Display device

Abstract

To provide a highly reliable display device; to provide in particular, a display device to which a signal or a power supply potential can be supplied stably; and alternately to provide a bendable display device to which a signal or a power supply potential can be supplied stably.SOLUTION: A display device includes, over a flexible substrate, a display part, a plurality of connection terminals in which a signal from an outside can be input, and a plurality of wires. One of the plurality of connection terminals is electrically connected to the display part with one of the plurality of wires. The wire includes a first portion including a plurality of branched lines and a second portion formed by converging the plurality of lines into one.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a display device. In particular, one aspect of the present invention relates to a display device having a bendable display portion. Regarding the device. [Background technology]

[0002] In recent years, there has been a demand for diversification of the shapes of electronic devices with display functions. A display element is provided on a flexible substrate, and the display device can be curved or displayed along a curved surface. There is a demand for electronic devices equipped with a display device capable of displaying information. Also known as flexible displays, development is underway for practical use.

[0003] As a display element applicable to flexible displays, organic electroluminescence (EL) Luminescence elements, liquid crystal elements, etc. An electronic display that has elements that display using electrophoresis or electronic powder methods. Examples include paper.

[0004] For example, Patent Document 1 discloses a method for manufacturing an organic EL element on a resin substrate made of a flexible film. An organic EL display panel carrying the above-mentioned is disclosed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2006 / 046679 Brochure Summary of the Invention [Problem to be solved by the invention]

[0006] When incorporating a display device into an electronic device, a housing is required to supply signals and power potential to the display device. It is necessary to attach a connection wire to the display device to electrically connect the display device to the display device. The most typical wire is FPC (Flexible printed circuit). When attaching an FPC to a board, anisotropic conductive film (ACF) is used. The bonding is performed using a thermocompression bonding material such as a PTFE-coated conductive film.

[0007] However, in a display device having a display element on a flexible substrate, the display element is not easily attached by thermocompression bonding. There is a problem that the heat and pressure generated may damage the substrate and the wiring provided on the substrate. However, bending the substrate may cause the connection wiring to peel off from the substrate.

[0008] An object of one embodiment of the present invention is to provide a highly reliable display device. It is an object of the present invention to provide a display device capable of stably supplying a signal and a power supply potential. An object of the present invention is to provide a flexible display device capable of stably supplying signals and power supply potential. do.

[0009] The description of these problems does not preclude the existence of other problems. It is not necessary for one embodiment to solve all of these problems. The subject matter will be self-evident from the description, drawings, claims, etc. Other issues can be extracted from the drawings, claims, etc. [Means for solving the problem]

[0010] One embodiment of the present invention is a display device including a display unit and a display device to which a signal can be input from outside, which are provided over a flexible substrate. A display device having a plurality of connection terminals and a plurality of wirings, one of the connection terminals being connected to one of the wirings. The wiring is electrically connected to the display unit by a first portion which is branched into a plurality of wirings. and a second portion in which the multiple strands converge into one strand.

[0011] In the display device according to one embodiment of the present invention, the first portion of the wiring is It is preferred that the thickness of the first and second electrodes be less than that of the first electrodes.

[0012] Alternatively, in the display device according to one embodiment of the present invention, the first portion of the wiring is It is preferred that the thickness of the first and second electrodes be greater than the thickness of the second electrodes.

[0013] In the display device according to one embodiment of the present invention, the substrate has a region overlapping with the first portion of the wiring. It is preferable that the curved portion is curved at .

[0014] In the display device according to the embodiment of the present invention, the wiring is formed in a first portion. It is preferable that the wiring is arranged so that the bending direction does not coincide with the extending direction of the wiring.

[0015] In the display device according to one embodiment of the present invention, an IC is mounted on a substrate, and a plurality of wirings The other part electrically connects the IC and the display unit, and the IC is connected to the first part of the wiring. It is preferable that the device is provided between the child and the mother.

[0016] In this specification, when a surface is deformed from a flat state, the surface after deformation When the slope of the line connecting any two points along a surface is continuous, the surface is said to be curved. In this case, the deformed surface has a radius of curvature greater than 0 at any point.

[0017] In this specification, the term "flexible" means that a part of the device can be bent to a predetermined radius of curvature. This means that the specific function of the device is not lost when it is bent. A bendable display device is a device that can display information even when a part of the device is bent. Refers to a display device. Effect of the Invention

[0018] According to one embodiment of the present invention, a highly reliable display device can be provided. A display device capable of stably supplying a signal or power supply potential can be provided. It is possible to provide a display device that is bendable. [Brief description of the drawings]

[0019] [Figure 1] 1 shows a configuration example of a display device according to an embodiment. [Diagram 2] 4 shows an example of a wiring configuration of the display device according to the embodiment. [Diagram 3] 1 shows a configuration example of a display device according to an embodiment. [Figure 4] 4 shows an example of a wiring configuration of the display device according to the embodiment. [Diagram 5] 1 shows a configuration example of a display device according to an embodiment. [Figure 6] 4 shows an example of a wiring configuration of the display device according to the embodiment. [Figure 7] 1 shows a configuration example of a display device according to an embodiment. [Figure 8] 1A to 1C illustrate an example of a manufacturing method of a display device according to an embodiment. [Figure 9] 1 shows a configuration example of a display device according to an embodiment. [Figure 10] 1 shows a configuration example of a display device according to an embodiment. [Figure 11] 1 shows a configuration example of an electronic device according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The embodiment will be described in detail with reference to the drawings. However, the present invention is not limited to the following description. The present invention is not limited to the above embodiment, and various changes and modifications may be made in the form and details without departing from the spirit and scope of the present invention. It will be easily understood by those skilled in the art that the present invention can be realized by the following embodiments. The present disclosure should not be construed as being limited to the contents of the preceding paragraph.

[0021] In the configuration of the invention described below, the same parts or parts having similar functions are The same reference numerals are used in common between different drawings, and the repeated explanations are omitted. When referring to a function, the hatch pattern may be the same and no particular symbol may be used.

[0022] In each figure described in this specification, the size, layer thickness, or area of ​​each component is indicated by the following formula: The figures may be exaggerated for clarity and do not necessarily represent the relative size of each component. It is not limited to minor relationships.

[0023] 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 "device having some electrical function." "of" is not subject to any particular restrictions as long as it enables the transmission and reception of electrical signals between connected objects. For example, "something that has an electrical effect" includes electrodes, wiring, and transistors. Switching elements such as inverters, resistor elements, coils, capacitor elements, and other elements with various functions This includes circuits with various functions, etc.

[0024] (Embodiment 1) In this embodiment, a structural example of a display device according to one embodiment of the present invention will be described with reference to drawings. do.

[0025] [Example of display device configuration] FIG. 1(A) is a schematic top view of a display device 100 according to one embodiment of the present invention.

[0026] The display device 100 includes a display unit 102 and a plurality of wirings 111 on a flexible substrate 101. , a plurality of connection terminals 112, an IC 113, and a plurality of wirings 114.

[0027] The display unit 102 includes a pixel unit 103 and a driver circuit 104 .

[0028] The pixel section 103 has pixels each having a display element arranged in a matrix. In this way, an image can be displayed on the pixel portion 103 .

[0029] The display elements that can be applied to the pixels are organic EL (Electro Luminescence) nce) elements, liquid crystal elements, etc. Also, there are electrophoretic and electronic powder type elements The display device may be configured to include an element that performs display by the above method.

[0030] When organic EL elements are used as display elements in pixels, a backlight becomes unnecessary. In addition, when a backlight is required, such as when a liquid crystal element is used as the display element, the display device is preferably a liquid crystal display. In this case, when the substrate 101 is curved, the display portion of the substrate 101 is curved so as to follow the shape of the substrate. A flexible backlight may be attached to the side opposite to the surface on which 102 is provided.

[0031] The driving circuit 104 is a circuit for driving the pixels in the pixel section 103, and is, for example, a gate driving circuit. The driver circuit 104 may be a circuit having a function as a path. It is preferable that the light-emitting element is constituted by a semiconductor element such as a thin film transistor formed thereon. The driving circuit 104 does not necessarily have to be provided on the substrate 101. It may also have the function of the path 104.

[0032] As shown in FIG. 1(A), the substrate 101 has a shape with a part thereof protruding. Also, on the protruding portion of the substrate 101, a part of the plurality of wirings 111, a plurality of connection terminals 112, An IC 113 and wiring 114 are provided.

[0033] The connection terminal 112 is a terminal for connecting the display unit 10 to which a power supply voltage, an image signal, a timing signal, etc. are externally supplied. 2.

