Stretchable Devices

Abstract

According to one embodiment, provided is an expandable device comprising: an expandable base material; an expandable wire that is provided on the expandable base material; a conductive member that contacts the expandable wire; a solder member that is provided on the conductive member and contacts the conductive member; an electronic component that is electrically connected to the conductive member via the solder member; and a first insulation layer that covers at least a portion of the wire. An outer surface of an end of the expandable wire on the side that contacts the conductive member is in contact with the conductive member and the first insulation layer which is connected to the conductive member.

Description

[Technical field]

[0001] The present invention relates to a stretchable device. [Background technology]

[0002] Conventionally, a stretchable device in which electronic components connected by stretchable wiring are mounted on a stretchable substrate is widely known. For example, Patent Document 1 describes a stretchable device in which a highly wettable conductive member is provided on the wiring, and electronic components are mounted on the conductive member via solder. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6518451 Summary of the Invention [Problem to be solved by the invention]

[0004] In component mounting using solder, there is a risk of a phenomenon called solder erosion, in which brittle compounds are generated by the reaction between the solder and the stretchable wiring through the end of the conductive member. The part where the brittle metal compound is generated is easily broken. In a structure such as that of Patent Document 1, there is a risk of solder erosion of the wiring. Therefore, an object of the present invention is to provide a stretchable device capable of suppressing solder erosion of the wiring. [Means for solving the problem]

[0005] In order to achieve the above object, in one aspect of the present invention, a stretchable device is provided that includes a stretchable substrate, a stretchable wiring provided on the stretchable substrate, a conductive member in contact with the stretchable wiring, a solder member provided on the conductive member and in contact with the conductive member, an electronic component electrically connected to the conductive member via the solder member, and a first insulating layer covering at least a portion of the wiring, wherein the outer surface of the end of the stretchable wiring that contacts the conductive member is in contact with the conductive member and the first insulating layer that is continuous with the conductive member. Effect of the Invention

[0006] According to the stretchable device according to one aspect of the present invention, it is possible to suppress solder erosion of wiring. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a partial top view of a stretchable device according to a first embodiment. [Figure 2A] FIG. 2A is an enlarged perspective view of the elastic wiring. [Figure 2B] FIG. 2B is an enlarged perspective view of the elastic wiring. [Diagram 3] FIG. 3 is a cross-sectional view taken along line III-III of FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. [Diagram 5] FIG. 5 is a partial cross-sectional view of a stretchable device according to a first modified example of the first embodiment. [Figure 6] FIG. 6 is a partial cross-sectional view of a stretchable device according to a second modified example of the first embodiment. [Figure 7] FIG. 7 is a partial cross-sectional view of a stretchable device according to a third modified example of the first embodiment. [Figure 8] FIG. 8 is a partial cross-sectional view of a stretchable device according to a fourth modified example of the first embodiment. [Figure 9] FIG. 9 is a partial cross-sectional view of a stretchable device according to a fifth modified example of the first embodiment. [Figure 10] FIG. 10 is a partial cross-sectional view of the stretchable device according to the second embodiment. [Figure 11] FIG. 11 is a partial cross-sectional view of a stretchable device according to the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. In each embodiment, differences from the previous embodiments will be mainly described. In particular, similar effects due to similar configurations will not be mentioned in each embodiment. Among the components in the following embodiments, components that are not described in the independent claims will be described as optional components. In addition, the size and size ratio of the components shown in the drawings are not necessarily strict. In addition, in each figure, the same reference numerals are given to substantially the same configurations, and duplicated descriptions may be omitted or simplified.

[0009] [First embodiment] The structure of the stretchable device 100 will be described with reference to Figs. 1 to 4. Fig. 1 is a partial top view of the stretchable device according to the first embodiment. Figs. 2A and 2B are enlarged perspective views of a stretchable wiring. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 1. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 1. As shown in Fig. 4, the first insulating layer 6 has a multi-step structure, and in Fig. 1, the parts where steps occur are indicated by straight lines.

[0010] In the stretchable device 100, a stretchable wiring 2 is routed on a stretchable substrate 1, and an electronic component 5 is mounted on the stretchable device 100. FIG. 1 is a partial top view showing an enlarged area where the electronic component 5 is mounted. The shape of the stretchable device 100 is not particularly limited, and may be rectangular or circular when viewed from the thickness direction of the stretchable substrate 1. The arrangement of the stretchable wiring 2 is not particularly limited. In FIG. 1, the longitudinal direction of the stretchable substrate 1 is indicated by a double-headed arrow X. In this embodiment, the direction in which the stretchable device 100 stretches and contracts coincides with the longitudinal direction of the stretchable substrate 1, but it does not have to coincide with this direction.

[0011] The stretchable device 100 comprises a stretchable substrate 1, a stretchable wiring 2 provided on the stretchable substrate 1, a conductive member 3 in contact with the stretchable wiring 2, a solder member 4 provided on the conductive member 3 and in contact with the conductive member 3, an electronic component 5 electrically connected to the conductive member 3 via the solder member 4, and a first insulating layer 6 covering at least a portion of the stretchable wiring 2.

[0012] The arrangement of these components will be described below with reference to Figures 1 and 4. As shown in Figure 1, an elastic wire 2 is provided on an elastic substrate 1. In addition, as shown in Figure 4, a conductive member 3 is in contact with an upper surface 21 and an end surface 24 of the elastic wire 2.

[0013] The stretchable substrate 1 is a sheet-like or film-like stretchable substrate, and is made of, for example, a resin material having stretchability. Examples of the resin material include thermoplastic polyurethane. The thickness of the stretchable substrate 1 is not particularly limited, but from the viewpoint of not inhibiting the stretching of the surface of the living body when attached to the living body, it is preferably 1 mm or less, more preferably 100 μm or less, and even more preferably 50 μm or less. In addition, the thickness of the stretchable substrate 1 is preferably 1 μm or more.

