Display device

Abstract

To provide a display device, an electronic apparatus, or a lighting device that are hard to be damaged.SOLUTION: A first substrate having flexibility and a second substrate having flexibility are overlapped via a display element. A third substrate having flexibility is attached onto an external side of the first substrate, and a fourth substrate having flexibility is attached to an external side of the second substrate. The third substrate is formed of a material softener than that of the first substrate, The fourth substrate is formed of a material softener than that of the second substrate.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] One aspect of the present invention relates to an article, a method, or a manufacturing method. Process, machine, manufacture, or composition of matter In particular, one embodiment of the present invention relates to a light-emitting device, a display device, an electronic device, a lighting device, or This document relates to methods for making, using, and operating such devices. Light emission using the electroluminescence (EL) phenomenon Devices, displays, electronic devices, lighting devices, or methods for making, using, or operating them etc. [Background technology]

[0002] In recent years, light-emitting devices and display devices are expected to be used in a variety of applications, and diversification is required. There are.

[0003] For example, in light-emitting devices and display devices for mobile devices, etc., it is important that the device is thin and lightweight. There are demands for the material to be applicable to curved surfaces, be resistant to breakage, etc. There is a demand for light-emitting devices and display devices that can be bent at any location for the purpose of improving portability. are.

[0004] In addition, light-emitting elements (also referred to as EL elements) that utilize the EL phenomenon can be easily made thin and lightweight, and the input signal It has features such as high speed response to signals and can be driven using a low voltage DC power supply. Applications to display devices are being considered.

[0005] For example, Patent Document 1 discloses a thin film device formed on a silicon wafer or a glass substrate. The concept of transferring layers to a laminate of plastic substrates is disclosed. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-72050 Summary of the Invention [Problem to be solved by the invention]

[0007] Patent Document 1 lists materials for plastic substrates that can be used in display devices. However, some of these materials, such as fluororubber and silicone resin, are too flexible to be used in thin film devices. In addition, Patent Document 1 also mentions a material that is not suitable for transferring a glass layer. There is no mention of a preferred substrate material for use in such a display device.

[0008] One embodiment of the present invention is to provide a highly portable display device, electronic device, or lighting device. One of the objectives is to

[0009] Another embodiment of the present invention is a display device, an electronic device, or a lighting device that can be repeatedly bent. One of the purposes is to provide the following.

[0010] Another embodiment of the present invention is to provide a highly reliable display device, electronic device, or lighting device. One of the objectives is to

[0011] Another embodiment of the present invention provides a display device, an electronic device, or a lighting device that is less likely to be damaged. One of the objectives is to

[0012] Another embodiment of the present invention is to provide a display device, an electronic device, or a lighting device with low power consumption. One of the purposes of this project is to provide

[0013] Another embodiment of the present invention is to provide a novel display device, electronic device, or lighting device. One of the objectives is to

[0014] The description of these problems does not preclude the existence of other problems. It is not necessary for the present invention to solve all of these problems. The above will be made clear from the description, drawings, claims, etc. It is possible to extract other issues from the descriptions in the patent, claims, etc. [Means for solving the problem]

[0015] One aspect of the present invention is a semiconductor device having a first substrate, a second substrate, a third substrate, and a fourth substrate. The first substrate and the second substrate are overlapped with a display element interposed therebetween, and the third substrate and the fourth substrate are overlapped with a display element interposed therebetween. The first substrate and the second substrate are superimposed with each other, and the third and fourth substrates are superimposed with the first substrate and the second substrate. The display device is characterized in that the first substrate is softer than the second substrate.

[0016] One aspect of the present invention is a semiconductor device having a first substrate, a second substrate, a third substrate, and a fourth substrate. The first substrate and the second substrate are overlapped with each other through a display element, and the third substrate and the fourth substrate are overlapped with each other through a display element. The plates are superimposed through the first and second substrates, and the third and fourth substrates are a Young's modulus of the first substrate and a Young's modulus of the second substrate being smaller than that of the first substrate and the second substrate; is.

[0017] The Young's modulus of a suitable material for the first and second substrates is 1 GPa (1×10 9 Pa) Upper 100GPa (100×10 9 Pa) or less, preferably 2 GPa or more and 50 GPa or less, More preferably, it is 2 GPa or more and 20 GPa or less.

[0018] The Young's modulus of the material used for the third substrate and the fourth substrate is set to be equal to that of the material used for the first substrate and the second substrate. The Young's modulus is preferably 1 / 50 or less, more preferably 1 / 100 or less, of the Young's modulus of the material used, A ratio of 1 / 500 or less is even more preferable. [Effects of the Invention]

[0019] One embodiment of the present invention is to provide a highly portable display device, electronic device, or lighting device. This can be done.

[0020] Another embodiment of the present invention is a display device, an electronic device, or a lighting device that can be repeatedly bent. can be provided.

[0021] Another embodiment of the present invention is to provide a highly reliable display device, electronic device, or lighting device. It is possible.

[0022] Another embodiment of the present invention provides a display device, an electronic device, or a lighting device that is less likely to be damaged. It is possible.

[0023] Another embodiment of the present invention is to provide a display device, an electronic device, or a lighting device with low power consumption. It can be provided.

[0024] Another embodiment of the present invention is to provide a novel display device, electronic device, or lighting device. This can be done. [Brief explanation of the drawings]

[0025] [Figure 1] 1A to 1C illustrate one embodiment of a display device. [Figure 2] 10A and 10B are cross-sectional views illustrating examples of bending of a display device. [Figure 3]1A to 1C illustrate one embodiment of a display device. [Figure 4] 1A and 1B are a block diagram and a circuit diagram illustrating one embodiment of a display device. [Figure 5] 1A to 1C illustrate one embodiment of a display device. [Figure 6] 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing a display device. [Figure 7] 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing 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 to 1C are cross-sectional views illustrating an example of a method for manufacturing a display device. [Figure 11] 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing a display device. [Figure 12] 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing a display device. [Figure 13] 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing a display device. [Figure 14] 1A and 1B are cross-sectional views illustrating one embodiment of a display device. [Figure 15] 1A and 1B are cross-sectional views illustrating one embodiment of a display device. [Figure 16] 1A and 1B are cross-sectional views illustrating one embodiment of a display device. [Figure 17] 1A and 1B are cross-sectional views illustrating one embodiment of a display device. [Figure 18] 1A and 1B are cross-sectional views illustrating one embodiment of a display device. [Figure 19] 1A to 1C illustrate a configuration example of a light-emitting element. [Figure 20] 1A to 1C illustrate examples of electronic devices and lighting devices. [Figure 21] 1A to 1C illustrate examples of electronic devices. [Figure 22] 1A to 1C illustrate examples of electronic devices. [Figure 23] Photographs illustrating an embodiment. [Figure 24] 1A to 1C illustrate one embodiment of a display device. [Figure 25] 1A to 1C illustrate one embodiment of a display device. [Figure 26]1A to 1C illustrate one embodiment of a display device. [Figure 27] 1A and 1B are cross-sectional views illustrating one embodiment of a display device. [Figure 28] 1A and 1B are cross-sectional views illustrating one embodiment of a display device. [Figure 29] 1A and 1B are cross-sectional views illustrating one embodiment of a display device. [Figure 30] FIG. 1 is a cross-sectional view illustrating one embodiment of a lighting device. DETAILED DESCRIPTION OF THE INVENTION

[0026] The embodiments will be described in detail with reference to the drawings. The present invention is not limited to the above, and various modifications and variations in form and detail are possible without departing from the spirit and scope of the present invention. It will be readily understood by those skilled in the art that the present invention can be modified as follows. The present invention is not limited to the description of the embodiments shown below. In the configuration of the present invention, the same parts or parts having similar functions are designated by the same reference numerals in different drawings. These are commonly used, and repeated explanations will be omitted.

[0027] In each drawing described in this specification, the size of each component, the thickness of a layer, or the area is The figures may be exaggerated or abbreviated for clarity. It is not limited to the rule. It is important to make the drawing easy to understand, especially in top views (plan views) and perspective views. Therefore, descriptions of some components may be omitted.

[0028] In addition, the position, size, range, etc. of each component shown in the drawings are for the purpose of facilitating understanding of the invention. Therefore, the actual location, size, range, etc. may not be shown. The invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings. In the actual manufacturing process, resist masks, etc., may be unintentionally damaged by etching or other processes. However, in order to make it easier to understand, it may be omitted.

[0029] In this specification, ordinal numbers such as "first" and "second" are used to avoid confusion of components. It does not indicate any order or ranking such as the order of processes or stacking. In addition, even if a term is not accompanied by an ordinal number in this specification, etc., it is possible to avoid confusion of the constituent elements. To avoid this, ordinal numbers may be used in the claims.

[0030] In addition, the terms "electrode" and "wiring" used in this specification and the like do not limit the functionality of these components. For example, an "electrode" may be used as part of a "wiring." Furthermore, the terms "electrode" and "wiring" are used interchangeably to refer to the plural "electrodes" and "wirings." This also includes cases where the "line" is formed as a single unit.

[0031] In this specification, the terms "above" and "below" refer to the positional relationship of components directly above or below each other. For example, "electrode on insulating layer A" is not limited to being below and in direct contact with the insulating layer A. If the expression is "B", electrode B does not need to be formed directly on insulating layer A, The inclusion of other components between the edge layer A and the electrode B is not excluded.

[0032] The source and drain functions may also be different when using transistors with different polarities or when using circuits When the direction of the current changes during circuit operation, they are interchanged depending on the operating conditions. Therefore, it is difficult to determine which is the source and which is the drain. In this specification, the terms source and drain may be used interchangeably. Let's say.

[0033] In addition, in this specification, "electrically connected" means "something that has some kind of electrical effect." This includes cases where the device is connected via a " is not subject to any particular restrictions as long as it enables the transmission and reception of electrical signals between connected objects. Therefore, even when it is expressed as "electrically connecting," in an actual circuit, In some cases, there are no physical connections and only wires running.

[0034] In addition, in this specification, "parallel" means that two straight lines are at an angle of -10° or more and 10° or less. Therefore, it also includes the case where the angle is between -5° and 5°. "Perpendicular" and "orthogonal" mean two lines that are arranged at an angle of 80° or more and 100° or less. Therefore, it also includes cases where the angle is between 85° and 95°. , with an error of up to ±5%.

[0035] In addition, in this specification, when an etching process is performed after a photolithography process, In this case, unless otherwise specified, the resist mask formed in the photolithography process is It shall be removed after the etching process is completed.

[0036] (Embodiment 1) A structural example of a display device 100 of one embodiment of the present invention will be described with reference to the drawings. 1(B) is a top view of the display device 100, and FIG. 1(B) is a view of the display device 100 along the dashed line A1-A2 in FIG. 1(A). 1(C) is a cross-sectional view of the portion indicated by the dashed line B1-B2 in FIG. FIG.

[0037] Although a cross-sectional view is shown in FIG. 1C, one aspect of the embodiment of the present invention is not limited to this. For example, the cross-sectional structure shown in FIG. 24(A) to (F) may be used. As shown in C)(F), the external electrodes 124 are covered with a substrate 147 to protect the connection portions. In addition, in FIGS. 24(D) to 24(F), the semiconductor chip 910 is a COG. As shown in Figures 24(E) and 24(F), In addition, by covering the semiconductor chip 910 with the substrate 147, the semiconductor chip 910 and its connections can be easily This can protect the part.

