Wiring board and method for manufacturing wiring board

TWI934815BActive Publication Date: 2026-08-01DAI NIPPON PRINTING CO LTD
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Patent Information

Authority / Receiving Office
TW · TW
Patent Type
Patents
Current Assignee / Owner
Filing Date
2018-11-29
Publication Date
2026-08-01

AI Technical Summary

Technical Problem

Mobile devices face challenges with limited space for multiple antennas, leading to unsatisfactory radio wave sensitivity and uneven current distribution in thin-film antennas, making them difficult to integrate effectively in miniaturized devices.

Method used

A wiring substrate with transparent first and second wirings on a transparent substrate, featuring recessed side surfaces and varying line widths, and potentially including dummy patterns, to enhance conductivity and uniform current distribution.

Benefits of technology

The solution improves antenna characteristics by ensuring uniform current distribution and reducing visibility of the antenna patterns, enhancing radio wave transmission and reception while maintaining transparency.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

A wiring substrate includes: a substrate having transparency; a plurality of first wirings disposed on the upper surface of the substrate, extending in a first direction, and having a back side adjoining the substrate and a front side facing the opposite side of the back side; and second wirings disposed on the upper surface of the substrate, extending in a second direction intersecting the first direction, and having a back side adjoining the substrate and a front side facing the opposite side of the back side. Each first wiring has a pair of side surfaces extending in the first direction and adjacent to the back side of the first wiring, and each pair of side surfaces of the second wiring is recessed inwards. Each second wiring has a pair of side surfaces extending in the second direction and adjacent to the back side of the second wiring, and each pair of side surfaces of the second wiring is recessed inwards.
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Description

Technical Field

[0001] Invention Field This disclosure relates to a wiring board and a method for manufacturing the wiring board. Prior Technology

[0002] Background of the Invention Currently, mobile devices such as smartphones and tablets are constantly evolving towards higher performance, smaller size, thinner profiles, and lighter weights. Because these mobile devices use multiple communication frequency bands, they require multiple antennas to accommodate those bands. For example, mobile devices may contain multiple antennas, including antennas for telephone communication, WiFi (Wireless Fidelity), 3G, 4G, LTE (Long Term Evolution), Bluetooth, and NFC (Near Field Communication). However, with the miniaturization of mobile devices, the space available for antennas is limited, and the freedom of antenna design has gradually decreased. Furthermore, because the antennas are housed within a limited space, the radio wave sensitivity is not always satisfactory.

[0003] Therefore, a thin-film antenna that can be mounted on the display area of ​​a mobile terminal device has been developed. This thin-film antenna is a transparent antenna in which an antenna pattern is formed on a transparent substrate. The antenna pattern is formed by a mesh-like conductive mesh layer. The aforementioned mesh-like conductive mesh layer is composed of a conductor portion that forms an opaque conductive layer and a plurality of openings that form non-transparent conductive layers. Previous technical documents Patent documents

[0004] Patent Document 1: Japanese Patent Application Publication No. 2011-66610 Patent Document 2: Japanese Patent No. 5636735 Patent Document 3: Japanese Patent No. 5695947 Specification

[0005] One of the purposes of this disclosed embodiment is to provide a wiring board with improved conductivity and transparency that has radio wave transmission and reception functions, and a method for manufacturing the same.

[0006] Furthermore, in conventional thin-film antennas, although one or more grid antennas are mounted on a transparent substrate, there are both areas with antenna patterns and areas without antenna patterns on the transparent substrate. In this case, because there are areas without antenna patterns, the areas with antenna patterns become more easily visible.

[0007] One of the objectives of this embodiment is to provide a wiring board and a method for manufacturing the wiring board in a way that makes the antenna pattern area difficult to see.

[0008] Furthermore, in conventional thin-film antennas, one or more grid antennas are mounted on a transparent substrate. During transmission and reception using this grid antenna, there is a tendency for the current value to become higher towards the edge of the grid antenna and lower towards the center. Therefore, the current distribution in each grid antenna becomes uneven, making it difficult to fully improve the antenna characteristics.

[0009] This embodiment provides a wiring board and a method for manufacturing the wiring board that can make the current distribution in the antenna pattern area more uniform and improve the antenna characteristics. Summary of the Invention

[0010] Invention Summary The wiring substrate of one embodiment of this disclosure includes: a substrate having transparency; a plurality of first wirings disposed on the upper surface of the substrate and extending in a first direction, having a back side that is in contact with the substrate and a front side facing the opposite side of the back side; and a second wiring disposed on the upper surface of the substrate, extending in a second direction intersecting the first direction, having a back side that is in contact with the substrate and a front side facing the opposite side of the back side, wherein each first wiring has a pair of side surfaces that extend in the first direction and are adjacent to the back side of the first wiring, and the pair of side surfaces of the first wiring are recessed inwards respectively; and the second wiring has a pair of side surfaces that extend in the second direction and are adjacent to the back side of the second wiring, and the pair of side surfaces of the second wiring are recessed inwards respectively.