[0014] The stretchable wiring 2 refers to the stretchable wiring 2 that is directly connected to the electronic component 5 among the stretchable wirings 2 that are routed in a predetermined pattern on the main surface of the stretchable substrate 1. That is, the stretchable device 100 may have wiring that is not connected to the electronic component 5. The stretchable wiring 2 contains conductive particles and a resin. For example, a mixture of metal powder such as Ag, Cu, Ni, etc. as the conductive particles and an elastomer resin such as a silicone resin can be mentioned. The average particle size of the conductive particles is not particularly limited, but is preferably 0.01 μm or more and 10 μm or less. In addition, the shape of the conductive particles is preferably spherical.

[0015] The thickness of the elastic wire 2 is not particularly limited, but is preferably 100 μm or less, and more preferably 50 μm or less. The thickness of the elastic wire 2 is preferably 0.01 μm or more. The line width of the elastic wire 2 is not particularly limited, but is preferably 0.1 μm or more, and more preferably 10 mm or less. The number of elastic wires 2 included in the elastic wire 2 is not particularly limited.

[0016] It is preferable to use a conductive member 3 that is less susceptible to solder leaching than the elastic wiring 2. Specifically, it is preferable that the conductive member 3 contains a thermosetting resin. An example of the conductive member 3 containing a thermosetting resin is a compound of a metal filler and a resin containing a thermosetting resin. Examples of the metal filler include a silver filler, a copper filler, and a nickel filler. In this way, when the conductive member 3 contains a thermosetting resin, it is possible to suppress solder leaching due to a reaction between the elastic wiring 2 and the solder member 4. Note that the conductive member 3 may be made of a metal foil or metal plating.

[0017] The solder member 4 is not particularly limited, but preferably contains tin and bismuth as metal components, and is preferably a so-called low-temperature solder. By using the low-temperature solder, even if the heat resistance temperature of the stretchable substrate 1, the stretchable wiring 2, and the electronic component 5 is low, the electronic component 5 can be bonded without damaging them.

[0018] The electronic component 5 is not particularly limited, but examples thereof include an amplifier (an operational amplifier, a transistor, etc.), a diode, an integrated circuit (IC), a capacitor, a resistor, an inductor, and the like.

[0019] The first insulating layer 6 is preferably made of a resin material or a mixture of a resin material and an inorganic material. Examples of the resin material include urethane-based, styrene-based, olefin-based, silicone-based, fluorine-based, nitrile rubber, latex rubber, vinyl chloride, ester-based, amide-based and other elastomer-based resins, epoxy, phenolic, acrylic, polyester, imide-based, rosin, cellulose, polyethylene terephthalate-based, polyethylene naphthalate-based, and polycarbonate-based resins.

[0020] In addition, the outer surface of the end of the elastic wire 2 that comes into contact with the conductive member 3 comes into contact with the conductive member 3 and a first insulating layer 6 that is continuous with the conductive member 3 .

[0021] In this specification, the outer surface refers to the surface of the stretchable wiring 2 excluding the surface on the substrate side. A specific description will be given with reference to FIG. 2A. As shown in FIG. 2A, for example, the surface of the stretchable wiring 2 is composed of an upper surface 21, a lower surface 22, a side surface 23, and an end surface 24. In this specification, the lower surface refers to the surface closest to the stretchable substrate 1, and the upper surface refers to the surface facing the lower surface. In the stretchable device 100 according to the first embodiment, the upper surface 21 is in contact with the conductive member 3, and the lower surface 22 is in contact with the stretchable substrate 1. Note that the stretchable wiring 2 is not limited to a rectangular parallelepiped shape as shown in FIG. 2A, and may have a curved surface or unevenness. Similarly, each surface does not have to be rectangular, and the corners may have R.

[0022] The elastic wiring 2 may have a multi-stage structure as shown in FIG. 2B. When the elastic wiring 2 has a multi-stage structure, there are a plurality of upper surfaces 21 and lower surfaces 22. In this case, as shown in FIG. 2B, in the thickness direction of the elastic substrate 1, the upper surface closest to the electronic component 5 is the uppermost surface 21A, and the upper surface second closest to the electronic component is the second upper surface 21B. The elastic wiring 2 may have a third upper surface, and the number of upper surfaces is not particularly limited.

[0023] As for the lower surface 22, the lower surface closest to the elastic substrate 1 in the thickness direction of the elastic substrate 1 is defined as the lowermost surface 22A, and the second closest lower surface is defined as the second lower surface 22B. The elastic wiring 2 may have a third lower surface, and the number of lower surfaces is not particularly limited.

[0024] In the case of the structure shown in FIG. 2B, the surface closest to the substrate 1 is the bottom surface 22A. That is, the second bottom surface 22B is included in the outer surface, but the bottom surface 22A is not included in the outer surface. Similarly, even if the elastic wiring 2 has a third bottom surface or a fourth bottom surface, they are not included in the outer surface.

[0025] The upper surface 21 and the lower surface 22 do not have to be aligned vertically. These are names for the sake of convenience, and the lower surface may be disposed above the upper surface when the stretchable device 100 is in use. The lower surface 22 and the stretchable substrate 1 do not have to be in contact with each other. As described later, an insulating layer or a thin film may be disposed between the lower surface 22 and the stretchable substrate 1.

