is a diagram illustrating the operation during a frame period in which one Frame period is 16.7ms (frame frequency: 60Hz), 1 frame of the touch sensor The period is shown as 16.7 ms (frame frequency: 60 Hz).

[0252] In the display device according to one embodiment of the present invention, the operation of the display unit and the operation of the touch sensor are independent of each other. Therefore, a touch detection period can be set in parallel with the display period. As shown in the figure, the frame period for both the display and touch sensor is set to 16.7 ms (frame period The frame frequency of the touch sensor and the display can be set to 60Hz. For example, as shown in FIG. 16B, one frame period of the display unit may be set to 8 1.3ms (frame frequency: 120Hz), and 1 frame period of the touch sensor is set to 1. It can also be set to 6.7 ms (frame frequency: 60 Hz). The frame frequency of the display may be set to 33.3 ms (frame frequency: 30 Hz).

[0253] The display unit is also configured to be switchable in frame frequency, so that when displaying moving images, the frame Increase the frequency (for example, 60Hz or more or 120Hz or more) when displaying a still image. reduce the frame frequency (for example, below 60Hz, below 30Hz, or below 1Hz). By doing so, the power consumption of the display device can be reduced. The frame frequency can be switched between standby and when a touch is detected. It is okay to let it happen.

[0254] Furthermore, in the display device of one embodiment of the present invention, data signals are not rewritten in the display portion, and the display device can display the previous data. By holding the data signal rewritten during this period, one frame period of the display is extended to 16.7ms. Therefore, as shown in FIG. 16(C), One frame period is set to 1 sec. (frame frequency: 1 Hz), and one frame of the touch sensor is The frame period can also be set to 16.7 ms (frame frequency: 60 Hz).

[0255] In addition, the data signal rewritten in the previous period is not rewritten in the display unit. For the configuration to hold the signal, please refer to the IDS drive mode explained earlier. Regarding the IDS drive mode, the rewriting of the data signal on the display is limited to a specific area. The partial IDS drive mode may be a partial IDS drive mode in which only the The data signal is rewritten only in a specific area, and in other areas, the data signal is rewritten in the same way as in the previous period. This is a configuration for holding the rewritten data signal.

[0256] Furthermore, according to the touch sensor driving method disclosed in this embodiment, the driving method shown in FIG. When the touch sensor is operated, the touch sensor can be continuously driven. ) at the timing when the proximity or contact of the object to be detected is detected. It is also possible to rewrite the data signals on the display unit.

[0257] Here, if a data signal rewrite operation is performed on the display unit during the sensing period of the touch sensor, Noise generated when rewriting data signals is transmitted to the touch sensor, Therefore, the period during which the data signal is rewritten on the display unit may be shortened. It is preferable to drive the touch sensor so that the sensing period of the touch sensor is shifted.

[0258] In FIG. 17(A), the rewriting of the data signal of the display unit and the sensing of the touch sensor are interchanged. 17B shows an example in which the rewriting operation of the data signal of the display unit is performed. This example shows that the touch sensor is sensed once for every two times. A configuration in which touch sensor sensing is performed once for every three or more rewrite operations, including but not limited to It may also be possible to use the following.

[0259] In addition, the transistor applied to the pixel pix has an oxide in the semiconductor layer where the channel is formed. When using semiconductors, it is possible to significantly reduce the off-current, making it possible to rewrite data signals. Specifically, after the data signal is rewritten, Therefore, it is possible to provide a sufficiently long pause before the next data signal is rewritten. The pause period can be, for example, 0.5 seconds or more, 1 second or more, or 5 seconds or more. The upper limit of the pause period is limited by the capacitance connected to the transistor and the leakage current of the display element, etc. The time is limited to, for example, 1 minute or less, 10 minutes or less, 1 hour or less, or 1 day or less. can.

[0260] FIG. 17(C) shows an example in which the data signal of the display is rewritten once every five seconds. In FIG. 17(C), the display unit rewrites the data signal and then writes the next data signal. Before the rewrite operation, a pause period is provided during which the rewrite operation is stopped. So, the touch sensor operates at a frame frequency of iHz (i is the frame frequency of the display device or higher, As shown in Figure 17(C), the touch panel can be driven at a frequency of 0.2 Hz or more. The sensor sensing is performed during the rest period, and not during the period when the display data signal is being rewritten. This is preferable because it is possible to improve the sensitivity of the touch sensor. ) rewriting the data signal on the display and sensing the touch sensor are performed simultaneously. This simplifies the driving signals.