[0034] The IC 113 is a circuit having a function of driving the display unit 102, and is, for example, a source driving circuit. Alternatively, the circuit may be a circuit that functions as a signal path for an input image signal. Alternatively, the circuit may have a function of performing image processing using the input image data and generating a new image signal. As shown in (A), it is preferable to mount an IC 113 on a substrate 101. The IC 113 does not necessarily have to be mounted on the substrate 101. For example, the IC 113 may be mounted on a display device. An output signal from an IC 113 is input to the external device 100 via a connection terminal 112 and a wiring 111. The image may be input to the display device 100 as a signal.

[0035] One of the plurality of wirings 114 connects one of the plurality of connection terminals 112 to the IC 113. The wiring 114 is electrically connected to the connection terminal 112. A signal for driving the IC 113 or the display unit 102 is input to the IC 113. If this is not possible, the wiring 114 is not necessary.

[0036] The wiring 111 is disposed between the connection terminal 112 and the display unit 102. Reference numeral 11 denotes a display unit 102 electrically connected thereto, and transmits a signal for driving the display unit 102 to the display unit 102. For simplicity, the number of wirings 111 is reduced in FIG. Although this is shown explicitly, in reality, there are often many more wires than this.

[0037] The wiring 111 is a wiring that directly and electrically connects the connection terminal 112 and the display unit 102. The wiring is connected electrically to the IC 113 and the display unit 102. The common feature is that the display unit 102 has a function of transmitting a signal to drive the display unit 102. Therefore, in the following, these wirings will be collectively referred to as wirings 111.

[0038] A signal is input to a connection terminal 112 electrically connected to the display unit 102 via a wiring 111. The signal may be, for example, a signal for driving the driving circuit 104 or a signal for driving the IC 113. Examples of such signals include signals that include a voltage different from the power supply voltage.

[0039] In the configuration shown in FIG. 1A, an IC 113 is provided between the connection terminal 112 and the display unit 102. In order to provide such a function, the number of wirings 114 between the connection terminals 112 and the IC 113 and the indication of the IC 113 are 102 and the number of wirings 111 between the first and second sections 102 do not match.

[0040] The display device 100 is connected to the substrate 101 at a curved portion 110 that overlaps with the wiring 111 shown in FIG. The substrate 101 is bent so that a part of the substrate 101 on which the connection terminals 112 and the IC 113 are provided is separated from the display surface. It can be bent and folded back in the opposite direction.

[0041] FIG. 1B shows the display device 1 in a state where the substrate 101 is bent and folded back at the bending portion 110. 1B shows a schematic diagram of the display unit 102. In FIG. 1B, the display unit 102 is also curved in a concave shape. This shows the attitude.

[0042] As shown in FIG. 1B, a protrusion on which a connection terminal 112 and an IC 113 are provided on a substrate 101 is The protruding part can be bent and folded back to the opposite side of the display surface, so the display as seen from the display surface side The area occupied by the device 100 can be reduced, and the display device 100 can have a narrow frame. For example, when the display device 100 is incorporated into an electronic device, the size of the electronic device can be reduced. It can be realized.

[0043] In addition, a connection terminal 112 is provided on the folded portion of the substrate 101. 12 can be connected to a connector provided on the housing of an electronic device, for example. A part of the display device 100 can function similarly to the FPC. When an FPC is attached to a flexible display device, Eliminates problems such as wiring damage and FPC peeling off when the board 101 is bent. Therefore, a highly reliable display device can be realized.

[0044] As shown in FIG. 1B, the display device 100 has a display unit 102 curved in a convex or concave shape. Since the screen can be curved, it is possible to reproduce the curved surface as the image to be displayed. This allows for a variety of image expressions and applications that cannot be realized with flat display devices. It can be realized.

[0045] In addition, a flexible touch sensor may be provided so as to overlap the display unit 102 .

[0046] [About the wiring shape] Next, examples of the shape of the wiring 111 will be described. A schematic top view of a portion of line 111 is shown.

[0047] The wiring 111 has an opening in a part thereof, and is arranged so as to branch into a plurality of wires with the opening in between. In other words, the wiring 111 has a first portion 121 that is branched into a plurality of wires, The plurality of strands converge into a single second portion 122.

[0048] When a portion of the substrate 101 is curved, the curved portion 110 is arranged to overlap the first portion 121. It is preferable to curve the wire as shown in FIG.

[0049] Here, when a portion where wiring for transmitting signals to the display unit 102 is provided is curved, The stress caused by this can cause the wiring to crack, and in the worst case scenario, the wiring can break. When this occurs, a signal cannot be transmitted to the display unit 102, resulting in display defects. .

[0050] However, by forming the wiring 111 crossing the curved portion 110 in the above-mentioned shape, Even if one of the branched wires is broken, the signal can still be transmitted through the other branched wires. Therefore, display defects caused by bending are suppressed, and a highly reliable display is achieved. The display device 100 can be realized.

[0051] Here, as shown in FIG. 2B, in the first portion 121 of the wiring 111, It is preferable to make the line width of each of the multiple wirings as large as possible. This makes it possible to suppress an increase in resistance caused by branching the wiring 111. In addition, even if one or more of the branched wires are broken, the increase in resistance can be suppressed. This reduces the effects of signal delays and the like.

[0052] In FIG. 2, the wiring 111 is shown branched into three, but the number of branches is not limited to this. The more branches there are, the greater the risk of the wiring breaking when bent. can be reduced.

[0053] By forming the wiring 111 in such a shape, the curvature of the curved portion 110 of the substrate 101 is reduced. Since the diameter can be reduced, the display device 100 when a part of the substrate 101 is curved and folded back can be The total thickness of the display device 100 at the curved portion 110 can be reduced. The allowable value of the radius of curvature at the center position is 0.1 mm or more and 10 mm or less, preferably Reduce to 0.5 mm or more and 5 mm or less, more preferably 0.5 mm or more and 2 mm or less It is possible.

[0054] Here, in the display device 100 in the curved state shown in FIG. 1(B), An example of the cross-sectional configuration will be described with reference to FIG.

[0055] FIG. 3A is a schematic cross-sectional view including a curved portion 110 of the display device 100. indicates an area including the wiring 111, the IC 113, the wiring 114, and the connection terminal 112. .

[0056] In FIG. 3A, a wiring 111 is formed on a substrate 101, and a connection is further formed on the wiring 111. 1 shows a configuration in which a flexible substrate 131 is provided via a bonding layer 132.

[0057] The wires 111 and 114 to which the IC 113 is electrically connected have their ends exposed. In this manner, the upper layers, substrate 131 and adhesive layer 132, are opened. The bumps 134 of the IC 113 are electrically connected to the wiring 111 or the wiring 114 via the ACF 133. is connected to

[0058] In addition, an opening is formed in a portion of the wiring 114 through the substrate 131 and the adhesive layer 132 thereon, The upper surface of the wiring 114 is exposed. A part of the exposed wiring 114 serves as a connection terminal 112. It works like this.

[0059] Here, the first portion 121 of the wiring 111 has a thickness different from that of the second portion 122. It is preferable that

[0060] In FIG. 3A, the thickness of the first portion 121 of the wiring 111 is thinner than the thickness of the second portion 122. This shows the case where

[0061] In the curved portion 110, the upper and lower portions of the wiring 111 in the thickness direction are curved. Therefore, the first part of the wiring 111 overlapping the curved part 110 is different in stress. By reducing the thickness of the portion 121, the upper and lower portions of the wiring 111 are The difference in the stress applied to the wiring 111 can be reduced, and the wiring 111 can be prevented from being broken. Cut.

[0062] Furthermore, by reducing the thickness of the first portion 121 of the wiring 111, the wiring resistance increases. Therefore, it is preferable to use a low-resistance conductive material such as Cu for the first portion 121. Here, the wiring 111 is preferably made of different materials for the first portion 121 and the second portion 122. Alternatively, the same material may be used.

[0063] In addition, when the width of the first portion 121 of the wiring 111 is made larger than that of the second portion 122, This is preferable because it is possible to suppress an increase in the wiring resistance. When 121 is branched into a plurality of branches, the upper surface shape is made as shown in FIG. 2(B). This makes it possible to effectively suppress an increase in wiring resistance.

[0064] In FIG. 3B, the thickness of the first portion 121 of the wiring 111 is smaller than that of the second portion 122. The figure also shows the case where the thickness is thick.

[0065] By increasing the thickness of the first portion 121 of the wiring 111 that overlaps the curved portion 110, The mechanical strength of the wire 111 itself can be increased, and the breakage of the wire 111 due to bending can be prevented. It can be suppressed.