[0026] The side surface 23 and the end surface 24 connect the upper surface 21 and the lower surface 22. The elastic wiring 2 has two side surfaces 23 and two end surfaces, but one of the two end surfaces is omitted in FIG. 2A and FIG. 2B. In this specification, the end surface of the elastic wiring 2 that contacts the conductive member 3 is designated as 24. The outer surface of the entire elastic wiring 2 is composed of the upper surface 21, the side surface 23, and both end surfaces, and the outer surface of the end surface of the elastic wiring 2 that contacts the conductive member 3 is composed of the upper surface 21, the side surface 23, and the end surface 24. The end surface of the elastic wiring 2 that contacts the conductive member 3 preferably includes the end surface 24 to the end surface (referred to as end surface A) farther from the end surface 24 among both ends of the conductive member 3 in the extension direction of the wiring, more preferably includes 0.5 mm in addition to the end surface A, and more preferably includes 1 mm in addition to the end surface A. By adopting such a structure, the contact between the elastic wiring 2 and the solder member 4 can be more reliably suppressed.

[0027] The surfaces of each of the components other than the elastic wiring 2 are determined in the same manner. In this specification, the upper surface 21 of the elastic wiring 2 is abbreviated to the upper surface 21. In other words, when each surface is described with a reference symbol, it refers to each surface of the elastic wiring 2. The surfaces of the other components will be described without abbreviating the description and without reference symbols.

[0028] With such a structure, the outer surface of the elastic wire 2 is covered with the conductive member 3 and the first insulating layer 6. That is, the elastic wire 2 and the solder member 4 are less likely to come into contact with each other, so that solder leaching can be suppressed and the reliability of 100 can be improved.

[0029] In addition, the first insulating layer 6 is continuous with the conductive member 3. In other words, as shown in FIG. 4, the first insulating layer 6 and the conductive member 3 are in contact with each other. If the first insulating layer 6 and the conductive member 3 were not in contact with each other, there would be a risk that the solder member 4 would come into contact with the elastic wire 2 from the surface of the conductive member 3 through the end faces of both end faces of the conductive member 3 that are provided on the elastic wire 2. The first insulating layer 6 and the conductive member 3 are continuous with each other, so that the occurrence of solder leaching can be suppressed.

[0030] The conductive member 3 and the first insulating layer 6 being continuous may mean that only the end face of the conductive member 3 and the end face of the first insulating layer 6 are in contact with each other, but it is preferable that the first insulating layer 6 overlaps the end of the conductive member 3 in a plan view. In other words, as shown in FIG. 4, it is preferable that a part of the first insulating layer 6 is provided on the conductive member 3. The wet spread of the solder member 4 stops at the contact point with the first insulating layer 6. That is, by adopting such a structure, the wet spread of the solder member 4 can be suppressed. The first insulating layer 6 and the solder member 4 may be in contact with each other, or may not be in contact with each other as shown in FIG. 4.

[0031] Furthermore, by providing the first insulating layer 6 on the conductive member 3, it is possible to prevent the conductive member 3 from moving toward the electronic component side. In other words, it is possible to improve the connection performance between the conductive member 3 and the stretchable wire 2. When the stretchable device 100 stretches in the extension direction of the stretchable wire 2, it is conceivable that the stretchable wire 2 and the conductive member 3 will peel off due to the difference in the amount of stretch. By providing the first insulating layer 6 on the conductive member 3, it is possible to increase the connection performance between the stretchable wire 2 and the conductive member 3 and suppress peeling.

[0032] 1, the length in the width direction of the elastic wire 2 is preferably smaller than the length in the same direction of the conductive member 3. With such a structure, the conductive member 3 comes into contact with both side surfaces 23 of the elastic wire 2, and contact between the elastic wire 2 and the solder member 4 can be suppressed. Therefore, the reliability of the connection is improved.

[0033] From the viewpoint of connectivity, it is preferable that the contact area between the elastic wire 2 and the conductive member 3 is large. That is, as shown in Figures 3 and 4, it is preferable that the conductive member 3 is in contact with the upper surface 21, both side surfaces 23, and end surface 24 of the wire. Note that the entire conductive member 3 may be provided on the elastic wire 2.

[0034] The solder member 4 is in contact with the upper surface of the conductive member 3. The solder member 4 may be in contact with a surface other than the upper surface of the conductive member 3. Specifically, when viewed from the thickness direction of the stretchable substrate 1, the solder member 4 may be in contact with an end surface or both side surfaces of the conductive member 3 that do not overlap with the stretchable wiring 2. The solder member 4 may also be in contact with the stretchable substrate 1. The shape of the solder member 4 is not particularly limited. For example, the solder member 4 may have a fillet.

[0035] Since the solder member 4 spreads out, it is difficult to accurately control the area. That is, as described above, when the solder member 4 is arranged so as to be in contact with the surface of the conductive member 3 overlapping the stretchable wiring 2 when viewed from the thickness direction of the stretchable substrate 1, the solder member 4 spreads out unintentionally, and the stretchable wiring 2 and the solder member 4 come into contact with each other, which may cause solder leaching.

[0036] The electronic component 5 is electrically connected to the conductive member 3 and the stretchable wire 2 via the solder member 4. As shown in Fig. 1 and Fig. 4, the electronic component 5 is electrically connected to two stretchable wires 2, but may be electrically connected to, for example, four stretchable wires 2.

[0037] The first insulating layer 6 covers at least a part of the stretchable wiring 2, and although its size is not particularly limited, it preferably covers the entire stretchable wiring 2. Note that, as shown in Fig. 1, in addition to the entire stretchable wiring 2, the first insulating layer 6 may be provided so as to be in contact with a part of the stretchable substrate 1, or may cover the entire stretchable substrate 1.

[0038] In addition, the outer surface of the end of the elastic wire 2 that contacts the conductive member 3 is in contact with the conductive member 3 and the first insulating layer 6. As described above, the outer surfaces of the elastic wire 2 are the upper surface 21, both side surfaces 23, and the end surface 24 in contact with the conductive member 3.