[0261] In addition, during the pause period when the data signal of the display unit is not rewritten, the data signal to the display unit is In addition to stopping the supply of signals, either the gate driver GD or the source driver SD is Furthermore, the gate drive circuit GD and the source drive circuit S may be turned off. You can also stop the power supply to one or both of D. This will reduce noise. This reduces the noise and improves the sensitivity of the touch sensor. This can further reduce the power consumption.

[0262] A display device according to one embodiment of the present invention has a structure in which a display portion and a touch sensor are sandwiched between two substrates. Therefore, the distance between the display unit and the touch sensor can be made extremely short. Noise generated when the display is in operation is more likely to be transmitted to the touch sensor, reducing its sensitivity. By applying the driving method exemplified in this embodiment, it is possible to achieve a thin and high Therefore, it is possible to realize a display device having a touch sensor that achieves both high detection sensitivity and high accuracy.

[0263] This embodiment mode can be combined with other embodiment modes as appropriate.

[0264] (Fourth embodiment) In this embodiment, a semiconductor layer of a transistor disclosed in one embodiment of the present invention can be used. The following describes metal oxides that can be used in the semiconductor layer of a transistor. In this case, the metal oxide may be interpreted as an oxide semiconductor.

[0265] Oxide semiconductors are classified into single-crystal oxide semiconductors and non-single-crystal oxide semiconductors. As a crystalline oxide semiconductor, CAAC-OS (c-axis-aligned crystals talline oxide semiconductor), polycrystalline oxide semiconductor, n c-OS(nanocrystalline oxide semiconductor ), pseudo-amorphous oxide semiconductor (a-like OS) oxide semiconductors), and amorphous oxide semiconductors.

[0266] In addition, a semiconductor layer of a transistor disclosed in one embodiment of the present invention may contain CAC-OS (Clo ud-Aligned Composite oxide semiconductor ) may also be used.

[0267] Note that the semiconductor layer of the transistor disclosed in one embodiment of the present invention may be formed using the above-described non-single-crystal oxide. A non-single-crystal oxide semiconductor or CAC-OS can be preferably used. As such, nc-OS or CAAC-OS can be preferably used.

[0268] Note that in one embodiment of the present invention, CAC-OS is preferably used for a semiconductor layer of a transistor. By using CAC-OS, it is possible to provide transistors with high electrical characteristics and high reliability. It can be granted.

[0269] The following provides details about CAC-OS.

[0270] CAC-OS or CAC-metal oxide is a material that has the function of conductivity and A part of the material has an insulating function, and the entire material has a semiconductor function. Note that CAC-OS or CAC-metal oxide is used as the channel of a transistor. When used in a region, the conductive function is to allow electrons (or holes) to flow as carriers. The insulating function is to prevent the flow of electrons, which act as carriers. By making the functions of the two complementary, the switching function (On / Off) This function (which turns off the power supply) is given to CAC-OS or CAC-metal oxide. In CAC-OS or CAC-metal oxide, By separating the functions, the functionality of both can be maximized.

[0271] Also, CAC-OS or CAC-metal oxide is used in conductive and insulating areas. The conductive region has the above-mentioned conductive function, and the insulating region has the above-mentioned insulating function. In addition, the conductive region and the insulating region in the material are formed by nanoparticle layers. The conductive and insulating regions may be separated by a bell. In addition, the conductive area may be observed as a cloud-like connected area with a blurred periphery. This may be the case.

[0272] In addition, in CAC-OS or CAC-metal oxide, the conductive region and the insulating region are The peripheral region is 0.5 nm to 10 nm, preferably 0.5 nm to 3 nm. The following sizes may be dispersed in the material:

[0273] In addition, CAC-OS or CAC-metal oxide has different band gaps. For example, CAC-OS or CAC-metal oxidized de is a component with a wide gap due to the insulating region and a component with a narrow gap due to the conductive region. In this configuration, when carriers flow, In the narrow gap component, carriers mainly flow. The component having a wide gap acts complementary to the component having a narrow gap. Carriers also flow into the wide-gap component in conjunction with the component with a wide gap. AC-OS or CAC-metal oxide is used for the channel region of the transistor. When the transistor is turned on, a high current driving force, i.e., a large on-state current, and Therefore, a high field effect mobility can be obtained.

[0274] That is, CAC-OS or CAC-metal oxide is a matrix composite material. (matrix composite) or metal matrix composite It can also be called atrix composite.

[0275] For example, the CAC-OS has elements that make up the metal oxide, and the elements are 0.5 nm or more and 10 nm or less. Preferably, it is a configuration of a material unevenly distributed in a size of 1 nm or more and 2 nm or less or in the vicinity thereof. In the following, we will refer to metal oxides in which one or more metal elements are unevenly distributed. The region having the metal element has a size of 0.5 nm to 10 nm, preferably 1 nm to 2 nm. A mixed state of particles with sizes of less than or close to 1 m is also called a mosaic or patch state.

