Display element and display device

Abstract

The present invention reduces electric resistance of a connection part between a display element and a flexible substrate. A display element according to the present disclosure has a terminal and a void region. The terminal, which the display element according to the present disclosure has, is connected to an element in a display region, the element being disposed while being embedded in an insulating layer formed in an end part of a substrate on which the display region is disposed. The void region, which the display element according to the present disclosure has, is a region that becomes a void which, when a pad to be joined to the terminal in a flexible substrate provided with the pad is joined to the terminal, is formed between the pad and the insulating layer.

Description

Display element and display device

[0001] The present disclosure relates to a display element and a display device.

[0002] Display devices having display elements such as organic ELs are widely used. This display device includes a drive circuit for driving the display element. Usually, this drive circuit is arranged on a flexible substrate and directly connected to the display device. Specifically, terminals for signal transmission are arranged at the ends of the flexible substrate, and terminals are also arranged at the ends of the substrate of the display element. When the display element and the flexible substrate are connected, these terminals are electrically joined, enabling transmission of signals and the like between the display device and the drive circuit.

[0003] Display devices using an anisotropic conductive adhesive film (ACF: Anisotropic Conductive Film) for connecting such display elements and drive circuits have been proposed (see, for example, Patent Document 1). Here, the ACF is an adhesive film in which conductive particles are dispersed. The display element and the flexible substrate are adhered by this ACF. At this time, conductive particles are sandwiched between the terminals of the display element and the terminals of the flexible substrate, enabling an electrical connection to be obtained. In the above-described display device, a pad electrode layer constituting a terminal is arranged in a recess formed in the peripheral portion of the support substrate of the organic EL element. This pad electrode layer and the flexible substrate are connected via an ACF.

[0004] Japanese Patent Application Laid-Open No. 2015-028780

[0005] However, in the above prior art, there is a problem that the resistance of the connection portion between the display element and the flexible substrate is large. In the connection by ACF, since an electrical connection is obtained by fine conductive particles, a large connection area between the pads of the display element and the electrodes of the flexible substrate is required. Therefore, when the size of the terminal of the display element is reduced, the adhesion area by ACF also decreases, resulting in a problem that the resistance of the connection portion increases. This causes a problem of increased loss.

[0006] Therefore, the present disclosure proposes a display element and a display device that reduce the electrical resistance of the connection portion between the display element and the flexible substrate.

[0007] The display element according to this disclosure has a terminal connected to the element of the display area, which is embedded in an insulating layer formed at the edge of a substrate on which a display area is arranged, and a gap region which is a region that becomes an air gap formed between the pad and the insulating layer when the pad is joined to the terminal in a flexible substrate having a pad that is joined to the terminal.

[0008] This figure shows an example of the configuration of a display device according to an embodiment of this disclosure. This figure shows an example of the configuration of a display device according to an embodiment of this disclosure. This figure shows an example of the configuration of a display element according to an embodiment of this disclosure. This figure shows an example of the configuration of a flexible substrate according to an embodiment of this disclosure. This figure shows an example of the configuration of a display element according to a first embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of a display device according to a first embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a first embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a first embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a first embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a first embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a first embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a first embodiment of this disclosure. This figure shows another example of the configuration of a display element according to a first embodiment of this disclosure. This figure shows an example of the configuration of a display device according to a second embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a second embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a second embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a second embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a second embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a second embodiment of this disclosure. This figure shows an example of a method for manufacturing a display element according to a second embodiment of this disclosure. This is a diagram showing another example of a method for manufacturing a display element according to the second embodiment of this disclosure. This is a diagram showing another example of a method for manufacturing a display element according to the second embodiment of this disclosure. This is a diagram showing another example of a method for manufacturing a display element according to the second embodiment of this disclosure. This is a diagram showing another example of a method for manufacturing a display element according to the second embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of a display device according to the third embodiment of this disclosure. This is a diagram showing an example of a method for manufacturing a flexible substrate according to the third embodiment of this disclosure. This is a diagram showing an example of a method for manufacturing a flexible substrate according to the third embodiment of this disclosure. This is a diagram showing an example of a method for manufacturing a flexible substrate according to the third embodiment of this disclosure. This is a diagram showing another example of a method for manufacturing a flexible substrate according to the third embodiment of this disclosure.This is a diagram showing another example of a method for manufacturing a flexible substrate according to the third embodiment of this disclosure. This is a diagram showing another example of a method for manufacturing a flexible substrate according to the third embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of a display device according to the fourth embodiment of this disclosure. This is a diagram showing an example of the configuration of a flexible substrate according to the fifth embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of a display device according to the fifth embodiment of this disclosure. This is a diagram showing an example of the method for manufacturing a display device according to the fifth embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of a display device according to the sixth embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of a display device according to the seventh embodiment of this disclosure. This is a diagram showing an example of the method for manufacturing a display device according to the seventh embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of a display device according to the eighth embodiment of this disclosure. This is a diagram showing an example of the method for manufacturing a display device according to the eighth embodiment of this disclosure. This is a diagram showing an example of the method for manufacturing a display device according to the eighth embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of a display device according to the ninth embodiment of this disclosure. This is a diagram showing an example of the configuration of a flexible substrate according to the ninth embodiment of this disclosure. This is a diagram showing an example of the configuration of a flexible substrate according to the ninth embodiment of this disclosure. This is a diagram showing another example of a method for manufacturing a display device according to the ninth embodiment of this disclosure. This is a diagram showing an example of the configuration of a display device according to the tenth embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of a display device according to the tenth embodiment of this disclosure. This is a cross-sectional view showing another configuration example of the display device according to the tenth embodiment of the present disclosure. This is a diagram showing another configuration example of the display device according to the tenth embodiment of the present disclosure. This is a diagram showing another configuration example of the display device according to the tenth embodiment of the present disclosure. This is a diagram showing another configuration example of the display device according to the tenth embodiment of the present disclosure. This is a diagram showing another configuration example of the display device according to the tenth embodiment of the present disclosure. This is a diagram showing another configuration example of the display device according to the tenth embodiment of the present disclosure. This is a diagram showing another configuration example of the display device according to the tenth embodiment of the present disclosure. This is a cross-sectional view showing an example of the configuration example of the display device according to the eleventh embodiment of the present disclosure.This is a diagram showing another configuration example of the display device according to the 11th embodiment of this disclosure. This is a diagram showing another configuration example of the display device according to the 11th embodiment of this disclosure. This is a diagram showing another configuration example of the display device according to the 11th embodiment of this disclosure. This is a diagram showing another configuration example of the display device according to the 11th embodiment of this disclosure. This is a cross-sectional view showing an example of the configuration of the display area according to the embodiment of this disclosure.