[0039] 3, since the width direction length of the elastic wiring 2 is smaller than the width direction length of the conductive member 3, the conductive member 3 is in contact with both side surfaces 23. In the case of such a structure, even if the solder member 4 provided on the upper surface of the conductive member 3 spreads by wetting, it will not come into contact with both side surfaces 23. Note that the conductive member 3 does not need to be in contact with the entirety of both side surfaces 23, and may not be in contact with only a portion of them.

[0040] Similarly, even if the solder member 4 spreads through the end face of the conductive member 3 that is in contact with the stretchable substrate 1, the solder member 4 will not come into contact with the end face 24. It is not necessary for the conductive member 3 to be in contact with the entire end face 24, and it is sufficient for only a portion of the end face to be in contact.

[0041] The upper surface 21 is in contact with the conductive member 3 and the first insulating layer 6 continuous with the conductive member 3. As described above, such a structure can suppress contact between the solder member 4 and the stretchable wiring 2 via the end faces of both end faces of the conductive member 3 that are provided on the stretchable wiring 2. That is, with the above configuration, contact between the solder member 4 and the stretchable wiring 2 can be suppressed via both side faces and both end faces of the conductive member 3, and the reliability of the stretchable device 100 can be improved.

[0042] The first insulating layer 6 is preferably in contact with the end of the conductive member 3. In other words, the first insulating layer 6 is preferably in contact with one end face, both side faces, and the top face of the conductive member 3. By arranging in this manner, contact between the solder member 4 and the stretchable wiring 2 via the end of the conductive member 3 can be suppressed.

[0043] Furthermore, when the stretchable device 100 stretches during use, peeling may occur at the interface between the components. When the first insulating layer 6 is provided on the conductive member 3, the first insulating layer 6, the conductive member 3, and the stretchable wiring 2 overlap when viewed from the thickness direction of the substrate. With this arrangement, the first insulating layer 6 can suppress the upward movement of the conductive member 3. Therefore, peeling in the vertical direction at the interface between the upper surface 21 and the conductive member 3 can be reduced.

[0044] The thickness of each component is not limited to that shown in FIG. 4. In FIG. 4, the thickness of the first insulating layer 6 is greater than the thickness of the stretchable wire 2, but the opposite may also be true. Furthermore, the thickness of the portion of the first insulating layer 6 provided on the stretchable wire 2 and the thickness of the portion provided on the conductive member 3 may be the same or different. The thickness of the portion of the conductive member 3 provided on the stretchable wire 2 and the thickness of the portion provided on the stretchable substrate 1 may be the same or different.

[0045] [First Modification of the First Embodiment] 5 is a partial cross-sectional view of a stretchable device 100A according to a first modified example of embodiment 1. The stretchable device 100A is different from the stretchable device 100 according to embodiment 1 in the arrangement of the conductive members 3 and the solder members 4.

[0046] Also, it is preferable that a part of the first insulating layer 6 is in contact with both the conductive member 3 and the solder member 4. As described above, when the elastic wiring 2 and the solder member 4 come into contact with each other, solder erosion may occur. Similarly, when the conductive member 3 and the solder member 4 come into contact with each other, solder erosion may also occur in the conductive member 3. The larger the contact area between the conductive member 3 and the solder member 4, the higher the possibility that solder erosion will occur in the conductive member 3.

[0047] However, the connection performance of the solder member 4 is greatly affected by the contact area with other members. In other words, if the contact area of ​​the solder member 4 is small, the interface of the solder member 4 may break during expansion and contraction, increasing the risk of defects occurring. In other words, it is preferable to increase the contact area of ​​the solder member 4 without increasing the contact area between the conductive member 3 and the solder member 4.

[0048] Increasing the connection area between the solder member 4 and a member where solder leach is unlikely to occur suppresses solder leach of the conductive member 3, and increasing the contact area of ​​the solder member 4 suppresses breakage of the interface of the solder member 4 during expansion and contraction. With the above-mentioned structure, the contact area between the first insulating layer 6, where solder leach is unlikely to occur, and the solder member 4 is increased.

[0049] Moreover, it is more preferable that the first insulating layer 6, the conductive member 3, and the solder member 4 overlap each other in a planar view. The above-mentioned portions also overlap the elastic wire 2 in a planar view. That is, the possibility that the elastic wire 2 and the conductive member 3 are broken vertically can be further reduced.

[0050] It is more preferable that the solder member 4 contacts the first insulating layer 6 in the extension direction of the wiring. When the conductive member 3 has poorer elasticity than the elastic wiring 2, such as when the conductive member 3 contains a thermosetting resin, increasing the area of ​​the conductive member 3 in a planar view significantly reduces the elasticity of the stretchable device 100A. However, reducing the area of ​​the conductive member 3 also reduces the connection area with the solder member 4, resulting in a decrease in connection performance. By having the solder member 4 contact the first insulating layer 6 in the extension direction of the wiring, it is possible to increase the connection area between the solder member 4 and the conductive member 3 and improve connection performance.

[0051] Similarly, in a plan view, it is preferable that the entire solder member 4 overlaps with the conductive member 3. This increases the connection area between the conductive member 3 and the solder member 4, and improves connection performance.

[0052] 5, it is further preferable that a portion of the first insulating layer 6 is disposed between the solder member 4 and the conductive member 3. As shown in FIG. 5, in addition to the end faces of the insulating layer, a portion of the upper surface also comes into contact with the solder member 4, so that the contact area of ​​the solder member 4 is increased. In other words, peeling of the solder member 4 can be suppressed, and the contact area between the solder member 4 and the conductive member 3 can be increased. Note that a portion of the solder member 4 may be disposed between the conductive member 3 and the first insulating layer 6.

[0053] The thickness of the first insulating layer 6 disposed between the conductive member 3 and the solder member 4 is not particularly limited. It may be the same as the thickness of the first insulating layer 6 provided on the elastic wiring 2, or it may be different.