[0038] 2A to 2C are cross-sectional views illustrating the display device 100 in a bent state. 2(A) to 2(C) show the part indicated by the dashed line B1-B2 in FIG. FIG. 2(A) illustrates a state in which the display device 100 is folded in half. FIG. 2(B) illustrates the display device 100 folded in three. FIG. 2(C) illustrates the display device 100 in a rolled state. Figure 2(C) shows an example of bending in the direction indicated by the dashed line B1-B2 in Figure 1(A). The display device 100 according to one embodiment of the present invention can be bent in any direction. It is possible.

[0039] 3A is a perspective view of the display device 100, and FIG. 3B is a perspective view of the display device 100 shown in FIG. 3A. 1-X2 is a cross-sectional view for explaining in more detail the portion indicated by the dashed line. The figure is not limited to the structure shown in FIG. 3(B), but may also be a structure shown in FIG.

[0040] <Example of display device configuration> The display device 100 shown in this embodiment includes a display region 131, a driving circuit 132, and a driving circuit The display device 100 also includes an electrode 115, an EL layer 117, and an electrode 118. The light emitting element 125 includes a terminal electrode 216. The light emitting element 125 is Each light emitting element 125 is provided with a light emitting element for controlling the amount of light emitted by the light emitting element 125. A transistor 232 is connected to the output of the power supply 232.

[0041] The terminal electrode 216 is electrically connected to the external electrode 124 via the anisotropic conductive connection layer 123. The terminal electrode 216 is electrically connected to the drive circuit 132 and the drive circuit 133. It has been done.

[0042] The driving circuit 132 and the driving circuit 133 are configured by a plurality of transistors 252. The driving circuit 132 and the driving circuit 133 convert the signal supplied from the external electrode 124 into a display. The control circuit 134 has a function of determining which light emitting element 125 in the display area 131 is to be supplied with light.

[0043] The transistor 232 and the transistor 252 are formed by a gate electrode 206, a gate insulating layer 20 7, a semiconductor layer 208, a source electrode 209a, and a drain electrode 209b. The wiring 219 is formed in the same layer as the source electrode 209a and the drain electrode 209b. In addition, an insulating layer 210 is formed over the transistor 232 and the transistor 252. An insulating layer 211 is formed on the insulating layer 210. An electrode 115 is formed on the insulating layer 211. The electrode 115 is formed through an opening formed in the insulating layer 210 and the insulating layer 211. The electrode 115 is electrically connected to the drain electrode 209b. An EL layer 117 and an electrode 118 are formed on the electrode 115 and the partition wall 114. are.

[0044] In addition, the display device 100 has a substrate 111 and a substrate 121 bonded together via an adhesive layer 120. In addition, a substrate 137 is formed on one surface of the substrate 111 via an adhesive layer 138. In addition, a substrate 147 is formed on one surface of the substrate 121 via an adhesive layer 148. It has been done.

[0045] An insulating layer 205 is formed on the other surface of the substrate 111 via an adhesive layer 112. The insulating layer 205 is made of silicon oxide, silicon nitride, silicon oxynitride, or silicon nitride oxide. , aluminum oxide, aluminum oxynitride, or aluminum oxynitride, etc., may be formed as a single layer or The insulating layer 205 is preferably formed by sputtering, CVD, or thermal oxidation. The film can be formed by a chemical reaction method, a coating method, a printing method, or the like.

[0046] An insulating layer 145 is formed on the other surface of the substrate 121 via an adhesive layer 142. A light-shielding layer 264 is formed on the other surface of the substrate 121 via an insulating layer 145. A coloring layer 266 and an overcoat layer 268 are formed via the border layer 145 .

[0047] The insulating layer 205 functions as a base layer, and prevents the transistor from being separated from the substrate 111, adhesive layer 112, etc. This can prevent or reduce the diffusion of moisture and impurity elements into the transistor and light emitting element. In addition, the insulating layer 145 functions as a base layer, and prevents the transistor from being exposed to the substrate 121, adhesive layer 142, etc. This can prevent or reduce the diffusion of moisture and impurity elements into the photoresist and light-emitting element. Layer 145 can be formed using the same materials and methods as insulating layer 205 .

[0048] The substrates 111 and 121 are made of flexible materials such as organic resin materials. The display device 100 can be configured as a so-called bottom emission structure. In the case of a dual emission display device, the EL layer 117 is formed on the substrate 111. A material that is transparent to light emitted is used. In the case of a dual emission display device, the substrate 121 is provided with a light emitting layer 117. A material that is translucent to the light is used.

[0049] Similarly, the display device 100 may be a display device with a so-called bottom emission structure (bottom emission structure), or In the case of a dual emission type display device, the substrate 137 is provided with a layer for emitting light from the EL layer 117. In addition, the display device 100 is a top emission type display device, or In the case of a dual emission type display device, the substrate 147 is provided with a transparent layer for the light emitted from the EL layer 117. A material having optical properties is used.

[0050] Furthermore, if the mechanical strength of the materials used for the substrates 111 and 121 is too low, the display Since the substrate is easily deformed during the manufacturing of the device 100, the yield and other productivity problems may occur. On the other hand, the materials used for the substrates 111 and 121 have high mechanical strength. If the bending strength is too high, the display device will be difficult to bend. The Young's modulus of the material suitable for the substrate 111 and the substrate 121 is 1 GPa ( 1×10 9Pa) or more than 100GPa (100×10 9 Pa) or less, preferably 2GPa or less The Young's modulus is preferably 50 GPa or less, more preferably 2 GPa or more and 20 GPa or less. Measurements are based on ISO527, JISK7161, JISK7162, JISK7127, A This can be done with reference to STMD638, ASTM D882, etc.

[0051] The thickness of the substrate 111 and the substrate 121 is preferably 5 μm or more and 100 μm or less, and more preferably 10 μm or less. More preferably, the thickness of the substrate 111 or the substrate 121 is 50 μm or less. Both may be laminated substrates having multiple layers.

[0052] It is preferable that the substrate 111 and the substrate 121 are made of the same material and have the same thickness. However, depending on the purpose, different materials or different thicknesses may be used.

[0053] The substrate 111 and the substrate 121 may be made of a flexible material having a transparency to visible light. Examples of materials having this property include polyethylene terephthalate resin and polyethylene naphthalate. resin, polyacrylonitrile resin, polyimide resin, polymethyl methacrylate resin, Polycarbonate resin, polyethersulfone resin, polyamide resin, cycloolefin Examples include polyethylene resin, polystyrene resin, polyamide-imide resin, and polyvinyl chloride resin. If it is not necessary to transmit light, a non-transparent substrate may be used. Plate 121 or substrate 111 may be made of aluminum or the like.

[0054] The thermal expansion coefficient of the substrate 121 and the substrate 111 is preferably 30 ppm / K or less, and more preferably 10 ppm / K or less. More preferably, the concentration is 10 ppm / K or less. In advance, a film containing nitrogen and silicon such as silicon nitride or silicon nitride oxide, or a film containing aluminum nitride or the like is prepared. A protective film with low water permeability, such as a film containing nitrogen and aluminum, may be formed. The substrate 121 and the substrate 111 are structures in which a fibrous body is impregnated with an organic resin (so-called plastics). (also called repreg) may also be used.

[0055] By using such a substrate, it is possible to provide a display device that is less likely to break. This can provide a lightweight display device, or a display device that is easy to bend. It is possible.

[0056] The substrate 137 is made of a material softer than the substrate 111. For example, The substrate 147 is made of a material having a smaller Young's modulus than the substrate 111. For example, the substrate 147 may be made of a material having a Young's modulus lower than that of the substrate 121. Use materials with low

[0057] The Young's modulus of the material used for the substrate 137 is 1 / 50 of the Young's modulus of the material used for the substrate 111 Preferably, 1 / 100 or less is more preferable, and 1 / 500 or less is even more preferable. The Young's modulus of the material used for the substrate 147 is 5 times that of the material used for the substrate 121. Preferably, it is 1 / 0 or less, more preferably 1 / 100 or less, and even more preferably 1 / 500 or less. preferable.

[0058] An example of a material that can be used for the substrate 137 and the substrate 147 is silicone rubber. Fluorine rubber and other polymeric materials having viscoelasticity are also used. The material used for the substrate 137 and the substrate 138 is preferably a light-transmitting material. The substrates 147 may be made of the same material or different materials.

[0059] In addition, the substrates 137 and 147 are bonded together with the substrates 111 and 121 sandwiched therebetween. In this case, it is preferable that the thicknesses of the substrates 137 and 147 are equal. By making the thickness of the substrate 111 and the substrate 147 equal, the substrate 111 and the substrate 121 can be easily formed in the bent portion. Therefore, the stress applied to the substrate 111 and the substrate 121 during bending can be reduced. This can reduce the stress that occurs.

[0060] In addition, materials with a small Young's modulus are more likely to deform than materials with a large Young's modulus, so Therefore, the substrate 137 and the substrate 147 are preferably made of the same material as the substrate 11. By using a material having a smaller Young's modulus than the substrate 111 and the substrate 121, and relieves localized stress occurring in the substrate 111 and the substrate 121, thereby preventing damage to the substrate 111 and the substrate 121. Furthermore, the substrates 137 and 147 are resistant to external physical pressure and shock. It also functions as a buffer to disperse

[0061] In addition, by having the substrate 137 or the substrate 147 on the inside of the bent portion, the curvature of the inside of the bent portion can be reduced. This prevents the radius from becoming smaller than the thickness of the substrate 137 or the substrate 147. Therefore, the bending of the substrate 111 or the substrate 121 with an excessively small radius of curvature may cause Damage can be prevented.

[0062] According to one aspect of the present invention, when the display device 100 is bent, the radius of curvature of the inner side of the bent portion is 1 Even if the distance is less than 1 mm, damage to the display device 100 can be prevented.

[0063] The thickness of the substrate 137 is preferably 2 times or more and 100 times or less than that of the substrate 111, and more preferably 5 times or more and 50 times or less. The thickness of the substrate 147 is preferably 2 to 100 times that of the substrate 121. The thickness of the substrate 137 is preferably 5 times or more and 50 times or less. In addition, by making the substrate 147 thicker than the substrate 121, the effect of stress relaxation and buffering can be achieved. can be made good.

[0064] It is preferable that the substrate 137 and the substrate 147 are made of the same material and have the same thickness. However, depending on the purpose, different materials or different thicknesses may be used.

[0065] Depending on the application of the display device, either the substrate 137 or the substrate 147 may be used. Alternatively, one or both of the substrate 137 and the substrate 147 may be provided. may be a laminated substrate having multiple layers.

[0066] According to one aspect of the present invention, a display device that is resistant to external impact and is not easily damaged can be realized. can be done.

[0067] According to one aspect of the present invention, a highly reliable and durable device is provided that is resistant to breakage even when repeatedly bent and extended. A display device can be realized.

[0068] <Pixel circuit configuration example> Next, a more specific example of the configuration of the display device 100 will be described with reference to FIG. 1 is a block diagram for explaining the configuration of a display device 100. The display area 131, the driving circuit 132, and the driving circuit 133 are shown. For example, the driver circuit 133 functions as a scanning line driver circuit. It functions as such.

[0069] The display devices 100 are arranged substantially parallel to one another and are driven by a driving circuit 132. The m scanning lines 135 are arranged substantially parallel to each other and are controlled by the driving circuit 133. The display area 131 has n signal lines 136 whose potentials are controlled by the signal lines 136. The pixel 134 is arranged in a trix shape. The circuit 133 may be collectively referred to as a drive circuit section.

[0070] Each scanning line 135 is connected to one of the pixels 134 arranged in m rows and n columns in the display area 131. The signal lines 136 are electrically connected to the n pixels 134 arranged in any row. is m pixels 134 arranged in any one of the columns among the pixels 134 arranged in m rows and n columns. 4. Both m and n are integers of 1 or greater.