[0066] In addition, the upper surface of the first portion 121 is shaped like a plurality of wirings 111 as shown in FIG. In the case of branching, the thickness of the first portion 121 is increased to suppress an increase in wiring resistance. It is possible.

[0067] In addition, in FIG. 3, a substrate 131 is provided on the wiring 111 via an adhesive layer 132. However, as long as the surface of the wiring 111 is not exposed and is insulated, this configuration is not necessary. For example, the surface of the wiring 111 may be insulated by forming a resin on the wiring 111. By arranging the wiring 111, the thickness of the display device 100 in the area where the wiring 111 is provided can be reduced. In addition, at this time, the wiring 111 and the wiring 114 can be easily curved. By removing the resin on a part of the area to expose the surface, the wiring 111 and the wiring 114 can be A part of it can function as a connection terminal 112 .

[0068] FIG. 4 shows a schematic cross-sectional view of a part of the wiring 111.

[0069] As shown in FIG. 4(A), when making the thicknesses of the first portion 121 and the second portion 122 of the wiring 111 different, with the thick and thin portions having a single-layer structure of the same material, a part of the upper part of the wiring is removed by etching (also referred to as half-etching) to form the thin portion. This may be done.

[0070] Alternatively, the thick portion may have a laminated structure of two or more layers, and the thin portion may be configured by removing one or more of these layers.

[0071] FIGS. 4(B) and 4(C) show schematic cross-sectional views when the thick portion of the wiring 111 has a laminated structure of the wiring 111a and the wiring 111b.

[0072] As shown in FIG. 4(B), the wiring 111a may be laminated on the wiring 111b, and a part of the wiring 111a is removed by etching to form the thin portion of the wiring 111. At this time, if the materials of the wiring 111a and the wiring 111b are made different, when the wiring 111a is processed by etching, the upper surface of the wiring 111b will be etched, and it can be suppressed that it becomes thinner than the intended thickness, so this is preferable.

[0073] Also, as shown in FIG. 4(C), after a part of the wiring 111b is removed by etching, the wiring 111a is provided so as to cover the end of the wiring 111b, thereby forming the thick portion of the wiring 111. By adopting such a configuration, even if the same material is used for the wiring 111a and the wiring 111b, problems associated with etching do not occur, so this is preferable.

[0074] Here, the material used for the first portion 121 of the wiring 111 is a material having high ductility or malleability. It is preferable that the material contains a material having high ductility and malleability. If the wiring used in the bending portion 110 has high ductility, the wiring 111 may break due to bending. In addition, when the material is highly malleable, it becomes difficult to return the wiring to a flat state. The cracks of 11 are less likely to occur. Materials with high ductility and malleability include gold, silver, platinum, and iron. Metallic materials such as nickel, copper, aluminum, zinc, and tin, and alloys containing these metallic materials etc.

[0075] When the first portion 121 of the wiring 111 has a laminated structure of two or more layers, at least one layer Preferably, by using the above-mentioned materials for all layers, breakage or cracking of the wiring 111 can be suppressed.

[0076] The above is the explanation of the shape of the wiring.

[0077] [Other examples of display device configurations] The following describes an example of a display device having a configuration that is partially different from the display device 100 shown in FIG. He explains.

[0078] FIG. 5A shows an example of the display device 100 in which the IC 113 is not mounted.

[0079] In the display device 100 shown in FIG. 5A, the IC 113 and the wiring 114 are not provided. The display unit 102 and the connection terminal 112 are directly and electrically connected to each other via wiring 111. is.

[0080] In FIG. 5B, the curved portion 110 is not a protruding portion of the substrate 101 but is closer to the display portion 102. This shows a case where the display is located in a portion where the display surface is not visible. The area occupied by the display device 100 can be further reduced, and the display device 100 can have a narrow frame. .

[0081] In FIG. 5C, the curved portion 110 of the wiring 111 intersects with the curved portion 110 of the substrate 101. The wiring 111 is arranged so that its bending direction does not coincide with its extending direction. In other words, the wiring 111 is provided so as to cross the curved portion 110 obliquely.

[0082] The curved direction and extending direction of the wiring 111 will be described with reference to FIG.

[0083] First, the curvature direction of the surface will be explained with reference to FIG. 6(A). When the curved surface 141 is bent, the junction along the curved surface 141 is formed at any point on the curved surface 141. Here, as shown by the dashed line arrow in FIG. 6(A), The direction perpendicular to a tangent 142 in a plane tangent to an arbitrary point is defined as a curvature direction 143 .

[0084] Here, as shown in FIG. 6B, when any two points on the surface 141 are specified, A line 144 that connects the two points along the curved surface at the shortest distance is uniquely determined. At any point on the curved surface 141, if the line 144 is perpendicular to the tangent line 142, the curvature of the curved surface 141 is The direction coincides with the extension direction of the line 144.

[0085] Also, a line 144 that connects any two points on the curved surface 141 along the curved surface at the shortest distance; The angle between the tangent 142 and the line 144 is always equal at any point on the line 144. Since the line 142 and the curvature direction 143 are always perpendicular to each other, the angle between the line 144 and the tangent line 142 is acute. The angle obtained by subtracting the angle (including 90 degrees) from 90 degrees is the extension direction of the line 144. The angle between the direction of the line 144 and the direction of the curved surface 141 is called the angle. This corresponds to a case where the angle between the direction of curvature of curved surface 141 and the direction of curvature of curved surface 141 is 0 degrees.

[0086] 6C and 6D show the wiring 111 when the surface 145 on which the wiring 111 is formed is curved. This shows the state of 111.

[0087] In FIG. 6C, the extension direction of the wiring 111 coincides with the curvature direction of the formation surface 145 (parallel 10. The case where the wiring 111 is arranged so that

[0088] At this time, the radius of curvature of the wiring 111 along its extension direction is the minimum value, and the wiring 111 is This corresponds to a radius of curvature of 145.

[0089] In FIG. 6D, the extension direction of the wiring 111 is not aligned with the curvature direction of the formation surface 145. In other words, the wiring 111 is arranged in the following manner. The wiring 111 is arranged so that the angle between the direction of the wiring and the direction of curvature is greater than 0 degrees.

[0090] The angle between the extending direction of the wiring 111 and the bending direction is preferably, for example, 5 degrees or more and less than 90 degrees. The angle may be set to be generally 15 degrees or more and 60 degrees or less, and more preferably 30 degrees or more and 60 degrees or less.

[0091] At this time, the radius of curvature of the wiring 111 in the extending direction is equal to or larger than the radius of curvature of the surface 145 on which the wiring 111 is formed. Therefore, when the forming surface 145 is curved, the wiring 111 is prevented from being damaged or broken. The risk of wire breakage can be reduced, and a highly reliable display device can be realized.

[0092] Furthermore, when the wiring 111 is bent, there is a risk that the wiring 111 may be damaged or broken. The surface 145 (or the substrate 101) to be formed is curved with a radius of curvature smaller than the radius of curvature of the surface 145 (or the substrate 101). Therefore, when a part of the substrate 101 is curved and folded back, the display device 10 0 can be made thinner.

[0093] Next, FIG. 7 shows an example of the configuration of a display device different from that described above.

[0094] FIG. 7A shows the driving circuit that is provided near the protruding portion of the substrate 101 in FIG. Instead of the circuit 104, two driving circuits (driving circuits 104a and 104b) sandwiching the pixel unit 103 are provided. In particular, in a display device having a high-definition pixel section 103, It is preferable to divide the driving circuit into two parts as shown in FIG.

[0095] Depending on the form of the electronic device in which the display device 100 is incorporated, the display unit 102 may be curved. For example, there are electronic devices that can be folded back at a specific position. In such a case, it is necessary to repeatedly bend the display unit 102 at the same position. The driving circuits 104a and 104b also alternate between a flat state and a curved state. The electrical characteristics of elements such as transistors that configure the circuit 104a and the driver circuit 104b change. There is a risk that this will happen.

[0096] Therefore, as shown in FIG. 7B, the position where the display unit 102 overlaps with the curved portion 120 is It is preferable to divide the driver circuit so as to sandwich the driver circuit. The driving circuit 104a shown in FIG. 1 is connected to the driving circuit 104c and the driving circuit 104b so as to sandwich the two bending portions 120. 7A, the driving circuit 104d, and the driving circuit 104e. The driving circuit 104b is also divided into driving circuits 104f, 104g, and 104h. It is allocated.