[0054] [Second Modification of the First Embodiment] 6 is a partial cross-sectional view of a stretchable device 100B according to a second modified example of embodiment 1. The stretchable device 100B is different from the stretchable device 100 according to embodiment 1 in the arrangement of the stretchable wiring 2 and the conductive member 3.

[0055] 6, in the stretchable device 100B, a part of the stretchable wiring 2 is disposed on the conductive member 3, and a first insulating layer 6 is disposed between a part of the stretchable wiring 2 in the longitudinal direction of the stretchable substrate 1 and the solder member 4. With this configuration, one end face and the upper face of the conductive member 3 come into contact with the stretchable wiring 2, making it possible to suppress breakage during stretching.

[0056] In addition, when a part of the elastic wire 2 is on the conductive member 3 in this way, it is preferable to dispose a first insulating layer 6 between the elastic wire 2 and the solder member 4 in order to suppress contact between them. The first insulating layer 6 can suppress solder erosion of the elastic wire 2.

[0057] Moreover, by arranging in this manner, the contact area between the stretchable wiring 2 and the conductive member 3 can be increased while the thickness of the conductive member 3 can be made closer to uniform. As shown in FIG. 6, in a plan view, the electronic component 5 overlaps the stretchable substrate 1, the conductive member 3, and the solder member 4. That is, these three members determine the flatness of the electronic component 5. If the flatness of the electronic component 5 is impaired, the reliability of the component decreases. That is, by adopting such a structure, the contact area between the stretchable wiring 2 and the conductive member 3 can be increased while suppressing a decrease in the reliability of the component.

[0058] The shape of the first insulating layer 6 is not particularly limited, and may be made to match the unevenness of the conductive member 3 by making the thickness constant as shown in Figure 6, or may be printed with a variable thickness to match the height of the upper surface.

[0059] [Third Modification of the First Embodiment] 7 is a partial cross-sectional view of a stretchable device 100C according to a third modified example of embodiment 1. The stretchable device 100C is different from the stretchable device 100 according to embodiment 1 in that the first insulating layer 6 is different.

[0060] 7, in the stretchable device 100C, a part of the stretchable wiring 2 is disposed under the conductive member 3. By disposing in this manner, the upper surface 21 and the end surface 24 come into contact with the stretchable wiring 2. That is, the contact area between the stretchable wiring 2 and the conductive member 3 is increased, and breakage during stretching can be suppressed.

[0061] Moreover, it is preferable that the elastic wiring 2 includes a first portion 7 having a large thickness and a second portion 8 having a smaller thickness than the first portion 7, and that at least a portion of the second portion 8 is disposed below the conductive member 3. As described above, by disposing a portion of the elastic wiring 2 below the conductive member 3, the upper surface 21 and the end surface 24 can be disposed so as to contact the conductive member 3.

[0062] In a plan view, the shortest distance from the stretchable substrate 1 to the portion of the conductive member 3 that overlaps the stretchable wire 2 and the portion that does not overlap the stretchable wire 2 differs by the thickness of the second portion 8. That is, if the thickness of the second portion 8 is large, the unevenness of the conductive member 3 becomes large, impairing flatness.

[0063] That is, by disposing at least a part of the second portion 8 of the elastic wire 2, which has a smaller thickness, under the conductive member 3, it is possible to increase the contact area between the elastic wire 2 and the conductive member 3 and to suppress loss of flatness of the conductive member 3. In addition, it is possible to reduce the height of the region where the electronic component 5 is mounted.

[0064] There is no particular limitation on the length of the second portion 8. As shown in FIG 7, a part of the second portion 8 may be disposed under the conductive member 3, or the entire second portion 8 may be disposed under the conductive member 3.

[0065] [Fourth Modification of the First Embodiment] 8 is a partial cross-sectional view of a stretchable device 100D according to a fourth modified example of embodiment 1. The stretchable device 100D is different from the stretchable device 100 according to embodiment 1 in the arrangement of the stretchable wiring 2 and the first insulating layer 6.

[0066] It is preferable that a part of the elastic wire 2 contacts each of the upper surface and the lower surface of the conductive member 3. Specifically, as shown in Fig. 8, it is preferable that the elastic wire 2 is bifurcated and the conductive member 3 is disposed between them.

[0067] For example, the elastic wire 2 is printed once, then the conductive member 3 is printed so as to overlap a part of it, and the elastic wire 2 is printed again, thereby obtaining the structure shown in Fig. 8. Note that the above printing method is merely one example, and a different manufacturing method may be used.

[0068] By adopting the above-mentioned structure, the elastic wiring 2 contacts one end face, the upper face, and the lower face of the conductive member 3. That is, the contact area increases, and the reliability at the time of connection increases. In addition, as described above, the elastic wiring 2 in contact with the upper face of the conductive member 3 can suppress peeling between the conductive member 3 and the elastic wiring 2 in contact with the lower face of the conductive member 3.

[0069] Similarly, the elastic wiring 2 in contact with the lower surface of the conductive member 3 can suppress peeling between the conductive member 3 and the elastic wiring 2 in contact with the upper surface of the conductive member 3. In other words, by arranging the elastic wiring 2 above and below the conductive member 3, it is possible to suppress deformation of the conductive member 3. Furthermore, by having the elastic wiring 2 in contact with the upper and lower surfaces of the conductive member 3, if either of the contact portions peels off, electrical connection can be ensured at the other contact portion.

[0070] In addition, the thickness of the elastic wiring 2 may be the same as or different from that of the portion in contact with the upper surface and the lower surface of the conductive member 3. In addition, there is no particular limitation on the length, and as shown in Fig. 8, the portion in contact with the lower surface of the conductive member 3 may be longer than the portion in contact with the upper surface of the conductive member 3, or may be the same, or the portion in contact with the upper surface may be longer.

