Electronic device

Abstract

To provide a stretchable electronic device with high reliability.SOLUTION: A configuration of the present invention includes a stretchable electronic device in which an active region 5 and a terminal region 6 are formed continuously. In the active region 5, a scan line with a meander structure and a signal line with the meander structure are formed. In the terminal region 6, a terminal wire 200 and a terminal 210 are formed on a base material extending in a second direction and arrayed in a first direction. In a part where the terminal 210 is formed, the base material configures a reinforcement material 300 that continues in the first direction.SELECTED DRAWING: Figure 15

Description

[Technical field]

[0001] The present invention relates to flexible and stretchable electronic devices. [Background technology]

[0002] There is an increasing demand for electronic devices that are flexible or stretchable. Applications of such stretchable electronic devices include, for example, attaching them to the housing of an electronic device having a curved surface, attaching them to a display medium having a curved surface, attaching them to the human body as a sensor, etc. Examples of elements include sensors such as touch sensors, temperature sensors, pressure sensors, and acceleration sensors, as well as light-emitting elements and light valves that constitute various display devices.

[0003] In a sensor device, scanning lines and signal lines are used to control each element. In a stretchable electronic device, the device needs to be able to withstand bending and stretching. Patent Document 1 describes a structure in which the scanning lines and video signal lines are made to meander (hereinafter also referred to as a meandering structure) to be able to withstand bending and stretching. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2021-106199 A Summary of the Invention [Problem to be solved by the invention]

[0005] By making the scanning lines and signal lines meandering, it is possible to obtain a certain degree of resistance to stretching and bending of the stretchable electronic device. Even a stretchable display device needs to be supplied with power and signals from the outside. Such power and signal supply is performed via a flexible wiring substrate.

[0006] However, although a flexible wiring board can be bent flexibly, it cannot be expected that it will expand or contract. Therefore, when a stretchable electronic device is stretched, stress is generated between the flexible wiring board and the display device. In addition, flexible wiring boards are often used in a bent state, and when they are bent, stress is likely to be generated between the flexible wiring board and the stretchable electronic device.

[0007] The flexible wiring board and the stretchable display device are connected via a plurality of terminals. Therefore, this stress occurs in the terminal portion. If the stress becomes large, the terminal portion may peel off. Even if peeling does not occur, the connection resistance at the terminal increases. This change in connection resistance is observed as noise.

[0008] The object of the present invention is to avoid stress at the connection between a flexible wiring board and a stretchable electronic device, to prevent connection failure or noise at the connection, and to realize a highly reliable stretchable electronic device. [Means for solving the problem]

[0009] The present invention achieves the above object, and representative means thereof are as follows.

[0010] (1) A stretchable electronic device in which an active area and a terminal area are formed continuously, wherein meander-structured scanning lines and meander-structured signal lines are formed in the active area, and terminal wiring and terminals are formed on a substrate in the terminal area extending in a second direction and arranged in a first direction, and the substrate is continuous in the first direction in the portion where the terminals are formed.

