JP6416562B2 - Circuit board - Google Patents

Description

  The present invention relates to a stretchable substrate and a circuit board.

  A sheet-like extensible organic base material in which a solid difficult-to-extend polymer portion is partially and integrally formed in an easily extensible polymer base material is known (see, for example, Patent Document 1).

JP 2012-214699 A

  The solid difficult-to-extend polymer part embedded in the easy-extensible polymer base material is relatively hard with respect to the base material. For this reason, when a sheet-like extensible organic base material is expanded and contracted, there is a problem in that there is a possibility that a difficult expansion / contraction part may be peeled off from the base material at an interface parallel to the expansion / contraction direction.

  The problem to be solved by the present invention is to provide a stretchable substrate including a hardly stretchable portion that can be prevented from peeling from a base material, and a circuit board including the stretchable substrate.

[1] A circuit board according to the present invention includes a stretchable substrate including a stretchable base material, a hard stretchable portion embedded in the base material and relatively harder than the base material, and the difficult At least one electronic component provided on the base material so as to overlap the stretchable part or overlap the difficult stretchable part, and provided on the difficult stretchable part, or the difficult stretchable part And at least one wiring provided on the base material so as to overlap, and the hard stretchable part has through holes that penetrate the first and second main surfaces of the hard stretchable part. And the base has a covering portion that covers at least one of the first main surface and the second main surface, and the through-hole protrudes from a part of the covering portion. The base material is filled in at least a part of the through hole so as to be in contact with the inner surface of the through hole. The features.

  [2] In the above invention, the hard stretchable part may be embedded in the base material so that the whole surface of the hard stretchable part is covered with the base material.

  [3] In the above invention, the through hole may have a shape such that a cross section substantially perpendicular to the through direction of the through hole is point-symmetric with respect to the center of the cross section. .

  [4] In the above invention, the difficult stretchable part may have a plurality of the through holes.

  [5] In the above invention, the plurality of through holes may be arranged so as to be point-symmetric with respect to the center of the difficult stretchable part.

[ 6 ] In the above invention, the plurality of electronic components are m × n thin film transistors arranged in a matrix of m rows and n columns along the first and second directions, and the wiring includes the first and second thin film transistors. N first scanning wirings that electrically connect source electrodes or drain electrodes of the m thin film transistors arranged along one direction, and are electrically insulated from the first scanning wirings. And m second scanning wirings that electrically connect the gate electrodes of the n thin film transistors arranged along the second direction to each other.

  The hardly stretchable part in the present invention has a through-hole penetrating the first and second main surfaces of the hardly stretchable part. Moreover, the base material has the coating | coated part which coat | covers at least one of the 1st and 2nd main surface. By projecting a part of the covering portion, at least a part of the through hole is filled so that the base material comes into contact with the inner surface of the through hole. As a result, the shear stress applied to the first and second main surfaces is reduced by the vertical shear stress generated on the inner surface of the through-hole, so that the hardly stretchable portion is separated from the base material along the stretch direction of the stretchable substrate. It can suppress peeling.

FIG. 1 is a plan perspective view of a circuit board according to the first embodiment of the present invention. FIG. 2 is a view showing the stretchable substrate in the first embodiment of the present invention, FIG. 2 (a) is a plan perspective view, and FIG. 2 (b) is a IIb-IIb line in FIG. 2 (a). FIG. FIG. 3 is a view showing a first modification of the stretchable substrate in the first embodiment of the present invention, FIG. 3 (a) is a plan perspective view, and FIG. 3 (b) is FIG. 3 (a). FIG. 3 is a cross-sectional view taken along line IIIb-IIIb. 4 is a cross-sectional view taken along line IV-IV in FIG. 1 of the circuit board according to the first embodiment of the present invention. FIG. 5 is a diagram for explaining the positional relationship between the through holes of the circuit board, the electronic components, and the wirings according to the first embodiment of the present invention, and is a plan view of the hardly stretchable part. FIG. 6A to FIG. 6C are cross-sectional views showing the manufacturing process of the difficult stretchable part in the first embodiment of the present invention. FIG. 7A to FIG. 7E are cross-sectional views showing the circuit board manufacturing process in the first embodiment of the present invention. FIG. 8 is a plan perspective view of a circuit board according to the second embodiment of the present invention. FIG. 9 is a cross-sectional view taken along the line IX-IX of FIG. 8 of the circuit board according to the second embodiment of the present invention. FIG. 10 is a diagram for explaining the positional relationship between the through holes, the electronic components, and the wirings of the circuit board according to the second embodiment of the present invention, and is a plan view of the difficult expansion / contraction part. FIG. 11 is a diagram illustrating a circuit board according to the third embodiment of the present invention, FIG. 11A is a plan perspective view of the circuit board according to the third embodiment of the present invention, and FIG. FIG. 12 is a sectional view taken along line XIb-XIb in FIG. FIG. 12 is a diagram showing a circuit board according to the fourth embodiment of the present invention, FIG. 12A is a plan perspective view of the circuit board according to the fourth embodiment of the present invention, and FIG. It is sectional drawing along the XIIb-XIIb line | wire of Fig.12 (a).

  Embodiments of the present invention will be described below with reference to the drawings.

<< first embodiment >>
FIG. 1 is a plan perspective view of a circuit board according to the first embodiment of the present invention, FIG. 2 is a diagram showing a stretchable board according to the first embodiment of the present invention, and FIG. FIG. 2B is a perspective view taken along line IIb-IIb in FIG.

  As shown in FIG. 1, the circuit board 1 in this embodiment includes a stretchable substrate 20, a thin film transistor 40, and wiring 50. The circuit board 1 is used for, for example, an application in which the circuit board 1 is placed in close contact with the human body to follow the movement of the human body, or an application in which the circuit board 1 is arranged so as to cover the surface of an object having a complicated shape. The “circuit board 1” in the present embodiment corresponds to an example of the “circuit board” of the present invention.