[0071] In addition, a first insulating layer 6 is disposed between a part of the stretchable wiring 2 in the longitudinal direction of the stretchable substrate 1 and the solder member 4. With this configuration, one end face and the upper face of the conductive member 3 come into contact with the stretchable wiring 2, making it possible to suppress breakage during stretching.

[0072] [Fifth Modification of the First Embodiment] 9 is a partial cross-sectional view of a stretchable device 100E according to a fifth modified example of embodiment 1. The stretchable device 100E differs from the stretchable device 100 according to embodiment 1 in that it includes a second insulating layer 9.

[0073] The second insulating layer 9 is preferably made of a resin material or a mixture of a resin material and an inorganic material, and examples of the resin material include urethane, styrene, olefin, silicone, fluorine, nitrile rubber, latex rubber, vinyl chloride, ester, amide, and other elastomer resins, epoxy, phenol, acrylic, polyester, imide, rosin, cellulose, polyethylene terephthalate, polyethylene naphthalate, and polycarbonate resins. The material may be the same as that of the first insulating layer 6, or may be a different material.

[0074] It is preferable that the second insulating layer 9 is further provided, and that the second insulating layer 9 is in contact with an end portion of the conductive member 3 on the opposite side to the side in contact with the first insulating layer 6. As described above, it is preferable to provide the first insulating layer 6 so as to overlap the conductive member 3 in order to suppress peeling between the conductive member 3 and the upper surface 21. The second insulating layer 9 can suppress peeling between the conductive member 3 and the end surface 24.

[0075] Specifically, as shown in Fig. 9, the second insulating layer 9 is disposed at the end of the conductive member 3 that overlaps with the electronic component 5 in a plan view. By disposing in this manner, it is possible to prevent the conductive member 3 from moving in the opposite direction to the elastic wiring 2. In other words, it is possible to prevent the conductive member 3 from peeling off from the end surface 24.

[0076] Also, it is preferable that a part of the second insulating layer 9 is provided on an end of the conductive member 3, and it is further preferable that a part of the second insulating layer 9 is disposed between the solder member 4 and the conductive member 3. As with the first insulating layer 6, peeling can be suppressed by increasing the connection area with the conductive member 3 or the solder member 4. Also, it is preferable that the second insulating layer 9 is in contact with the solder member 4 in the extension direction of the wiring. As with the first insulating layer 6, it is possible to maximize the area between the solder member 4 and the conductive member 3.

[0077] Furthermore, by providing a part of the second insulating layer 9 on the end of the conductive member 3, it is possible to prevent the conductive member 3 from moving toward the electronic component 5. In other words, it is possible to prevent the stretchable substrate 1 and the conductive member 3 from peeling off from each other.

[0078] It is also preferable that the flexible wiring 2 is provided so as to be spaced apart from each other and facing each other, and that the second insulating layer 9 is in contact with an end portion opposite the side in contact with the first insulating layer 6 based on the conductive member 3 in contact with one of the flexible wiring 2, and with an end portion opposite the side in contact with the first insulating layer 6 based on the conductive member 3 in contact with the other flexible wiring 2.

[0079] Specifically, as shown in Fig. 9, a plurality of conductive members 3 are provided in contact with each of a plurality of elastic wires 2, and a second insulating layer 9 is in contact with the plurality of conductive members 3. By providing a first insulating layer integral with the elastic wires 2 that face each other at a distance in this manner, peeling between the two can be further suppressed by the law of action and reaction.

[0080] That is, when a force acts to cause one conductive member 3 and the first insulating layer 6 to peel off in the longitudinal direction of the stretchable substrate 1, the other conductive member 3 can suppress the peeling. When the other conductive member 3 and the first insulating layer 6 peel off in the longitudinal direction of the stretchable substrate 1, the one conductive member 3 and the first insulating layer 6 suppress the peeling. Note that the contact portion that may peel off in the longitudinal direction of the stretchable substrate 1 is not limited to the conductive member 3 and the first insulating layer 6. For example, as shown in FIG. 9, peeling in the longitudinal direction of the stretchable substrate 1 can be suppressed for the connection portion between the end surface 24 and the conductive member 3. Note that the longitudinal direction of the stretchable substrate 1, in which peeling is likely to occur, i.e., the stretching direction, has been described, but the direction in which they are spaced apart and opposed is not particularly limited.

[0081] As described above, the number of the stretchable wirings 2 connected to the electronic component 5 is not particularly limited. When there are a plurality of sets of the stretchable wirings 2 facing each other at a distance, it is preferable to provide a second insulating layer 9 for each set, and it is preferable to provide a second insulating layer 9 that contacts all of the conductive members 3. That is, since unevenness in the region overlapping the electronic component 5 in a plan view is reduced, the electronic component 5 can be stably arranged.

[0082] [Second embodiment] 10 is a partial cross-sectional view of a stretchable device 101 according to the second embodiment. The stretchable device 101 differs from the stretchable device 100 according to the first embodiment in that it includes a protective layer 10.

[0083] The protective layer 10 is a layer for protecting the elastic wire 2 from moisture. When the elastic wire 2 absorbs moisture, ion migration occurs, and there is a risk of short circuiting due to electrical conduction with wiring of a different potential. By providing the protective layer 10, ion migration of the elastic wire 2 can be suppressed.

[0084] The protective layer 10 is preferably made of a resin material or a mixture of a resin material and an inorganic material, and examples of the resin material include urethane, styrene, olefin, silicone, fluorine, nitrile rubber, latex rubber, vinyl chloride, ester, amide, and other elastomer resins, epoxy, phenol, acrylic, polyester, imide, rosin, cellulose, polyethylene terephthalate, polyethylene naphthalate, and polycarbonate resins. The material may be the same as or different from that of the first insulating layer 6 and the second insulating layer 9.