[0009] The embodiments of this disclosure will be described in detail below with reference to the drawings. The description will be in the following order. In each of the following embodiments, the same parts will be denoted by the same reference numerals, and redundant descriptions will be omitted. 1. First Embodiment 2. Second Embodiment 3. Third Embodiment 4. Fourth Embodiment 5. Fifth Embodiment 6. Sixth Embodiment 7. Seventh Embodiment 8. Eighth Embodiment 9. Ninth Embodiment 10. Tenth Embodiment 11. Eleventh Embodiment 12. Display Area Configuration

[0010] (1. First Embodiment) <Configuration of Display Device> Figures 1A and 1B are diagrams showing an example configuration of a display device according to the present disclosure. Figures 1A and 1B are diagrams showing an example configuration of the display device 10. Figure 1A is a plan view showing an example configuration of the display device 10. Figure 1B is a schematic cross-sectional view showing an example configuration of the display device 10.

[0011] The display device 10 comprises a display element 100 and a flexible substrate 200. The display element 100 is constructed by arranging a display area 160 on a substrate (substrate 110, described later). Multiple terminals for signal transmission are arranged at the edges of the substrate of the display element 100.

[0012] The flexible substrate 200 is a substrate equipped with a circuit for transmitting signals to the display element 100. For example, a drive circuit for driving the display element 100 is mounted on the flexible substrate 200. Multiple terminals (pads) for signal transmission are arranged on a part of the end of the flexible substrate 200. These pads of the flexible substrate 200 are joined to the terminals of the display element 100. The lower end of the display element 100 in Figure 1A and the upper end of the flexible substrate 200 in Figure 1A are joined. Adhesive 180 is placed near this joint to reinforce the connection.

[0013] Figure 2A is a diagram showing an example configuration of a display element according to the present disclosure. The same figure is a plan view showing an example configuration of the display element 100. A plurality of terminals 140 are arranged at the end of the substrate of the display element 100. These terminals 140 are connected to elements of the display area 160 via wiring (not shown).

[0014] Figure 2B is a diagram showing an example configuration of a flexible substrate according to the present disclosure. This figure is a plan view showing an example configuration of the flexible substrate 200. The flexible substrate 200 comprises a plurality of pads 240, a plurality of wirings 232, and a drive circuit 260. The pads 240 are electrodes for transmitting signals. When the flexible substrate 200 is connected to the display element 100, these pads 240 are connected to the terminals 140 of the display element 100. The pads 240 are connected to the drive circuit 260 by the wirings 232. The flexible substrate 200 also comprises a substrate 210, which will be described later.

[0015] The drive circuit 260 drives the display element 100. This drive circuit 260 generates control signals for the display element 100. The generated signals are transmitted to the terminal 140 of the display element 100 via the pad 240.

[0016] Figure 3 is a diagram showing an example of the configuration of a display element according to the first embodiment of this disclosure. The figure is a plan view showing an example of the configuration of the region where the terminal 140 of the display element 100 is arranged. As shown in the figure, the terminal 140 is arranged in a region adjacent to the display region 160 at the edge of the substrate of the display element 100. The terminal 140 is also arranged embedded in an insulating layer 131 formed on the surface of a substrate 110 (not shown). A gap region 150 is formed adjacent to the terminal 140. The area with dot hatching in the figure represents the gap region 150. This gap region 150 is the region that becomes the gap between the pad 240 and the insulating layer 131 when the pad 240 of the flexible substrate 200 is joined to the terminal 140. The gap region 150 in the figure shows an example in which it is formed in a part of the insulating layer 131 adjacent to the terminal 140.

[0017] Figure 4 is a cross-sectional view showing an example configuration of a display device according to the first embodiment of this disclosure. The same figure is a schematic cross-sectional view showing an example configuration of the display device 10. The display device 10 comprises a display element 100 and a flexible substrate 200. As described above, the flexible substrate 200 is connected to the display element 100. Note that the adhesive 180 shown in Figure 1B is omitted in the display device 10 shown in Figure 4.

[0018] The display element 100 in Figure 4 comprises a substrate 110, an insulating layer 131, a display area 160, and terminals 140. The substrate 110 supports the display area 160, etc. For example, a glass plate can be used for this substrate 110. The insulating layer 131 is disposed on the surface of the substrate 110 and insulates the optical elements and terminals 140 of the display area 160. For example, silicon dioxide (SiO₂) is used for this insulating layer 131. ２ ) can be applied.

[0019] The display area 160 is the area where the optical elements for display are arranged. Multiple pixels 120 are arranged in a two-dimensional matrix shape in the display area 160. The pixels 120 emit light in response to the input signal. An insulating film 161, sealing portions 162 and 163, and a transparent substrate 164 are arranged in the display area 160. The insulating film 161 insulates the display elements 100. This insulating film 161 contains, for example, SiO ２ The following can be used. The sealing portion 162 seals the pixel 120. The sealing portion 163 seals the pixel 120 and also adheres the transparent substrate 164. Resin can be used for the sealing portions 162 and 163. The transparent substrate 164 protects the pixel 120, etc. For example, a resin substrate can be used for this transparent substrate 164. Details of the configuration of the display area 160 will be described later.

[0020] Terminal 140 is an electrode for transmitting signals from pixels 120 and the like. Terminal 140 can be made of a metal such as aluminum (Al). Terminal 140 is embedded in the insulating layer 131. Terminal 140 is connected to the elements of pixels 120 in the display area 160 by wiring (not shown).

[0021] The flexible substrate 200 comprises a substrate 210 and pads 240. The substrate 210 is made of a flexible film and supports the pads 240 and the conductive layers of wiring 232 (not shown). For example, a polyimide film can be used for the substrate 210.

[0022] The pad 240 is an electrode for transmitting signals. This pad 240 can be made of, for example, a metal. For example, the pad 240 can be made of copper (Cu) with gold (Au) placed on its surface.

[0023] The display element 100 and the flexible substrate 200 can be connected as follows. First, the flexible substrate 200 is placed on top of the end of the display element 100 while aligning the terminals 140 of the display element 100 and the pads 240 of the flexible substrate 200. Next, the pads 240 are pressed against the terminals 140 using a bonding head that is in contact with the substrate 210 side of the flexible substrate 200 while applying ultrasonic waves. This joins the pads 240 and the terminals 140. The display element 100 and the flexible substrate 200 can then be connected.

[0024] Figure 4 shows the state in which the flexible substrate 200 is connected to the display element 100. A gap region 150 is positioned adjacent to the terminal 140. The gap region 150 in Figure 4 is formed by a recess formed in the insulating layer 131 of the display element 100. As mentioned above, the terminal 140 is embedded in the insulating layer 131. If the upper surface of the insulating layer 131 at the position overlapping the pad 240 is higher than the upper surface of the terminal 140, a gap will be created between the terminal 140 and the pad 240, which will hinder bonding.