[0011] (2) A stretchable electronic device in which an active area and a terminal area are formed continuously, the active area being formed with meander-structured scanning lines and meander-structured signal lines, the terminal area being formed with terminal wiring and terminals on a base material extending in a second direction and arranged in a first direction, the base material being formed on a first substrate, and a first layer being formed on a surface of the substrate opposite to the surface on which the base material is formed, in a portion corresponding to the terminals, using a material having a larger Young's modulus than that of the base material. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a plan view of a stretchable electronic device as a comparative example. [Diagram 2] 2 is a cross-sectional view taken along line AA in FIG. 1. [Diagram 3] FIG. 2 is an enlarged plan view of an active area. [Figure 4] BB cross-sectional view of FIG. 3. [Diagram 5] 3C is a cross-sectional view taken along line CC in FIG. [Figure 6] FIG. 2 is a plan view showing the element and its periphery. [Figure 7] FIG. 7 is a cross-sectional view taken along the line DD in FIG. 6. [Figure 8] FIG. 1 is a plan view of a stretchable electronic device as a comparative example. [Figure 9] 9 is a cross-sectional view of FIG. 8 taken along line E-E. [Figure 10] FIG. 9 is a cross-sectional view of FIG. 8 shown in FIG. [Figure 11] FIG. 9 is a cross-sectional view of FIG. [Figure 12] 9 is a plan view showing a state in which a flexible wiring board is connected to the stretchable electronic device of FIG. 8. [Figure 13] FIG. 13 is a cross-sectional view of FIG. 12 . [Figure 14] FIG. 13 is a cross-sectional view of FIG. 12 in accordance with II. [Figure 15] FIG. 1 is a plan view of a stretchable electronic device according to a first embodiment. [Figure 16]FIG. 16 is a cross-sectional view of JJ in FIG. [Figure 17] FIG. 16 is a cross-sectional view of FIG. [Figure 18] 16 is a plan view showing a state in which a flexible wiring board is connected to the stretchable electronic device of FIG. 15. [Figure 19] 19 is a cross-sectional view taken along the line L-L in FIG. 18. [Figure 20] FIG. 4 is a plan view showing a second embodiment of the first embodiment. [Figure 21] 21 is a cross-sectional view of FIG. 20 taken along line MM. [Figure 22] FIG. 11 is a plan view of a stretchable electronic device according to a second comparative example. [Figure 23] FIG. 11 is a plan view showing a third embodiment of the first embodiment. [Figure 24] FIG. 11 is a plan view of a stretchable electronic device according to a third comparative example. [Diagram 25] 25 is a cross-sectional view of FIG. 24 shown at N-N. [Figure 26] FIG. 11 is a plan view of a stretchable electronic device according to a second embodiment. [Figure 27] 27 is a cross-sectional view of FIG. 26 in FIG. [Figure 28] FIG. 11 is a plan view of a stretchable electronic device according to a second embodiment of the present invention. [Figure 29] 29 is a cross-sectional view taken along line PP of FIG. 28. [Diagram 30] FIG. 13 is a plan view of a stretchable electronic device according to a fourth comparative example. [Diagram 31] FIG. 11 is a plan view of a stretchable electronic device according to a third embodiment of the present invention; [Diagram 32] FIG. 11 is a plan view of a stretchable electronic device according to a third embodiment. [Diagram 33] 33 is a cross-sectional view of FIG. 32 taken along line R-R. [Diagram 34] 33 is a cross-sectional view of FIG. 32 taken along line S-S. [Diagram 35] 33 is a cross-sectional view of FIG. 32 . [Diagram 36] FIG. 13 is a plan view of a stretchable electronic device according to a third embodiment of the present invention. [Figure 37] FIG. 11 is a plan view of a stretchable electronic device according to a fourth embodiment of the present invention; [Figure 38] FIG. 11 is a plan view of a stretchable electronic device according to a fifth embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention will be described in detail below with reference to the following examples. Hereinafter, the electronic device that can be expanded or contracted is also called a stretchable electronic device. EXAMPLES

[0014] The present invention relates particularly to the configuration of the terminal region of the stretchable electronic device. Since the terminal region 6 is formed simultaneously with the active region 5, the configuration of the active region 5 will be described first. FIG. 1 is a plan view of the stretchable electronic device 1 for explaining the configuration of the active region 5. The active region 5 of the comparative example and the embodiment described later have almost the same configuration. The stretchable electronic device 1 of FIG. 1 is generally flat, but can be curved in the z direction or stretched on the xy plane. The breaking elongation rate, that is, the elongation rate until the stretchable electronic device 1 breaks, varies depending on the material constituting the stretchable electronic device 1. When the stretchable electronic device 1 is mainly made of ductile organic materials, the elongation rate can be about 30%, and in some cases, about 60%. On the other hand, when a relatively large amount of inorganic materials is used, the elongation rate is about 10% to 15%.

[0015] In FIG. 1, the stretchable electronic device 1 has an active area 5 occupying a large area. Electronic elements 100 are arranged in a matrix in the active area 5. The electronic elements 100 may be, for example, sensors, semiconductor elements, actuators, etc. The sensors may be, for example, optical sensors that detect visible light or infrared light, temperature sensors, pressure sensors, touch sensors, etc. The semiconductor elements may be, for example, light-emitting elements, light-receiving elements, diodes, transistors, etc. The actuators may be, for example, piezoelectric elements, etc.

[0016] Each electronic element 100 is connected to a scanning line 110 and a signal line 120. The scanning line 110 extends in the horizontal direction (x direction) and is arranged in the vertical direction (y direction), while the signal line 120 extends in the vertical direction and is arranged in the horizontal direction. In FIG. 1, both the scanning line 110 and the signal line 120 extend in a straight line, but this is for the purpose of not complicating the drawing. In reality, as shown in FIG. 3, the scanning line 110 extends in the horizontal direction and the signal line 120 extends in the vertical direction in a meandering manner.