[0071] 4B and 4C show a pixel 134 of the display device shown in FIG. 4A. The circuit configuration shown is as follows:

[0072] [Example of a pixel circuit for a light-emitting display device] The pixel 134 shown in FIG. 4B includes a transistor 431, a capacitor 233, and a transistor The light-emitting element 125 includes a transistor 232 and a light-emitting element 125 .

[0073] One of the source electrode and the drain electrode of the transistor 431 is connected to a transistor Further, the transistor 431 is electrically connected to a line (hereinafter referred to as a signal line DL_n). The gate electrode is electrically connected to the wiring (hereinafter referred to as the scanning line GL_m) to which the gate signal is given. is connected to.

[0074] The transistor 431 is turned on or off to connect the node of the data signal 435.

[0075] One of a pair of electrodes of the capacitor 233 is electrically connected to the node 435, and the other is The source electrode and the drain electrode of the transistor 431 are electrically connected to the gate 437. The other of the electrodes is electrically connected to node 435 .

[0076] The capacitor 233 functions as a storage capacitor that stores data written to the node 435. It has.

[0077] One of the source electrode and the drain electrode of the transistor 232 is electrically connected to the potential supply line VL_a. The other end is electrically connected to node 437. The gate electrode of is electrically connected to node 435.

[0078] One of the anode and the cathode of the light emitting element 125 is electrically connected to the potential supply line VL_b. and the other is electrically connected to node 437.

[0079] The light emitting element 125 may be, for example, an organic electroluminescence element (also called an organic EL element). However, the light emitting element 125 is not limited to this, and An inorganic EL element made of an inorganic material may also be used.

[0080] A high power supply potential VDD is applied to one of the potential supply lines VL_a and VL_b. and the other is supplied with a low power supply potential VSS.

[0081] In the display device having the pixels 134 of FIG. 4B, the first driver circuit 132 drives the pixels of each row. 134 is selected in turn, and transistor 431 is turned on to apply the data signal to node 435. Write.

[0082] In the pixel 134 in which data is written to the node 435, the transistor 431 is turned off. Furthermore, the transistor 435 is turned on in response to the potential of the data written to the node 435. The amount of current flowing between the source electrode and the drain electrode of the transistor 232 is controlled, and the light emitting element 125 emits light at a brightness that corresponds to the amount of current flowing. You can display the image.

[0083] [An example of a pixel circuit for a liquid crystal display device] The pixel 134 shown in FIG. 4C includes a liquid crystal element 432, a transistor 431, and a capacitor 2. 33 and has.

[0084] The potential of one of the pair of electrodes of the liquid crystal element 432 is set appropriately according to the specifications of the pixel 134. The alignment state of the liquid crystal element 432 is determined by data written to the node 436 . Note that one of the pair of electrodes of the liquid crystal element 432 included in each of the plurality of pixels 134 is connected to a common In addition, a potential (common potential) may be applied to one of the liquid crystal elements 432 for each pixel 134 in each row. A different potential may be applied to one of the pair of electrodes.

[0085] For example, the display device including the liquid crystal element 432 can be driven in TN mode, STN mode, or the like. Mode, VA mode, ASM (Axially Symmetric Aligned Mix cro-cell mode, OCB (Optically Compensated B refrigeration mode, FLC (Ferroelectric Liquid d Crystal) mode, AFLC (AntiFerroelectric Liq. Crystal) mode, MVA mode, PVA (Patterned Ver Artificial Alignment mode, IPS mode, FFS mode, or TBA (Transverse Bend Alignment) mode may also be used. In addition to the above-mentioned driving method, the display device can also be driven by an ECB (Electric Carrier Board) or the like. Ally Controlled Birefringence mode, PDLC (P Polymer Dispersed Liquid Crystal (PNLC) mode (Polymer Network Liquid Crystal) mode, guest However, there are various types of liquid crystal elements and their driving methods, and they are not limited to these. A variety of materials can be used.

[0086] In addition, a liquid crystal composition containing a liquid crystal exhibiting a blue phase and a chiral agent The liquid crystal element 432 may be configured as follows. The liquid crystal that exhibits the blue phase does not require alignment treatment. Furthermore, the response time of the liquid crystal that shows the blue phase is short, at 1 msec or less, and it is optically Because it is isotropic, it has little viewing angle dependency.

[0087] As the display element, a display element other than the light emitting element 125 and the liquid crystal element 432 is used. For example, electrophoretic elements, electronic inks, and electrophoretic display elements can be used as display elements. Wetting elements, MEMS (microelectromechanical systems), digital Micromirror Device (DMD), DMS (Digital Micro Shutter), M IRASOL®, an IMOD (Interference Modulation) element It is also possible to use the following.

[0088] In the pixel 134 in the mth row and the nth column, the source electrode and the drain electrode of the transistor 431 One is electrically connected to the signal line DL_n, and the other is electrically connected to the node 436. The gate electrode of the transistor 431 is electrically connected to the scanning line GL_m. By being in an on or off state, the data signal to node 436 is transmitted. It has the function of controlling the writing of

[0089] One of the pair of electrodes of the capacitor 233 is connected to a wiring to which a specific potential is supplied (hereinafter, referred to as a capacitor line CL ) and the other is electrically connected to node 436. The other of the pair of electrodes of 32 is electrically connected to a node 436. The value of is set appropriately according to the specifications of the pixel 134. The capacitance element 233 is connected to the node 436. It functions as a storage capacitor that stores written data.

[0090] For example, in a display device having the pixel 134 shown in FIG. 4C, the first driver circuit 132 drives each pixel. The pixels 134 in the row are selected in sequence, and transistor 431 is turned on to supply data to node 436. Write the data signal.

[0091] In the pixel 134 in which the data signal is written to the node 436, the transistor 431 is in the off state. By repeating this for each row, an image can be displayed.

[0092] <Modification> FIG. 5 shows a display device 200 having a different configuration from the display device 100. FIG. 5(A) shows a display device 200 having a different configuration from the display device 100. 5(A) is a top view of the display device 200, and FIG. 5(B) is a view of the display device 200 shown by the dashed line A3-A4 in FIG. 5(C) is a cross-sectional view of the portion indicated by the dashed line B3-B4 in FIG. FIG.

[0093] Although a cross-sectional view is shown in FIG. 5C, one aspect of the embodiment of the present invention is not limited to this. For example, the cross-sectional structure shown in FIG. 26(A) to (H) may be used. As shown in C), (D), (G), and (H), the external electrode 124 is covered with a substrate 147, As shown in Figs. 26(D) and 26(H), the external electrode 12 By covering the substrate 4 with the substrate 147 and the substrate 137, the connection portion can be protected. As shown in FIGS. 26(F), (G), and (H), the semiconductor chip 910 is covered with a substrate 147. This makes it possible to protect the semiconductor chip 910 and its connecting portions.

[0094] The display device 200 is a display device 100 in which at least a part of the substrate 137 and the substrate 147 is The substrate 111 and the substrate 121 extend beyond the edge of the substrate 137 and the substrate 137 at the extending portion. The difference is that the substrate 147 is connected to the display device 100. The other components are formed in the same manner as the display device 100. The substrate 137 and the substrate 147 in the extension portion are bonded to each other via an adhesive layer or the like. The connection may be indirect or direct.

[0095] By adopting a configuration such as that of the display device 200, impurities from the ends of the substrate 111 and the substrate 121 can be prevented. Since it becomes difficult for objects to enter, the reliability of the display device can be further improved.

[0096] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0097] (Embodiment 2) In this embodiment, an example of a manufacturing method of the display device 100 will be described with reference to FIGS. 6 to 12 show the area indicated by the dashed line X1-X2 in FIG. It corresponds to a cross section.

[0098] <Example of a method for manufacturing a display device> [Forming a release layer] First, a release layer 113 is formed on an element formation substrate 101 (see FIG. 6(A)). The substrate 101 may be a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, A metal substrate or the like can be used. A plastic substrate having such a structure may also be used.

[0099] The glass substrate may be made of, for example, aluminosilicate glass or aluminoborosilicate glass. Glass materials such as barium borosilicate glass are used. By adding more BaO, a more practical heat-resistant glass can be obtained. Russ etc. can be used.

[0100] The release layer 113 may be made of tungsten, molybdenum, titanium, tantalum, niobium, nickel, or copper. Baltic, Zirconium, Ruthenium, Rhodium, Palladium, Osmium, Iridium, An element selected from silicon, or an alloy material containing the element, or a chemical compound containing the element The insulating film can be formed by using a composite material. The crystalline structure of the separation layer 113 may be amorphous, microcrystalline, or polycrystalline. The peeling layer 113 may be formed of aluminum oxide, gallium oxide, zinc oxide, or Titanium oxide, indium oxide, indium tin oxide, indium zinc oxide, or In It can also be formed using a metal oxide such as GaZnO (IGZO).

[0101] The peeling layer 113 can be formed by a sputtering method, a CVD method, a coating method, a printing method, or the like. The coating method includes a spin coating method, a droplet ejection method, and a dispense method.

[0102] When the peeling layer 113 is formed as a single layer, it is preferably made of tungsten, molybdenum, or a combination of tungsten and molybdenum. It is preferable to use an alloy material containing molybdenum. Alternatively, the peeling layer 113 may be formed as a single layer. In this case, tungsten oxide or oxynitride, molybdenum oxide or oxide Nitrides, or oxides or oxynitrides of alloys containing tungsten and molybdenum It is preferable that

[0103] The peeling layer 113 may be a layer containing tungsten and a layer containing an oxide of tungsten. When a stacked structure of layers containing tungsten is formed, an oxide insulating layer is formed in contact with the layer containing tungsten. As a result, tungsten oxide is formed at the interface between the tungsten-containing layer and the oxide insulating layer. Alternatively, the surface of the layer containing tungsten may be subjected to a thermal oxidation treatment, an oxygen plating treatment, or the like. The material is treated with a strong oxidizing solution such as ozonated water or ozone water to remove tungsten oxides. A layer containing the metal may be formed.

[0104] In this embodiment, a glass substrate is used as the element formation substrate 101. As a first step, tungsten is formed on the element formation substrate 101 by sputtering.

[0105] [Forming an insulating layer] Next, an insulating layer 205 is formed as a base layer on the peeling layer 113 (see FIG. 6(A)). The edge layer 205 may be made of silicon oxide, silicon nitride, silicon oxynitride, silicon nitride oxide, or silicon oxide. aluminum nitride, aluminum oxynitride, aluminum nitride oxide, etc., as a single layer or It is preferable to form the insulating layer 205 in a multi-layer structure. For example, the insulating layer 205 may be formed of silicon oxide and silicon nitride. It may be a two-layer structure made by laminating the materials, or a five-layer structure made by combining the above materials. The layer 205 is formed by using a sputtering method, a CVD method, a thermal oxidation method, a coating method, a printing method, or the like. It is possible to do this.

[0106] The thickness of the insulating layer 205 is 30 nm or more and 500 nm or less, preferably 50 nm or more and 400 nm or less. m or less.

[0107] The insulating layer 205 prevents the diffusion of impurity elements from the element formation substrate 101, the peeling layer 113, etc. Furthermore, even after the element formation substrate 101 is replaced with the substrate 111, Preventing the diffusion of impurity elements from the substrate 111 or the adhesive layer 112 into the light emitting element 125, or In this embodiment, the insulating layer 205 is formed by plasma CVD. A laminated film of silicon oxynitride with a thickness of 200 nm and silicon nitride oxide with a thickness of 50 nm is used. .