[0025] Therefore, a gap is provided between the insulating layer 131 and the pad 240 in the area in question. In the display device 10 of Figure 4, a recess is formed in advance on the surface of the insulating layer 131 of the display element 100. This recess forms a gap between the insulating layer 131 and the pad 240 when the flexible substrate 200 is connected to the display element 100. This gap eliminates interference from the insulating layer 131, allowing the terminal 140 and the pad 240 to be brought into close contact during joining. This makes it possible to reduce the resistance of the connection between the terminal 140 and the pad 240. Furthermore, it is possible to improve the connection strength between the terminal 140 and the pad 240.

[0026] Thus, the void region 150 is the area that becomes a void when the display element 100 and the flexible substrate 200 are joined together. The void region 150 in Figure 4 shows an example where it is formed on the side of the insulating layer 131 of the display element 100.

[0027] <Method for Manufacturing a Display Element> Figures 5A-5F show an example of a method for manufacturing a display element according to the first embodiment of the present disclosure. Figures 5A-5F show an example of a method for manufacturing a display element 100. First, an insulating layer 132 is placed on the substrate 110. Next, terminals 140 are formed on the surface of the insulating layer 132 (Figure 5A).

[0028] Next, an insulating layer 131 shaped to cover the terminal 140 is placed on the surface of the insulating layer 132, and the surface is flattened (Figure 5B).

[0029] Next, an insulating film 161 is placed on the surface of the insulating layer 131 (Figure 5C). Then, a resist 400 is placed on the surface of the insulating film 161. An opening 401 is formed in the resist 400 in the region of the terminal 140 (Figure 5D).

[0030] Next, the insulating film 161 is etched using the resist 400 as a mask. Furthermore, the insulating layer 131 is etched to expose the surface of the terminal 140 (Figure 5E).

[0031] Next, a void region 150 is formed. This can be done by selectively etching the insulating layer 131 in that region (Figure 5F).

[0032] <Other Configurations of the Display Element> Figure 6 is a diagram showing another configuration example of the display element according to the first embodiment of the present disclosure. This diagram, like Figure 3, shows an example configuration of the display element 100. The display element 100 in this figure differs from the display element 100 in Figure 3 in that a gap region 150 with a shape surrounding the terminal 140 is arranged therein. The gap region 150 in this figure is formed by a recess formed in the insulating layer 131 around the terminal 140. While the gap region 150 in Figure 3 is arranged in a part of the area adjacent to the terminal 140, the gap region 150 in this figure is arranged around the terminal 140, including the area directly below the pad 240.

[0033] Note that the configuration of the display device 10 is not limited to this example. For example, the adhesive portion 170, which will be described later, can also be arranged in Figure 15.

[0034] As described above, the display device 10 of the first embodiment of this disclosure has a gap region 150 arranged on the display element 100. This gap region 150 prevents interference of the insulating layer 131 adjacent to the terminal 140 when the pad 240 of the flexible substrate 200 is joined to the terminal 140 of the display element 100. As a result, the terminal 140 and the pad 240 can be brought into close contact, and the electrical resistance of the connection between the terminal 140 and the pad 240 can be reduced. This reduces signal transmission loss between the display element 100 and the flexible substrate 200. Furthermore, the connection strength of the terminal 140 and the pad 240 can be improved, and the connection strength of the display element 100 and the flexible substrate 200 can be improved.

[0035] (2. Second Embodiment) The display device 10 of the first embodiment described above used a recess formed in the insulating layer 131 of the display element 100 as a void region 150. In contrast, the display device 10 of the second embodiment of this disclosure differs from the first embodiment described above in that it forms the void region 150 with a terminal (terminal 142) made of a thick film.

[0036] <Configuration of the Display Device> Figure 7 is a diagram showing an example configuration of a display device according to the second embodiment of the present disclosure. This figure is a schematic cross-sectional view showing an example configuration of the display device 10, similar to Figure 4. The display device 10 in this figure differs from the display device 10 in Figure 4 in that it has terminal 142 instead of terminal 140.

[0037] Terminal 142 is made of a thicker film than terminal 140, and its upper surface is positioned higher than the upper surfaces of the insulating layer 131 and the insulating film 161. In other words, terminal 142 is configured to protrude from the surface of the insulating film 161. The conductor layer (conductor layer 141) of terminal 142, which protrudes from the surface of the insulating film 161, forms a void region 150.

[0038] <Method for Manufacturing a Display Element> Figures 8A-8F are diagrams showing an example of a method for manufacturing a display element according to the second embodiment of the present disclosure. Figures 8A-8F are diagrams showing an example of a method for manufacturing a display element 100. First, the process shown in Figure 5A-5C is performed. Next, a resist 402 is placed on the surface of the insulating film 161. An opening 403 is formed in the region of the terminal 142 in the resist 402 (Figure 8A).

[0039] Next, the insulating film 161 and the insulating layer 131 are etched using the resist 402 as a mask to expose the surface of the terminal 140 (Figure 8B). Then, the resist 402 is removed (Figure 8C).

[0040] Next, a resist 404 is placed on the surface of the insulating film 161. An opening 405 is formed in the resist 404 at the position of the terminal 140 (Figure 8D).

[0041] Next, a material film 406 for the terminal 140 is placed on the surface of the substrate 110 containing the resist 404 (Figure 8E). This forms the conductive layer 141.

[0042] Next, the resist 404 and any unnecessary material film 406 are removed. This forms the terminal 142 (Figure 8F).

[0043] Figures 9A-9D illustrate another example of a method for manufacturing a display element according to the second embodiment of this disclosure. Figures 9A-9D illustrate another example of a method for manufacturing the display element 100.

[0044] First, perform the steps of FIGS. 8A - 8C. Next, dispose the material film 407 of the terminal 140 on the surface of the substrate 110 (FIG. 9A).

[0045] Next, planarize the surface of the material film 407 (FIG. 9B). This can be performed, for example, by chemical mechanical polishing (CMP: Chemical Mechanical Polishing).

[0046] Next, dispose a resist 408 on the surface of the material film 407. An opening 409 is formed in a region of the resist 408 other than the region overlapping with the terminal 140 (FIG. 9C).

[0047] Next, use the resist 408 as a mask to etch the material film 407 to form the conductor layer 141 (FIG. 9D). Thereafter, remove the resist 408. Thereby, the terminal 142 can be formed.

[0048] Since the configuration of the display device 10 other than that described above is the same as the configuration of the display device 10 in the first embodiment of the present disclosure, the description thereof is omitted.