[0011] The wiring substrate of one embodiment of this disclosure includes: a substrate having transparency; a plurality of first wirings disposed on the upper surface of the substrate and extending in a first direction, having a back side that is in contact with the substrate and a front side facing the opposite side of the back side; and a second wiring disposed on the upper surface of the substrate and extending in a second direction intersecting the first direction, having a back side that is in contact with the substrate and a front side facing the opposite side of the back side, wherein each first wiring has a pair of side surfaces that extend in the first direction and are adjacent to the back side of the first wiring, and each second wiring has a pair of side surfaces that extend in the second direction and are adjacent to the back side of the second wiring, wherein one side surface of the first wiring and one side surface of the second wiring are continuously connected by a curved surface.

[0012] The wiring substrate of one embodiment of this disclosure includes: a substrate having transparency; a plurality of first wirings disposed on the upper surface of the substrate and extending in a first direction, having a back side that is in contact with the substrate and a front side facing the opposite side of the back side; and a second wiring disposed on the upper surface of the substrate and extending in a second direction that intersects the first direction, having a back side that is in contact with the substrate and a front side facing the opposite side of the back side, wherein the line width of the back side of the second wiring is smaller than the line width of the back side of the first wiring.

[0013] In one embodiment of the wiring substrate disclosed herein, the line width on the back side of the first wiring may be greater than the line width on the front side of the first wiring, and the line width on the back side of the second wiring may be greater than the line width on the front side of the second wiring.

[0014] In one embodiment of the wiring substrate disclosed herein, the second wiring may have a pair of side surfaces that extend in the second direction and are adjacent to the back surface of the second wiring. The angle between the front surface of the second wiring and each side surface is smaller than the external angle between the back surface of the second wiring and each side surface.

[0015] In one embodiment of the wiring substrate disclosed herein, the first wiring may have a pair of side surfaces that extend in the first direction and are adjacent to the back surface of the first wiring. The angle between the front surface of the first wiring and each side surface is smaller than the external angle between the back surface of the first wiring and each side surface.

[0016] In one embodiment of the wiring substrate disclosed herein, the intersection of the first wiring and the second wiring may include at least one of the corners formed by the upper surface of the substrate, the surface adjacent to the back surface of the first wiring, and the surface adjacent to the back surface of the second wiring, wherein the surfaces are continuously curved.

[0017] In one embodiment of the wiring board disclosed herein, radio wave transmission and reception functions may also be provided.

[0018] A method for manufacturing a wiring substrate according to one embodiment of the present disclosure includes the following steps: forming a conductive layer on the upper surface of a substrate; forming an insulating layer having a first trench extending in a first direction and a second trench extending in a second direction; forming a first conductor disposed in the first trench and a second conductor disposed in the second trench; removing the insulating layer; and removing the conductive layer to expose the upper surface of the substrate, thereby forming a first wiring and a second wiring by the first conductor and the second conductor.

[0019] In one embodiment of the present disclosure, the method for manufacturing a wiring substrate may also be as follows: the first wiring has a pair of side surfaces that extend in the first direction and are adjacent to the back surface of the first wiring, and the pair of side surfaces of the first wiring are recessed inwards respectively; the second wiring has a pair of side surfaces that extend in the second direction and are adjacent to the back surface of the second wiring, and the pair of side surfaces of the second wiring are recessed inwards respectively.

[0020] In one embodiment of the present disclosure, the method for manufacturing a wiring substrate may also be as follows: the first wiring has a pair of side surfaces that extend in the first direction and are adjacent to the back surface of the first wiring; the second wiring has a pair of side surfaces that extend in the second direction and are adjacent to the back surface of the second wiring; and one side surface of the first wiring and one side surface of the second wiring are continuously connected by a curved surface.

[0021] In one embodiment of the present disclosure, the manufacturing method of the wiring substrate may also be such that the line width on the back side of the second wiring is smaller than the line width on the back side of the first wiring.

[0022] In one embodiment of the present disclosure, the method for manufacturing a wiring substrate may also involve forming an insulating layer having the aforementioned first trench and the aforementioned second trench using an imprinting method.

[0023] In one embodiment of the present disclosure, the method for manufacturing a wiring substrate may be as follows: the method for forming the first wiring and the second wiring is to form the conductive layer by sputtering; to form the first wiring and the second wiring by electrolytic plating; and to remove the conductive layer by wet etching so that the upper surface of the substrate is exposed.

[0024] In one embodiment of the manufacturing method of the wiring substrate disclosed herein, the front sides of the aforementioned first wiring and the aforementioned second wiring may also be blackened.

[0025] According to the embodiments disclosed herein, a wiring substrate with improved conductivity and transparency and a method for manufacturing the same can be provided.