[0108] [Forming the gate electrode] Next, a gate electrode 206 is formed on the insulating layer 205 (see FIG. 6(A)). Gate electrode 206 is made of aluminum, chromium, copper, tantalum, titanium, molybdenum, and tungsten. or an alloy containing the above metal elements, or It can be formed by using a combination of alloys, etc. Also, manganese, zirconium, etc. The gate electrode 206 may be formed of one or more metal elements selected from the above. The film may have a single layer structure or a laminated structure of two or more layers. a single-layer structure of aluminum film, a two-layer structure of aluminum film laminated on titanium film, a titanium nitride film laminated on titanium film, Two-layer structure with a titanium film laminated on top, two-layer structure with a tungsten film laminated on top of a titanium nitride film, nitride Two-layer structure in which a tungsten film is laminated on a tantalum film or a tungsten nitride film, titanium film A two-layer structure with a copper film laminated on top, a titanium film, and an aluminum film laminated on top of the titanium film. There are also three-layer structures in which a titanium film is formed on top of the aluminum. Elements selected from tantalum, tungsten, molybdenum, chromium, neodymium, and scandium A pure film, an alloy film made by combining a plurality of films, or a nitride film may be used.

[0109] The gate electrode 206 is made of indium tin oxide, indium oxide containing tungsten oxide. oxide, indium zinc oxide with tungsten oxide, indium oxide with titanium oxide Indium tin oxide, indium zinc oxide, silicon oxide containing titanium oxide A light-transmitting conductive material such as indium tin oxide can also be used. A laminated structure of the above-mentioned light-transmitting conductive material and the above-mentioned metal element may also be used.

[0110] First, the gate electrode 20 is formed on the insulating layer 205 by sputtering, CVD, vapor deposition, or the like. A conductive film to be the layer 6 is laminated, and a resist mask is formed on the conductive film by a photolithography process. Next, a part of the conductive film that will become the gate electrode 206 is etched using a resist mask. The gate electrode 206 is formed by etching. At this time, other wirings and electrodes are also formed at the same time. It is possible.

[0111] The etching of the conductive film may be performed by dry etching or wet etching, or both. When dry etching is used, the resist mask may be If an ashing process is performed before removing the resist mask, it becomes easier to remove the resist mask using a stripping solution. It can be said that:

[0112] The gate electrode 206 may be formed by electrolytic plating, printing, inkjet printing, or the like instead of the above-mentioned method. It may also be formed by a jet method or the like.

[0113] The thickness of the gate electrode 206 is 5 nm or more and 500 nm or less, and more preferably 10 nm or more and 300 nm or less. 00 nm or less, and more preferably 10 nm or more and 200 nm or less.

[0114] Furthermore, by forming the gate electrode 206 using a conductive material having a light-shielding property, the gate electrode 206 can be protected from external light. This makes it difficult for the light to reach the semiconductor layer 208 from the gate electrode 206 side. As a result, fluctuations in the electrical characteristics of the transistor due to light irradiation can be suppressed.

[0115] [Forming a gate insulating layer] Next, the gate insulating layer 207 is formed (see FIG. 6(A)). For example, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide aluminum, a mixture of aluminum oxide and silicon oxide, hafnium oxide, gallium oxide or A Ga-Zn-based metal oxide or the like may be used, and the layer may be a laminate or a single layer.

[0116] The gate insulating layer 207 is made of hafnium silicate (HfSiO x ), nitrogen added Hafnium silicate (HfSi x O y N z ), nitrogen-doped hafnium aluminium Laminate (HfAl x O y N z ), hafnium oxide, yttrium oxide, etc. The use of high-k materials can reduce the gate leakage of transistors. A laminate of carbon and hafnium oxide may also be used.

[0117] The thickness of the gate insulating layer 207 is 5 nm or more and 400 nm or less, and more preferably 10 nm or more. It is preferable to set the thickness to 300 nm or less, and more preferably to set the thickness to 50 nm or more and 250 nm or less.

[0118] The gate insulating layer 207 can be formed by a sputtering method, a CVD method, a vapor deposition method, or the like. .

[0119] The gate insulating layer 207 may be a silicon oxide film, a silicon oxynitride film, or a silicon nitride oxide film. When forming a silicon film, a deposition gas containing silicon and an oxidizing gas are used as source gases. Representative examples of silicon-containing deposition gases include silane, disilane, Examples of oxidizing gases include trisilane, fluorinated silane, etc. Examples of oxidizing gases include oxygen, ozone, and nitrous oxide. , nitrogen dioxide, etc.

[0120] The gate insulating layer 207 is made of a nitride insulating layer and an oxide insulating layer in this order from the gate electrode 206 side. By providing a nitride insulating layer on the gate electrode 206 side, From the gate electrode 206 side, hydrogen, nitrogen, alkali metal, alkaline earth metal, etc. It is possible to prevent the migration of nitrogen, alkali metals, or Alkaline earth metals and the like function as impurity elements in semiconductors. It functions as an impurity element of the conductor. Therefore, the term "impurity" in this specification includes hydrogen, This includes nitrogen, alkali metals, alkaline earth metals, and the like.

[0121] When an oxide semiconductor is used as the semiconductor layer 208, an oxide insulating layer is formed on the semiconductor layer 208 side. By providing the edge layer, the defect level density at the interface between the gate insulating layer 207 and the semiconductor layer 208 is As a result, a transistor with little deterioration in electrical characteristics can be obtained. When an oxide semiconductor is used for the semiconductor layer 208, an oxide insulating layer can be formed. In this case, an oxide insulating layer containing more oxygen than the oxygen that satisfies the stoichiometric composition is used. This further reduces the defect level density at the interface between the gate insulating layer 207 and the semiconductor layer 208. This is preferable because it is possible to

[0122] When the gate insulating layer 207 is a stack of a nitride insulating layer and an oxide insulating layer as described above, In this case, the nitride insulating layer is preferably thicker than the oxide insulating layer.

[0123] Since the nitride insulating layer has a larger dielectric constant than the oxide insulating layer, the thickness of the gate insulating layer 207 is Even if the thickness is increased, the electric field generated in the gate electrode 206 can be efficiently transmitted to the semiconductor layer 208. In addition, by making the entire gate insulating layer 207 thick, the dielectric strength of the gate insulating layer 207 can be increased. Therefore, the reliability of the semiconductor device can be improved.

[0124] The gate insulating layer 207 is made of a first nitride insulating layer having few defects and a second nitride insulating layer having hydrogen blocking properties. A second nitride insulating layer having a high resistance and an oxide insulating layer are stacked in this order from the gate electrode 206 side. The gate insulating layer 207 can have a laminated structure in which a first nitride insulating layer having few defects is formed. By using the layer, the breakdown voltage of the gate insulating layer 207 can be improved. When an oxide semiconductor is used as the conductor layer 208, the gate insulating layer 207 is provided with a hydrogen blocking layer. By providing the second nitride insulating layer with high insulating properties, the gate electrode 206 and the first nitride insulating layer The hydrogen contained in the edge layer can be prevented from migrating to the semiconductor layer 208.

[0125] An example of a method for forming the first nitride insulating layer and the second nitride insulating layer will be described below. By using a plasma CVD method with a mixture of orthogonal, nitrogen, and ammonia gas as the source gas, Then, a silicon nitride film with few defects is formed as the first nitride insulating layer. By switching to a mixture of silane and nitrogen, the hydrogen concentration is low and hydrogen is blocked. A silicon nitride film capable of being formed by this method is deposited as the second nitride insulating layer. By this method, a nitride insulating layer having few defects and a hydrogen blocking property is stacked. A gate insulating layer 207 can also be formed.

[0126] The gate insulating layer 207 is made up of a third nitride insulating layer having high impurity blocking properties and a defect-resistant layer. A first nitride insulating layer with few defects, a second nitride insulating layer with high hydrogen blocking properties, and an oxide The gate electrode 206 may have a laminated structure in which a nitride insulating layer and a nitride insulating layer are laminated in this order from the gate electrode 206 side. The gate insulating layer 207 is provided with a third nitride insulating layer having high impurity blocking properties. Then, hydrogen, nitrogen, alkali metal, alkaline earth metal, etc. are introduced from the gate electrode 206 into the semiconductor. This can prevent the material from migrating to the body layer 208.

[0127] An example of a method for forming the first to third nitride insulating layers will be described below. The plasma CVD method was performed using a mixture of silane, nitrogen, and ammonia as the source gas. A silicon nitride film having high impurity blocking properties is formed as the third nitride insulating layer. Next, by increasing the flow rate of ammonia, a silicon nitride film with fewer defects was obtained. Next, the source gas is switched to a mixed gas of silane and nitrogen. The second silicon nitride film has a low hydrogen concentration and is capable of blocking hydrogen. By using this method, the nitride insulating layer can be formed with few defects and no impurities. The gate insulating layer 207 is formed by stacking a nitride insulating layer having blocking properties. can.

[0128] When a gallium oxide film is formed as the gate insulating layer 207, MOCVD (Metal Organic Chemical Vapor Deposition (OCVD) method It can be formed by

[0129] The semiconductor layer 208 in which the channel of the transistor is formed and the insulating layer containing hafnium oxide are The insulating layer is laminated on the insulating layer containing hafnium oxide, and electrons are injected into the insulating layer containing hafnium oxide. This allows the threshold voltage of the transistor to be changed.

[0130] [Forming a semiconductor layer] The semiconductor layer 208 may be formed using an amorphous semiconductor, a microcrystalline semiconductor, a polycrystalline semiconductor, or the like. For example, amorphous silicon or microcrystalline germanium can be used. In addition, compound semiconductors such as silicon carbide, gallium arsenide, oxide semiconductors, and nitride semiconductors, An organic semiconductor or the like can be used.

[0131] When an organic semiconductor is used as the semiconductor layer 208, a low molecular weight organic material having an aromatic ring is used. and π-electron conjugated conductive polymers can be used. For example, rubrene, tetracene, etc. , pentacene, perylenediimide, tetracyanoquinodimethane, polythiophene, polya Cetylene, polyparaphenylene vinylene, etc. can be used.

[0132] When an oxide semiconductor is used for the semiconductor layer 208, CAAC-OS (C Axi s Aligned Crystalline Oxide Semiconductor r), polycrystalline oxide semiconductor, microcrystalline oxide semiconductor, nc-OS (nano Crysta amorphous oxide semiconductor) It is possible.

[0133] Oxide semiconductors have a large energy gap of 3.0 eV or more, and are highly sensitive to visible light. In addition, in transistors obtained by processing oxide semiconductors under appropriate conditions, In this case, the off-state current is 100zA (1×) under the temperature conditions in use (for example, 25°C). 10 -19 A) or less, or 10zA (1 x 10 -20 A) and below, and even 1zA(1 x10 -21 A) or less. Therefore, a display device with low power consumption can be provided. It is possible.

[0134] When an oxide semiconductor is used for the semiconductor layer 208, the insulating layer in contact with the semiconductor layer 208 is It is preferable to use an insulating layer containing oxygen.

[0135] The thickness of the semiconductor layer 208 is 3 nm or more and 200 nm or less, preferably 3 nm or more and 100 nm or less. More preferably, the thickness is 3 nm or more and 50 nm or less. As the oxide semiconductor film 08, a 30-nm-thick oxide semiconductor film is formed by a sputtering method.

[0136] Next, a resist mask is formed over the oxide semiconductor film, and an oxide semiconductor film is formed using the resist mask. A part of the semiconductor film is selectively etched to form a semiconductor layer 208. The mask is formed by photolithography, printing, inkjet printing, or the like. When the resist mask is formed by the inkjet method, it is possible to Therefore, manufacturing costs can be reduced.