[0017] In FIG. 1, driving circuits 115, 125 and a terminal area 6 are arranged outside the active area 5. Scanning line driving circuits 115 are arranged on both sides of the active area 5 in the x direction, a power supply circuit 130 for supplying power to the electronic element 100 exists on the upper side of the active area 5 in the y direction, and a signal line driving circuit 125 is arranged on the lower side of the active area 5 in the y direction. The terminal area 6 is arranged further below the signal line driving circuit 125. A flexible wiring board 150 is connected to the terminal area 6 to supply power and signals to the stretchable electronic device 1 and to send signals to the outside. Although not shown, the flexible wiring board 150 is further connected to another wiring board.

[0018] Fig. 2 is a cross-sectional view taken along the line AA in Fig. 1. Fig. 2 is a schematic cross-sectional view. In Fig. 2, the electronic elements 100, scanning lines 110, signal lines 120, etc. described in Fig. 1 are present in an element layer 2. In other words, the function of the stretchable electronic device 1 is present in the element layer 2. This element layer 2 is covered from above by an upper protective layer 3 and from below by a lower protective layer 4. Both the upper protective layer 3 and the lower protective layer 4 are formed from materials that are easily elastically deformed, i.e., materials with a small Young's modulus.

[0019] 2, the active region 5 and the drive circuits 115, 125, etc. are covered by an upper protective layer 3 and a lower protective layer 4. An end portion of the element layer 2 has a portion that is not covered by the upper protective layer 3, and this portion serves as a terminal region 6. The terminal region 6 is protected only by the lower protective layer 4. A flexible wiring board 150 is connected to the terminal region 6.

[0020] Fig. 3 is an enlarged plan view of the active region 5. Fig. 3 shows the main components of the element layer 2 shown in Fig. 2. That is, the element layer 2 shown in Fig. 2 does not exist as a single planar substrate, but is composed of a base material 10 having a meandering structure 102 in which scanning lines 110 and signal lines 120 are formed, and an element region 101 formed at the intersection of the scanning lines 110 and the signal lines 120, as shown in Fig. 3. In other words, the base material 10 has a mesh-like structure.

[0021] In Fig. 3, the meandering structure 102 and the element region 101 present at the intersection are made of a resin such as polyimide. This resin is used as the base material 10, and scanning lines 110, signal lines 120, elements 100, etc. are formed thereon. In Fig. 3, the element 100 is present in the element region 101. The reason for this configuration is to reduce stress on each component even when the stretchable electronic device 1 is stretched.

[0022] 3, the diameter of the element 100 in the x direction and the diameter in the y direction are each, for example, 100 μm. The pitch of the elements 100 in the x direction and the pitch in the y direction are, for example, 250 μm. The width of the substrate 10 including the scanning lines 110, the video signal lines 120, etc. in the meandering structure 102 is, for example, 30 μm.

[0023] Fig. 4 is a BB cross-sectional view of Fig. 3, and is a cross-sectional view of the meander structure 102 including the scanning line 110. In Fig. 4, a first organic insulating film 20 is formed on the substrate 10. The scanning line 110 is formed on the first organic insulating film 20. A second organic insulating film 30 is formed covering the scanning line 110. The plan view of the meander structure 102 including the scanning line 110 in Fig. 3 represents the planar shape of the substrate 10.

[0024] The substrate 10, the first organic insulating film 20, and the second organic insulating film 30 are formed of, for example, polyimide. Polyimide has excellent performance in terms of mechanical strength, heat resistance, and the like, and is therefore suitable as the substrate 10 for the scan lines 110 and the signal lines 120. That is, when the stretchable electronic device 1 is stretched, the stress generated in the meandering structure 102 is borne by the polyimide forming the substrate 10 and the first organic insulating film 20, etc., and therefore the stress applied to the scan lines 110, etc., formed of metal, is reduced.

[0025] The scanning line 110 has, for example, a TAT (Ti-Al-Ti, titanium-aluminum-titanium) structure. In the three-layer structure, Al is mainly responsible for electrical conductivity, and Ti is used to protect Al or to improve the connection with other wiring. In addition, the material of the scanning line 110 can be MoW (molybdenum tungsten alloy), etc., and can have various configurations depending on the application of the stretchable electronic device 1.