[0097] FIG. 7(C) shows an enlarged view of the area enclosed by the dashed line in FIG. 7(B). Two separate drive circuits (drive circuits 104c and 104d) are provided, and each drive circuit is electrically 1 shows a plurality of pixels 150 efficiently connected and arranged in a matrix.

[0098] A plurality of wirings 151 are provided between the driving circuits 104c and 104d. The various signals for driving the driving circuit 104d input from 111 are transmitted to the driving circuit 104d. At this time, the circuit elements in the driving circuits 104c and 104d can be input to The spacing between the children (shift registers, buffers, etc.) is narrower than the spacing between the pixels 150. .

[0099] As shown in FIG. 7D, a part of the driving circuit 104c and a part of the driving circuit 104d are folded. By adopting such a configuration, the driving circuit 104c and narrowing the spacing between circuit elements (such as shift registers and buffers) in the driver circuit 104d. The driving circuits can be arranged at intervals similar to those in the case where they are not divided, without dividing the driving circuits. When the pixels 50 are arranged with high resolution, it is effective to arrange them in this way.

[0100] Although the case where the driving circuit is divided into three has been shown here, The number is not limited to this, and may be divided into two, four or more.

[0101] This concludes the description of other configuration examples of the display device.

[0102] This embodiment may be implemented in appropriate combination with other embodiment modes described in this specification. This can be done.

[0103] (Embodiment 2) An example of a method for manufacturing a display device according to one embodiment of the present invention will be described below.

[0104] [Example of manufacturing method] [Formation of release layer] First, a release layer 202 is formed on a support substrate 201 .

[0105] The support substrate 201 is a substrate that is at least heat resistant to the heat applied in the subsequent steps. The support substrate 201 may be, for example, a glass substrate, a resin substrate, a semiconductor substrate, a metal substrate, A ceramic substrate or the like can be used.

[0106] The peeling layer 202 is made of a high melting point metal material such as tungsten, titanium, or molybdenum. Preferably, tungsten is used.

[0107] The release layer 202 can be formed by, for example, a sputtering method.

[0108] [Formation of peeled layer and oxide layer] Next, a layer to be peeled 203 is formed on the peeling layer 202, and the peeling layer 202 and the layer to be peeled An oxide layer 211 is formed between the metal layer 203 and the metal layer 204 .

[0109] The layer 203 to be peeled off may be silicon oxide, silicon oxynitride, silicon nitride oxide, or nitride. Inorganic insulating materials such as silicon and aluminum oxide can be used. As the insulating layer 3, a layer containing the above-mentioned inorganic insulating material can be used as a single layer or a laminate. do.

[0110] In particular, the layer to be peeled 203 has a laminated structure of two or more layers, and the layer to be peeled 203 is most It is preferable to use a layer that releases hydrogen when heated as the adjacent layer. For example, the peeling layer 202 The silicon oxynitride layer and the silicon nitride layer are stacked from the side of the insulating layer.

[0111] In this specification, the term "silicon oxynitride" refers to a material that contains more than nitrogen as a component. It refers to a material that has a high oxygen content. On the other hand, the composition of the material has a higher nitrogen content than oxygen. This is called "silicon oxynitride."

[0112] The peeled layer 203 can be formed by a film forming method such as a sputtering method or a plasma CVD method. In particular, it is preferable to form the film by a plasma CVD method using a film forming gas containing hydrogen. stomach.

[0113] Here, the surface of the peeling layer 202 is oxidized during the formation of the peeled layer 203, so that the peeling An oxide layer 211 may be formed between layer 202 and the layer to be stripped 203 .

[0114] The oxide layer 211 is a layer containing an oxide of the metal contained in the peeling layer 202. The layer contains tungsten oxide.

[0115] Tungsten oxide is generally known as WO (3-x) It is expressed as WO3 and W2O5. , W4O 11 , WO2, and other non-stoichiometric compounds that can take on a variety of compositions. Oxide (TiO (2-x) ), and molybdenum oxide (MoO (3-x) ) is also a nonstoichiometric compound It is an object.

[0116] At this stage, the oxide layer 211 preferably contains a large amount of oxygen. For example, when tungsten is used as the peeling layer 202, the oxide layer 211 is mainly composed of WO3. It is preferable that the tungsten oxide is a tungsten oxide having the formula:

[0117] Here, before the layer to be peeled 203 is formed, dinitrogen monoxide gas is sprayed onto the surface of the peeling layer 202. A plasma treatment is performed in an atmosphere containing SiO 2 to form an oxide layer 211 on the surface of the peeling layer 202 in advance. By using such a method, the thickness of the oxide layer 211 can be controlled by changing the conditions of the plasma treatment. By changing the conditions, the oxidation rate can be reduced compared to when plasma treatment is not performed. This allows for improved control of the thickness of the material layer 211.

[0118] The thickness of the oxide layer 211 is, for example, 0.1 nm to 100 nm, preferably 0.5 nm. In addition, when the oxide layer 211 is extremely thin, may not be able to be confirmed.

[0119] A schematic cross-sectional view at this stage corresponds to FIG. 8(A).

[0120] [Heat Treatment] Subsequently, a heat treatment is performed to transform the oxide layer 211 .

[0121] By performing the heat treatment, hydrogen is released from the peeled layer 203 and is provided to the oxide layer 211. will be provided.

[0122] The metal oxide in the oxide layer 211 is reduced by the hydrogen supplied to the oxide layer 211, In the oxide layer 211, a plurality of regions having different oxygen compositions are mixed. For example, When tungsten is used as 202, the WO3 in the oxide layer 211 is reduced. A state with less oxygen (such as WO2) is generated, and these are mixed together. Such metal oxides show different crystal structures depending on the oxygen composition, so By providing a plurality of regions with different oxygen compositions in the oxide layer 211, the mechanical strength of the oxide layer 211 can be improved. As a result, a state where the oxide layer 211 is easily broken down is realized, and the subsequent This can improve the releasability in the peeling step.

[0123] The heat treatment is performed at a temperature equal to or higher than the temperature at which hydrogen is desorbed from the peeled layer 203 and below the softening point of the support substrate 201. In addition, the temperature may be set to a temperature at which a reduction reaction between the metal oxide in the oxide layer 211 and hydrogen occurs. For example, when tungsten is used for the peeling layer 202, Heat to a temperature of 450°C or higher, 600°C or higher, or 650°C or higher.

[0124] The higher the temperature of the heat treatment, the greater the amount of hydrogen desorbed from the peeled layer 203. However, in consideration of the heat resistance of the support substrate 201 and productivity, In order to lower the heating temperature, the peeling layer 202 may be preliminarily subjected to plasma treatment as described above. By forming the oxide layer 211 by heat treatment, high peeling can be achieved even if the heat treatment temperature is low. It is possible to achieve this.

[0125] [Formation of display section and wiring] Next, the display unit 102, the wiring 111, and the wiring 114 are formed on the peeled layer 203 ( Figure 8(B)).

[0126] The display unit 102 includes at least a display element, and in addition to the display element, The display element may include wiring for connecting the display element and a transistor for use in a circuit for controlling driving of the display element.

[0127] A bottom gate transistor is manufactured as a transistor included in the display portion 102. In this case, a gate electrode, a gate insulating layer, a semiconductor layer, a source electrode, and A drain electrode is formed in this order, whereby a transistor can be manufactured.

[0128] The transistor configuration may be a staggered transistor, an inverted staggered transistor, etc. In addition, either a top-gate type or a bottom-gate type transistor may be used. Also, a channel etch type transistor or a channel protection type transistor may be used. In the case of a channel protection type, a channel Alternatively, a protective film may be provided on the portion where the source / drain electrode and the semiconductor layer are in contact with each other. An opening may be provided only in the channel protection film, and a channel protection film may be provided in places other than the opening.

[0129] Examples of semiconductors that can be used in the semiconductor layer in which the channel of a transistor is formed include silicon. Semiconductor materials such as silicon and germanium, compound semiconductor materials, organic semiconductor materials, or oxide Semiconductor materials may also be used.

[0130] The crystallinity of the semiconductor used in the transistor is not particularly limited. A semiconductor having crystallinity (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a partially crystalline semiconductor) If a semiconductor having crystallinity is used, the This is preferable since it suppresses the deterioration of the transistor characteristics.

[0131] For example, when silicon is used as the semiconductor, amorphous silicon, microcrystalline silicon, For example, silicon, polycrystalline silicon, or single crystal silicon can be used.