[0137] The oxide semiconductor film may be etched by either dry etching or wet etching. After the etching of the oxide semiconductor film is completed, the resist mask is removed. (See Figure 6(B)).

[0138] [Forming source electrodes, drain electrodes, etc.] Next, the source electrode 209a, the drain electrode 209b, the wiring 219, and the terminal electrode 216 First, a conductive film is formed on the gate insulating layer 207 and the semiconductor layer 208 (see FIG. 6(C)). Form a film.

[0139] Conductive films include aluminum, titanium, chromium, nickel, copper, yttrium, and zirconium. elemental metals consisting of tungsten, molybdenum, silver, tantalum, or tungsten, or The alloy mainly composed of silicon can be used in a single layer structure or a laminated structure. a single-layer structure of an aluminum film containing titanium; a two-layer structure of an aluminum film laminated on a titanium film; Two-layer structure with aluminum film laminated on copper-magnesium-aluminum film Two-layer structure with copper film laminated on alloy film, two-layer structure with copper film laminated on titanium film, tungsten A two-layer structure in which a copper film is laminated on a titanium film or titanium nitride film, and the titanium film or An aluminum film or copper film is laminated on the titanium nitride film, and then a titanium film or copper film is laminated on top of that. a three-layer structure in which a molybdenum film or a titanium nitride film is formed, a molybdenum film or a molybdenum nitride film, and the molybdenum film or the molybdenum nitride film. An aluminum film or a copper film is laminated on the molybdenum film or the molybdenum nitride film, and further A three-layer structure in which a molybdenum film or a molybdenum nitride film is formed on the tungsten film. There is also a three-layer structure in which a copper film is laminated on top of the tungsten film.

[0140] In addition, indium tin oxide, zinc oxide, indium oxide containing tungsten oxide, acid Indium zinc oxide containing tungsten oxide, indium oxide containing titanium oxide, Indium tin oxide containing titanium, indium zinc oxide, indium with silicon oxide Conductive materials containing oxygen, such as aluminum tin oxide, and those containing nitrogen, such as titanium nitride and tantalum nitride. A conductive material may be used. In addition, a material containing the above-mentioned metal element and a conductive material containing oxygen may be used. It is also possible to use a laminated structure in which the above-mentioned material containing a metal element and It is also possible to use a laminated structure in which a conductive material containing nitrogen is combined. A product of a combination of a material containing an element, a conductive material containing oxygen, and a conductive material containing nitrogen It can also be a layered structure.

[0141] The thickness of the conductive film is preferably 5 nm or more and 500 nm or less, more preferably 10 nm or more and 300 nm or less. nm or less, and more preferably 10 nm or more and 200 nm or less. A tungsten film having a thickness of 300 nm is formed.

[0142] Next, a portion of the conductive film is selectively etched using a resist mask to form a source electrode 20 9a, the drain electrode 209b, the wiring 219, and the terminal electrode 216 (formed from the same film as this The resist mask is formed by photolithography. The resist mask can be formed by a suitable method such as a drawing method, a printing method, or an ink-jet method. When the inkjet method is used to form the film, no photomask is required, which reduces manufacturing costs. do.

[0143] The etching of the conductive film may be performed by dry etching or wet etching, or both. It should be noted that the etching step removes a part of the exposed semiconductor layer 208. After etching of the conductive film is completed, the resist mask is removed.

[0144] [Forming an insulating layer] Next, the source electrode 209a, the drain electrode 209b, the wiring 219, and the terminal electrode 216 An insulating layer 210 is formed on the insulating layer 205 (see FIG. 6(D)). It can be formed using similar materials and methods.

[0145] In addition, when an oxide semiconductor is used for the semiconductor layer 208, at least the semiconductor of the insulating layer 210 It is preferable to use an insulating layer containing oxygen in the region in contact with the layer 208. For example, the insulating layer 2 When the insulating film 10 is a multi-layer laminate, at least the layer in contact with the semiconductor layer 208 is made of silicon oxide. It is sufficient to form it.

[0146] [Formation of openings] Next, a portion of the insulating layer 210 is selectively etched using a resist mask to form an opening 12. 8 is formed (see FIG. 6(D)). At this time, other openings (not shown) are also formed at the same time. The resist mask is formed by photolithography, printing, inkjet printing, etc. If the resist mask is formed by the inkjet method, it is possible to use a photomask. Since no external wiring is used, manufacturing costs can be reduced.

[0147] The etching of the insulating layer 210 may be performed by dry etching or wet etching. Both may be used.

[0148] By forming the opening 128, the drain electrode 209b and a part of the terminal electrode 216 are exposed. After the opening 128 is formed, the resist mask is removed.

[0149] [Forming a planarizing film] Next, an insulating layer 211 is formed on the insulating layer 210 (see FIG. 7(A)). , can be formed using the same material and method as the insulating layer 205.

[0150] In order to reduce the surface irregularities on the surface on which the light emitting element 125 is formed, the insulating layer 211 is subjected to a planarization treatment. The planarization process is not particularly limited, but may be a polishing process (for example, a chemical mechanical polishing process). Polishing method (Chemical Mechanical Polishing: CMP), This can be done by dry etching or etching.

[0151] In addition, by forming the insulating layer 211 using an insulating material having a planarizing function, the polishing process can be performed. The insulating material having a planarizing function may be, for example, a polyimide resin, Organic materials such as acrylic resins can be used. In addition to the above organic materials, low dielectric constant materials can also be used. In addition, insulating layers formed from these materials can be used. The insulating layer 211 may be formed by stacking a plurality of layers.

[0152] Also, a part of the insulating layer 211 in the region overlapping the opening 128 is removed to form an opening 129. At this time, other openings (not shown) are also formed at the same time. The insulating layer 211 in the area where the openings 129 are to be formed is removed. A resist mask is formed by a lithography process, and the insulating layer 211 is covered with the resist mask. By forming an opening 129, the unetched area can be etched away. , exposing the surface of the drain electrode 209b.

[0153] In addition, by using a photosensitive material for the insulating layer 211, it is possible to use a resist mask. In this embodiment, the opening 129 can be formed without using a photosensitive polyimide resin. This is used to form the insulating layer 211 and the opening 129 .

[0154] [Forming the anode] Next, the electrode 115 is formed over the insulating layer 211 (see FIG. 7B). The EL layer 117 is formed using a conductive material that efficiently reflects the light emitted by the EL layer 117. It is preferable that the electrode 115 is not limited to a single layer, but may have a multi-layer structure. For example, when the electrode 115 is used as an anode, the layer in contact with the EL layer 117 is made of indium tin oxide. The layer has a work function larger than that of the EL layer 117 of the material and has light-transmitting properties, and the layer is in contact with the reflective layer. A layer with high refractive index (aluminum, an alloy containing aluminum, or silver, etc.) may be provided. .

[0155] In this embodiment, a display device having a top emission structure is exemplified. Bottom emission structure (bottom injection structure) or dual emission structure (double injection structure) ) display device.

[0156] The display device 100 may be configured as a bottom emission structure (bottom emission structure) or a dual emission structure. In the case of a display device having a dual emission structure, the electrode 115 is made of a conductive material having light transmitting properties. Just use the materials.

[0157] The electrode 115 is formed by forming a conductive film to be the electrode 115 on the insulating layer 211 and then forming a resist on the conductive film. A resist mask is formed on the conductive film, and the region not covered with the resist mask is etched. The conductive film can be formed by etching using a dry etching method or a wet etching method. The resist mask is then formed on the substrate. This can be done by photolithography, printing, inkjet printing, etc. When a resist mask is formed by the inkjet method, a photomask is not used, so the manufacturing After the electrode 115 is formed, the resist mask is removed.

[0158] [Forming a partition] Next, the partition wall 114 is formed (see FIG. 7(C)). The partition wall 114 is formed to separate the light emitting portions of adjacent pixels. This is provided to prevent the element 125 from accidentally shorting out electrically and emitting light erroneously. When a metal mask is used to form the EL layer 117, the metal mask may contact the electrode 115. The partition wall 114 is made of epoxy resin, acrylic resin, imide resin, or the like. The partition wall 1 can be formed of an organic resin material such as grease or an inorganic material such as silicon oxide. 14 is formed so that the side wall is an inclined surface formed with a tapered or continuous curvature. By forming the side wall of the partition wall 114 in such a shape, it is possible to prevent the side wall from being damaged by the later-formed partition wall. This can improve the coverage of the EL layer 117 and the electrode 118 that are to be applied.

[0159] [Forming the EL layer] The configuration of the EL layer 117 will be described in the sixth embodiment.

[0160] [Forming the cathode] In this embodiment, the electrode 118 is used as a cathode, and therefore the electrode 118 is connected to the EL layer 11 (described later). It is preferable to form the electrode 7 using a material with a small work function that can inject electrons. Instead of a metal with a low work function, an alkali metal or alkaline earth metal with a low work function is used. A layer of metal formed several nanometers is formed as a buffer layer, and then a metal material such as aluminum is formed on top of it. The insulating film is formed using a conductive oxide material such as indium tin oxide or a semiconductor material. The buffer layer may be made of an oxide, halide, or magnesium of an alkaline earth metal. An alloy such as neodymium-silver can also be used.

[0161] In addition, when light emitted from the EL layer 117 is extracted through the electrode 118, the electrode 118 is The electrode 115, the EL layer 117, and the electrode 118 preferably have a property of transmitting visible light. As a result, the light emitting element 125 is formed (see FIG. 7(D)).

[0162] [Forming the opposing element formation substrate] The light-shielding layer 264, the coloring layer 266, the overcoat layer 268, the insulating layer 145, and the release layer 1 The element forming substrate 141 on which the element forming layer 43 is formed is placed on the element forming substrate 101 via the adhesive layer 120. (See FIG. 8(A)). The element formation substrate 141 faces the element formation substrate 101. Since the element forming substrate 141 is formed to face each other, it is sometimes called the "opposing element forming substrate." The configuration of the element forming substrate 141 (opposing element forming substrate) will be explained later.

[0163] The element forming substrate 141 is fixed onto the element forming substrate 101 by an adhesive layer 120. The layer 120 may be a photo-curable adhesive, a reaction-curable adhesive, a heat-curable adhesive, or an anaerobic adhesive. For example, epoxy resin, acrylic resin, imide resin, etc. can be used. In the case of a top emission structure, a large amount of light less than the wavelength of light is applied to the adhesive layer 120. Desiccants with a large refractive index (such as zeolite) and fillers with a large refractive index (such as titanium oxide and zirconium Mixing a fluorine-containing compound (e.g., fluorine) is preferable because it improves the extraction efficiency of light emitted by the EL layer 117. .

[0164] [Peeling the element formation substrate from the insulating layer] Next, the element forming substrate 101 that is in contact with the insulating layer 205 via the release layer 113 is removed from the insulating layer 205. The peeling method involves applying mechanical force (human force). peeling by hand or with a jig, separating by rotating a roller, ultrasonic, etc. For example, the peeling layer 113 may be cut with a sharp blade or by laser light irradiation. Put the slit in the slit and pour water into it. Or spray mist of water on the slit. Water seeps into the gap between the release layer 113 and the insulating layer 205 due to capillary action, forming an element shape. The grown substrate 101 can be easily peeled off from the insulating layer 205 .

[0165] [Bonding the substrates together] Next, the substrate 111 is bonded to the insulating layer 205 via the adhesive layer 112 (FIG. 9(A), FIG. 9(B). The adhesive layer 112 can be made of the same material as the adhesive layer 120. In this embodiment, the substrate 111 is made of aramid ( Polyamide resin) is used.