  As shown in FIGS. 2A and 2B, the stretchable substrate 20 includes a base material 21 and an island 30. In the example shown in FIGS. 2A and 2B, one island 30 is embedded in the base 21. However, the present invention is not limited to this, and the number of islands provided in the base Arrangement can be arbitrarily set.

  The base material 21 is formed in a sheet shape extending in a plane (X direction and Y direction in the figure). The base material 21 includes an upper main surface (hereinafter also simply referred to as “first main surface 22”) and a lower main surface (hereinafter simply referred to as “second main surface”) in the drawing. The main surfaces 22 and 23 are formed so as to be substantially parallel to each other. Such a stretchable substrate 20 can be stretched in the direction along the XY plane in the drawing (hereinafter also simply referred to as “stretching direction”).

  The base material 21 is made of a material having a Young's modulus of about 0.1 [MPa] to 10 [MPa]. Specific examples of the material constituting the base material 21 include, for example, elastomers such as silicone rubber, urethane rubber, fluoro rubber, natural rubber, acrylic rubber, and thermoplastic elastomer.

  The island 30 has a flat plate shape, and the entire surface of the island 30 is covered with the base material 21 so that the island 30 is embedded in the base material 21 without being exposed to the outside. The island 30 includes a main surface on the upper side of the island 30 (hereinafter also simply referred to as “third main surface 31”) and a main surface on the lower side of the island 30 in the drawing (hereinafter simply referred to as “first” 4 ”, and these main surfaces 31 and 32 are formed so as to be substantially parallel to each other. The shape of the island 30 is not particularly limited to the above, and may be, for example, a disk shape.

  The island 30 is made of a material that is relatively hard with respect to the base material 21. For this reason, even if the base material 21 is arbitrarily expanded and contracted, the shape of the island 30 hardly changes. Thereby, the stretchable substrate 20 has stretchability and can hold and fix other members on the island 30 that does not change shape by using an appropriate fixing means.

Specifically, such an island 30 is made of a material having a relatively large Young's modulus (E ₂ ) relative to the Young's modulus (E ₁ ) of the material constituting the base material 21 (E ₂ > E ₁ ), preferably, a material having a Young's modulus that is twice or more the Young's modulus of the material constituting the substrate 21 (E ₂ ≧ 2 × E ₁ ).

  Moreover, as a specific example of the material which comprises the island 30, what added the filler to the same elastomer as the elastomer which comprises the base material 21 can be illustrated, for example. Examples of the filler include silica powder, carbon black, and alumina powder. In addition, although the addition amount of a filler is suitably set according to the desired Young's modulus, it is preferable that it is 1 to 60 weight% with respect to the total weight of the material of the said island.

  In this way, by adding a filler to the same elastomer as that constituting the base material 21, the Young's modulus of the island 30 becomes relatively larger than the Young's modulus of the base material 21. The island 30 can be made relatively hard.

  In addition, while having the same elastomer as the main component constituting the base material 21 as a main component, increasing the blending ratio of the crosslinking agent than the base material 21, or increasing the blending ratio of the curing agent than the base material 21, The Young's modulus of the island 30 may be larger than the Young's modulus of the base material 21.

  Moreover, the adhesiveness of the base material 21 and the island 30 can be improved by configuring the island 30 with a material mainly composed of the same elastomer as that of the base material 21. Thereby, peeling of the island 30 from the base material 21 accompanying repetition of expansion and contraction of the elastic substrate 20 can be suppressed.

  In addition, as long as the Young's modulus of the material which comprises the island 30 is relatively larger than the Young's modulus of the material which comprises the base material 21, the material which comprises the island 30 will not be specifically limited. For example, the island 30 may be made of an elastomer different from the elastomer constituting the base material 21, a resin material other than the elastomer, ceramics, or glass. Further, when the island 30 may have conductivity, the island 30 may be made of a metal material.

  Such a substrate 21 preferably has a thickness of 10 [μm] to 100 [μm], and the island 30 preferably has a thickness of 10 [μm] to 100 [μm].

  The covering portion 24 is stacked on the third and fourth main surfaces 31 and 32 of the island 30 in the present embodiment. The covering portion 24 is formed by the base material 21 covering the entire surfaces of the third and fourth main surfaces 31 and 32. Thus, also in the region overlapping with the island 30 in a plan view, the covering portion 24 constituted by the extendable base material 21 covers the third and fourth main surfaces 31 and 32, so that the expansion and contraction is achieved. It is suppressed that the elasticity in the expansion / contraction direction of the conductive substrate 20 is lowered.

   Further, as shown in FIGS. 2A and 2B, one first through hole 33 is formed in the island 30. The first through hole 33 has a substantially circular opening, penetrates between the third and fourth main surfaces 31 and 32 of the island 30 so as to have a uniform diameter, and extends in the vertical direction. It is formed along (Z direction in the figure). In addition, a part of the covering portion 24 protrudes inside the first through hole 33 so as to be in contact with the inner surface of the first through hole 33. Then, the protruding portion of the covering portion 24 extends along the first through hole 33, so that the covering is laminated on both main surfaces 31 and 32 of the island 30 through the first through hole 33. The parts 24 communicate with each other. As a result, the base material 21 is filled in the first through hole 33.

  In the present embodiment, the inside of the first through-hole 33 is completely filled with the base material 21, but at least a part of the first through-hole 33 is formed by projecting a part of the covering portion 24. If the base material 21 is filled so that it may contact with the inner surface of the said 1st through-hole 33, the filling amount of the base material 21 will not be specifically limited.

  Although not particularly limited, the diameter of the first through hole 33 is preferably 10 [μm] or more. Thereby, the base material 21 can be easily taken into the first through hole 33.

  In the present embodiment, the cross section of the first through hole 33 that is substantially orthogonal to the penetration direction of the first through hole 33 is point-symmetric with respect to the center (C1) of the cross section. The first through hole 33 is not limited to a circular shape. For example, the first through-hole 33 has an n-gonal shape such as a quadrangle, a rhombus, or a hexagon (where n is an even number). Or a cross-sectional shape such as an ellipse.