[0132] In addition, when an oxide semiconductor is used as the semiconductor, indium, gallium, zinc oxide, It is preferable to use an oxide semiconductor containing at least one of the following: -Zn-based metal oxides are examples of these. They have a wider band gap than silicon and are By using an oxide semiconductor with a low rear density, leakage current in the off state can be suppressed. This is preferable.

[0133] In addition, a display element provided in the display unit 102 is a light-emitting organic compound By forming a light emitting element having a layer including For example, a flexible lighting device having a light emitting element can be manufactured. It is also possible to create devices (or light sources) using transistors and light-emitting elements such as light-emitting devices and liquid crystal elements. A plurality of pixels including a display element are formed on the peeled layer 203, thereby forming an image display device. An example of a flexible image display device will be described in a later embodiment.

[0134] Here, the wiring 111 and the wiring 114 are the same as the wiring and electrodes that constitute a part of the display unit 102. For example, the gate electrode and source electrode of a transistor are preferably formed by processing a single layer. A transistor and a light-emitting element are electrically connected to each other. Examples of wiring that connect to the

[0135] FIG. 8B illustrates an example in which the wiring 111 has a stacked structure of a wiring 111b and a wiring 111a. The portion of the wiring 111 where only the wiring 111a is formed corresponds to the first portion, and The portion of the line 111 where the wiring 111a and the wiring 111b are laminated corresponds to the second portion. The wiring 114 has the same configuration as the second portion of the wiring 111. The wiring 111b is made of the same material as the gate electrode of the transistor. By using the same material as the source electrode or drain electrode, wiring 11 can be formed without increasing the number of processes. 1 can be formed.

[0136] [Lamination] Next, the support substrate 201 and the substrate 131 are bonded together via the adhesive layer 132 (FIG. 8( C).

[0137] It is preferable to use a flexible substrate as the substrate 131. For example, a substrate made of polyethylene In addition to resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), A metal substrate, a glass substrate, or the like that is thin enough to have flexibility can be used. A composite material in which two or more of metal, glass, or resin are laminated may also be used.

[0138] In addition, when resin is used as the substrate 131, impurities such as water may be present on any of its surfaces. It is preferable to provide a barrier layer that is difficult to penetrate. For example, silicon oxide, oxynitride, etc. A layer of silicon oxide, silicon nitride, silicon nitride, aluminum oxide, etc. is provided. It's fine.

[0139] The adhesive layer 132 may be made of any material capable of bonding the surfaces to be bonded together, such as a thermosetting resin or a purple adhesive. Radiation curable resins can be used. For example, acrylic, urethane, epoxy, or silicone. Resins such as resins having hexane bonds can be used. In the case of removing the organic solvent, a water-soluble resin or a resin soluble in an organic solvent may be used.

[0140] [Peeling] Next, the peeling layer 202 and the layer to be peeled 203 are peeled off from each other with the oxide layer 211 as a boundary (FIG. 8(D)).

[0141] As a method of peeling, for example, the support substrate 201 or the substrate 131 is fixed to a suction stage. In this way, a peeling starting point is formed between the peeling layer 202 and the layer to be peeled 203. The starting point for detachment may be formed by inserting a sharp tool such as a sharp object into the skin. The peeling layer 202 is melted, evaporated, or thermally destroyed by irradiating the peeling layer 202 with laser light. It may also form the starting point of peeling. Also, liquid (e.g., alcohol, water, water containing carbon dioxide) ) is dropped onto the edge of the release layer 202, and the liquid is made to cover the release layer 202 by utilizing the capillary phenomenon. The starting point of peeling may be formed by penetrating the boundary of the peeling layer 203 .

[0142] Next, in the portion where the peeling starting point was formed, the adhesive surface was gently pulled in the direction perpendicular to the peeling starting point. By applying a physical force to the layer to be peeled, the layer to be peeled 203 can be peeled without being damaged. At this time, tape or the like is attached to the support substrate 201 or the substrate 131, and the tape is The peeling may be performed by pulling in the above direction, or the hook-shaped member may be attached to the support substrate 201 or the substrate. The peeling may be performed by hooking it onto the edge of the plate 131. Also, adhesive materials or materials capable of vacuum suction may be used. The member is attached to the back surface of the support substrate 201 or the substrate 131 and pulled to remove the member. Alternatively, a sticky roller may be pressed against the back surface of the support substrate 201 or the substrate 131. The adhesive may be applied to the roller and then peeled off by moving the roller while rotating it.

[0143] Here, during peeling, a liquid containing water, such as water or an aqueous solution, is added to the peeling interface, and the liquid is peeled off. By performing the peeling so as to penetrate into the interface, the peeling properties can be improved.

[0144] The peeling occurs mainly inside the oxide layer 211 and at the interface between the oxide layer 211 and the peeling layer 202. Therefore, as shown in FIG. 8D, the surface of the peeling layer 202 after peeling and the surface to be peeled are An oxide layer 211 may be attached to the surface of the layer 203. The oxide layer 211a attached to the 203 side and the oxide layer 211b attached to the peeling layer 202 side are Note that the thicknesses of the deposited oxide layers 211a and 211b are different. Since the oxide layer 211 and the peeling layer 202 are easily peeled off at the interface between them as described above, In many cases, the adhesive is thickly attached to the layer 203 to be peeled.

[0145] [Lamination] Thereafter, as shown in FIG. 8(E), the substrate is attached to the peeled surface side of the peeled layer 203 via the adhesive layer 135. The plate 101 is attached. Materials that can be used for the adhesive layer 135 and the substrate 101 include , the adhesive layer 132 and the substrate 131 described above can be taken into consideration.

[0146] [Exposed wiring] Next, in order to expose a part of the surface of the wiring 111 and the wiring 114, the substrate 131 and the wiring A portion of the adhesion layer 132 is removed to form an opening (FIG. 8(F)).

[0147] For example, if the substrate 131 is made of resin, the opening is surrounded by masking tape. A solvent that dissolves the substrate 131 and the adhesive layer 132 is dropped onto the opening. The dissolved substrate 131 and adhesive layer 132 are wiped off, so that the wiring 111 and the wiring 114 are An opening that exposes a portion of the substrate can be formed. Alternatively, the substrate can be formed so as to surround the portion to be exposed. A cut is made from the top surface of 131 using a blade such as a cutter, and the substrate 131 and the adhesive layer 132 are separated from each other. Alternatively, the substrate 131 and the adhesive layer 132 may be peeled off by laser irradiation or the like. A portion of 132 may be removed.

[0148] Through the above steps, a display device of one embodiment of the present invention can be manufactured.

[0149] The display unit 102, the wiring 111, and the wiring 114 are formed on the substrate 101 having flexibility. The method of forming the display unit 102, the wiring 111, and the like directly on the substrate 101 is not limited to the above. The wiring 114 may be formed. If the display unit 1 is heat resistant to the heat applied in the formation process, the display unit 1 is directly formed on the substrate 101. It is preferable to form the wiring 111 and the wiring 114 because the process can be simplified. At this time, the display section 102, the wiring 111 and the wiring 114 are fixed to the substrate 101 on the support base material. The formation of the fluororesin facilitates transport within and between the equipment used to form the fluororesin. This is preferable.

[0150] In addition, the combination of the release layer and the layer to be peeled is not limited to the above. A material that causes peeling to occur at the interface with the layer or in the peeling layer can be selected. For example, A combination of materials with low adhesion, such as resin, may also be used.

[0151] In addition, if peeling can be performed at the interface between the support substrate and the layer to be peeled off, it is not necessary to provide a peeling layer. For example, glass is used as the support substrate, and an organic resin such as polyimide is used as the peeled layer. In this case, the organic resin may be heated to perform the peeling. A metal layer is provided between layers to be peeled off, which are made of resin, and an electric current is passed through the metal layer to heat the metal layer. By this, peeling may be performed at the interface between the metal layer and the layer to be peeled.

[0152] This embodiment may be implemented in appropriate combination with other embodiment modes described in this specification. This can be done.

[0153] (Embodiment 3) In this embodiment, a more specific configuration example of the display device illustrated in Embodiment 1 will be described. The following description will be given with reference to the drawings. An example of an image display device to which an organic EL element is applied will be described below. He explains.

[0154] [Display device configuration example 1] FIG. 9 shows a schematic cross-sectional view of a display device 300 that employs a top emission method. FIG. 9 shows a schematic top view of the display device 300. FIG. 1 can be referred to for the schematic top view of the display device 300 shown in FIG. FIG. 9 is a cross-sectional view of a region including the display unit 102, the wiring 111, and the connection terminal 112 in FIG. 1 corresponds to a schematic cross-sectional view of the

[0155] The display device 300 is a display device in which a peelable layer 2 is attached to a flexible substrate 354 via an adhesive layer 135. 03. Also, on the peeled layer 203, a pixel portion 103 having a light emitting element 340 and a driving The circuit 104, the wiring 111, and the connection terminal 112 are included. 3 is provided facing the substrate 354 with the sealing layer 352 interposed therebetween.