[0166] [Peeling the opposing element formation substrate from the insulating layer] Next, the element forming substrate 141 that is in contact with the insulating layer 145 via the release layer 143 is removed from the insulating layer 145. The element formation substrate 141 is peeled off from the above-mentioned element formation substrate (see FIG. 10(A)). This can be done in the same manner as in peeling off the substrate 101.

[0167] [Bonding the substrates together] Next, the substrate 121 is bonded to the insulating layer 145 via the adhesive layer 142 (see FIG. 10(B)). The adhesive layer 142 can be made of the same material as the adhesive layer 120. The material for 121 can be the same as that for the substrate 111 .

[0168] [Forming an opening] Next, the substrate 121, the adhesive layer 142, and the like in the area overlapping the terminal electrode 216 and the opening 128 are The insulating layer 145, the coloring layer 266, the overcoat layer 268, and the adhesive layer 120 are removed. 11(A) , an opening 122 is formed (see FIG. 11(A)). A portion of the surface of the terminal electrode 216 is exposed.

[0169] [Forming external electrodes] Next, an anisotropic conductive connection layer 123 is formed in the opening 122, and a surface An external electrode 124 is formed to input power and signals to the display device 100 (see FIG. 11(B)). The terminal electrode 216 is electrically connected to the external electrode 124 via the anisotropic conductive connection layer 123. The external electrode 124 is, for example, an FPC (Flexible Printed Circuit). ted circuit) can be used.

[0170] The anisotropic conductive connection layer 123 may be made of various anisotropic conductive films (ACFs). Conductive Film) and Anisotropic Conductive Paste (ACP) It can be formed using a tungsten carbide (Tropical Conductive Paste) or the like.

[0171] The anisotropic conductive connection layer 123 is made of a thermosetting resin or a thermosetting and photosetting resin containing conductive particles. The anisotropic conductive connection layer is made by hardening a paste or sheet-like material that has been mixed. The anisotropic conductive connection layer 123 becomes a material that exhibits anisotropic conductivity when irradiated with light or subjected to thermocompression bonding. The conductive particles used in 123 are, for example, spherical organic resin particles coated with Au, Ni, Co, etc. Particles coated with a thin film of metal can be used.

[0172] [Bonding the substrates together] Next, the substrate 137 is bonded to the substrate 111 via the adhesive layer 138. 7 is attached to the substrate 121 via the adhesive layer 148 (see FIG. 12). The adhesive layer 148 can be made of the same material as the adhesive layer 120. In this embodiment, the substrate 137 and the substrate 147 are made of a 2 mm thick film that is transparent to visible light. Silicone rubber with a thickness of 0.00 μm and a Young's modulus of 0.03 GPa is used.

[0173] [Structures formed on the opposing element formation substrate] Next, regarding the structures such as the light-shielding layer 264 formed on the element formation substrate 141, the following will be described with reference to FIG. and explain.

[0174] First, an element formation substrate 141 is prepared. Next, a release layer 143 and an insulating layer 144 are formed on the element formation substrate 141. The peeling layer 143 is made of the same material as the peeling layer 113 (see FIG. 13(A)). The insulating layer 145 can be formed using the same material and method as the insulating layer 205. It can be formed by the materials and methods.

[0175] Next, a light-shielding layer 264 is formed on the insulating layer 145 (see FIG. 13(B)). A layer 266 is formed (see FIG. 13(C)).

[0176] The light-shielding layer 264 and the colored layer 266 can be formed using various materials by a printing method, an ink-jet method, They are formed at desired positions using photolithography.

[0177] Next, an overcoat layer 268 is formed on the light-shielding layer 264 and the colored layer 266 (FIG. 13 (See (D)).

[0178] The overcoat layer 268 may be made of, for example, acrylic resin, epoxy resin, polyimide, or the like. An organic insulating layer can be used. By forming the overcoat layer 268, e.g. For example, it is possible to prevent impurities contained in the colored layer 266 from diffusing toward the light emitting element 125. However, the overcoat layer 268 does not necessarily have to be provided. A structure in which the overcoat layer 268 is not formed may also be used.

[0179] Alternatively, a light-transmitting conductive film may be formed as the overcoat layer 268. By providing a light-transmitting conductive film as the coating layer 268, the light emitted from the light-emitting element 125 can be The ionized light 235 can be transmitted through the filter, while the ionized impurities can be prevented from being transmitted through the filter.

[0180] The light-transmitting conductive film is made of, for example, indium oxide or indium tin oxide (ITO). Indium Tin Oxide, Indium Zinc Oxide, Zinc Oxide, Gallium Doped In addition to graphene, a light-transmitting material such as zinc oxide can be used. Alternatively, a metal film formed thin enough to be thin enough to be usable may be used.

[0181] Through the above steps, structures such as the light-shielding layer 264 can be formed on the element formation substrate 141.

[0182] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0183] (Embodiment 3) The configuration of the display device 100 having a top emission structure is modified to have a bottom emission structure. A display device 150 can be fabricated.

[0184] <Bottom-emission display device> 14 shows an example of a cross-sectional configuration of a display device 150 with a bottom emission structure. 3A, which is a perspective view of the display device 100, and the area indicated by the dashed line X1-X2 in FIG. The display device 150 of the bottom emission structure has a light-shielding layer 264 The positions of the color layer 266 and the overcoat layer 268 are different from those of the display device 100. Specifically, the display device 150 includes a light-shielding layer 264, a colored layer 266, and an overcoat. A conductive layer 268 is formed on the substrate 111 .

[0185] In the display device 150, the insulating layer 145 is formed directly on the substrate 121, and the adhesive layer 120 is That is, the insulating layer 145 can be attached to the substrate 111 via the element forming substrate 1. Since there is no need to transfer the element formation substrate 141, the peeling layer 143, and the adhesive layer 142, Therefore, the productivity and yield of the display device can be improved. The other components of the display device 150 can be formed in the same manner as the display device 100. do.

[0186] In addition, the display device 150 having the bottom emission structure has the electrode 115 made of a light-transmitting conductive material. The electrode 118 is formed using a conductive material that efficiently reflects the light emitted by the EL layer 117. It is formed using an electrically conductive material.

[0187] The display device 150 transmits light 235 emitted from the EL layer 117 to the substrate via the colored layer 266. It can be launched from the 111 side.

[0188] <Back gate electrode> In the display device 150, the transistors constituting the driving circuit 133 are The transistor 272 is similar to the transistor 252. However, the electrode 263 can be formed in the region on the insulating layer 210 that overlaps with the semiconductor layer 208. The electrode 263 is formed by the same material and method as the gate electrode 206. It can be achieved.

[0189] The electrode 263 can function as a gate electrode. When either the electrode 261 or the electrode 262 is simply referred to as a "gate electrode," the other is referred to as a "back gate." In addition, either the gate electrode 206 or the electrode 263 may be referred to as One may be called the "first gate electrode" and the other may be called the "second gate electrode."

[0190] In general, the back gate electrode is formed of a conductive film, and the gate electrode and the back gate electrode form a semiconductor. The back gate electrode is disposed so as to sandwich the channel forming region of the layer. The back gate electrode can be made to function in the same manner as the gate electrode. The potential of the back gate electrode may be changed, or may be set to the GND potential or any other potential. By changing the voltage, the threshold voltage of the transistor can be changed.

[0191] In addition, since the gate electrode and back gate electrode are made of a conductive film, they can be easily The function of preventing the electric field generated from acting on the semiconductor layer where the channel is formed (especially static electricity It also has electrostatic shielding function against

[0192] In addition, when light is incident from the back gate electrode side, the back gate electrode is By forming the semiconductor layer from a conductive film, light is prevented from entering the semiconductor layer from the back gate electrode side. This prevents light degradation of the semiconductor layer and shifts the threshold voltage of the transistor. This can prevent deterioration of electrical characteristics such as

[0193] By providing the gate electrode 206 and the electrode 263 with the semiconductor layer 208 sandwiched between them, By setting the electrode 206 and the electrode 263 at the same potential, carriers are The area in which the carriers flow becomes larger in the film thickness direction, and the amount of carrier movement increases. As a result, the on-state current of the transistor increases and the field-effect mobility increases.

[0194] The gate electrode 206 and the electrode 263 each have the function of blocking an external electric field. Therefore, the charges present in the layer below the gate electrode 206 and the layer above the electrode 263 are This does not affect the semiconductor layer 208. As a result, stress tests (e.g., applying a negative voltage to the gate) Gate Bias-Temperature (GBT) stress test The change in threshold voltage before and after the +GBT stress test is small. Also, it is necessary to suppress the fluctuation of the on-current rise voltage at different drain voltages. This can be done.

[0195] The BT stress test is a type of accelerated test that measures the transients that occur during long-term use. It is possible to evaluate the change in the characteristics of the BT string (i.e., the change over time) in a short time. The amount of change in the threshold voltage of a transistor before and after the load test is an important factor for examining reliability. The smaller the threshold voltage fluctuation before and after the BT stress test, the better the It can be said that this is a highly reliable transistor.

[0196] Also, the gate electrode 206 and the electrode 263 are included, and the gate electrode 206 and the electrode 26 By making the potentials of the transistors 3 the same, the amount of variation in the threshold voltage is reduced. At the same time, the variations in electrical characteristics of the transistors are reduced.

[0197] The transistor 232 formed in the display region 131 is provided with a back gate electrode. Good too.

[0198] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0199] (Fourth embodiment) The configuration of the display device 100 having the top emission structure is modified to remove the colored layer 266 and the light-shielding layer 26 4. It is possible to manufacture a display device 160 that does not include an overcoat layer 268 or the like.

[0200] 15A shows a cross-sectional configuration example of the display device 160. Note that FIG. 3(A) is a perspective view of the portion indicated by the dashed line X1-X2 in FIG. 3(A) and a cross-sectional view of a portion equivalent thereto. The display device 160 includes a light-shielding layer 264, a coloring layer 266, and an overcoat layer 26 Instead of providing the EL layer 8, the EL layer 117A, the EL layer 117B, the EL layer 117C (not shown) and the like are provided. By using the EL layer 117A, the EL layer 11 7B and others can emit different colors such as red, blue, and green. The EL layer 117A emits light 235A having a red wavelength, and the EL layer 117B emits light 235B having a red wavelength. The EL layer 117B emits light 235B having a blue wavelength, and the EL layer 117C emits light 235C having a green wavelength. Light 235C (not shown) is emitted.

[0201] Furthermore, by not using the colored layer 266, the light 235A, the light 235B, and the light 235 It is possible to eliminate the decrease in brightness that occurs when light 23 C passes through the colored layer 266. 5A, light 235B, and light 235C, the EL layer 117A, the EL layer 117B By adjusting the thickness of the EL layer 117C, color purity can be improved.

[0202] As with the display device 160, the configuration of the display device 150 having a bottom emission structure can be modified. The display device 1 does not include the colored layer 266, the light-shielding layer 264, the overcoat layer 268, etc. 15B shows an example of a cross-sectional structure of the display device 170. In FIG.

[0203] As shown in FIG. 27, optical films 911 such as a polarizing plate, a retardation plate, and a λ / 4 plate are added. The optical film 911 may be disposed by using the adhesive layer 148A or the adhesive layer 138A. This arrangement reduces reflections on the screen surface. In addition, the optical film 911 can be protected.

[0204] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0205] (Embodiment 5) As shown in FIG. 16(A), in the display device 100, a touch sensor is provided on a substrate 147. A substrate having a conductive layer 991 and a conductive layer 993 may be provided. In addition, an insulating layer 992 is provided between them.