[0049] Thus, the display device 10 of the second embodiment of the present disclosure includes a void region 150 formed by the conductor layer 141 protruding from the surface of the insulating film 161 in the terminal 142. Thereby, the terminal 140 and the pad 240 can be brought into close contact, and the electrical resistance of the connection portion between the terminal 140 and the pad 240 can be reduced.

[0050] (3. Third Embodiment) In the display device 10 of the first embodiment described above, the void region 150 was disposed in the display element 100. In contrast, the display device 10 of the third embodiment of the present disclosure is different from the first embodiment described above in that a void region (void region 151) is disposed in the flexible substrate 200.

[0051] <Configuration of Display Device> FIG. 10 is a cross-sectional view showing a configuration example of a display device according to the third embodiment of the present disclosure. Similar to FIG. 4, this figure is a schematic cross-sectional view showing a configuration example of the display device 10. The display device 10 in this figure is different from the display device 10 in FIG. 4 in that a void region (void region 151) is disposed in the pad (pad 241) of the flexible substrate 200.

[0052] The flexible substrate 200 in Figure 10 includes a pad 241. A protrusion 242 is provided on this pad 241. This protrusion 242 can be made of the same material as the pad 241, for example. The portion of this protrusion 242 is joined to the terminal 140. The protrusion 242 separates the pad 241 from the insulating layer 131 during joining, creating a gap. The area of ​​the pad 241 adjacent to this protrusion 242 acts as a recess. That is, the gap area 151 in Figure 10 is formed by the protrusion 242.

[0053] <Method for Manufacturing a Flexible Substrate> Figures 11A-11C are diagrams showing an example of a method for manufacturing a flexible substrate according to the third embodiment of the present disclosure. Figures 11A-11C are diagrams showing an example of a method for manufacturing a flexible substrate 200.

[0054] First, a material film 410 for the pad 241 is placed on the substrate 210 (Figure 11A). Next, a resist 411 is placed on the material film 410. This resist 411 is configured in the shape of the protrusion 242. Next, the material film 410 is etched using the resist 411 as a mask to form the protrusion 242 and the pad 241 (Figure 11C).

[0055] <Other Methods for Manufacturing Flexible Substrates> Figures 12A-12C illustrate other examples of methods for manufacturing a flexible substrate according to the third embodiment of this disclosure. Figures 12A-12C illustrate an example of a method for manufacturing a flexible substrate 200.

[0056] First, a pad 243 is placed on the substrate 210 (Figure 12A). Next, a resist 413 is placed on the surface of the pad 243. This resist 413 is formed in areas other than the protrusion 242 (Figure 12B). Next, the protrusion 242 is formed on the upper layer of the pad 243 (Figure 12C). This can be done, for example, by forming a metal layer on the surface of the pad 243 by plating. The resist 413 is used as a plating resist. In this way, the protrusion 242 can be formed by a conductive layer such as metal laminated on the surface of the pad 243. This allows the pad 241 to be formed.

[0057] The configuration of the display device 10 other than that described above is the same as that of the display device 10 in the first embodiment of this disclosure, so a description will be omitted.

[0058] Thus, the display device 10 of the third embodiment of this disclosure includes a gap region 151 located on the side of the flexible substrate 200. This makes it possible to reduce the electrical resistance of the connection portion between the terminal 140 and the pad 240.

[0059] (4. Fourth Embodiment) The display device 10 of the third embodiment described above had a protrusion 242 formed on the pad 241. In contrast, the display device 10 of the fourth embodiment of the present disclosure differs from the third embodiment described above in that it forms the protrusion 242 by a step in the flexible substrate 200.

[0060] <Configuration of the display device> Figure 13 is a cross-sectional view showing an example of the configuration of a display device according to the fourth embodiment of the present disclosure. This figure is a schematic cross-sectional view showing an example of the configuration of the display device 10, similar to Figure 10. The display device 10 in this figure differs from the display device 10 in that a protrusion 242 is formed by a step formed on the flexible substrate 200.

[0061] As described above, a step 244 is formed on the flexible substrate 200 in Figure 13. This step 244 can be formed by bending the flexible substrate 200. The bending of the flexible substrate 200 can be done, for example, by using a mold. Similar to the display device 10 in Figure 10, the void region 151 is formed by the protrusion 242.

[0062] The configuration of the display device 10 other than that described above is the same as that of the display device 10 in the third embodiment of this disclosure, so a description will be omitted.

[0063] Thus, in the fourth embodiment of the present disclosure, the display device 10 forms a protrusion 242 by a step in the flexible substrate 200. This simplifies the manufacturing process of the protrusion 242.

[0064] (5. Fifth Embodiment) In the above-described prior art, when the size of the terminals of the display element is reduced, the bonding area by ACF also decreases, which is a problem as the connection strength decreases.

[0065] Therefore, in the fifth embodiment of this disclosure, we propose a display element and a display device that improve the connection strength between the display element and the flexible substrate.

[0066] Furthermore, in the first embodiment of the display device 10 described above, when connecting the flexible substrate 200 to the display element 100, the bonding head was applied via the substrate 210 of the flexible substrate 200. In contrast, the display device 10 of the fifth embodiment of this disclosure differs from the first embodiment described above in that an opening is formed in the substrate 210, and the bonding head is brought into direct contact with the back surface of the pad 240 to perform bonding.

[0067] <Configuration of Flexible Substrate> Figure 14 is a diagram showing an example configuration of a flexible substrate according to the fifth embodiment of the present disclosure. This figure is a plan view showing an example configuration of the flexible substrate 200, similar to Figure 2B. The flexible substrate 200 in this figure differs from the flexible substrate 200 in Figure 2B in that an opening 211 is formed in the substrate 210. Note that the drive circuit 260 and wiring 232 are omitted in this figure.

[0068] The opening 211 is formed in the substrate 210 at a position overlapping with the pad 240. The opening 211 can be configured to have a width of, for example, 750 μm. This opening 211 can be formed, for example, by etching the substrate 210 after the pad 240 has been placed.

[0069] <Configuration of the display device> Figure 15 is a cross-sectional view showing an example of the configuration of a display device according to the fifth embodiment of the present disclosure. This figure is a schematic cross-sectional view showing an example of the configuration of the display device 10, similar to Figure 4. The display device 10 in this figure differs from the display device 10 in Figure 4 in that an opening 211 is formed in the flexible substrate 200 and an adhesive portion 170 is further arranged.