[0156] The wiring 111 has a first portion 121 and a second portion 122 that have different thicknesses. The thicker portion of 11 (second portion 122 in FIG. 9) is a gate of a transistor, which will be described later. The semiconductor device has a laminated structure of a conductive film that is the same as the gate electrode and a conductive film that is the same as the source electrode and the drain electrode. In addition, the thin portion of the wiring 111 (first portion 121 in FIG. 9) is a transistor. The wiring 111 is made of the same conductive film as the source and drain electrodes of the transistor. A part of the surface is exposed to form a connection terminal 112 .

[0157] Materials that can be used for electrodes and wiring that make up transistors and display elements include A Gold such as l, Ti, Cr, Co, Ni, Cu, Y, Zr, Mo, Ru, Ag, Ta and W Metals, alloys containing the above-mentioned metals, or nitrides of the above-mentioned metals can be used. The wiring 111 is made of the same conductive film as the electrodes and wiring that constitute the transistors and the display elements. When processing and forming a material, the thickness is often thin enough that it has poor ductility and malleability. Even if the material is thin, damage or breakage due to bending can be suppressed.

[0158] FIG. 9 shows n-channel transistors 311 and 312 as part of the driver circuit 104. The driving circuit 10 has a transistor 312. 4 is not limited to circuits combining n-channel transistors, Various CMOS circuits that combine p-channel and p-channel transistors A circuit having a combination of transistors of the same type may be used.

[0159] FIG. 9 shows a cross-sectional structure of one pixel as an example of the pixel section 103. A switching transistor 313, a current control transistor 314, and a current control transistor 315. The first transistor 314 is electrically connected to an electrode (source electrode or drain electrode) of the first The first electrode 333 includes an insulating layer 319 that covers an end of the first electrode 333. .

[0160] The light-emitting element 340 includes a first electrode 333, an EL layer 335, a second electrode 336, and a second electrode 337 disposed on an insulating layer 317. The display device 300 illustrated in this configuration example is a top-emitting type. Since the display device is a display device to which the formula is applied, a light-transmitting material is used for the second electrode 337. The first electrode 333 is preferably made of a reflective material. The EL layer 335 is sandwiched between a first electrode 333 and a second electrode 337. A voltage is applied between the EL layer 335 and a current is passed through the EL layer 335, causing the light-emitting element 340 to emit light. It is possible.

[0161] On the surface of the flexible substrate 353 facing the substrate 354, a bonding layer 342 is formed. The peeled layer 343 is provided. A color filter is provided at a position on the peeled layer 343 facing the light emitting element 340. The insulating layer 319 is overlapped with a black matrix 322. The layer to be peeled 343 is a layer made of the same material as the layer to be peeled 203.

[0162] In addition, on the surface of the substrate 353 that does not face the substrate 354, wiring made of a transparent conductive film is provided. A touch sensor may be formed by using a flexible substrate other than the substrate 353 and the substrate 354. A touch sensor formed on a substrate having the touch sensor may be provided on the substrate on the light emitting side. In addition, when a touch sensor including an optical sensor is applied, a plurality of photoelectric conversion elements are provided in the pixel unit 103. The switching elements are arranged in a matrix.

[0163] The layer to be peeled 203 and the layer to be peeled 343 are included in the substrate 354 or the substrate 353, respectively. It is preferable that the semiconductor device has a function of suppressing diffusion of impurities. The insulating layer 316 and the insulating layer 318 in contact with the semiconductor layer are provided to suppress the diffusion of impurities into the semiconductor layer. These insulating layers are preferably made of semiconductors such as silicon or aluminum. Any of the metal oxides or nitrides can be used. Alternatively, a laminated film of an inorganic insulating material and an organic insulating material may be used.

[0164] Examples of the inorganic insulating material include aluminum nitride, aluminum oxide, and aluminum nitride oxide. Aluminum, aluminum oxide nitride, magnesium oxide, gallium oxide, silicon nitride, Silicon oxide, silicon nitride oxide, silicon oxynitride, germanium oxide, zirconium oxide Materials selected from the group consisting of lanthanum oxide, neodymium oxide, and tantalum oxide can be used. The above materials may be used in a single layer or in a laminated form. The term "oxidation" refers to a material whose composition contains more nitrogen than oxygen, and is therefore called oxynitridation. indicates that the composition contains more oxygen than nitrogen. For example, Rutherford Backscattering Analysis (RBS Analysis) It can be measured using ion scattering spectrometry (ICS) etc. In addition, hafnium silicate (HfSiO x ), nitrogen is added Added hafnium silicate (HfSi x O y N z ), hafnium aluminium doped with nitrogen Luminate (HfAlx O y N z ), hafnium oxide, yttrium oxide, etc. k-materials may also be used.

[0165] Here, the layer to be peeled 343 can be manufactured by applying the method exemplified in the second embodiment. That is, a peeling layer, an oxide layer, and a peeled layer 343 are formed on a support substrate, and the peeled layer After forming the color filter 321 and the black matrix 322 on the substrate 343, the substrate 343 is peeled off. Then, a substrate 353 is attached to the back side of the peeled layer 343 via an adhesive layer 342. As a result, the configuration shown in FIG. 9 can be obtained.

[0166] 9, between the peeled layer 203 and the adhesive layer 135, or between the peeled layer 343 Between the oxide layer 211a and the adhesive layer 342, the oxide layer 211a or the oxide layer 341 may be provided. The oxide layer 211a and the oxide layer 341 are extremely thin and have light transmitting properties. Even if it is installed on the side where light is emitted from 40, there is almost no risk of reducing the light emission efficiency. do not have.

[0167] Here, the peeled layer 203 on which the transistors and the like are formed and the color filter 321 and the like are formed. When the formed peeled layer 343 and the sealing layer 352 are bonded to each other, they are peeled off. The substrates are then bonded together while they are mounted on the support substrates. It is preferable to peel the substrate from the plate. In the case where high accuracy is required for the alignment of the color filter 321 with the pixels, the glass By bonding the parts while they are fixed to a supporting substrate, these positions can be determined with high precision. This method allows high-definition flexible A display device can be realized.

[0168] In FIG. 9, a case where a light-emitting element is used as a display element is shown. The embodiment is not limited to this. As the display element, a liquid crystal element or an electrophoretic element (electronic paper) When an electrophoretic element is used, a backlight is not required. Therefore, it is suitable as one embodiment of a flexible display device.

[0169] [Display device configuration example 2] In this configuration example, a display device that uses a bottom emission method is explained. Note that a description of parts that overlap with the above-mentioned configuration example 1 will be omitted.

[0170] FIG. 10 is a schematic cross-sectional view of a display device 350 illustrated in this configuration example.

[0171] The display device 350 differs from the display device 300 illustrated in the configuration example 1 mainly in the following points. In the display device 350, the color filter 321 is disposed closer to the substrate 354 than the light emitting element 340. In addition, a flexible substrate 353 is provided in direct contact with the sealing layer 352. 1. The display device 300 does not have the peeled layer 343 or the adhesive layer 342 .

[0172] In the light-emitting element 340, the first electrode 333 is made of a light-transmitting material, and the second electrode 33 A reflective material is used for the EL layer 335. Therefore, the light emitted from the EL layer 335 is reflected toward the substrate 354. It is ejected.

[0173] In addition, a color filter is formed on the insulating layer 318 that covers the transistor at a position that overlaps the light emitting element 340. Further, an insulating layer 317 is provided to cover the color filter 321. It is provided.

[0174] Here, the substrate 353 is made of a material that does not allow impurities such as water to penetrate from the outside of the substrate 353. Alternatively, the above-mentioned material is preferably used on the surface of the substrate 353 that contacts the sealing layer 352. A film containing an insulating material having a function of suppressing the diffusion of impurities is provided. is preferred.

[0175] [Materials and forming method] The materials and forming methods that can be used for each of the above-mentioned elements will be described below. .

[0176] [Flexible Substrate] The flexible substrate material may be an organic resin or a thin glass material that is flexible. etc. can be used.