[0276] The metal oxide preferably contains at least indium. In addition to these, aluminum, gallium, yttrium, and zinc are preferably contained. Sodium, copper, vanadium, beryllium, boron, silicon, titanium, iron, nickel, gel Al, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, It contains one or more selected from the group consisting of tantalum, tungsten, and magnesium. It's fine.

[0277] For example, CAC-OS made of In-Ga-Zn oxide (In-Ga-Zn oxide among CAC-OS) α-Zn oxide may be specifically referred to as CAC-IGZO. (Hereinafter, InO X1 (X1 is a real number greater than 0) or indium zinc oxide In X2 Zn Y2 O Z2 (X2, Y2, and Z2 are real numbers greater than 0) ) and gallium oxide (hereinafter referred to as GaO X3 (X3 is a real number greater than 0) . ), or gallium zinc oxide (Ga X4 ZnY4 O Z4 (X4, Y4, and Z4 is a real number greater than 0.) The material separates into a mosaic shape. , mosaic InO X1 , or In X2 Zn Y2 O Z2 The structure is uniformly distributed in the film. It is a cloud-like structure (hereinafter also referred to as a cloud-like structure).

[0278] In other words, CAC-OS is X3 The region where In is the main component and X2 Zn Y2 O Z2 , or InO X1 A composite metal oxide having a mixed structure with a region in which In this specification, for example, when the atomic ratio of In to the element M in the first region is , the atomic ratio of In to the element M in the second region is greater than the atomic ratio of In in the first region. The concentration of In is higher than in the region

[0279] IGZO is a common name and refers to a compound of In, Ga, Zn, and O. A typical example is InGaO3(ZnO) m1 (m1 is a natural number), or In ( 1+x0) Ga (1-x0) O3(ZnO) m0 (-1≦x0≦1, m0 is an arbitrary number) Examples of such crystalline compounds include:

[0280] The crystalline compounds may have a single crystal structure, a polycrystalline structure, or a c-axis alcove (CAAC) structure. The CAAC structure is a structure in which multiple IGZO The nanocrystals have a c-axis orientation and are connected without orientation in the ab plane. do.

[0281] On the other hand, CAC-OS is a material structure of metal oxide. In a material composition containing Zn and O, nanoparticles with Ga as the main component were observed in some areas. The region where In is observed as a nanoparticle and the region where In is observed as a nanoparticle are the main component are shown in the model. Therefore, in CAC-OS, the crystal structure Construction is a secondary element.

[0282] It should be noted that the CAC-OS does not include a laminated structure of two or more films with different compositions. For example, a structure consisting of two layers, one containing In as the main component and the other containing Ga as the main component, is not included. do not have.

[0283] In addition, GaO X3 The region where In is the main component and X2 Zn Y2 O Z2 , or InO X1 but In some cases, a clear boundary between the main component region and the main component region cannot be observed.

[0284] Instead of gallium, aluminum, yttrium, copper, vanadium, and beryllium can be used. , boron, silicon, titanium, iron, nickel, germanium, zirconium, molybdenum , lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium If one or more selected elements from the group consisting of sodium, etc. are included, CAC-OS will The region observed is a nanoparticle with the metal element as the main component, and a nanoparticle with In as the main component in part. The structure is such that the areas observed as particles and the areas observed as particles are randomly dispersed in a mosaic pattern. cormorant.

[0285] CAC-OS is formed by sputtering without intentionally heating the substrate. In addition, when the CAC-OS is formed by a sputtering method, the deposition gas is The gas is selected from an inert gas (typically argon), oxygen gas, and nitrogen gas. One or more of these may be used. The lower the flow rate ratio of the gas, the more preferable. For example, the flow rate ratio of oxygen gas is preferably 0% or more and less than 30%. It is more preferable to set the content to 0% or more and 10% or less.

[0286] CAC-OS is a type of X-ray diffraction (XRD) measurement method. When measured using the θ / 2θ scan by the out-of-plane method, In other words, from the X-ray diffraction, the measurement region It can be seen that no orientation in the ab plane direction or the c axis direction is observed.

[0287] In addition, the CAC-OS uses an electron beam with a probe diameter of 1 nm (also called a nanobeam electron beam). In the electron diffraction pattern obtained by irradiating the electron beam, a ring-shaped region with high brightness and the Therefore, the electron diffraction pattern indicates that CAC-OS The crystal structure is nc (nano-c) which has no orientation in the plane direction and cross-sectional direction. It can be seen that it has a crystal structure.