[0026] As shown in Fig. 3, the meandering structure 102 having the scanning lines 110 (hereinafter simply referred to as the scanning lines 110) has an unstable shape, so it is fixed from above and below with protective layers (3 and 4 shown in Fig. 2). First, the meandering structure 102 on which the scanning lines 110 are formed is covered with an upper buffer layer 40 made of an organic material. This is then covered with a protective layer 50 made of an organic material. A lower buffer layer 60 made of an organic material is disposed on the lower surface of the substrate 10, and a lower protective layer 70 made of an organic material is formed underneath.

[0027] In this way, the shape is stabilized by the buffer layers 40, 60 and protective layers 50, 70 arranged above and below. Since the electronic device of the present invention is a stretchable electronic device, it is necessary that it is expandable and contractible in response to external tensile stress. Therefore, it is desirable that the buffer layers 40, 60 and protective layers 50, 70 sandwiching the meander structure 102 are made of a material that is easier to stretch than the polyimide that forms the substrate 10 and the first organic insulating film 20, i.e., a material with a small Young's modulus. Examples of such materials include resins such as acrylic, urethane, epoxy, and silicone.

[0028] FIG. 5 is a cross-sectional view taken along the CC line in FIG. 3, and is a cross-sectional view of the meander structure 102 having the signal line 120. In the meander structure 102 in FIG. 5, a first organic insulating film 20 and a second organic insulating film 30 are continuously formed on a substrate 10. The signal line 120 is formed on the second organic insulating film 30. In the first embodiment, the signal line 120 has the same material as the scanning line, that is, a TAT (Ti-Al-Ti) structure, but may be changed to another material depending on the application of the stretchable electronic device. The other structure is the same as the cross-sectional shape of the scanning line 110 portion described in FIG. 4.

[0029] Fig. 6 is an enlarged plan view of the element region 101. The element region 101 is made of a substrate 10 formed in an island shape. The element region 101 in Fig. 6 is roughly octagonal in shape, but may have other shapes. In Fig. 6, both the scanning lines 110 and the signal lines 120 are straight lines, but outside Fig. 6, they have a meandering structure as shown in Fig. 3.

[0030] In Fig. 6, an element 100 is arranged in an element region 101. In the element region 101, a signal line 120 and a scanning line 110 cross each other via an insulating film. However, Fig. 6 is a schematic diagram, and in an actual device, both the scanning line 110 and the video signal line 120 are connected to transistors that drive the element 100.

[0031] Fig. 7 is a DD cross-sectional view of Fig. 6. In Fig. 7, an inorganic insulating film 80 is formed on a substrate 10. The inorganic insulating film 80 blocks impurities and the like that may invade from below toward the elements 100 and the like formed above it. In Fig. 7, the inorganic insulating film 80 is formed on the substrate 10, but this is an example, and the inorganic insulating film 80 may be formed in a layer closer to the elements 100 as necessary.

[0032] The inorganic insulating film 80 is formed of a silicon nitride film (SiN film), a silicon oxide film (SiO film), or a laminated film of these. In some cases, an aluminum oxide film (AlO) may be used. Although the inorganic insulating film 80 has high rigidity, since it is formed only in the element region 101, it has little effect on the stretchability of the stretchable electronic device 1.

[0033] A first organic insulating film 20 is formed of, for example, polyimide, covering the inorganic insulating film 80. Scanning lines 110 extend in the lateral direction (x direction) on the first organic insulating film 20. A second organic insulating film 30 is formed of, for example, polyimide, covering the scanning lines 110 and the first organic insulating film 20. A signal line 120 extends in the y direction on the second organic insulating film 30.

[0034] 7 is a schematic diagram, and does not show the connection structure between the element 100 and the scanning line 110 or the signal line 120. As an example, a thin film transistor (TFT) is disposed between the element 100 and the scanning line 110 or the signal line 120, and the thin film transistor is controlled by a scanning line control circuit 115 or a signal line control circuit 125 to control a signal from the element 100 or a signal to the element 100.

[0035] 7, the wiring structure between the element 100 and the signal line 120 in Fig. 7 varies depending on what is arranged as the element 100. In the element region 101, there is a possibility that a plurality of organic or inorganic insulating films may be formed.