[0070] The adhesive portion 170 is used to bond the substrate 110 and the flexible substrate 200 of the display element 100. This adhesive portion 170 is placed between the substrate 110 and the flexible substrate 200 after the terminals 140 and pads 240 have been bonded. For example, a liquid curable resin used as an underfill material in flip-chip mounting can be applied to the adhesive portion 170. As will be described later, the adhesive portion 170 can be placed through an opening 211.

[0071] <Method for Manufacturing a Display Device> Figures 16A and 16B are diagrams showing an example of a method for manufacturing a display device according to the fifth embodiment of this disclosure. Figures 16A and 16B are diagrams showing an example of a method for manufacturing a display device 10.

[0072] First, the end of the flexible substrate 200 is placed on the end of the display element 100 while aligning the terminals 140 of the display element 100 and the pads 240 of the flexible substrate 200. Next, the bonding head 300 is brought into contact with the back surface of the pads 240 through the opening 211, and the pads 240 are pressed against the terminals 140 while applying ultrasonic waves (Figure 16A). This bonds the pads 240 to the terminals 140.

[0073] Next, the adhesive portion 170 is placed at the connection point between the display element 100 and the flexible substrate 200. This can be done by applying the liquid curable resin that constitutes the adhesive portion 170 using the dispenser 301 (Figure 16B). As shown in Figure 16B, the liquid curable resin can be applied through the opening 211. After that, the liquid curable resin is cured to form the adhesive portion 170.

[0074] By placing an opening 211 in the substrate 210 of the flexible substrate 200, ultrasonic waves from the bonding head 300 can be transmitted to the pad 240 without going through the substrate 210. This improves the transmission efficiency of ultrasonic waves and thus improves the bonding strength. Furthermore, in the display device 10 of this disclosure, it is possible to apply the liquid curable resin constituting the adhesive portion 170 through the opening 211. Since it is not necessary to invert the display device 10 in order to apply the liquid curable resin, the manufacturing process can be simplified. In addition, visual inspection of the bonded portion through the opening 211 becomes possible, which improves the quality of the display device 10.

[0075] The configuration of the display device 10 other than that described above is the same as that of the display device 10 in the first embodiment of this disclosure, so a description will be omitted.

[0076] Thus, the display device 10 of the fifth embodiment of this disclosure can improve the connection strength of the terminals 140 and pads 240 by using a flexible substrate 200 having an opening 211. This improves the connection strength of the display element 100 and the flexible substrate 200.

[0077] (6. Sixth Embodiment) The display device 10 of the fifth embodiment described above had terminals 140 and pads 240 joined together. In contrast, the display device 10 of the sixth embodiment of this disclosure differs from the fifth embodiment described above in that it joins bumps 149 located on terminals 140 with pads 240.

[0078] <Configuration of the display device> Figure 17 is a cross-sectional view showing an example configuration of a display device according to the sixth embodiment of the present disclosure. This figure is a schematic cross-sectional view showing an example configuration of the display device 10, similar to Figure 15. The display device 10 in this figure differs from the display device 10 in Figure 15 in that a bump 149 is arranged on the terminal 140.

[0079] In the display device 10 of Figure 17, the bump 149 and the pad 240 are joined together. This joining can be performed using the bonding head 300 shown in Figure 16A. For example, a stud bump can be used for the bump 149. The bump 149 can also be made of Au. The height of the bump 149 after joining can be, for example, 10 to 20 μm. The adhesive portion 170 can be arranged in the same manner as in Figure 16B.

[0080] The configuration of the display device 10 other than that described above is the same as that of the display device 10 in the fifth embodiment of this disclosure, so a description will be omitted.

[0081] Thus, even when a bump 149 is positioned on the terminal 140, the display device 10 of the sixth embodiment of this disclosure can bring the bonding head 300 into contact with the pad 240 through the opening 211 and bond with the bump 149. Furthermore, the liquid curable resin constituting the adhesive portion 170 can be introduced through the opening 211.

[0082] (7. Seventh Embodiment) In the above-described conventional technology, when the size of the terminals of the display element is reduced, the bonding area by ACF also decreases, which is a problem as the connection strength decreases.

[0083] Therefore, in the seventh embodiment of this disclosure, we propose a display element and a display device that improve the connection strength between the display element and the flexible substrate.

[0084] Furthermore, in the first embodiment of the display device 10 described above, the terminal 140 of the display element 100 and the pad 240 of the flexible substrate 200 were joined together. In contrast, the seventh embodiment of the display device 10 of this disclosure differs from the first embodiment described above in that it joins the bump 149 located on the terminal 140 to the pad 240.

[0085] <Configuration of the display device> Figure 18 is a cross-sectional view showing an example configuration of a display device according to the seventh embodiment of the present disclosure. This figure is a schematic cross-sectional view showing an example configuration of the display device 10, similar to Figure 4. The display device 10 in this figure differs from the display device 10 in that a bump 149 is arranged on the terminal 140 of the display element 100, and an adhesive portion 250 is arranged between the display element 100 and the flexible substrate 200.

[0086] Similar to the display device 10 in Figure 17, the bumps 149 and pads 240 are joined together. An adhesive portion 250 is positioned near the bumps 149. This adhesive portion 250 attaches the flexible substrate 200 to the substrate 110. In Figure 18, the adhesive portion 250 attaches the flexible substrate 200 to the surfaces of the insulating layer 131 and terminals 140 placed on the substrate 110. The adhesive portion 250 can be made of, for example, an adhesive film (e.g., a die attach film (DAF)).

[0087] <Method for Manufacturing a Display Device> Figure 19 is a diagram showing an example of a method for manufacturing a display device according to the seventh embodiment of this disclosure. The same figure shows an example of a method for manufacturing the display device 10.

[0088] First, the adhesive portion 250 is attached to the flexible substrate 200. Next, the end of the flexible substrate 200 is placed on the end of the display element 100 while aligning the terminals 140 of the display element 100 and the pads 240 of the flexible substrate 200. Next, the bonding head 300 is brought into contact with the back surface of the flexible substrate 200, and the pads 240 are pressed against the terminals 140 while applying ultrasonic waves. As a result, the heads of the bumps 149 penetrate the adhesive portion 250 and come into contact with the surface of the pads 240, thus bonding them together. It is preferable to heat the adhesive portion 250 to about 70°C during bonding. This is because the viscosity of the adhesive portion 250 decreases, making it easier to bond the bumps 149 and the pads 240. Furthermore, applying heat can also improve the strength of the bond (metal-to-metal bonding) between the bumps 149 and the pads 240.

[0089] The height of the bump 149 before bonding can be, for example, 25 μm. In this case, the adhesive portion 250 can be, for example, 20 μm thick. That is, the adhesive portion 250 can be configured to have a thickness smaller than the height of the bump 149 before bonding.