[0085] From the viewpoint of water absorption as the protective layer 10, it is preferable to select a material with high water absorption rate for the protective layer 10. Furthermore, by selecting the same material for the first insulating layer 6, the second insulating layer 9, and the protective layer 10, the materials covering the outer surface of the elastic wiring 2 are the same except for the conductive member 3, which facilitates formation during printing and reduces the risk of defects.

[0086] As shown in Fig. 10, the protective layer 10 may be disposed integrally with the bottom surfaces 22 of the multiple elastic wires 2 so as to be in contact with them, or may be disposed separately for each elastic wire 2. In addition, it is preferable that the protective layer 10 is disposed between the conductive member 3 and the elastic substrate 1. This increases the contact area of ​​the conductive member 3 and can suppress breakage.

[0087] [Third embodiment] 11 is a partial cross-sectional view of a stretchable device 102 according to the third embodiment. The stretchable device 102 differs from the stretchable device 100 according to the first embodiment in that a resin layer 11 is provided.

[0088] 11, the package further includes a resin layer 11 that covers the electronic components 5. The resin layer 11 can protect the electronic components 5 from external forces.

[0089] Examples of materials for the resin layer 11 include elastomer resins such as polyvinyl chloride, polyethylene, polystyrene, polycarbonate, polyvinylidene fluoride, polyimide, liquid crystal polymer, polytetrafluoroethylene, phenolic resin, epoxy resin, urethane resin, acrylic resin, silicone resin, and styrene-butadiene resin.

[0090] When the resin layer 11 is provided, the stretchable device 100 shrinks as the resin contained in the resin layer 11 hardens. That is, there is a risk that the interfaces of the components of the stretchable device 100 may peel off when the components shrink. As described above, by providing the first insulating layer 6 on the conductive member 3, peeling due to shrinkage during the resin effect can be suppressed. The same applies to other peeling suppression effects.

[0091] In plan view, the resin layer 11 preferably overlaps the entire solder member 4, and more preferably overlaps the entire conductive member 3 and the solder member 4. In other words, the surface 12 of the resin layer 11 is preferably in contact with the conductive member 3, and more preferably the surface 12 of the resin layer 11 is in contact with the first insulating layer 6. In Fig. 11, the contact portion between the surface 12 of the resin layer 11 and the first insulating layer 6 is shown as a contact point 13. By arranging them in this way and achieving the above-mentioned structure, breakage can be suppressed.

[0092] The resin layer 11 has a role of protecting the electronic component 5 from external forces, and therefore has inferior elasticity compared to the elastic wiring 2. Therefore, the amount of expansion and contraction changes greatly at the interface between the part that overlaps with the resin layer 11 and the part that does not overlap in a planar view. In the part where the amount of expansion and contraction changes greatly, stress is likely to concentrate, and therefore breakage is likely to occur. More specifically, if the solder member 4 has a structure in which a part of the solder member 4 overlaps with the resin layer 11 and a part of the solder member 4 does not overlap with the resin layer 11 in a planar view, there is a risk that the solder member 4 will break. The same applies to the conductive member 3.

[0093] On the other hand, by arranging the resin layer 11 so as to overlap the entire solder member 4 in a plan view, the solder member 4 is included inside the resin layer. In other words, the amount of expansion and contraction of the entire solder member 4 becomes more uniform, which makes it possible to suppress breakage of the solder member 4. The same applies to the conductive member 3.

[0094] In each of the embodiments and modifications described above, the first insulating layer 6 covers the conductive member 3. The present invention is not limited to the above-described structure, and it is sufficient that the conductive member 3 and the first insulating layer 6 are continuous. Specifically, the end face of the conductive member 3 and the first insulating layer 6 are in contact with each other, but do not have to overlap in a plan view.

[0095] Each embodiment is merely an example, and the present invention is not limited to each embodiment. In addition, partial replacement or combination of configurations shown in different embodiments is possible.

[0096] The aspects of the stretchable device according to one embodiment of the present invention are as follows. <1> A stretchable substrate; An elastic wiring provided on the elastic substrate; A conductive member in contact with the elastic wiring; a solder member provided on the conductive member and in contact with the conductive member; an electronic component electrically connected to the conductive member via the solder member; A first insulating layer covering at least a portion of the elastic wiring, A stretchable device, wherein an outer surface of an end of the stretchable wiring that contacts the conductive member is in contact with the conductive member and the first insulating layer that is continuous with the conductive member. <2> the first insulating layer contacts an end of the conductive member; <1> 2. The stretchable device according to claim 1 . <3> In a plan view, the first insulating layer overlaps an end of the conductive member. <1> or <2> 2. The stretchable device according to claim 1 . <4> a portion of the first insulating layer contacts both the conductive member and the solder member; <3> 2. The stretchable device according to claim 1 . <5> In a plan view, the first insulating layer, the conductive member, and the solder member overlap each other. <1> from <4> 13. The stretchable device according to any one of the preceding claims. <6> a portion of the first insulating layer is disposed between the solder member and the conductive member; <5> 2. The stretchable device according to claim 1 . <7> A portion of the elastic wiring is disposed on the conductive member, and the first insulating layer is disposed between a portion of the elastic wiring and the solder member. <1> from <6> 13. The stretchable device according to any one of the preceding claims. <8> A portion of the elastic wiring is disposed under the conductive member. <1> from <7> 13. The stretchable device according to any one of the preceding claims. <9> The elastic wiring includes a first portion having a large thickness and a second portion having a smaller thickness than the first portion, and at least a portion of the second portion is disposed under the conductive member. <1> from <8> 13. The stretchable device according to any one of the preceding claims. <10> A portion of the elastic wiring contacts the upper and lower surfaces of the conductive member, <1> from <9> 13. The stretchable device according to any one of the preceding claims. <11> Further comprising a second insulating layer; The second insulating layer is in contact with an end portion of the conductive member opposite to the end in contact with the first insulating layer. <1> from <10> 13. The stretchable device according to any one of the preceding claims. <12> a portion of the two insulating layers disposed on the opposite ends of the conductive member; <11> 2. The stretchable device according to claim 1 . <13> The elastic wire is provided so as to face each other at a distance. The second insulating layer is in contact with an end portion opposite to the side in contact with the first insulating layer with respect to the conductive member in contact with one of the elastic wirings, and an end portion opposite to the side in contact with the first insulating layer with respect to the conductive member in contact with the other elastic wiring, <11> or <12> 2. The stretchable device according to claim 1 . <14> Further comprising a protective layer; The protective layer is disposed between the elastic wiring and the elastic substrate. <1> from <13> 13. The stretchable device according to any one of the preceding claims. <15> Further comprising a resin layer covering the electronic component. <1> from <14> 13. The stretchable device according to any one of the preceding claims. <16> The conductive member includes a thermosetting resin. <1> from <15> 13. The stretchable device according to any one of the preceding claims. [Industrial Applicability]