[0036] The planar structure shown in FIG. 6 corresponds to the cross-sectional structure from the substrate 10 to the element 100 in FIG. 7. If left as is, the planar shape will be as shown in FIG. 3, which is unstable. Therefore, as explained in FIG. 4, the upper buffer layer 40, the upper protective layer 50, the lower buffer layer 60, and the lower protective layer 70 are formed, and the whole is put together in a flat plate shape to stabilize the shape. Also, as explained in FIG. 4, the upper buffer layer 40, the upper protective layer 50, the lower buffer layer 60, and the lower protective layer 70 use materials with smaller Young's modulus than the substrate 10, the first organic insulating film 20, the second organic insulating film 30, etc., and therefore, the stretchability of the stretchable electronic device 1 is not impaired.

[0037] Fig. 8 is a detailed plan view of the terminal area 6 of the stretchable electronic device 1 according to a comparative example. In Fig. 8, the configuration of the active area 5 is the same as that described in Figs. 1 to 7. In Fig. 8, the terminal wiring 200 extends in the vertical direction (y direction) like the signal lines 120 of the active area 5. At the lower end of the terminal area 6, a plurality of terminals 210 are arranged in the horizontal direction (x direction).

[0038] Fig. 9 is an E-E cross-sectional view of Fig. 8. In Fig. 9, the upper buffer layer 40 and the upper protective film 50 described in the active region 5 are collectively described as the upper protective layer 3. The lower buffer layer 60 and the lower protective film 70 are collectively described as the lower protective layer 4. Furthermore, the substrate 10, the first organic insulating film 20, and the second organic insulating film 30 are collectively described as the substrate 15. The same applies to the following drawings. As shown in Fig. 9, in the portion where the terminal wiring 200 and the terminal 210 are present, the substrate 15 exists up to the end.

[0039] Fig. 10 is a cross-sectional view taken along line FF in Fig. 8. As shown in Fig. 10, even in the terminal region 6, the base material 15 does not exist in the portions where the terminal wiring 200 and the terminals 210 do not exist. This is to maintain the stretchable structure even in the terminal region 6. Fig. 11 is a cross-sectional view taken along line GG in Fig. 8. In Fig. 11, the base material 15 exists only in the portions where the terminals 210 exist.

[0040] Fig. 12 is a plan view showing a state in which flexible wiring board 150 is connected to terminal area 6 shown in Fig. 8. In Fig. 12, terminals 210 in terminal area 6 and wiring 152 of the flexible wiring board are connected.

[0041] Fig. 13 is an HH cross-sectional view of Fig. 12. In Fig. 13, flexible wiring board 150 is roughly composed of a base material 151, wiring 152, and an overcoat film 153. In Fig. 13, terminals 200 in terminal region 6 and wiring 152 of flexible wiring board 150 are connected by ACF (Anisotropic Conductive Film) 160.

[0042] Fig. 14 is a cross-sectional view taken along line II in Fig. 12. In this portion, terminal wiring 200 and terminals 210 are not present in terminal region 6, and therefore wiring 152 is not present in corresponding flexible wiring board 150. However, ACF 160 is present for bonding flexible wiring board 150 and terminal region 6.

[0043] 12, in the terminal region 6 of the stretchable electronic device 1, similarly to the active region 5, the base material 15 formed of polyimide, which is harder than other organic materials, is shown only in the portion where the meandering wiring 200 and terminals 210 are formed. On the other hand, the flexible wiring board 150 does not have such a structure, and the entire surface of the board 151 is formed of polyimide. As a result, the difference in extensibility between the terminal region 6 and the flexible wiring board 150 becomes very large, especially in the lateral direction (x direction).

[0044] That is, when the stretchable electronic device 1 is stretched, stress is generated between the terminal area 6 and the flexible wiring board 150, especially in the lateral direction (x direction). This stress is generated in a concentrated manner between the wiring 152 of the flexible wiring board 150 and the terminal 210 of the terminal area 6. This makes the connection between the flexible wiring board 150 and the stretchable electronic device 1 unstable, affecting reliability.

[0045] The present invention addresses this problem. Fig. 15 is a plan view showing the configuration of terminal region 6 in Example 1. Fig. 15 differs from Fig. 8, which is a comparative example, in that connecting portion 300 is formed to connect terminals 210.

[0046] 15, the connecting portion 300 is formed from the same material as the base material 15. That is, since it can be formed at the same time as the base material 15, the number of processes does not increase.