[0288] For example, in the case of CAC-OS, an In-Ga-Zn oxide, energy dispersive X-ray Energy Dispersive X-ray spectroscopy (EDX) EDX mapping obtained using a copy of the GaO X3 The region where is the principal component and , InX2 Zn Y2 O Z2 , or InO X1 The area where the main component is unevenly distributed and mixed. It can be confirmed that it has the structure shown in the figure.

[0289] CAC-OS has a structure different from that of IGZO compounds, in which metal elements are uniformly distributed. CAC-OS has different properties from ZO compounds. X3 The main components are In X2 Zn Y2 O Z2 , or InO X1 The area where is the principal component and It has a phase-separated structure with a mosaic of regions each consisting mainly of one element.

[0290] Here, In X2 Zn Y2 O Z2 , or InO X1 The region where is the main component is GaO X3 This is a region with high conductivity compared to the region where In is the main component. X2 Zn Y2 O Z2 , or InO X1 When carriers flow through the region where the oxide is the main component, Conductivity as a semiconductor is exhibited. X2 Zn Y2 O Z2 , or InO X1 The region where the main component is distributed in a cloud-like shape in the oxide semiconductor leads to a high field-effect transition. Mobility (μ) can be achieved.

[0291] On the other hand, GaO X3 The region where In etc. are the main components is X2 Zn Y2 O Z2 , or InO X1 This region has higher insulating properties than the region where GaO is the main component. X3 etc. are the main components The distribution of these regions in the oxide semiconductor suppresses leakage current and provides good switching performance. This allows for realizing a switching operation.

[0292] Therefore, when CAC-OS is used in a semiconductor device, GaO X3 and insulation due to I n X2 Zn Y2 O Z2 , or InO X1 The conductivity caused by the This allows for a high on-state current (I on ) and high field-effect mobility (μ). Cut.

[0293] Furthermore, semiconductor devices using CAC-OS are highly reliable. It is ideal for a variety of semiconductor devices, including displays.

[0294] This embodiment mode can be combined with other embodiment modes as appropriate.

[0295] (Embodiment 5) In this embodiment, an electronic device according to one embodiment of the present invention will be described.

[0296] Examples of electronic devices include television sets, desktop or notebook PCs, etc. Personal computers, computer monitors, digital cameras, digital video cameras digital photo frames, mobile phones, portable game consoles, personal digital assistants, sound reproduction equipment Examples include large gaming machines such as pachinko machines.

[0297] FIG. 18A shows a notebook personal computer, which includes a housing 8111 and a display unit 811 2, a keyboard 8113, a pointing device 8114, etc.

[0298] The display device of one embodiment of the present invention can be applied to the display portion 8112. It is possible to provide a notebook personal computer having a display with high image quality.

[0299] Figure 18(B) and (C) show the digital signage. The digital signage includes a housing 8000, a display unit 8001, and a screen. It also has a speaker 8003, etc., and an LED lamp, operation keys (power switch, or operation It may have a connection terminal, various sensors, a microphone, etc. .

[0300] FIG. 18(C) shows a digital signage attached to a cylindrical pillar.

[0301] The display device of one embodiment of the present invention is provided in the display portion 8001 shown in FIGS. This makes it possible to provide a digital signage having a display section with a high aperture ratio. can be done.

[0302] The larger the display area 8001, the more information can be displayed at one time. The wider the part 8001, the more noticeable it is, and for example, the more effective the advertisement. Cut.

[0303] By applying a touch panel to the display unit 8001, images or videos can be displayed on the display unit 8001. It is preferable because it not only shows the route information but also allows the user to operate it intuitively. When used to provide information such as traffic information, the user can operate the device intuitively. This can improve accessibility.

[0304] Fig. 18(D) shows the appearance of the car 7900. Fig. 18(E) shows the driving of the car 7900. The car 7900 includes a body 7901, wheels 7902, a windshield 7903, It has lights 7904, fog lights 7905, etc.

[0305] The display device of one embodiment of the present invention can be used for a display portion of an automobile 7900, for example. 18E, the display portions 7910 to 7917 are the display devices of one embodiment of the present invention. This allows for providing a vehicle with a display unit with a high aperture ratio. can be done.

[0306] The display unit 7910 and the display unit 7911 are provided on a windshield 7903 of the automobile 7900. In one embodiment of the present invention, an electrode included in a display device is formed using a light-transmitting conductive material. By fabricating it, it becomes a so-called see-through display device that can see through to the other side. If the display device is in a see-through state, it will be possible to see clearly even when driving a car 7900. Therefore, the display device 10 according to one embodiment of the present invention can be mounted on the vehicle 7900. The display device can be installed on the windshield 7903. When the transistor is provided, an organic transistor using an organic semiconductor material or an oxide semiconductor is used. A light-transmitting transistor such as a light-transmitting transistor may be used.