  In the present embodiment, one first through hole 33 is formed for one island 30, but the present invention is not particularly limited to this. FIG. 3 is a view showing a first modification of the stretchable substrate in the first embodiment of the present invention, FIG. 3 (a) is a plan perspective view, and FIG. 3 (b) is FIG. 3 (a). FIG. 3 is a cross-sectional view taken along line IIIb-IIIb.

  For example, as shown in FIGS. 3A and 3B, a plurality of first through holes 33 may be formed. Five first through holes 33a to 33e are formed in the island 30A provided in the stretchable substrate 20A. Among these, the first through hole 33a is formed to have a center (C1) substantially the same as the center (C2) of the island 30A. In addition, first through holes 33b to 33e having a center are formed on a virtual circle having the same center as the center of the first through hole 33a. And these through-holes 33b-33e are arrange | positioned so that it may become substantially equal intervals along the circumferential direction of the said virtual circle.

  Thus, it is preferable that the plurality of first through holes 33 are formed so as to be point-symmetric with respect to the center (C2) of the island 30A where the plurality of first through holes 33 are formed. . The plurality of first through holes 33 formed so as to be substantially point-symmetric with respect to the center (C2) of the island 30A is not particularly limited to the above.

  In the present embodiment, the first through hole 33 is formed to have a uniform diameter, but is not particularly limited thereto. Although not particularly limited, for example, the diameter of the first through hole 33 may be formed so as to gradually change between the third and fourth main surfaces 31 and 32 of the island 30.

  Further, in the present embodiment, the first through hole 33 is formed so as to penetrate between the third and fourth main surfaces 31 and 32 of the island 30 in the vertical direction, but is not particularly limited thereto. .

  The “stretchable substrate 20” in the present embodiment corresponds to an example of the “stretchable substrate” of the present invention, the “base material 21” in the present embodiment corresponds to an example of the “base material” of the present invention, The “island 30” in the present embodiment corresponds to an example of the “hard stretchable part” of the present invention, and the “third main surface 31” in the present embodiment corresponds to an example of the “first main surface” of the present invention. The “fourth main surface 32” in the present embodiment corresponds to an example of the “second main surface” in the present invention, and the “first through hole 33” in the present embodiment is the “through hole” in the present invention. Is equivalent to an example.

  In the above description, “center of first through-hole 33 (C1)” and “center of island 30 (C2)” indicate the position of the center of gravity in plan view. Here, the “centroid” means the center of mass when the inside of the contour in plan view is distributed with a uniform mass.

  4 is a cross-sectional view taken along line IV-IV in FIG. 1 of the circuit board according to the first embodiment of the present invention.

    The thin film transistor 40 is formed on the island 30 of the stretchable substrate 20, as shown in FIGS. In this manner, by providing the thin film transistor 40 on the island 30 that is relatively harder than the base material 21, it is possible to prevent the thin film transistor 40 from being destroyed as the base material 21 expands and contracts. Like the island 30, the thin film transistor 40 is covered with the base material 21 and is embedded in the base material 21 without being exposed to the outside. The “thin film transistor 40” in this embodiment corresponds to an example of “electronic component” and “thin film transistor” of the present invention.

  The thin film transistor 40 in the present embodiment is a thin film transistor having a bottom gate top contact type structure, and is provided on the island 30 so that a gate electrode 41, a gate insulating layer 42, and a semiconductor layer 43 are sequentially stacked. A source electrode 44 and a drain electrode 45 are provided in parallel on the gate insulating layer 42 and the semiconductor layer 43. A semiconductor layer 43 is interposed between the electrodes 44 and 45, thereby forming a predetermined interval.

  Note that an image display device using the thin film transistor 40 as a switching element can be obtained by connecting a pixel electrode to the secondary side of the drain electrode 45. Further, a pressure detection device can be obtained by connecting a pressure detection element to the primary side of the source electrode 44.

  The “gate electrode 41” in the present embodiment corresponds to an example of the “gate electrode” of the present invention, and the “source electrode 44” in the present embodiment corresponds to an example of the “source electrode” of the present invention. The “drain electrode 45” in the embodiment corresponds to an example of the “drain electrode” of the present invention.

  As shown in FIGS. 1 and 4, the wiring 50 includes a first wiring 60, a second wiring 70, and an insulating resin portion 80.

  The first wiring 60 includes first and second scanning wirings 61 and 65, first and second lead wirings 63 and 67, and first and second rising wirings 64 and 68. Yes. The second wiring 70 includes a third scanning wiring 71, a third extraction wiring 73, and a third rising wiring 74.

  The first scanning wiring 61 extends on the first main surface 22 of the base material 21 along the Y direction. From the first scanning wiring 61, a first lead wiring 63 is drawn along the X direction on the first main surface 22 of the substrate 21. The first lead wiring 63 is electrically connected to the first rising wiring 64 exposed at the first main surface 22 at one end.

  The first rising wiring 64 is formed inside a second through hole 241 that extends in the base member 21 along the vertical direction. As shown in FIG. 4, the first rising wiring 64 is electrically connected to the source electrode 44 at one end. Further, the other end portion is exposed at the first main surface 22 of the base material 21, and the source electrode (not shown) of another thin film transistor mounted on the circuit board 1 through the first scanning wiring 61. ) And are electrically connected.

  If the first lead-out wiring 63 and the first rising wiring 64 can electrically connect the source electrode 44 on the first main surface 22, the arrangement and path thereof are as follows. In particular, it is not limited to the above.

  The second scanning wiring 65 extends on the first main surface 22 of the base material 21 along the Y direction. From the second scanning wiring 65, a second lead wiring 67 is drawn on the first main surface 22 of the base member 21 along the X direction. The second lead wiring 67 is electrically connected to the second rising wiring 68 exposed at the first main surface 22 at one end.