[0177] For example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN ) and other polyester resins, polyacrylonitrile resins, polyimide resins, polymethylmethacrylate resins, etc. Acrylate resin, polycarbonate (PC) resin, polyethersulfone (PES) resin , polyamide resin, cycloolefin resin, polystyrene resin, polyamide-imide resin, Polyvinyl chloride resin, etc. are examples. In particular, it is preferable to use a material with a low thermal expansion coefficient. For example, the thermal expansion coefficient is 30×10 -6 Polyamide-imide resin, polyimide Mido resin, PET, etc. can be suitably used. In addition, a substrate ( Prepreg (also called prepreg) or a substrate with a lower thermal expansion coefficient by mixing inorganic filler with organic resin is used. It can also be used.

[0178] When the above-mentioned materials contain fibrous bodies, the fibrous bodies are made of high strength organic or inorganic compounds. High strength fibers are specifically fibers with high tensile modulus or Young's modulus. Representative examples are polyvinyl alcohol fibers, polyester fibers, and polyvinyl alcohol fibers. Mid fiber, polyethylene fiber, aramid fiber, polyparaphenylene benzobisoxy Examples of the fiberglass include Sasol fiber, glass fiber, and carbon fiber. Examples of glass fibers include those made of glass fiber such as sappan, S-glass, D-glass, and Q-glass. Alternatively, it is used in the form of a nonwoven fabric, and the structure in which the fiber body is impregnated with resin and the resin is hardened is made flexible. As a substrate having flexibility, a substrate made of a fiber body and a resin may be used. The use of a structure is preferable because it improves reliability against damage caused by bending or local pressure. stomach.

[0179] The flexible substrate on the side from which light from the light emitting element 340 is extracted is provided with a layer of EL layer 335. A material that is transparent to light emitted is used. The material on the light exit side is In order to improve efficiency, it is preferable that the refractive index of the flexible and light-transmitting material is high. For example, by dispersing inorganic fillers with a high refractive index in an organic resin, a composite material consisting of only the organic resin can be obtained. This allows the realization of a substrate with a higher refractive index than substrates made of inorganic fillers with particles of 40 nm or less. The use of lasers is preferred since they do not impair optical clarity.

[0180] In addition, the substrate provided on the side opposite to the light exiting side does not need to have light transmitting properties. In addition to the substrates listed above, metal substrates and the like can also be used. The thickness of the metal substrate depends on its flexibility and bending properties. In order to obtain good adhesion, the thickness is 10 μm or more and 200 μm or less, preferably 20 μm or more and 50 μm or less. The material constituting the metal substrate is not particularly limited, but examples thereof include Aluminum, copper, nickel, or alloys of metals such as aluminum alloys or stainless steel A metal such as gold can be preferably used. Alternatively, when a conductive substrate containing an alloy material is used, the heat generated by the light emitting element 340 can be dissipated. This is preferable because it increases the efficiency.

[0181] In addition, when a conductive substrate is used, the surface of the substrate is oxidized or insulated. It is preferable to use a substrate that has been subjected to an insulating treatment, such as by forming an insulating film. coating methods such as spin coating and dipping, printing methods such as screen printing, and deposition methods. An insulating film is formed on the surface of a conductive substrate using deposition methods such as sputtering. Alternatively, the base may be removed by leaving it in an oxygen atmosphere or heating it, or by anodizing. The surface of the plate may be oxidized.

[0182] In addition, when the surface of a flexible substrate has an uneven shape, the uneven shape is covered to form a flat surface. A planarizing layer may be provided to form a flat insulating surface. The material can be organic or inorganic. The planarizing layer can be formed by deposition methods such as sputtering, coating methods such as spin coating and dipping, Using ejection methods such as the inkjet method and the dispense method, and printing methods such as the screen printing method, etc. It can be formed by

[0183] In addition, a material having multiple layers laminated thereon can also be used as a flexible substrate. For example, a material made of two or more layers of organic resins, a material made of an organic resin layer and an inorganic material layer, Materials that have layers of different inorganic materials stacked together, or materials that have layers of two or more different inorganic materials stacked together, etc. By providing a layer made of organic material, the infiltration of moisture and other substances into the interior is suppressed, so the light-emitting device This can improve the reliability of the device.

[0184] As the inorganic material, metal or semiconductor oxide materials, nitride materials, oxynitride materials, etc. are used. For example, silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, etc. Aluminum, aluminum nitride, aluminum oxynitride, etc. may be used.

[0185] For example, when a layer made of an organic resin and a layer made of an inorganic material are laminated, The inorganic material is deposited on or under the layer by a sputtering method, a CVD method, a coating method, or the like. A layer of material can be formed.

[0186] [Light-emitting element] In the light emitting element 340, the electrode provided on the light emitting side is A light-transmitting material is used.

[0187] Examples of materials having light-transmitting properties include indium oxide, indium oxide tin oxide, and indium oxide. Zinc oxide doped with gallium, zinc oxide, zinc oxide doped with gallium, etc. can be used. The conductive layer of the electrode may be made of gold, silver, platinum, or magnesium. Sium, Nickel, Tungsten, Chromium, Molybdenum, Iron, Cobalt, Copper, Palladium Alternatively, metal materials such as titanium and alloys containing these may be used. Nitrides of these metal materials (for example, titanium nitride) may also be used. In the case of using a thin film or a nitride thereof, it is sufficient to make the film thin enough to have light transmitting properties. A laminate of materials can be used as the conductive layer of the electrode. For example, silver and magnesium The conductivity can be increased by using a laminated film of an alloy of indium oxide and indium tin oxide. Therefore, it is preferable.

[0188] Such electrodes are formed by deposition or sputtering. The shape is formed using a discharge method such as the inkjet method, a printing method such as the screen printing method, or a plating method. It can be achieved.

[0189] In addition, when the above-mentioned conductive oxide having light-transmitting properties is formed by a sputtering method, When the conductive oxide is formed in an atmosphere containing argon and oxygen, the light transmittance is improved. It is possible.

[0190] In addition, when a conductive oxide film is formed on an EL layer, a conductive oxide film containing argon with a reduced oxygen concentration is used. A first conductive oxide film formed under an atmosphere containing argon and oxygen, and a second conductive oxide film formed under an atmosphere containing argon and oxygen. When the second conductive oxide film is laminated, damage to the EL layer during film formation can be reduced. In particular, the argon gas used in forming the first conductive oxide film is It is preferable that the purity of the gas is high, for example, that the dew point is -70°C or less, preferably -100°C or less. It is preferable to use argon gas of this order.

[0191] The electrode provided on the opposite side to the light emitting side is made of a material having reflectivity to the light emitted from the EL layer 335. It is preferable to use a material that is

[0192] Examples of materials having light reflectivity include aluminum, gold, platinum, silver, nickel, and titanium. metals such as zinc, chromium, molybdenum, iron, cobalt, copper, or palladium, or Alloys containing these metals can be used. In addition, lanthanum and neodymium can be added to these metals or alloys. In addition, aluminum and titanium alloys, aluminum Aluminum-nickel alloys, aluminum-neodymium alloys, and other alloys containing aluminum Gold (aluminum alloy), silver and copper alloy, silver, palladium and copper alloy, silver and magnesium Silver-copper alloys, such as copper alloys, can also be used. Silver-copper alloys have high heat resistance, Further, a metal film or a metal oxide film may be laminated in contact with the aluminum alloy film. By so doing, it is possible to suppress the oxidation of the aluminum alloy film. Examples of the material include titanium and titanium oxide. For example, a film made of silver and an indium oxide film made of a metal material may be laminated. Uses laminated films of tin, silver-magnesium alloy and indium oxide-tin oxide, etc. It is possible.

[0193] Such electrodes are formed by deposition or sputtering. The shape is formed using a discharge method such as the inkjet method, a printing method such as the screen printing method, or a plating method. It can be achieved.

[0194] The EL layer 335 is a layer containing at least a light-emitting organic compound (hereinafter, also referred to as a light-emitting layer). It is sufficient that the layer is composed of a single layer, or a plurality of layers may be laminated. The structure is composed of, from the anode side, a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer. An example of the structure is a laminate of a layer, a light-emitting layer, and an electron injection layer. These layers do not necessarily have to be provided in the EL layer 335. Specifically, a plurality of light-emitting layers may be stacked in the EL layer 335. Alternatively, a hole injection layer may be provided on the electron injection layer. Other components such as an electronic relay layer can be added as appropriate. For example, two or more light-emitting layers having complementary colors may be laminated. By stacking these, white light can be emitted.

[0195] The EL layer 335 is formed by a vacuum deposition method or a discharge method such as an inkjet method or a dispense method. The insulating layer 11 can be formed by using a coating method such as spin coating.