[0097] The stretchable device according to an embodiment of the present invention can be used with electronic components mounted thereon.

[0098] This application claims priority under the Paris Convention based on Japanese Patent Application No. 2021-199233 (filing date: December 8, 2021, title of invention: "Stretchable Device"). All contents disclosed in the application are incorporated herein by reference. [Explanation of symbols]

[0099] 1: Stretchable base material 2:Stretchable wiring 3: Conductive material 4: Solder materials 5: Electronic components 6: First insulating layer 7: Part 1 8:Second part 9: Second insulating layer 10:Protective layer 11: Resin layer 12: Surface of the resin layer 13: Contact point 21: Upper surface 21A: Topmost surface 21B: Second upper surface 22: Lower surface 22A: Lowermost surface 22B: Second lower surface 23: Side surface 24: End face 100, 100A, 100B, 100C, 100D, 100E, 101, 102: Stretchable device

Claims

1. A stretchable substrate; An elastic wiring provided on the elastic substrate; A conductive member in contact with the elastic wiring; a solder member provided on the conductive member and in contact with the conductive member; an electronic component electrically connected to the conductive member via the solder member; A first insulating layer covering at least a portion of the elastic wiring, The outer surface of the end of the elastic wiring that contacts the conductive member is in contact with the conductive member and the first insulating layer that is continuous with the conductive member, In a plan view, the first insulating layer, the conductive member, and the solder member overlap each other, and a portion of the first insulating layer is disposed between the solder member and the conductive member. A stretchable device.

2. A stretchable substrate; An elastic wiring provided on the elastic substrate; A conductive member in contact with the elastic wiring; a solder member provided on the conductive member and in contact with the conductive member; an electronic component electrically connected to the conductive member via the solder member; A first insulating layer covering at least a portion of the elastic wiring, The outer surface of the end of the elastic wiring that contacts the conductive member is in contact with the conductive member and the first insulating layer that is continuous with the conductive member, A stretchable device, wherein a portion of the stretchable wiring is disposed on the conductive member, and the first insulating layer is disposed between a portion of the stretchable wiring and the solder member.

3. A stretchable substrate; An elastic wiring provided on the elastic substrate; A conductive member in contact with the elastic wiring; a solder member provided on the conductive member and in contact with the conductive member; an electronic component electrically connected to the conductive member via the solder member; A first insulating layer covering at least a portion of the elastic wiring, The outer surface of the end of the elastic wiring that contacts the conductive member is in contact with the conductive member and the first insulating layer that is continuous with the conductive member, The stretchable wiring comprises a first portion having a large thickness and a second portion having a smaller thickness than the first portion, and at least a portion of the second portion is disposed under the conductive member. A stretchable device.

4. A stretchable substrate; An elastic wiring provided on the elastic substrate; A conductive member in contact with the elastic wiring; a solder member provided on the conductive member and in contact with the conductive member; an electronic component electrically connected to the conductive member via the solder member; A first insulating layer covering at least a portion of the elastic wiring, The outer surface of the end of the elastic wiring that contacts the conductive member is in contact with the conductive member and the first insulating layer that is continuous with the conductive member, A stretchable device, wherein a portion of the stretchable wiring contacts each of the upper and lower surfaces of the conductive member.

5. The stretchable device according to any one of claims 1 to 4, wherein the first insulating layer overlaps an end of the conductive member in a planar view.

6. Further comprising a second insulating layer; The stretchable device according to any one of claims 1 to 4, wherein the second insulating layer is in contact with an end portion opposite to the end in contact with the first insulating layer with respect to the conductive member.

7. 7. The stretchable device of claim 6, wherein a portion of the second insulating layer is disposed on the opposing end of the conductive member.

8. The elastic wire is provided so as to face each other at a distance. The second insulating layer is in contact with an end portion opposite to the side in contact with the first insulating layer with respect to the conductive member in contact with one of the stretchable wirings, and an end portion opposite to the side in contact with the first insulating layer with respect to the conductive member in contact with the other stretchable wiring. The stretchable device according to claim 6, wherein the end portion contacts the end portion opposite to the side in contact with the first insulating layer with respect to the conductive member in contact with the other stretchable wiring.

9. Further comprising a protective layer; The stretchable device according to any one of claims 1 to 4, wherein the protective layer is disposed between the stretchable wiring and the stretchable substrate.

10. The stretchable device according to any one of claims 1 to 4, further comprising a resin layer covering the electronic component.

11. The stretchable device according to any one of claims 1 to 4, wherein the conductive member comprises a thermosetting resin.

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