  The second rising wiring 68 is formed inside a third through hole 242 that extends in the base material 21 along the vertical direction. As shown in FIG. 4, the second rising wiring 68 is electrically connected to the drain electrode 45 at one end. Further, the other end portion is exposed at the first main surface 22 of the base material 21, and the drain electrode (not shown) of another thin film transistor mounted on the circuit board 1 through the second scanning wiring 65. ) And are electrically connected.

  If the drain electrode 45 can be electrically connected on the first main surface 22, the arrangement and path of the second extraction wiring 67 and the second rising wiring 68 are as follows. In particular, it is not limited to the above.

  As shown in FIG. 1, the third scanning wiring 71 extends along the X direction on the first main surface 22 of the substrate 21. The third lead wiring 73 is formed on the third main surface 31 of the island 30 and is interposed between the island 30 and the thin film transistor 40. The third lead wiring 73 is connected to the gate electrode 41, and a part of the third lead wiring 73 extends from the gate electrode 41 toward the outside of the thin film transistor 40.

  Similar to the first and second rising lines 64 and 68, the third rising line 74 is drawn from the third scanning line 71 along the vertical direction. The third rising wiring 74 is formed inside a fourth through hole 243 extending along the vertical direction, and is electrically connected to the third lead wiring 73 at the end. Further, the other end is exposed at the first main surface 22 of the base material 21, and the gate electrode (not shown) of another thin film transistor mounted on the circuit board 1 through the third scanning wiring 71. ) And are electrically connected.

  If the gate electrode 41 can be electrically connected on the first main surface 22, the third lead wiring 73 and the third rising wiring 74 can be arranged and routed as follows. In particular, it is not limited to the above.

  The wiring 50 has elasticity to follow the expansion and contraction of the base material 21. As the wiring 50 which has a stretching property, what is disclosed by Unexamined-Japanese-Patent No. 2012-54192 can be used, for example.

  Specifically, the wiring 50 is formed, for example, by applying a conductive paste composed of an aqueous polyurethane dispersion and conductive particles and drying the conductive paste. By this drying, the polyurethane dispersion becomes a polyurethane elastomer containing no moisture, and the polyurethane elastomer functions as a binder for bonding the conductive particles, thereby imparting stretchability to the wiring 50.

  The “wiring 50” in the present embodiment corresponds to an example of the “wiring” of the present invention.

  The insulating resin portion 80 is provided on the first main surface 22 of the base material 21 in order to electrically insulate the first wiring 60 and the second wiring 70. As shown in FIG. 1, the resin insulating portion 80 includes an overlapping portion (intersection portion) of the first scanning wiring 61 and the third scanning wiring 71, the second scanning wiring 65, and the third scanning wiring in plan view. It is provided in the overlapping part of the scanning wiring 71. Thereby, since insulation is ensured in the overlapping portion, it is possible to suppress a short circuit failure of the wiring 50.

  FIG. 5 is a diagram for explaining the positional relationship between the through holes of the circuit board, the electronic components, and the wirings according to the first embodiment of the present invention, and is a plan view of the hardly stretchable part.

  In the present embodiment, the island 30 in the circuit board 1 has a mounting area 36 and a non-mounting area 37 on the third main surface 31 in plan view, as shown in FIG. The mounting region 36 is a region where at least one of the thin film transistor 40 or the wiring 50 is mounted in a plan view (a region surrounded by an alternate long and short dash line in the drawing), and the non-mounting region 37 is a thin film transistor 40 in the plan view. Alternatively, it is an area where none of the wiring 50 is mounted. In the present embodiment, the first through hole 33 is formed in the non-mounting region 37 of the island 30.

  Next, the manufacturing method of the island 30 in this embodiment is demonstrated, referring FIG. 6 (a)-FIG.6 (c).

  In the present embodiment, the thin film transistor 40 and the wiring 50 are formed on the third main surface 31 of the island 30 and the first through hole penetrating between the third and fourth main surfaces 31 and 32 of the island 30 is formed. 33 is formed.

  The manufacturing method of the island 30 in the present embodiment includes an island forming step, a thin film transistor and a third lead wiring forming step, and a through hole forming step.

  First, in the island formation step, as shown in FIG. 6A, the island 30 is formed in a predetermined shape. Specifically, for example, the island 30 is cut to a dimension that allows the thin film transistor 40 and the first through hole 33 to be disposed.

  Next, in the formation process of the thin film transistor and the third lead wiring, as shown in FIG. 6B, the thin film transistor 40 and the third lead wiring 73 are formed on the island 30 prepared as described above.

  Specifically, first, the gate electrode 41 and the third lead wiring 73 are integrally formed at the same time by laminating aluminum (Al) on the island 30 by a sputtering method. In the present embodiment, aluminum (Al) is used as the conductive material that constitutes the gate electrode 41 and the third lead-out wiring 73. However, the present invention is not limited to this. For example, chromium (Cr), titanium (Ti), copper (Cu), molybdenum (Mo), tungsten (W), nickel (Ni), gold (Au), palladium (Pd), platinum (Pt), silver (Ag), tin (Sn), tantalum (Ta) or an alloy containing at least one of these may be used.

  Moreover, the manufacturing method of the gate electrode 41 and the 3rd extraction wiring 73 is not specifically limited above, For example, printing methods, such as a gravure printing method, a screen printing method, a gravure offset printing method, a chemical vapor deposition method, an electroless-plating method Alternatively, the gate electrode 41 and the third lead wiring 73 may be formed by an electrolytic plating method or a method combining them. Note that when the printing method as described above is used, the gate electrode 41 is formed by printing and curing a conductive ink on the island 30 instead of the conductive material. Examples of the conductive ink constituting the gate electrode 41 include those containing nano metal particles such as gold (Au), silver (Ag), and carbon (C).