[0047] In FIG. 15, the width w1 in the vertical direction (y direction) of the connecting portion 300 is smaller than the width w2 in the vertical direction (y direction) of the terminal 210. However, this is not limiting, and the width w1 in the vertical direction (y direction) of the connecting portion 300 may be adjusted in consideration of the extensibility in the horizontal direction (x direction) of the terminal region 6. For example, the preferred range of the width w1 in the vertical direction (y direction) of the connecting portion 300 is 3 μm or more and equal to or less than the width w2 in the vertical direction (y direction) of the terminal 210. Incidentally, the extensibility can also be expressed by the magnitude of the Young's modulus. That is, the width of the connecting portion 300 can adjust the Young's modulus in the horizontal direction (x direction) of the terminal 210 in the terminal region 6.

[0048] Fig. 16 is a cross-sectional view taken along line JJ in Fig. 15. Fig. 17 is a cross-sectional view taken along line KK in Fig. 15. In Fig. 17, the base material 15 and the connecting portion 300 are continuously formed from the same polyimide, and therefore no boundary actually exists, but in Fig. 17, they are distinguished by a dotted line for ease of understanding. The terminal 210 is formed only on the base material 15.

[0049] Fig. 18 is a plan view showing a state in which flexible wiring board 150 is connected to terminal area 6 in Fig. 15. The basic configuration of Fig. 18 is the same as that described in Fig. 15. That is, the connection portion between terminal 210 and flexible wiring board 150 is the same as the HH cross section of Fig. 12. In Fig. 18, the LL cross section is what differs from the configuration of Fig. 12.

[0050] Fig. 19 is an LL cross-sectional view of Fig. 18. This is a portion where the terminal wiring 200 and the terminal 210 are not present. In Fig. 19, the ACF 160 connects the connecting portion 300 and the base material 151 of the flexible wiring board 150. The presence of the connecting portion 300 reduces the difference in Young's modulus in the horizontal direction (x direction) in Fig. 19 between the flexible wiring board 150 and the terminal 210 portion in the terminal region 6 of the stretchable electronic device 1.

[0051] Fig. 20 is a plan view of the terminal region 6 showing another embodiment of the first embodiment. Fig. 20 differs from Fig. 15 in that a second connecting portion 350 is formed between the terminals 210 in addition to the connecting portion 300. Since the second connecting portion 350 is formed between the terminals 210, it can also be called a bridge layer 350. In Fig. 20, the width w1 of the connecting portions 300 and 350 may be adjusted so that the terminal 210 portion of the terminal region 6 has a predetermined Young's modulus.

[0052] FIG. 21 is an MM cross-sectional view of FIG. 20. In FIG. 21, a second connecting portion 350 is formed on a connecting portion 300. The material of the second connecting portion 350 may be any material as long as it is an insulator. For example, an inorganic film such as silicon oxide (SiO) or silicon nitride (SiN) may be used to effectively adjust the tensile strength in the lateral direction (x direction). In addition, since the second connecting portion 350 uses a material harder than the base material 15, the thickness may be thinner than the base material 15.

[0053] In some cases, the terminal area 6 of the stretchable electronic device 1 may have a small extensibility in the vertical direction (y direction). In this case, the terminal wiring 200 may be linear in the terminal area 6. FIG. 22 is a plan view showing this example. In FIG. 22, the scanning lines 110, the signal lines 120, etc. in the active area 5 have a meandering structure, but the terminal wiring 200 is linear in the vertical direction (y direction). However, in order to maintain a stretchable structure in the horizontal direction (x direction), the base material 15 is formed only under the terminal wiring 200 and the terminals 210. This causes problems similar to those described in FIG. 8 to FIG. 14.

[0054] However, the problem of stress on the terminal 210 caused by the extensibility of the terminal region 6 and the flexible wiring board 150 in the horizontal direction (x direction) is the same whether the terminal wiring 200 has a meandering structure or a straight structure. Fig. 23 is a plan view of the configuration of Fig. 15 applied to the case where the terminal wiring 200 is straight. The coupling portion 300 and other configurations are the same as those in Fig. 15. In this way, with the same configuration as that described in Figs. 15 to 21, the stress on the terminal 210 can be addressed in the configuration of Fig. 23 as well. EXAMPLES

[0055] When the density of the terminal wiring 200 increases, the terminals 210 may be arranged in multiple rows. Fig. 24 is a plan view of a structure in which the terminal wiring 200 has a meandering structure and the terminals 210 are arranged in two rows. Fig. 25 is an N-N cross-sectional view of Fig. 24. Fig. 25 has the same configuration as Fig. 11 of the first embodiment. Meanwhile, the terminals of the flexible wiring board connected to Fig. 24 are also arranged in two rows, as in Fig. 24. Therefore, the configuration of Fig. 24 also has the same problems as those described in the first embodiment.