[0307] The display unit 7912 is provided on the pillar portion. The display unit 7913 is provided on the dashboard portion. The display unit 7914 is provided in the door portion. For example, By displaying an image from the imaging means on the display unit 7912, it is possible to Similarly, the display unit 7913 can complement the view that is obstructed by the dashboard. The display unit 7914 can complement the view that is blocked by the door. That is, by projecting an image from an imaging means provided on the outside of the vehicle, This can compensate for blind spots and increase safety. By projecting the image, safety checks can be performed more naturally and without any discomfort.

[0308] The display unit 7917 is provided on the handle. , or display unit 7917 displays navigation information, speedometer, tachometer, It can provide various information such as distance traveled, fuel amount, gear status, air conditioning settings, etc. In addition, the display items and layout displayed on the display can be adjusted to suit the user's preferences. The above information can be displayed on the display units 7910 to 7914. It can be displayed.

[0309] Note that the display portions 7910 to 7917 can also be used as lighting devices.

[0310] This embodiment mode can be combined with other embodiment modes as appropriate. [Explanation of symbols]

[0311] 10 Display device 10A display device 10B Display device 11 Circuit Board 12 PCB 13 Backlight unit 14 Transistor 15 Liquid crystal element 15A display device 15B Display device 15C Display device 16 Capacitor element 21 pixel electrode 22 Liquid crystal layer 23 Common electrode 25 Conductive layer 26 Insulating layer 27 Conductive layer 28 Conductive Layer 29 Connectors 31 Touch sensor unit 32 Insulating layer 33 Conductive layer 34 Capacitor element 40 Liquid crystal element 45a light 45b light 45c Light 51 PCB 61 PCB 62 Display section 64 Drive circuit section 65 Wiring 72 FPC 72a FPC 72b FPC 73 IC 73a IC 73b IC 81 scan lines 82 signal line 100 display device 111 pixel electrode 112 Common electrode 113 Liquid crystal layer 121 Overcoat 124 electrodes 125 Insulating Layer 126 Conductive Layer 127 Electrode 128 electrode 130 Polarizing Plate 131 Colored layer 132 Light blocking layer 133a Alignment film 133b Alignment film 137 Wiring 138 Wiring 141 Adhesive layer 160 Protection Board 161 Backlight 162 PCB 163 Adhesive layer 164 Adhesive layer 165 Polarizing Plate 166 Polarizing Plate 167 Adhesive layer 168 Adhesive layer 169 Adhesive layer 201 Transistor 204 Connection 206 Transistor 211 Insulating layer 212 Insulating layer 214 Insulating layer 215 Insulating Layer 221 Gate electrode 222 Conductive layer 223 Gate electrode 224 Conductive Layer 225 Conductive Layer 231 Semiconductor layer 232 Conductive layer 232a Semiconductor layer 242 Connectors 242b Connection 251 Conductive Layer 261 Insulating Layer 262 Conductive Layer 262a Semiconductor layer 350 touch panel 370 Display device 375 Input Device 501 Display element 506 pixel circuit 521 Electrode 522 Electrode 551 Pulse voltage output circuit 552 Current detection circuit 553 capacity 900 pixels 900s shading area 900t transmission area 902 Wiring 904 Wiring 918 Display area 918B Display area 918G display area 918R display area 7900 Automobiles 7901 Car body 7902 Wheel 7903 Windshield 7904 Light 7905 Fog lamp 7910 Display section 7911 Display section 7912 Display section 7913 Display section 7914 Display section 7915 Display section 7916 Display section 7917 Display section 8000 chassis 8001 Display section 8003 Speaker 8111 Housing 8112 Display section 8113 keyboard 8114 Pointing Device

Claims

[Claim 1] A display device including a transistor and a capacitor, The transistor is a first insulating layer; a first semiconductor layer in contact with the first insulating layer; a second insulating layer in contact with the first semiconductor layer; a first conductive layer electrically connected to the first semiconductor layer through an opening provided in the second insulating layer; the first semiconductor layer has a channel region; The capacitive element is a second conductive layer in contact with the first insulating layer; the second insulating layer in contact with the second conductive layer; the first conductive layer in contact with the second insulating layer, the second conductive layer has a similar composition to the first semiconductor layer; The display device, wherein the first conductive layer and the second conductive layer have a function of transmitting visible light.

Images