  Next, the surface of the gate electrode 41 is oxidized using a plasma oxidation method or a UV oxidation method, and an aluminum oxide (AlOx) film is laminated to form the gate insulating layer 42. Next, a semiconductor layer 43 is formed by stacking DNTT (dinaphthothienothiophene) on the gate insulating layer 42 using a vacuum deposition method. In addition, the material which comprises the semiconductor layer 43 is not specifically limited above.

  Next, the source electrode 44 and the drain electrode 45 are formed by printing and curing silver (Ag) ink by a screen printing method. In addition, the manufacturing method of the source electrode 44 and the drain electrode 45 is not specifically limited to the above, You may comprise by the manufacturing method which was illustrated with the above-mentioned gate electrode 41. FIG.

  Next, in the through hole forming step, as shown in FIG. 6C, in the non-mounting region of the island 30, the island 30 is cut and penetrated along the vertical direction to form the first through hole 33. Form. The method for forming the first through hole 33 is not particularly limited to the above. For example, as a method of forming the first through hole 33, the first through hole 33 may be formed by penetrating the base material 21 by laser ablation.

  Next, a method for manufacturing the circuit board 1 in the present embodiment will be described with reference to FIGS. 7 (a) to 7 (e).

  The manufacturing method of the circuit board 1 in the present embodiment includes a lower base material forming step, an island placing step, an upper base material forming step, and a wiring forming step.

  First, in the lower base material forming step, the base material 25 is poured into the container 90 as shown in FIG. As this base material 25, the liquid elastomer which comprises the base material 21 mentioned above can be illustrated, for example. Then, the base material 25 poured into the container 90 is placed in a drying furnace (not shown), heated at 90 [° C.] for 4 minutes, and the base material 25 is cured, The lower base material 26b is formed.

  Next, in the island placing step, as shown in FIG. 7B, the island 30 provided with the thin film transistor 40 formed by the above-described manufacturing method is placed near the center on the lower substrate 26b.

  Next, in the upper base material forming step, the lower base material 26b on which the island 30 is placed is housed in the container 90 as shown in FIG. 7C in the same manner as the lower base material forming step. The base material 25 is poured into the container 90. At this time, since the base material 25 has high fluidity, the unevenness generated by placing the island 30 on the surface of the base material 25 or the island 30 generated by forming the thin film transistor 40. The unevenness is flattened.

  Then, as shown in FIG. 7 (d), the base material 25 poured into the container 90 is placed in a drying furnace (not shown), heated at 90 [° C.] for 4 minutes, The upper base material 26a is formed by curing the material 25. Thereby, the island 30 is embedded in the base material 21.

  Next, in the wiring formation step, as shown in FIG. 7E, first, the second to fourth through holes 241 to 243 (see FIG. 1 for the fourth through hole 243) are formed on the base material 21. It is formed by cutting along the vertical direction. In addition, the formation method of these through-holes 241-243 is not specifically limited to the above-mentioned, For example, you may form by penetrating the base material 21 by the ablation by a laser.

  Then, for example, the first to third rising wirings 64, 68, 74 (third rising wiring 74 are filled by filling aluminum (Al) in the second to fourth through holes 241 to 243 by sputtering. (See FIG. 1). Then, by printing and curing the above-described conductive paste on the first main surface 22 of the substrate 21 using a screen printing method, the first to third scanning wirings 61, 65, 71, First and second lead wires 63 and 67 are formed. In addition, the material which comprises the 1st-3rd rise wiring 64,68,74 and the 1st-3rd scanning wiring 61,65,71 is not specifically limited above. The manufacturing method of the first to third rising wirings 64, 68, 74 and the first to third scanning wirings 61, 65, 71 is not particularly limited to the above.

  At this time, the insulating resin portion 80 is formed by printing and curing a phenol resin ink by a gravure offset printing method. The resin material constituting the insulating resin portion 80 is not particularly limited to the above. Moreover, the printing method of the insulating resin part 80 is not specifically limited, For example, the screen printing method and the gravure printing method may be sufficient. Thus, the circuit board 1 is completed.

  In the above-described manufacturing method, the island 30 is embedded in the base material 21 by curing the liquid elastomer, but the invention is not particularly limited thereto. For example, the island 30 may be embedded in the base material 21 by disposing a raw material elastomer and island mixed with a crosslinking agent in a mold and performing vulcanization molding treatment.

  Next, the operation of the circuit board 1 and the stretchable board 20 in this embodiment will be described.

  In the conventional stretchable substrate, when the stretchable substrate is stretched, high shear stress is generated at the interface parallel to the stretch direction due to the difference in Young's modulus between the base material and the island. As a result, there is a problem that the island may peel from the base material at the interface parallel to the expansion and contraction direction of the base material and the island.

  On the other hand, in the present embodiment, the island 30 has a first through hole 33 that penetrates an interface (third and fourth main surfaces 31 and 32) parallel to the expansion and contraction direction of the island 30. . As described above, in the third and fourth main surfaces 31 and 32, the first through holes 33 are formed on the main surfaces 31 and 32 from the entire area of the third and fourth main surfaces 31 and 32. The area of the opening to be opened is subtracted. As a result, the contact area between the base material 21 and the island 30 is reduced on both main surfaces 31 and 32 of the island 30.

  Moreover, since the inside of the first through-hole 33 is filled with the base material 21 and the inner surface of the first through-hole 33 and the base material 21 are bonded, the inner surface of the first through-hole 33 and The contact area with the base material 21 increases. For this reason, the island 30 is easily extended by the amount of the first through hole 33 provided, and the base material that is in contact with the inner surface of the first through hole 33 when the elastic substrate 20 is expanded or contracted. 21 easily expands and contracts in the same direction as the stretch direction of the stretchable substrate 20. Accordingly, shear stress is generated on the inner surface of the first through-hole 33 along the direction perpendicular to the direction of expansion and contraction of the stretchable substrate 20. Therefore, the shear stress applied to the third and fourth main surfaces 31 and 32 is reduced by the shear stress generated on the inner surface of the first through hole 33. Thereby, it can suppress that the island 30 peels from the base material 21 along the expansion / contraction direction of the elastic substrate 20.