[0056] Fig. 26 is a plan view of the present invention applied to a configuration in which terminals are arranged in two rows. Since the terminals are formed in two rows, it is necessary to adjust the tensile strength not only in the horizontal direction (x direction) but also in the vertical direction (y direction). Therefore, in Fig. 26, the connecting portion 300 is formed in the horizontal direction (x direction) and the vertical direction (y direction). The tensile strength of the terminal 210 portion can be adjusted by the width w1 of the connecting portion 300.

[0057] Fig. 27 is a cross-sectional view taken along line OO of Fig. 26. In Fig. 27, the dotted line between the base material 15 and the connecting portion 300 is merely for the purpose of explanation, and in reality, they are made of the same polyimide, and there is no boundary between them. In addition, the base material 15 and the connecting portion 300 are made of the same material, and the number of processes does not increase.

[0058] Fig. 28 is a plan view showing another embodiment of the second embodiment. Fig. 28 differs from Fig. 26 in that a second connecting portion 350 is formed on the connecting portion 300. Fig. 29 is a PP cross-sectional view of Fig. 28. As explained in the first embodiment, the material of the second connecting portion 350 may be any material as long as it is an insulator. In order to effectively adjust the Young's modulus in the lateral direction (x direction), an inorganic film such as silicon oxide (SiO) or silicon nitride (SiN) may be used.

[0059] FIG. 30 shows a case where the terminal wiring 200 is straight. However, each wiring in the active region 5 has a meander structure. The QQ cross section of FIG. 30 is the same as that of FIG. 25. Therefore, when the terminal wiring 200 is straight, the same problems as when the terminal wiring 200 has a meander structure occur. FIG. 31 is a plan view of the terminal region 6 when the present invention is applied to the configuration of FIG. 30. The RR cross section of FIG. 31 is the same as that of FIG. 27. Thus, even for the configuration of FIG. 30, by adopting the structure described in FIG. 26 to FIG. 29, it is possible to reduce stress due to the difference in extensibility between the terminal region 6 and the flexible wiring board 150. EXAMPLES

[0060] In the configurations of Examples 1 and 2, on the side of the lower protective layer 4 etc. where the terminals 210 or terminal wiring 200 are formed, the connecting portion 300 is formed from the same material as the substrate 15, or the second connecting portion 350 is formed from a material different from that of the substrate 15. This configuration increases the tensile strength in the arrangement direction of the terminals 210 in the terminal 210 portion of the terminal area 6, thereby obtaining the effect of alleviating stress between the terminal area 6 of the stretchable electronic device and the flexible wiring board.

[0061] In the third embodiment, a material having a larger Young's modulus than the lower protective layer 40 or the base material 15 is formed on the side of the lower protective layer 4 etc. where the terminals 210 or the terminal wiring 200 are formed, thereby increasing the tensile strength in the arrangement direction of the terminals 210 in the terminal region 6. This provides the effect of reducing stress between the terminals 210 in the terminal region 6 and the flexible wiring board 150.

[0062] Fig. 32 is a plan view showing a first form of Example 3. In the terminal region of Fig. 32, the configuration on the side where the terminals 210 and the terminal wiring 200 are formed is the same as that described in Fig. 8. The feature of Fig. 32 is a configuration in which a third coupling portion 400 is formed on the back side of the lower protective layer 4, the third coupling portion 400 having approximately the same width as the terminals 210 and extending in the lateral direction (x direction).

[0063] Fig. 33 is a RR cross-sectional view of Fig. 32, Fig. 34 is a SS cross-sectional view of Fig. 32, and Fig. 35 is a TT cross-sectional view of Fig. 32. The Young's modulus of the material of the third connecting part 400 shown in Figs. 33 to 35 is greater than the Young's modulus of the material constituting the lower protective layer 4 and the material constituting the substrate 15. This is because a predetermined effect can be obtained without increasing the thickness of the third connecting part 400.

[0064] Since the terminal wiring 200 or the terminal 210 is not formed on the side where the third connecting portion 400 is formed, a conductive material can be used as the material of the third connecting portion 400. For example, a transparent conductive film such as ITO (Indium Tin Oxide) or a metal can be used. If the transparent conductive film is used, the appearance of the terminal area hardly changes. When such a material is used, the effect can be obtained if the thickness of the third connecting portion 400 is, for example, about 50 nm.