[0090] By placing the adhesive portion 250 between the substrate 110 and the flexible substrate 200, the connection strength between the substrate 110 and the flexible substrate 200 can be improved. This makes it possible to omit the adhesive portion 170 shown in Figures 15 and 17.

[0091] The configuration of the display device 10 other than that described above is the same as that of the display device 10 in the first embodiment of this disclosure, so a description will be omitted.

[0092] Thus, the display device 10 of the seventh embodiment of this disclosure can improve the connection strength between the substrate 110 and the flexible substrate 200 by arranging the adhesive portion 250 between the substrate 110 and the flexible substrate 200. Therefore, the connection strength between the display element 100 and the flexible substrate 200 can be improved.

[0093] (8. Eighth Embodiment) In the seventh embodiment of the display device 10 described above, the adhesive portion 250 was arranged in the area of ​​the pad 240 of the flexible substrate 200. In contrast, the eighth embodiment of the display device 10 of the present disclosure differs from the seventh embodiment in that a gap is formed between the pad 240 and the adhesive portion 250.

[0094] <Configuration of the Display Device> Figure 20 is a cross-sectional view showing an example configuration of a display device according to the eighth embodiment of the present disclosure. This figure is a schematic cross-sectional view showing an example configuration of the display device 10, similar to Figure 18. The display device 10 in this figure differs from the display device 10 in Figure 18 in that gap-forming portions 258 and 259 for forming a gap between the pad 240 and the adhesive portion 250 before the bump 149 is bonded to the pad 240 are arranged on the flexible substrate 200. For example, a resist film attached to the flexible substrate 200 can be used for the gap-forming portions 258 and 259.

[0095] <Method for Manufacturing a Display Device> Figures 21A and 21B are diagrams showing an example of a method for manufacturing a display device according to the eighth embodiment of the present disclosure. Figures 21A and 21B are diagrams showing an example of a method for manufacturing a display device 10.

[0096] Figure 21A shows the display element 100 and flexible substrate 200 before connection. Bumps 149 are placed on the terminals 140 of the display element 100. These bumps 149 can be configured to have a height of, for example, 25 μm.

[0097] Furthermore, gap-forming portions 258 and 259 and an adhesive portion 250 are arranged on the flexible substrate 200. Since the gap-forming portions 258 and 259 are arranged between the flexible substrate 200 and the adhesive portion 250, a gap 257 is formed in the region between the gap-forming portions 258 and 259.

[0098] Figure 21B shows the process of connecting the flexible substrate 200 to the display element 100. The flexible substrate 200 is pressed against the display element 100 using a bonding head 300 (not shown). At this time, the heads of the bumps 149 that have penetrated the adhesive portion 250 come into contact with the pad 240 in the region of the gap 257. Subsequently, the heads of the pad 240 are crushed by the pressure, and the bumps 149 are joined to the pad 240. Because the heads of the bumps 149 come into contact with the pad 240 in the region of the gap 257, the amount of adhesive portion 250 trapped between the bumps 149 and the pad 240 can be reduced. This improves the connection strength between the bumps 149 and the pad 240.

[0099] Note that either the gap-forming portion 258 or 259 can be omitted.

[0100] The configuration of the display device 10 other than that described above is the same as that of the display device 10 in the seventh embodiment of this disclosure, so a description will be omitted.

[0101] Thus, the display device 10 of the eighth embodiment of this disclosure can form a gap between the pad 240 and the adhesive portion 250 before the bump 149 is joined by gap-forming portions 258 and 259 arranged on the flexible substrate 200. This improves the connection strength between the bump 149 and the pad 240.

[0102] (9. Ninth Embodiment) In the seventh embodiment of the display device 10 described above, the adhesive portion 250 was arranged in the area of ​​the pad 240 of the flexible substrate 200. In contrast, the ninth embodiment of the display device 10 of the present disclosure differs from the seventh embodiment described above in that an opening (opening 211) is formed in the adhesive portion 250.

[0103] <Configuration of the display device> Figure 22 is a cross-sectional view showing an example configuration of a display device according to the ninth embodiment of the present disclosure. This figure is a schematic cross-sectional view showing an example configuration of the display device 10, similar to Figure 18. The display device 10 in this figure differs from the display device 10 in Figure 18 in that an opening 251 is formed in the adhesive portion 250. The opening 251 can be positioned at the location of the bump 149 in the adhesive portion 250.

[0104] The opening 251 of the adhesive portion 250 allows the bump 149 to pass through when the bump 149 and the pad 240 are joined together.

[0105] <Method for Manufacturing a Display Device> Figure 23 is a diagram showing an example of a method for manufacturing a display device according to the ninth embodiment of this disclosure. The same figure shows an example of a method for manufacturing the display device 10.

[0106] The bump 149 can have a bottom width of, for example, 60 μm. In this case, the opening 251 of the adhesive portion 250 can be configured to have a width of 50 μm. That is, the opening 251 of the adhesive portion 250 can be configured to have a width narrower than the width of the bump 149. Since the head of the bump 149 abuts against the pad 240 in the region of the opening 251, the amount of adhesive portion 250 trapped between the bump 149 and the pad 240 can be reduced. This improves the connection strength between the bump 149 and the pad 240.

[0107] <Configuration of Flexible Substrate> Figures 24A and 24B show examples of the configuration of a flexible substrate according to the ninth embodiment of the present disclosure. Figures 24A and 24B are plan views showing examples of the configuration of a flexible substrate 200. In addition, adhesive parts (adhesive parts 250, etc.) are shown on the flexible substrate 200 in Figures 24A and 24B.

[0108] Figure 24A shows an example of an adhesive portion 250 in which a circular opening 251 is located. Figure 24B shows an example of an opening 251 formed by the region between two adhesive portions (adhesive portions 252 and 253).

[0109] <Other Methods for Manufacturing Display Devices> Figure 25 shows another example of a method for manufacturing a display device according to the ninth embodiment of this disclosure. This figure, like Figure 23, shows an example of a method for manufacturing the display device 10. The display device 10 in this figure differs from the display device 10 in Figure 23 in that the adhesive portion 250 is located on the side of the display element 100.

[0110] The configuration of the display device 10 other than that described above is the same as that of the display device 10 in the seventh embodiment of this disclosure, so a description will be omitted.

[0111] Thus, in the ninth embodiment of the present disclosure, the display device 10 has an opening 251 in the adhesive portion 250. This improves the connection strength between the bump 149 and the pad 240.

[0112] (10. Tenth Embodiment) In the above-described prior art, when the size of the terminals of the display element is reduced, the bonding area by ACF also decreases, which is a problem as the connection strength decreases.

[0113] Therefore, in the tenth embodiment of this disclosure, we propose a display element and a display device that improve the connection strength between the display element and the flexible substrate.