  Furthermore, in this embodiment, the covering portion 24 covers the third and fourth main surfaces 31 and 32 of the island 30, and the island 30 is embedded in the base material 21. As described above, since the island 30 does not penetrate between the first and second main surfaces 22 and 23 of the base material 21, it is possible to prevent the stretchability of the stretchable substrate 20 from being lowered.

  In the present embodiment, the first through-hole 33 is always point-symmetric with respect to the center (C1) of the cross-section, the cross-section being substantially orthogonal to the through-direction of the first through-hole 33. It is formed to become. In this case, since the isotropic property in the radial direction of the first through-hole 33 is ensured in plan view, the shear generated between the base material 21 and the island 30 with respect to the expansion / contraction direction of the elastic substrate 20. The stress can be applied uniformly. Thereby, it can suppress further that the island 30 peels from the base material 21. FIG.

  Further, in the present embodiment, a plurality of first through holes 33 are formed for one island 30, so that the base material 21 and the third main surface 31, 32 of the island 30, The contact area with the island 30 can be further reduced. Thereby, it can suppress further that the island 30 peels from the base material 21. FIG.

  Further, in the present embodiment, the plurality of first through holes 33 are formed so as to be point-symmetric with respect to the center (C2) of the island 30A where the plurality of first through holes 33 are formed. In the third and fourth main surfaces 31 and 32 of the island 30, the contact area between the base material 21 and the island 30A can be further reduced, and the isotropic property of the island 30A can be ensured in plan view. it can. Thereby, it can suppress further that the island 30A peels from the base material 21. FIG.

  In the present embodiment, the first through hole 33 is formed on the island 30 so that the thin film transistor 40 and the wiring 50 do not overlap with the first through hole 33 in plan view. Accordingly, it is possible to suppress the island 30 from being peeled off from the base material 21, and it is possible to hold and fix the thin film transistor 40 and the wiring 50 more firmly on the island 30.

<< Second Embodiment >>
8 and 9 are diagrams showing a circuit board according to the second embodiment of the present invention, FIG. 8 is a plan perspective view of the circuit board according to the second embodiment of the present invention, and FIG. It is sectional drawing along the IX-IX line.

  As shown in FIGS. 8 and 9, the circuit board 10 in the present embodiment includes a stretchable substrate 200, m × n thin film transistors 40, and wirings 500. In this embodiment, a plurality of thin film transistors 40 (four in this embodiment) are formed on the island 300, and a wiring 500 is formed so as to correspond to the plurality of thin film transistors 40. This is different from the first embodiment.

  As shown in FIG. 8, m × n (m and n are natural numbers) thin film transistors 40 are incorporated in the circuit board 10. The m × n thin film transistors 40 are arranged in m rows and n columns along the X direction and the Y direction on one island 300 in which a plurality of first through holes 33 (five in this embodiment) are formed. They are arranged in a matrix.

  In the present embodiment, the plurality of first through holes 33 are formed in the island 300. However, the present invention is not particularly limited thereto, and at least one first through hole 33 is formed in the island 300. It only has to be done.

  As shown in FIGS. 8 and 9, the wiring 500 includes a first wiring 600, a second wiring 700, and an insulating resin portion 800.

  The first wiring 600 includes first and fourth scanning wirings 610 and 62, a first extraction wiring 630, a first rising wiring 640, second and fifth scanning wirings 650 and 66, A second lead wiring 670 and a second rising wiring 680 are provided. The second wiring 700 includes third and sixth scanning wirings 710 and 72, a third extraction wiring 730, and a third rising wiring 740.

  The first and second scanning wirings 610 and 650 extend on the first main surface 22 of the base member 21 along the X direction. Also. The fourth and fifth scanning lines 62 and 66 extend on the third main surface 31 of the island 300 along the Y direction. The fourth and fifth scanning wirings 62 and 66 are formed in n numbers, and these are arranged along the X direction. The n fourth and fifth scanning wirings 62 and 66 are arranged so as to be substantially parallel to each other at equal intervals.

  The first and second lead wirings 630 and 670 extend on the third main surface 31 of the island 300 along the X direction. The m first and second lead wires 630 and 670 are formed so as to correspond to the m thin film transistors 40 arranged in the Y direction. The m first extraction wirings 630 are extracted from one fourth scanning wiring 62 and are electrically connected to the source electrode 44 at one end. Further, the m second extraction wirings 670 are extracted from one fifth scanning wiring 66 and are electrically connected to the drain electrode 45 at one end.

  The first rising wiring 640 extends in the base material 21 along the vertical direction, and is electrically connected to the fourth scanning wiring 62 on the third main surface 31 of the island 30. The n first rising wirings 640 are formed so as to correspond to the n fourth scanning wirings 62, and the n first rising wirings 640 are formed as one first scanning wiring 610. Has been pulled from.

  The second rising wiring 680 extends in the vertical direction in the base material 21 and is electrically connected to the fifth scanning wiring 66 on the third main surface 31 of the island 30. The n second rising lines 680 are formed so as to correspond to the n fifth scanning lines 66, and the n second rising lines 680 are formed as one second scanning line 650. Has been pulled from.

  The third scanning wiring 710 extends on the first main surface 22 of the base material 21 along the Y direction. The sixth scanning wiring 72 extends on the third main surface 31 of the island 300 along the X direction. The sixth scan lines 72 are formed in m pieces, and these are arranged along the Y direction. The m sixth scanning wirings 72 are arranged so as to be substantially parallel to each other at equal intervals.

  The third lead wiring 730 extends on the third main surface 31 of the island 300 along the Y direction. The third lead lines 730 are formed so as to correspond to the n thin film transistors 40 arranged in the X direction, and the n third lead lines 730 are one first line. 6 from the scanning wiring 72. One end portion is electrically connected to the gate electrode 41.