[0065] There is no problem even if an insulating film is formed as the third connecting portion 400. For example, silicon oxide (SiO) or silicon nitride (SiN) is suitable for the third connecting portion 400 because it has a large Young's modulus and is transparent.

[0066] In Fig. 32, the width of third connecting portion 400 is approximately the same as that of terminal 210, but this width can be changed as necessary. Fig. 36 shows a case in which the width of third connecting portion 400 is smaller than that of terminal 210. The width of third connecting portion 400 can be changed taking into consideration the necessary tensile strength in the lateral direction (x direction), the Young's modulus and thickness of the material forming the third connecting portion, etc.

[0067] 32 to 36 show the case where the terminal wiring 200 in the terminal region 6 has a meander structure, but the third coupling portion 400 can also be applied when the terminal wiring 200 is straight. Fig. 37 is a plan view corresponding to Fig. 32. Fig. 38 is a plan view corresponding to Fig. 36. In either case, the configuration described for the meander structure can be applied to the structure of the third coupling portion 400. [Explanation of symbols]

[0068] 1...stretchable electronic device, 2...element layer, 3...upper protective layer, 4...lower protective layer, 5...active area, 6...terminal area, 10...substrate, 15...substrate, 20...first organic insulating film, 30...second organic insulating film, 40...upper buffer layer, 50...upper protective film, 60...lower buffer layer, 70...lower protective film, 80...inorganic insulating film, 100...element, 101...element area, 102...meander structure, 110...scanning line, 115...scanning line driving circuit, 120...signal line, 125...signal line driving circuit, 130...power supply circuit, 150...flexible wiring board, 151...substrate of flexible wiring board, 152...wiring, 153...overcoat, 160...ACF (anisotropic conductive adhesive), 200...terminal wiring, 210...terminal, 300...Connection part, 350...Second connection part, 400...Third connection part

Claims

1. A substrate having a meander structure and an element region; Wiring located in the meandering structure; an element located in the element region and connected to the wiring, The electronic device has an active area and a terminal area; a plurality of element region portions are provided in the active region, and the meander structure portion is formed so as to connect the element region portions; A plurality of terminals are formed in the terminal region and are arranged in a first direction, The base material has a connecting portion in the terminal region, the plurality of terminals are located at the connecting portion, The electronic device, wherein the connecting portion is formed continuously in the first direction.

2. The electronic device according to claim 1 , wherein a width of the connecting portion in a second direction intersecting the first direction is the same as a width of the terminal in the second direction.

3. The electronic device according to claim 1 , wherein a width of the connecting portion in a second direction intersecting the first direction is smaller than a width of the terminal in the second direction.

4. 2. The electronic device according to claim 1, wherein the base material is made of polyimide.

5. the coupling portion has an insulating layer located between the terminals, The electronic device according to claim 1 , wherein the insulating layer is formed of a material different from that of the base material.

6. The electronic device according to claim 5 , wherein the thickness of the insulating layer is smaller than the thickness of the substrate.

7. The electronic device according to claim 5 , wherein the insulating layer has a Young's modulus greater than that of the base material.

8. The electronic device according to claim 5 , wherein a width of the insulating layer in a second direction intersecting the first direction is the same as a width of the terminals in the second direction.

9. 2. The electronic device according to claim 1, wherein the plurality of terminals include a first row arranged in the first direction and a second row spaced apart from the first row in a second direction intersecting the first direction.

10. An electronic device in which an active area and a terminal area are formed continuously, The electronic device includes a substrate having a meander structure and an element region; Wiring located in the meandering structure; an element located in the element region and connected to the wiring; a plurality of element region portions are provided in the active region, and the meander structure portion is formed so as to connect the element region portions; A plurality of terminals are formed in the terminal region and are arranged in a first direction, the plurality of terminals are formed on one surface of the base material; a connecting portion is formed on the other surface of the base material at a portion corresponding to the plurality of terminals, The electronic device, wherein the connecting portion is formed from a material having a larger Young's modulus than the base material.

11. The electronic device according to claim 10 , wherein the thickness of the connecting portion is smaller than the thickness of the base material.

12. The electronic device according to claim 10 , wherein a width of the connecting portion in a second direction intersecting the first direction is the same as a width of the terminals.

13. The electronic device according to claim 10 , wherein the connecting portion is made of metal.

14. The electronic device of claim 10 , wherein the connecting portion is made of ITO.

15. The electronic device according to claim 10 , wherein the connecting portion is an inorganic insulating film.

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