[0114] Furthermore, in the first embodiment of the display device 10 described above, the terminals 140 of the display element 100 and the pads 240 of the flexible substrate 200 were joined together. In contrast, the tenth embodiment of the display device 10 of this disclosure differs from the first embodiment described above in that it joins the bumps 149 arranged on the terminals 140 to the pads 240.

[0115] <Configuration of the Display Device> Figure 26 is a diagram showing an example configuration of a display device according to the tenth embodiment of the present disclosure. Similar to Figure 3, this figure is a plan view showing an example configuration of the display element 100 within the display device 10. The display element 100 in this figure differs from the display element 100 in Figure 3 in that a bump 149 is arranged on the terminal 140, and an adhesive portion 255 is further arranged near the bump 149. The adhesive portion 255 is an example of the "second adhesive portion" of the present disclosure.

[0116] In Figure 26, the white circles represent bumps 149, and the dotted hatched circles represent adhesive portions 255. These adhesive portions 255 are positioned on the surface of the substrate 110 near the bumps 149 and bond the substrate 110 and the flexible substrate 200 when the terminals 140 and pads 240 are joined. The adhesive portions 255 are configured in an island-like shape in a plan view. The display element 100 in Figure 26 shows an example where an adhesive portion 255 is placed for each terminal 140, and the terminals 140 and adhesive portions 255 are arranged alternately. In addition, in the display element 100 of Figure 26, multiple adhesive portions 255 are arranged discretely. The dotted lines in Figure 26 represent the flexible substrate 200 and pads 240.

[0117] Figure 27 is a cross-sectional view showing an example configuration of a display device according to the tenth embodiment of the present disclosure. This figure, like Figure 4, is a schematic cross-sectional view showing an example configuration of the display device 10. As described above, the adhesive portion 255 is arranged near the bump 149.

[0118] The adhesive portion 255 can be made of resin. This resin can be a thermoplastic resin such as acrylic resin or a thermosetting resin such as epoxy resin. The adhesive portion 255 is placed on the display element 100 before the flexible substrate 200 is connected. The adhesive portion 255 can be placed by application using a dispenser. Alternatively, the adhesive portion 255 can be placed by screen printing. By placing the adhesive portion 255, the connection between the bump 149 and the pad 240 can be reinforced.

[0119] Figure 28 is a cross-sectional view showing another configuration example of a display device according to the tenth embodiment of the present disclosure. This figure, like Figure 27, is a schematic cross-sectional view showing an example of the configuration of the display device 10. The display device 10 in this figure differs from the display device 10 in Figure 27 in that the adhesive portion 255 adheres to the substrate 210 of the flexible substrate 200. While the adhesive portion 255 in Figure 27 adheres to the pad 240, which is an inorganic material, the adhesive portion 255 in this figure adheres to the substrate 210, which is an organic material, thus improving the adhesive strength.

[0120] Figures 29A and 29G show another example configuration of the display device according to the tenth embodiment of this disclosure. The variations of the adhesive portion 255 will be illustrated using Figures 29A and 29G.

[0121] Figure 29A shows an example of an adhesive portion 255 configured in an elliptical shape. Figure 29B shows an example of an adhesive portion 255 positioned adjacent to a bump 149. Figures 29C and 29D show examples of adhesive portions 255 that surround multiple bumps 149. Figures 29E and 29F show examples of adhesive portions 255 configured in a linear shape. Figure 29G shows an example of a linear adhesive portion 255 being positioned near bumps 149 arranged in a row.

[0122] The configuration of the display device 10 other than that described above is the same as that of the display device 10 in the first embodiment of this disclosure, so a description will be omitted.

[0123] Thus, in the tenth embodiment of the present disclosure, the display device 10 has an adhesive portion 255 arranged on the substrate 110 near the bump 149. This improves the connection strength between the bump 149 and the pad 240.

[0124] (11. Eleventh Embodiment) The display device 10 of the tenth embodiment described above had an adhesive portion 255 located near the bump 149. In contrast, the display device 10 of the eleventh embodiment of the present disclosure differs from the tenth embodiment described above in that it further includes an adhesive portion 170.

[0125] <Configuration of the display device> Figure 30 is a cross-sectional view showing an example of the configuration of a display device according to the eleventh embodiment of the present disclosure. This figure is a schematic cross-sectional view showing an example of the configuration of the display device 10, similar to Figure 27. The display device 10 in this figure differs from the display device 10 in Figure 27 in that an adhesive portion 170 is further arranged therein.

[0126] As described above, the adhesive portion 170 is placed after the display element 100 and the flexible substrate 200 are connected. In the display device 10 of Figure 30, the connection between the bump 149 and the pad 240 is reinforced by placing the adhesive portion 255. Therefore, the occurrence of defects such as peeling of the bump 149 and the pad 240 can be reduced in the process up to the placement of the adhesive portion 170.

[0127] Figures 31A and 31G show another example configuration of the display device according to the eleventh embodiment of the present disclosure. Variations of the adhesive portion 255 will be explained using Figures 31A and 31G.

[0128] Figures 31A and 31B show examples of linearly configured adhesive portions 255. The white arrows indicate the direction of introduction of the liquid curable resin constituting the adhesive portion 170. As shown in Figures 31A and 31B, it is preferable to arrange the adhesive portion 255 in a shape that secures a flow path for the liquid curable resin constituting the adhesive portion 170. Figure 31C shows an example of an adhesive portion 255 configured in a shape that surrounds a plurality of bumps 149. Figure 31D shows an example in which linear adhesive portions 255 are arranged near bumps 149 that are lined up in a row, similar to Figure 29G. The adhesive portion 255 in Figure 31D is configured in a shape that secures a flow path for the liquid curable resin constituting the adhesive portion 170.

[0129] The configuration of the display device 10 other than that described above is the same as that of the display device 10 in the tenth embodiment of this disclosure, so a description will be omitted.

[0130] Thus, the display device 10 of the eleventh embodiment of this disclosure can further improve the connection strength between the display element 100 and the flexible substrate 200 by including the adhesive portion 170.

[0131] (12. Configuration of the display element) The configuration of the display area 160 of the display element 100 will be explained. The optical element of the display area 160 is made of, for example, organic EL.