  The third rising wiring 740 extends in the base material 21 along the vertical direction, and is electrically connected to the sixth scanning wiring 72 on the third main surface 31 of the island 30. The m third rising wirings 740 are formed so as to correspond to the m sixth scanning wirings 72, and the m third rising wirings 740 are formed as one third scanning wiring 710. Has been pulled from.

  As a material constituting such a wiring 500, the same material as that of the first embodiment can be exemplified.

  The “fourth scanning wiring 62” and the “fifth scanning wiring 66” in the present embodiment correspond to an example of the “first scanning wiring” in the present invention, and the “sixth scanning wiring in the present embodiment”. 72 ”corresponds to an example of“ second scanning wiring ”of the present invention,“ X direction ”in the present embodiment corresponds to an example of“ first direction ”of the present invention, and“ Y direction ”in the present embodiment. "Corresponds to an example of" second direction "of the present invention.

  The resin insulation part 800 is formed in the overlapping part of the first and second wirings 600 and 700. Specifically, as illustrated in FIG. 8, the insulating resin portion 800 includes the overlapping portion of the first scanning wiring 610 and the third scanning wiring 710, the second scanning wiring 650, and the third scanning wiring in the plan view. The overlapping portion of the scanning wiring 710, the overlapping portion of the first extraction wiring 630 and the third extraction wiring 730, the overlapping portion of the second extraction wiring 670 and the third extraction wiring 730, and the fourth scanning wiring 62. And the overlapping portion of the sixth scanning wiring 72 and the overlapping portion of the fifth scanning wiring 66 and the sixth scanning wiring 72.

  FIG. 10 is a diagram for explaining the positional relationship among the through holes, the electronic components, and the wirings of the circuit board according to the second embodiment of the present invention, and is a plan view of the hard stretchable part.

  In the present embodiment, as in the first embodiment, the island 300 in the circuit board 10 has a mounting region 360 and a non-mounting region 370 on the third main surface 31 in a plan view as shown in FIG. ,have. A first through hole 33 is formed in the non-mounting region 370 of the island 300.

  Next, the operation of the circuit board 10 and the stretchable board 200 in this embodiment will be described.

  With respect to the circuit board 10 and the stretchable substrate 200 in the present embodiment, the same effects as the circuit board 1 and the stretchable substrate 20 in the first embodiment can be obtained.

  Further, in the present embodiment, a plurality of thin film transistors 40 are arranged on one island 300. Thus, it is not necessary to form a plurality of islands so as to correspond to a plurality of thin film transistors. Thereby, the manufacturing process of the elastic substrate 200 can be simplified, and as a result, the increase in the manufacturing cost of the elastic substrate 200 and the circuit board 10 can be suppressed.

<< Third Embodiment >>
FIG. 11 is a diagram illustrating a circuit board according to the third embodiment of the present invention, FIG. 11A is a plan perspective view of the circuit board according to the third embodiment of the present invention, and FIG. FIG. 12 is a cross-sectional view taken along line XIIIb-XIIIb in FIG.

  As shown in FIGS. 11A and 11B, the circuit board 11 in this embodiment includes a stretchable substrate 201, a thin film transistor 400, and a wiring 501. In the present embodiment, the island 301 is exposed to the outside from the first main surface 22 of the substrate 21, the thin film transistor 400 is exposed to the outside, and the first to third rising wirings 64, It differs from the first embodiment in that 68 and 74 are not formed.

  The stretchable substrate 201 in the present embodiment includes a base material 21 and an island 301 as shown in FIGS. 11 (a) and 11 (b). The island 301 is embedded in the base material 21 so that the third main surface 31 is exposed from the base material 21. The third main surface 31 is located substantially on the same plane as the first main surface 22 of the base material 21.

  Thus, in the island 301 in the present embodiment, the third main surface 31 side is not covered with the covering portion 24, and the fourth main surface 32 side is covered with the covering portion 24. As described above, since the covering portion 24 covers at least one of the third and fourth main surfaces 31 and 32, it is suppressed that the stretchability of the stretchable substrate 20 is lowered as in the first embodiment. Has been.

  A first through hole 330 is formed in the island 301. The first through-hole 330 opens at the third main surface 31 of the island at one end. And with the 3rd main surface 31 exposed from the base material 21, the said 1st through-hole 330 is also exposed toward the exterior. On the fourth main surface 32 side, a part of the covering portion 24 protrudes toward the inside of the first through hole 330 so as to contact the inner surface of the first through hole 330. And the base material 21 is exposed from the 3rd main surface 31 side because the part which the coating | coated part 24 protruded extended along the 1st through-hole 330. As shown in FIG. As a result, the substrate 21 is filled in the first through hole 330.

  In the present embodiment, the island 301 is provided so that the third main surface 31 is located substantially on the same plane as the first main surface 22 of the base material 21, but is not particularly limited thereto. Not. Although not particularly illustrated, for example, the island 301 may be provided so as to protrude upward with respect to the first main surface 22 of the base material 21.

  The thin film transistor 400 is formed on the third main surface 31 of the island 301, as shown in FIGS. 11 (a) and 11 (b). In this island 301, the thin film transistor 400 is exposed to the outside as the third main surface 31 is exposed from the base material 21.

  The wiring 501 includes a first wiring 601, a second wiring 701, and an insulating resin portion 801.

  The first wiring 601 has first and second scanning wirings 611 and 651 and first and second lead wirings 631 and 671. The second wiring 701 includes a third scanning wiring 711 and a third lead wiring 731.

  The first and second scanning wirings 611 and 651 are formed along the Y direction over the first main surface 22 of the base material 21 and the third main surface 31 of the island 301. From the first scanning wiring 611, a first extraction wiring 631 is drawn out on the third main surface 31 of the island 301 along the X direction, and is electrically connected to the source electrode 44 at one end. doing. Further, a second lead wiring 671 is drawn from the second scanning wiring 651 along the X direction on the third main surface 31 of the island 301, and is electrically connected to the drain electrode 45 at one end. Connected to.