[0206] The conductive layer 991 and / or the conductive layer 993 may be formed of indium tin oxide or indium zinc. It is desirable to use a transparent conductive film such as lead oxide. However, in order to reduce the resistance, 991 and / or the conductive layer 993 may be partially or entirely made of a layer having a low resistance material. For example, aluminum, titanium, chromium, nickel, copper, yttrium, di elemental metals consisting of zinc, molybdenum, silver, tantalum, or tungsten; or The alloy containing this as the main component can be used in a single layer structure or a laminated structure. Metal nanowires may be used as the layer 991 and / or the conductive layer 993. As the metal, silver is suitable. This can reduce the resistance value, The sensitivity of the sensor can be improved.

[0207] The insulating layer 992 may be made of silicon oxide, silicon nitride, silicon oxynitride, silicon nitride oxide, Aluminum oxide, aluminum oxynitride, or aluminum oxynitride, etc., can be used as a single layer or The insulating layer 992 is preferably formed in a multi-layer structure. The film can be formed by a method such as a coating method or a printing method.

[0208] Although the touch sensor is provided on the substrate 994, in one embodiment of the present invention, The present invention is not limited to this. It may be possible.

[0209] In addition, a substrate having a touch sensor is provided below the substrate 137 in the display device 150. An example of this case is shown in Figure 16(B).

[0210] As shown in FIG. 28, the touch sensor is attached to the substrate 121 via an adhesive layer 148A. Alternatively, it may be placed below the substrate 111 via an adhesive layer 138A.

[0211] The substrate 994 may have the function of an optical film. The transparent plate may have a function such as a polarizing plate or a retardation plate.

[0212] In addition, in the display device 100, a touch sensor may be formed on the substrate 121. A) is a method of forming a touch sensor on a substrate 121 and attaching a touch sensor to the substrate 121 via an adhesive layer 142. An example of forming a substrate 147 is shown.

[0213] In addition, in the display device 150, a touch sensor may be formed on the substrate 111. B) A touch sensor is formed on the substrate 111, and the touch sensor and the adhesive layer 138 are connected to each other. An example of forming a substrate 137 is shown.

[0214] In addition, in the display device 160, a touch sensor may be formed on the substrate 121. A) is a method of forming a touch sensor on a substrate 121 and attaching a touch sensor to the substrate 121 via an adhesive layer 142. An example of forming a substrate 147 is shown.

[0215] In addition, in the display device 170, a touch sensor may be formed on the substrate 111. B) A touch sensor is formed on the substrate 111, and the touch sensor and the adhesive layer 138 are connected to each other. An example of forming a substrate 137 is shown.

[0216] In addition, an optical film 911 may be disposed in Fig. 18. An example of this case is shown in Fig. 29. The optical film 911 is adhered via the adhesive layer 142A and the adhesive layer 138A. do.

[0217] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0218] (Embodiment 6) In this embodiment, a structural example of a light-emitting element that can be used as the light-emitting element 125 will be described. Note that the EL layer 320 in this embodiment may be the same as the EL layer 117 in other embodiments. is equivalent to

[0219] <Configuration of light-emitting element> The light-emitting element 330 shown in FIG. 19(A) has an EL element between a pair of electrodes (electrode 318 and electrode 322). In the following description of this embodiment, the layer 320 is taken as an example. Electrode 318 is used as an anode and electrode 322 is used as a cathode.

[0220] The EL layer 320 may be formed to include at least a light-emitting layer. The functional layer other than the light-emitting layer may be a layered structure including a functional layer having a high hole injection property. materials with high hole transporting properties, materials with high electron transporting properties, materials with high electron injecting properties, bipolar A layer containing a material having high electron and hole transport properties can be used. In practice, functional layers such as a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer are appropriately combined. It can be used as such.

[0221] The light emitting element 330 shown in FIG. 19(A) emits light in response to a potential difference generated between the electrode 318 and the electrode 322. This allows current to flow, and holes and electrons recombine in the EL layer 320, causing light to be emitted. In other words, the EL layer 320 is configured to have a light-emitting region.

[0222] In the present invention, light emitted from the light emitting element 330 is emitted from the electrode 318 or electrode 322 side. Therefore, either the electrode 318 or the electrode 322 has a light-transmitting property. It consists of a substance that

[0223] The EL layer 320 is connected to the electrode 318 and the electrode 331 as in the light-emitting element 331 shown in FIG. 19(B). It may be stacked in multiple layers between 22. When it has a stacked structure of n layers (n is a natural number of 2 or more), it is preferable to provide a charge generation layer 320a between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, respectively. When there is a case of having a stacked structure of n layers (n is a natural number of 2 or more), it is preferable to provide a charge generation layer 320a between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, respectively. Between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, it is preferable to provide a charge generation layer 320a respectively.

[0224] The charge generation layer 320a includes a composite material of an organic compound and a metal oxide, a metal oxide, a composite material of an organic compound and an alkali metal, an alkaline earth metal, or these compounds, and can be formed by appropriately combining these. As the composite material of an organic compound and a metal oxide, for example, it contains an organic compound and a metal oxide such as vanadium oxide, molybdenum oxide, or tungsten oxide. As the organic compound, various compounds such as aromatic amine compounds, carbazole derivatives, low molecular weight compounds such as aromatic hydrocarbons, or oligomers, dendrimers, polymers, etc. of these low molecular weight compounds can be used. Note that as the organic compound, a hole transport organic compound with a hole mobility of 10 cm / Vs or more is preferably applied. However, as long as it is a substance with higher hole transportability than electrons, other substances can be used. Note that these materials used for the charge generation layer 320a are excellent in carrier injection property and carrier transportability, so low current driving and low voltage driving of the light emitting element 330 can be realized. It may be formed by combining a composite material of an organic compound and a metal oxide with other materials. For example, a layer containing a composite material of an organic compound and a metal oxide and a layer containing a compound selected from electron donors and a compound with high electron transportability are combined. It may be stacked in multiple layers between 22. When it has a stacked structure of n layers (n is a natural number of 2 or more), it is preferable to provide a charge generation layer 320a between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, respectively. [[ID= (18]]When there is a case of having a stacked structure of n layers (n is a natural number of 2 or more), it is preferable to provide a charge generation layer 320a between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, respectively. Between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, it is preferable to provide a charge generation layer 320a respectively. It may be stacked in multiple layers between 22. When it has a stacked structure of n layers (n is a natural number of 2 or more), it is preferable to provide a charge generation layer 320a between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, respectively. -6 cm 2 / Vs or more is preferably applied. However, as long as it is a substance with higher hole transportability than electrons, other substances can be used. Note that these materials used for the charge generation layer 320a are excellent in carrier injection property and carrier transportability, so low current driving and low voltage driving of the light emitting element 330 can be realized. Between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, it is preferable to provide a charge generation layer 320a respectively. Note that these materials used for the charge generation layer 320a are excellent in carrier injection property and carrier transportability, so low current driving and low voltage driving of the light emitting element 330 can be realized. Between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, it is preferable to provide a charge generation layer 320a respectively. Between the m-th EL layer 320 (m is a natural number satisfying 1 ≤ m < n) and the (m + 1)-th EL layer 320, it is preferable to provide a charge generation layer 320a respectively.

[0225]

[0226] Alternatively, a layer containing a composite material of an organic compound and a metal oxide and a transparent conductive film may be combined. may be formed in combination with each other.

[0226] The light emitting element 331 having such a configuration may have problems such as energy transfer and quenching. It is difficult to achieve this, and the range of materials to choose from is widened, making it possible to create a light-emitting element that has both high luminous efficiency and a long life. It is also easy to obtain phosphorescence in one light-emitting layer and fluorescence in the other. is.

[0227] The charge generating layer 320a is a layer that generates a charge when a voltage is applied between the electrode 318 and the electrode 322. The electron-generating layer 320a has a function of injecting holes into the EL layer 320 formed in contact with the electron-generating layer 320a. The other EL layer 320 has a function of injecting electrons.

[0228] The light-emitting element 331 shown in FIG. 19(B) can be realized by changing the type of light-emitting material used in the EL layer 320. In addition, it is possible to obtain various luminescent colors by using a plurality of luminescent materials with different luminescent colors. By using luminescent materials, it is possible to obtain broad spectrum luminescence and white luminescence. do.

[0229] When white light is to be emitted using the light-emitting element 331 shown in FIG. 19(B), a combination of a plurality of EL layers is used. In combination, it is sufficient if the configuration includes red, blue, and green light and emits white light. For example, The light-emitting layer contains a blue fluorescent material as a light-emitting material, and the light-emitting layer contains green and red phosphorescent materials as light-emitting materials. In addition, a light-emitting layer that emits red light and a light-emitting layer that emits green light may be used. Alternatively, the light-emitting layer may have a structure including a light-emitting layer that emits blue light and a light-emitting layer that emits red light. White light can be obtained even if the device has a light-emitting layer that emits light of complementary colors. In a stacked element in which two layers are stacked, the color of the light emitted from one light-emitting layer is different from that from another light-emitting layer. When the luminescent colors obtained from the above are in a complementary color relationship, the complementary colors are blue and yellow, Examples of colors include blue-green and red.

[0230] In the configuration of the above-mentioned stacked element, a charge generating layer may be disposed between the stacked light emitting layers. By doing so, it is possible to realize a long-life element in the high-brightness region while maintaining a low current density. In addition, the voltage drop due to the resistance of the electrode material can be reduced, allowing for uniform generation over a large area. Light becomes possible.

[0231] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0232] (Embodiment 7) In this embodiment, examples of electronic devices and lighting devices to which the display device of one embodiment of the present invention is applied will be described. This will be explained with reference to the drawings.

[0233] As an example of an electronic device to which a display device having a flexible shape is applied, a television equipment (also called television or television receiver), monitors for computers, digital barrel cameras, digital video cameras, digital photo frames, mobile phones (mobile phones, (also called mobile phone devices), portable game machines, personal digital assistants, audio playback devices, pachinko machines, etc. Examples include large game consoles.

[0234] In addition, lighting devices and display devices can be installed on the interior or exterior walls of houses and buildings, or on the interior or exterior of automobiles. It is also possible to incorporate it along the curved surface of the

[0235] FIG. 20A shows an example of a mobile phone. The mobile phone 7400 has a housing 7401. In addition to the display unit 7402 incorporated in the The mobile phone 7400 is equipped with a speaker 7405, a microphone 7406, etc. The device is used in the display portion 7402 .

[0236] In the mobile phone 7400 shown in FIG. 20A, information can be displayed by touching the display portion 7402 with a finger or the like. You can also make calls, enter text, or do any other actions. An operation can be performed by touching the display portion 7402 with a finger or the like.

[0237] Also, by operating the operation button 7403, the power can be turned on and off, and the display unit 7402 can be displayed. For example, from the email creation screen, you can change the type of image displayed. - You can switch to the screen.

[0238] Here, the display device of one embodiment of the present invention is incorporated in the display portion 7402. As a result, a highly reliable mobile phone can be provided with a curved display.

[0239] FIG. 20B shows an example of a wristband-type display device. The device includes a housing 7101, a display unit 7102, operation buttons 7103, and a transmitting / receiving device 7104. can.

[0240] The portable display device 7100 can receive a video signal by the transmitting / receiving device 7104. Video can be displayed on the display unit 7102. Audio signals can also be transmitted to other receiving devices. It is also possible to do so.

[0241] In addition, the operation button 7103 can be used to turn the power on and off and to switch the displayed image. , or adjust the volume of the audio.

[0242] Here, the display device of one embodiment of the present invention is incorporated in the display portion 7102. As a result, a highly reliable portable display device can be provided that has a curved display portion.