[0132] Figure 32 is a cross-sectional view showing an example of the configuration of a display area according to the embodiment of this disclosure. The figure shows a pixel 120 arranged in the display area 160. An optical element is arranged in the pixel 120. This optical element is composed of a lower electrode 116, an organic light-emitting layer 117, and an upper electrode 118. An insulating film 161 is arranged between the lower electrode 116 and the substrate 110. A drive transistor 121 is arranged on the substrate 110. This drive transistor 121 is composed of a semiconductor region 111 formed on the substrate 110 and a gate electrode 114 arranged on the upper surface of the substrate 110 via the insulating film 113. The lower electrode 116 and the semiconductor region 111 are connected by a contact plug 115. Separation regions 112 are arranged between adjacent drive transistors 121. A sealing portion 162 is arranged adjacent to the upper electrode 118. A color filter 122 and an on-chip lens 123 are arranged on the upper layer of the sealing portion 162. A sealing portion 163 is further arranged to cover the color filter 122 and the on-chip lens 123.

[0133] Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur.

[0134] Furthermore, this technology can also take the following configurations: (1) A display element having a terminal connected to an element of the display area, which is embedded in an insulating layer formed at the edge of a substrate on which the display area is arranged, and a void region which is a region that becomes an air gap when the pad is joined to the terminal in a flexible substrate having a pad that is joined to the terminal. (2) The display element according to (1), wherein the terminal and the pad are made of metal and their surfaces are directly joined to each other. (3) The display element according to (1), wherein the void region is formed in a part of the insulating layer adjacent to the terminal. (4) The display element according to (1), wherein the void region is configured in a shape that surrounds the terminal. (5) The display element according to any one of (1) to (4), wherein the void region is formed by etching the insulating layer. (6) The display element according to (1), wherein the void region is formed by laminating a conductive layer that protrudes from the surface of the insulating layer onto the terminal. (7) A display device comprising: a display element having a terminal connected to an element of the display area, which is embedded in an insulating layer formed at the edge of a substrate on which the display area is arranged; a flexible substrate attached to the display element, which has a pad that is joined to the terminal; and a gap region which is a region that becomes an air gap between the pad and the insulating layer when the pad is joined to the terminal. (8) The display device according to (7), wherein the terminal and the pad are made of metal and their surfaces are directly joined to each other. (9) The display device according to (7) or (8), wherein the gap region is configured in a shape that surrounds the terminal. (10) The display device according to any one of (7) to (9), wherein the gap region is formed by etching the insulating layer. (11) The display device according to (7) or (8), wherein the gap region is formed by laminating a conductive layer that protrudes from the surface of the insulating layer onto the terminal. (12) The display device according to (7) or (8), wherein the gap region is formed by a protrusion formed on the pad. (13) The display device according to (12), wherein the protruding portion is composed of a conductive layer laminated on the surface of the pad.(14) The display device according to (12), wherein the protrusion is formed by a step in the flexible substrate. (15) A display device comprising a display element having a terminal connected to an element of the display area, which is embedded in an insulating layer formed at the edge of a substrate on which a display area is arranged, and a flexible substrate attached to the display element, which has a pad that is joined to the terminal, wherein the flexible substrate is made of a flexible film substrate on which a conductor pattern including the pad is formed, and an opening is formed in the flexible film substrate at a position overlapping with the pad. (16) The display device according to (15), wherein the terminal and the pad are made of metal and their surfaces are directly joined to each other. (17) The display device according to (15), wherein the terminal is joined to the pad via a bump formed on the terminal, and the pad is made of metal and is directly joined to the bump. (18) The display device according to any one of (15) to (17), further comprising an adhesive portion disposed between the substrate and the flexible substrate near the terminal after the terminal and the pad have been joined, wherein the adhesive portion is applied and disposed near the terminal through the opening. (19) The display device comprising a display element having a terminal connected to an element of the display area, which is disposed embedded in an insulating layer formed at the end of a substrate on which a display area is arranged; a bump formed on the terminal; a flexible substrate attached to the display element having a pad joined to the bump; and an adhesive portion disposed near the bump for attaching the flexible substrate to the substrate. (20) The display device according to (19), further comprising a gap-forming portion disposed on the flexible substrate for forming a gap between the pad and the adhesive portion when the adhesive portion contacts the flexible substrate. (21) The display device according to (19) or (20), wherein the adhesive portion has an opening through which the bump is inserted.(22) A display device comprising: a display element having terminals connected to elements of the display area, which are embedded in an insulating layer formed at the edge of a substrate on which a display area is arranged; a flexible substrate attached to the display element, which comprises a bump formed on the terminal and a pad joined to the bump; and a second adhesive portion arranged on the surface of the substrate near the bump and configured in an island shape to bond the substrate and the flexible substrate when the terminal and the pad are joined. (23) The display device according to (22), further comprising an adhesive portion arranged between the substrate and the flexible substrate after the terminal and the pad have been joined.

[0135] 10 Display device 100 Display element 110 Substrate 131, 132 Insulating layer 140, 142 Terminal 149 Bump 150, 151 Gap region 160 Display region 161 Insulating film 170, 255 Adhesive part 200 Flexible substrate 210 Substrate 211 Opening 240, 241, 243 Pad 242 Protrusion 244 Step 250 Adhesive part 251 Opening 257 Gap 258, 259 Gap forming part

Claims

1. A display element having a terminal connected to an element of the display area, which is embedded in an insulating layer formed at the edge of a substrate on which the display area is arranged, and a gap region which is a region that becomes an air gap between the pad and the insulating layer when the pad is joined to the terminal in a flexible substrate having a pad that is joined to the terminal.

2. The display element according to claim 1, wherein the terminal and the pad are made of metal and their surfaces are directly joined to each other.

3. The display element according to claim 1, wherein the void region is formed in a portion of the insulating layer adjacent to the terminal.

4. The display element according to claim 1, wherein the air gap region is configured to surround the terminal.

5. The display element according to claim 1, wherein the void region is formed by etching the insulating layer.

6. The display element according to claim 1, wherein the void region is formed by laminating a conductive layer having a shape that protrudes from the surface of the insulating layer onto the terminal.

7. A display device comprising: a display element having a terminal connected to an element of the display area, which is embedded in an insulating layer formed at the edge of a substrate on which the display area is arranged; a flexible substrate attached to the display element, which has a pad that is joined to the terminal; and a gap region which is a region that becomes an air gap between the pad and the insulating layer when the pad is joined to the terminal.

8. The display device according to claim 7, wherein the terminal and the pad are made of metal and their surfaces are directly joined to each other.

9. The display device according to claim 7, wherein the gap region is configured to surround the terminal.

10. The display device according to claim 7, wherein the void region is formed by etching the insulating layer.

11. The display device according to claim 7, wherein the void region is formed by laminating a conductive layer having a shape that protrudes from the surface of the insulating layer onto the terminal.

12. The display device according to claim 7, wherein the void region is formed by a protrusion formed on the pad.

13. The display device according to claim 12, wherein the protruding portion is composed of a conductive layer laminated on the surface of the pad.

14. The display device according to claim 12, wherein the protrusion is formed by a step in the flexible substrate.

Images