  The third scanning wiring 711 is formed along the X direction across the first main surface 22 of the base material 21 and the third main surface 31 of the island 301. From the third scanning wiring 711, a third lead wiring 731 is led out along the Y direction on the third main surface 31 of the island 301, and is electrically connected to the gate electrode 41 at one end. Connected.

  Four insulating resin portions 801 are formed on the third main surface 31 of the island 301. This insulating resin portion 801 is formed in the same manner as in the first embodiment.

  Next, the operation of the circuit board 11 and the stretchable board 201 in this embodiment will be described.

  With respect to the circuit board 11 and the stretchable substrate 201 in the present embodiment, the same effects as the circuit board and the stretchable substrate in the first embodiment can be obtained.

  In the island 301 in the present embodiment, the third main surface 31 side is not covered by the covering portion 24, and the fourth main surface 32 side is covered by the covering portion 24. As described above, since the covering portion 24 covers at least one of the third and fourth main surfaces 31 and 32, it is possible to prevent the stretchability of the stretchable substrate 20 from being lowered as in the first embodiment. can do.

  Further, in the present embodiment, the circuit board 11 does not need to form the rising wirings 64, 68, 74, and the formation of the wiring 501 can be simplified. Thereby, it is possible to further suppress an increase in manufacturing costs of the stretchable substrate 201 and the circuit board 11.

<< Fourth embodiment >>
FIG. 12 is a diagram showing a circuit board according to the fourth embodiment of the present invention, FIG. 12A is a plan perspective view of the circuit board according to the fourth embodiment of the present invention, and FIG. FIG. 13 is a cross-sectional view taken along line XVb-XVb in FIG.

  As shown in FIGS. 12A and 12B, the circuit board 12 in the present embodiment includes the stretchable substrate 20, the thin film transistor 401, and the wiring 502. This embodiment is different from the first embodiment in that the thin film transistor 401 is exposed to the outside and the rising wirings 64, 68, and 74 are not formed. In addition, since the elastic substrate 20 which comprises the circuit board 12 in 3rd Embodiment is the same as each structure with which 1st Embodiment is provided, description is abbreviate | omitted.

  In the present embodiment, the thin film transistor 401 is formed on the first main surface 22 of the base material 21 and embedded in the base material 21 as shown in FIGS. 12 (a) and 12 (b). It is exposed outside.

  As shown in FIGS. 12A and 12B, the wiring 502 includes a first wiring 602, a second wiring 702, and an insulating resin portion 802.

  The first wiring 602 includes first and second scanning wirings 612 and 652 and first and second lead wirings 632 and 672. The second wiring 702 includes a third scanning wiring 712 and a third extraction wiring 732.

  The first and second wirings 601 and 701 described in the third embodiment except that the first and second wirings 602 and 702 are formed on the first main surface 22 of the substrate 21. Since it has the same configuration as each of the above, description thereof is omitted.

  Four insulating resin portions 802 are formed on the first main surface 22 of the substrate 21. The insulating resin portion 802 is formed in the same manner as in the first embodiment.

  Next, the operation of the circuit board 12 and the stretchable board 20 in this embodiment will be described.

  With respect to the circuit board 12 and the stretchable board 20 in the present embodiment, the same effects as the circuit board in the first embodiment can be obtained.

  Furthermore, in this embodiment, the circuit board 12 does not need to form the rising wirings 64, 68, and 74, and the formation of the wiring 502 can be simplified. Thereby, it is possible to further suppress an increase in manufacturing cost of the circuit board 12.

  The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1,10-12 ... Circuit board 20, 200, 201 ... Elastic substrate 21 ... Base material 22 ... 1st main surface 23 ... 2nd main surface 24 ... Covering Part 30, 300, 301 ... Island 31 ... Third main surface 32 ... Fourth main surface 33, 330 ... First through hole 36, 360 ... Mounting region 37, 370 ... Non-mounting area 40, 400, 401 ... Thin film transistor 50, 500 to 502 ... Wiring 60, 600 to 602 ... First wiring 70, 700 to 702 ... Second wiring 80, 800-802 ... Resin insulation part 90 ... Container

Claims (6)

A substrate having a stretchability, are embedded prior Kimoto material, a stretchable base plate and a relatively rigid flame stretch unit than the substrate,
At least one electronic component provided on the base material so as to be provided on the hard stretchable part or overlapping the hard stretchable part;
Provided on the difficult stretchable part, or at least one wiring provided on the base material so as to overlap the difficult stretchable part ,
The difficult stretchable part has a through-hole penetrating the first and second main surfaces of the difficult stretchable part,
The base material has a covering portion that covers at least one of the first main surface and the second main surface;
The circuit board, wherein the through hole is filled so that at least a part of the through hole protrudes and the base material contacts the inner surface of the through hole. . The circuit board according to claim 1,
The circuit board , wherein the hard stretchable part is embedded in the base material so that the whole surface of the hard stretchable part is covered with the base material. The circuit board according to claim 1 or 2,
The circuit board , wherein the through hole has a shape such that a cross section substantially perpendicular to a through direction of the through hole is point-symmetric with respect to a center of the cross section. The circuit board according to any one of claims 1 to 3,
The circuit board , wherein the difficult expansion / contraction part has a plurality of the through holes. The circuit board according to claim 4,
The circuit board , wherein the plurality of through holes are arranged so as to be point-symmetric with respect to the center of the difficult expansion / contraction part. The circuit board according to any one of claims 1 to 5 ,
The plurality of electronic components are m × n thin film transistors arranged in a matrix of m rows and n columns along the first and second directions,
The wiring is
N first scan lines electrically connecting source electrodes or drain electrodes of the m thin film transistors arranged along the first direction;
M second scanning wirings that are electrically insulated from the first scanning wirings and electrically connect the gate electrodes of the n thin film transistors arranged along the second direction. And a circuit board comprising:

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