[0243] 20(C) to 20(E) show an example of a lighting device. The lighting device 7210 and the illumination device 7220 are each mounted on a base 72 having an operation switch 7203. 01 and a light emitting part supported by a base part 7201.

[0244] The lighting device 7200 shown in FIG. 20(C) includes a light-emitting unit 7202 having a wavy light-emitting surface. This makes it a highly designed lighting device.

[0245] The light-emitting portion 7212 of the lighting device 7210 shown in FIG. 20(D) has two convexly curved The light emitting units are arranged symmetrically. It can illuminate the direction.

[0246] The lighting device 7220 shown in FIG. 20(E) includes a light-emitting portion 7222 that is curved in a concave shape. Therefore, in order to collect light emitted from the light emitting portion 7222 onto the front surface of the lighting device 7220, It is suitable for brightly lighting an area.

[0247] Furthermore, the light-emitting units of the lighting devices 7200, 7210, and 7220 Since the light emitting part is flexible, it can be attached to a plastic member or a movable frame. The light emitting portion may be fixed with a member, and the light emitting surface of the light emitting portion may be freely curved depending on the application.

[0248] Here, the light emitting devices 7200, 7210, and 7220 are The display device according to one embodiment of the present invention is incorporated in the display unit. Therefore, the lighting device can be bent into a desired shape and has high reliability.

[0249] Here, a cross-sectional view of the lighting device is shown in FIG.

[0250] FIG. 21A shows an example of a portable display device. The display device 7300 includes a housing 7301, It includes a display unit 7302, operation buttons 7303, a drawer member 7304, and a control unit 7305. .

[0251] The display device 7300 is a flexible display unit rolled up in a cylindrical housing 7301. Equipped with 7302.

[0252] The display device 7300 can receive a video signal through the control unit 7305. The control unit 7305 is provided with a battery. In addition, the control unit 7305 is provided with a connector, and a configuration is provided in which a video signal and power are directly supplied. Good too.

[0253] In addition, the operation button 7303 can be used to turn the power on and off and to switch the displayed image. etc. can be done.

[0254] FIG. 21B shows a state in which the display portion 7302 is pulled out by a pull-out member 7304 . In this state, an image can be displayed on the display portion 7302. The provided operation button 7303 allows for easy operation with one hand.

[0255] In order to prevent the display portion 7302 from bending when the display portion 7302 is pulled out, A frame for reinforcement may be provided at the end of 2.

[0256] In addition to this configuration, a speaker is provided on the housing, and the sound is transmitted by the audio signal received together with the video signal. The audio may be output by the audio input.

[0257] The display device of one embodiment of the present invention is incorporated in the display portion 7302. Since the unit 7302 is a flexible and reliable display device, the display device 7300 A lightweight and highly reliable display device can be obtained.

[0258] 22(A) and 22(B) illustrate a foldable tablet terminal 9600. FIG. 22(A) shows the tablet terminal 9600 in an open state. The terminal 9600 includes a housing 9630, a display unit 9631, and a display mode changeover switch 9626. , power switch 9627, power saving mode switch 9625, fastener 9629, operation The switch 9628 is also included.

[0259] The housing 9630 includes a housing 9630a and a housing 9630b. 0b are connected by a hinge portion 9639. The housing 9630 is connected by a hinge portion 96 39 allows it to be folded in half.

[0260] The display unit 9631 is connected to a housing 9630a, a housing 9630b, and a hinge 9639. By using the display device disclosed in this specification for the display portion 9631, The display portion 9631 can be bent, and a highly reliable tablet terminal can be provided. do.

[0261] A part of the display unit 9631 can be used as a touch panel area 9632, and the displayed operation Data can be input by touching the operation key 9638. For example, half of the area may be configured to have a display function only, and the other half may be configured as a touch panel. In addition, the entire area of ​​the display portion 9631 can be configured to have a touch panel function. For example, the entire surface of the display portion 9631 may be provided with keyboard buttons. It can also be used as a data entry terminal by displaying the screen.

[0262] A display mode changeover switch 9626 changes the display orientation between portrait and landscape. You can select between black and white and color display. The 9625 uses a built-in light sensor in the tablet device to detect external light during use. The display brightness can be optimized according to the amount of light. In addition, other detection devices such as gyro, acceleration sensor, etc. that detect tilt are also included. It may be stored.

[0263] FIG. 22(B) shows the tablet terminal 9600 in a closed state, and 9630, a solar cell 9633, and a charge / discharge control circuit 9634. 22(B) shows a battery 9635 as an example of a charge / discharge control circuit 9634, a DC / DC converter The configuration shown is with converter 9636.

[0264] By using the display device disclosed in this specification for the display portion 9631, For example, the tablet terminal 9600 can be folded in half, so The housing 9630 can be closed during use. The display portion 9631 can be protected by closing the housing 9630, which makes it highly durable and allows for long-term use. From this perspective, the tablet terminal can be made highly reliable.

[0265] In addition, the tablet terminals shown in Figs. 22(A) and 22(B) can store various information. Functions that display information (still images, videos, text images, etc.), calendars, dates, or times, etc. The function to display the information on the display unit, and the function to operate or edit the information displayed on the display unit by touch input. It has the function of controlling the processing by various software (programs), etc. This can be done.

[0266] The solar cell 9633 attached to the surface of the tablet terminal supplies power to the touch panel, The solar cell 9633 can be provided in the housing. If you install it on both sides of the body 9630 instead of just one, it will charge the battery 9635 more efficiently. The battery 9635 is preferably a lithium ion battery. The use of such a device has the advantage of enabling miniaturization.

[0267] The configuration and operation of the charge / discharge control circuit 9634 shown in FIG. 22(B) will be described with reference to FIG. ) shows a block diagram and explains. In FIG. 22(C), a solar cell 9633, a battery 96 35, DC-DC converter 9636, converter 9637, switches SW1 to SW3, The display unit 9631 is shown, along with the battery 9635 and the DC-DC converter 9636. The converter 9637 and the switches SW1 to SW3 constitute a charge / discharge control circuit shown in FIG. This corresponds to road 9634.

[0268] First, an example of operation when power is generated by the solar cell 9633 using external light will be described. The power generated by the solar cell is converted to a voltage to charge the Battery 9635. The voltage is increased or decreased by a C converter 9636. When power is being used from the battery 9633, the switch SW1 is turned on and the converter 96 37 increases or decreases the voltage to the voltage required for the display unit 9631. When not displaying in 31, turn SW1 off and SW2 on to charge the battery. 35 charging configuration.

[0269] The solar cell 9633 is shown as an example of a power generating means, but is not particularly limited thereto. Other power generation methods such as piezoelectric elements (piezoelectric elements) and thermoelectric elements (Peltier elements) For example, it may be configured to transmit and receive power wirelessly (contactlessly). A wireless power transmission module that charges by transmitting power, or a configuration that combines other charging methods It may also be possible to use the following.

[0270] Note that the display device of one embodiment of the present invention can be used in the electronic devices and lighting devices described above. It goes without saying that there is no particular limitation.

[0271] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is. [Example]

[0272] The display device 500 was fabricated by the fabrication method exemplified in the second embodiment. The substrate 111 and the substrate 121 were made of a 20 μm thick film. The substrates used were aramid with a Young's modulus of approximately 10 GPa. The silicone rubber used was 200 μm thick and had a Young's modulus of approximately 0.03 GPa.

[0273] Next, the entire display area of ​​the display device 500 is illuminated so that the bent portion overlaps the display area. The display device 500 was folded in half. FIG. 23(A) shows the display device 500 folded in half during light emission. A photo of the assembled state is shown below.

[0274] Next, the display device 500 that has been folded in half is unfolded again, and the display state of the display device 500 is checked. FIG. 23(B) shows a photograph of the display device 500 unfolded again. After folding, the entire display area remains illuminated even after unfolding, maintaining good display quality. was.

[0275] As a comparative example, a display device without the substrate 137 and the substrate 147 was used as the second embodiment. When the substrate 111 and the substrate 121 were folded in half, Cracks appeared in the display, and the entire display area could not maintain light emission. [Explanation of symbols]

[0276] 100 display device 101 Element formation substrate 111 Substrate 112 Adhesive layer 113 Peeling layer 114 Bulkhead 115 Electrode 117 EL layer 118 Electrode 120 Adhesive layer 121 PCB 122 Aperture 123 Anisotropic Conductive Interconnect Layer 124 External electrode 125 Light-emitting element 128 Aperture 129 Aperture 131 Display area 132 Drive circuit 133 Drive circuit 134 pixels 135 scan lines 136 Signal Line 137 PCB 138 Adhesive layer 141 Element formation substrate 142 Adhesive layer 143 Peeling layer 145 Insulating Layer 147 PCB 148 Adhesive layer 150 Display device 160 Display device 170 Display device 200 Display device 205 Insulation Layer 206 Gate electrode 207 Gate insulating layer 208 Semiconductor layer 210 Insulating layer 211 Insulating layer 216 Terminal electrode 219 Wiring 232 transistors 233 Capacitor 235 light 252 transistors 263 Electrode 264 Light blocking layer 266 Colored layer 268 Overcoat Layer 272 transistors 318 Electrode 320 EL layer 322 electrode 330 Light-emitting element 331 Light-emitting element 431 Transistor 432 Liquid crystal element 435 nodes 436 nodes 437 nodes 500 display device 991 Conductive layer 992 Insulation layer 993 Conductive layer 994 board 7100 Portable display devices 7101 Housing 7102 Display section 7103 Operation button 7104 Transmitting and receiving equipment 7200 Lighting Equipment 7201 Daibu 7202 Light-emitting part 7203 Operation switch 7210 Lighting equipment 7212 Light-emitting part 7220 Lighting equipment 7222 Light-emitting part 7300 display device 7301 Housing 7302 Display section 7303 Operation button 7304 Materials 7305 Control Unit 7400 mobile phone 7401 Housing 7402 Display section 7403 Operation button 7404 External connection port 7405 Speaker 7406 Microphone 9600 tablet device 9625 Switch 9626 Switch 9627 Power Switch 9628 Operation Switch 9629 Fasteners 9630 chassis 9631 Display section 9632 area 9633 Solar Cells 9634 Charge / Discharge Control Circuit 9635 Battery 9636 DC / DC Converter 9637 Converter 9638 Operation key 9639 Hinge part 117A EL layer 117B EL layer 117C EL layer 209a Source electrode 209b Drain electrode 235A light 235B light 235C light 320a Charge generation layer 9630a housing 9630b housing

Claims

1. A foldable display device, A first substrate having flexibility; a second substrate having flexibility; a rectangular third substrate between the first substrate and the second substrate; a rectangular fourth substrate between the first substrate and the second substrate; a light emitting element between the third substrate and the fourth substrate, a first substrate having a first side and a third side, the first side and the third side of the third substrate being covered by the first substrate; the first to third sides of the fourth substrate are covered by the second substrate; a fourth side of the third substrate is not covered by the first substrate; A display device, wherein a fourth side of the fourth substrate is not covered by the second substrate.

2. A foldable display device, A first substrate having flexibility; a second substrate having flexibility; a rectangular third substrate between the first substrate and the second substrate; a rectangular fourth substrate between the first substrate and the second substrate; a light emitting element between the third substrate and the fourth substrate, a first substrate having a first side and a third side, the first side and the third side of the third substrate being covered by the first substrate; the first to third sides of the fourth substrate are covered by the second substrate; a fourth side of the third substrate is not covered by the first substrate; a fourth side of the fourth substrate is not covered by the second substrate; the fourth substrate has an opening; A display device, wherein the terminal electrodes on the third substrate are electrically connected to external electrodes through the openings.

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