[0196] [Adhesive layer, sealing layer] The adhesive layer and the sealing layer may be made of, for example, a resin that hardens at room temperature, such as a two-part mixed resin, or a thermosetting resin. For example, a curable material such as an epoxy resin or a photocurable resin, or a gel can be used. epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide, polyvinyl Chloride (PVC), Polyvinyl Butyral (PVB), Ethylene Vinyl Acetate (E In particular, materials with low moisture permeability such as epoxy resin are preferred. .

[0197] The adhesive layer and the sealing layer may contain a desiccant. For example, an alkaline earth metal acid Materials that absorb moisture by chemical adsorption, such as oxides (calcium oxide, barium oxide, etc.) Other drying agents such as zeolite and silica gel can be used. A substance that absorbs moisture by physical adsorption may be used. Also, a granular desiccant may be provided. As a result, the light emitted from the light emitting element 340 is diffused by the desiccant, resulting in high reliability. Moreover, a light emitting device (particularly useful for lighting applications) with improved viewing angle dependency can be realized.

[0198] [Color filter and black matrix] The color filter 321 is provided for the purpose of adjusting the color of light emitted from the light emitting element 340 and increasing the color purity. For example, in the case of forming a full-color display device using a white light emitting element, In this case, multiple pixels with different color filters are used. Alternatively, a three-color filter of green (G), blue (B), and yellow (Y) may be used. It is also possible to add four colors, R, G, B (and Y), and white (W). It is also possible to use pixels to provide four (or five) colors.

[0199] In addition, a black matrix 322 is provided between adjacent color filters 321. The black matrix 322 blocks the light from the light emitting element 340 of the adjacent pixel. The edge of the color filter 321 is cut by a black dot. By arranging it so as to overlap with the rack matrix 322, it is possible to suppress light leakage. The black matrix 322 is made of a material that blocks light emitted from the light emitting element 340. The insulating layer can be formed by using metal or organic resin containing a pigment. The block matrix 322 may be provided in an area other than the pixel area 103, such as the driving circuit 104. .

[0200] In addition, an overcoat is provided to cover the color filter 321 and the black matrix 322. The overcoat may be used to protect the color filter 321 and the black matrix 322. In addition to protecting the material, it also prevents impurities contained in the material from diffusing. The insulating film is made of a material that transmits light emitted from the element 340, and may be an inorganic insulating film or an organic insulating film. This can be done.

[0201] The above is a description of the materials and the forming method.

[0202] This embodiment may be implemented in appropriate combination with other embodiment modes described in this specification. This can be done.

[0203] (Embodiment 4) In this embodiment, examples of electronic devices including a display device according to one embodiment of the present invention will be described. .

[0204] The display device according to one embodiment of the present invention can have a curved display surface. Examples of electronic devices that can incorporate the present invention include television sets (televisions, television sets, etc.). (also called revision receivers), computer monitors, digital cameras, digital Video cameras, digital photo frames, mobile phones (also called mobile phones or mobile phone devices) ), portable game machines, personal digital assistants, audio playback devices, pachinko machines and other large game machines, etc. In addition, lighting and display devices can be installed on the interior and exterior walls of houses and buildings, and on the interior of automobiles. Alternatively, it may be possible to incorporate it along the curved surface of the exterior.

[0205] FIG. 11A shows an example of a mobile phone. A mobile phone 7400 includes a housing 740. In addition to the display unit 7402 incorporated in the 1, the operation buttons 7403, the external connection port 7404, The mobile phone 7400 is equipped with a speaker 7405, a microphone 7406, and the like. The display device according to one embodiment of the invention is used for the display portion 7402 .

[0206] In a mobile phone 7400 shown in FIG. 11A, when a display portion 7402 is touched with a finger or the like, You can also make calls, enter text, and perform any other functions. The operation can be performed by touching the display portion 7402 with a finger or the like.

[0207] In addition, by operating the operation button 7403, the power can be turned on and off, and the display unit 7402 can be displayed. For example, you can change the type of image displayed on the main menu from the email composition screen. You can switch to the menu screen.

[0208] Here, the display device of one embodiment of the present invention is incorporated in the display portion 7402. This makes it possible to display images along a curved display surface, and provides a highly reliable mobile phone. It is possible.

[0209] FIG. 11B shows an example of a wristband-type display device. 0 includes a housing 7101, a display unit 7102, an operation button 7103, and a transmitting / receiving device 7104. Prepare.

[0210] The portable display device 7100 can receive a video signal by a transmitting / receiving device 7104. The video signal can be displayed on the display unit 7102. Also, the audio signal can be transmitted to other receiving devices. It is also possible.

[0211] In addition, the operation button 7103 can be used to turn the power on and off and to switch the displayed image. You can also adjust the volume of the audio.

[0212] 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.

[0213] FIG. 11C shows an example of a wristwatch-type portable information terminal. The housing 7201, the display unit 7202, the band 7203, the buckle 7204, the operation button 7 205, an input / output terminal 7206, etc.

[0214] The portable information terminal 7200 is capable of carrying out mobile phone calls, e-mails, viewing and creating documents, playing music, and internet connections. It can run various applications such as internet communication and computer games. Cut.

[0215] The display unit 7202 has a curved display surface, and displays information along the curved display surface. The display unit 7202 is equipped with a touch sensor, and the screen can be operated by touching it with a finger or a stylus. For example, the icon 7 displayed on the display unit 7202 can be operated by touching the By touching 207, the application can be launched.

[0216] The operation button 7205 is used to set the time, turn the power on and off, and turn wireless communication on and off. It supports various functions such as auto-start, silent mode and power saving mode. For example, an operation system built into the portable information terminal 7200 can be The function of the operation button 7205 can also be freely set using the stem.

[0217] The portable information terminal 7200 is also capable of performing short-distance wireless communication. For example, To communicate hands-free by using a wireless headset It is also possible.

[0218] The portable information terminal 7200 also includes an input / output terminal 7206, and a connector for connecting to other information terminals. Data can be exchanged directly through the input / output terminal 7206. The charging operation can be performed by wireless power supply without going through the input / output terminal 7206. This is also possible.

[0219] The display device of one embodiment of the present invention is applied to the display portion 7202 of the portable information terminal 7200. can be done.

[0220] The display device of one embodiment of the present invention can be applied to the display portion of the electronic devices described in this embodiment. This allows for highly reliable, curved display and narrow-frame electronic devices. can.

[0221] This embodiment may be implemented in appropriate combination with other embodiment modes described in this specification. This can be done. [Explanation of symbols]

[0222] 100 display device 101 Substrate 102 Display section 103 Pixel section 104 Drive circuit 104a Drive circuit 104b Drive circuit 104c Drive circuit 104d Drive circuit 104e Drive circuit 104f Drive circuit 104g Drive circuit 104h Drive circuit 110 Curved section 111 Wiring 111a Wiring 111b wiring 112 Connection terminal 113 IC 114 Wiring 120 Curved section 121 First Part 122 Second Part 131 Substrate 132 Adhesive layer 133 ACF 134 Bump 135 Adhesive layer 141 Curved surface 142 Tangent line 143 Curvature direction 144 line 145 Surface to be formed 151 Wiring 201 Support substrate 202 Peeling layer 203 Peeling layer 211 Oxide layer 211a Oxide layer 211b Oxide layer 300 display device 311 Transistor 312 Transistor 313 Transistor 314 Transistor 316 Insulating Layer 317 Insulating Layer 318 Insulating layer 319 Insulating Layer 321 Color Filter 322 Black Matrix 333 Electrode 335 EL layer 337 Electrode 340 Light emitting element 341 Oxide layer 342 Adhesive layer 343 Peeling layer 350 Display device 352 Sealing layer 353 Substrate 354 Substrate 7100 Portable display devices 7101 Case 7102 Display section 7103 Operation button 7104 Transmitting and receiving equipment 7200 Portable Information Terminal 7201 Case 7202 Display section 7203 Band 7204 Buckle 7205 Operation button 7206 Input / output terminal 7207 Icon 7400 Mobile Phone 7401 Case 7402 Display section 7403 Operation button 7404 External connection port 7405 Speaker 7406 Mike

Claims

1. On a flexible substrate, A display unit; A plurality of connection terminals to which signals can be input from the outside; A plurality of wirings; the first connection terminal is electrically connected to the display unit by the first wiring; The wiring has a first portion branched into a plurality of wires and a second portion where the plurality of wires converge into one wire. Display device.

2. The first portion of the wiring has a region having a thickness thinner than that of the second portion. The display device according to claim 1 .

Images