[0026] The wiring substrate of one embodiment of the present disclosure is a wiring substrate comprising: a substrate having transparency; a wiring pattern area disposed on the aforementioned substrate and including a plurality of wirings; and a dummy pattern area disposed around the aforementioned wiring pattern area and including a plurality of dummy wirings electrically independent of the aforementioned wirings. The aforementioned wiring pattern area and the aforementioned dummy pattern area are each composed of a repetition of a predetermined unit pattern shape. The unit pattern shape of the aforementioned dummy pattern area is a shape that is missing a portion of the unit pattern shape of the aforementioned wiring pattern area. An additional pattern separate from the aforementioned dummy wirings is disposed within the aforementioned dummy pattern area.

[0027] In one embodiment of the wiring substrate disclosed herein, the aforementioned dummy wiring may have a first dummy wiring portion and a second dummy wiring portion, and the first dummy wiring portion and the second dummy wiring portion are arranged separately from each other in the planar direction.

[0028] The wiring substrate of one embodiment of the present disclosure is a wiring substrate comprising: a substrate having transparency; a wiring pattern area disposed on the aforementioned substrate and including a plurality of wirings; and a dummy pattern area disposed around the aforementioned wiring pattern area and including a plurality of dummy wirings electrically independent of the aforementioned wirings, wherein the aforementioned dummy wirings are approximately L-shaped in a planar view.

[0029] In one embodiment of the wiring substrate disclosed herein, an additional pattern separate from the aforementioned dummy wiring may also be disposed within the aforementioned dummy pattern area.

[0030] One embodiment of the present disclosure discloses a wiring substrate comprising: a substrate having transparency; a wiring pattern region disposed on the substrate and including a plurality of wirings; and a dummy pattern region disposed around the wiring pattern region and including a plurality of dummy wirings electrically independent of the wirings, wherein the dummy wirings have a first dummy wiring portion and a second dummy wiring portion, and the first dummy wiring portion and the second dummy wiring portion are obliquely arranged relative to the wirings.

[0031] In one embodiment of the wiring substrate disclosed herein, the aperture ratio of the aforementioned dummy pattern region may be greater than that of the aforementioned wiring pattern region.

[0032] In one embodiment of the wiring board disclosed herein, the aperture ratio of the aforementioned dummy pattern area may be in the range of 87% or more and less than 100%.

[0033] In one embodiment of the wiring substrate disclosed herein, the difference between the aperture ratio of the aforementioned dummy pattern region and the aperture ratio of the aforementioned wiring pattern region may be 1% or less.

[0034] In one embodiment of the wiring substrate disclosed herein, the aforementioned wiring pattern area may also include a plurality of connecting wirings that connect the aforementioned plurality of wirings.

[0035] In one embodiment of the wiring board disclosed herein, radio wave transmission and reception functions may also be provided.

[0036] According to the implementation of this disclosure, the wiring pattern area can be made very difficult to see.

[0037] The wiring substrate of one embodiment of the present disclosure is a wiring substrate and includes: a substrate having transparency; an antenna pattern region disposed on the aforementioned substrate and including a plurality of antenna wirings having the function of an antenna, wherein the aperture ratio of the central portion of the aforementioned antenna pattern region in the width direction is higher than the aperture ratio of the edge portion of the aforementioned antenna pattern region in the width direction.

[0038] In one embodiment of the wiring substrate disclosed herein, the pitch of the plurality of antenna wirings in the central portion of the width direction of the aforementioned antenna pattern area may be wider than the pitch of the plurality of antenna wirings in the edge portion of the width direction of the aforementioned antenna pattern area.

[0039] In one embodiment of the wiring substrate disclosed herein, a gap may be formed in the center of the aforementioned antenna pattern area in the width direction, where no antenna wiring is provided.

[0040] In one embodiment of the wiring substrate disclosed herein, a dummy pattern area may be formed in the aforementioned gap, and the aforementioned dummy pattern area may include a plurality of dummy wirings that are electrically independent of the aforementioned antenna wirings.

[0041] In one embodiment of the wiring substrate disclosed herein, the aforementioned antenna pattern area may have a first pattern area and a second pattern area separated by the aforementioned gap, the first pattern area and the second pattern area being respectively disposed on the two edges of the aforementioned antenna pattern area in the width direction, and the first pattern area and the second pattern area being electrically connected to each other through the central pattern area.

[0042] In one embodiment of the wiring substrate disclosed herein, a connecting pattern area may be provided between the aforementioned central pattern area and the aforementioned first pattern area and second pattern area, wherein the aforementioned connecting pattern area has an inclined portion formed obliquely relative to the width direction of the aforementioned antenna pattern area.

[0043] In one embodiment of the wiring substrate disclosed herein, the aforementioned antenna pattern area may be electrically connected to the power supply section, and the length of the central portion of the aforementioned power supply section in the width direction is longer than the length of the edge portion of the aforementioned power supply section in the width direction.

[0044] The wiring substrate of one embodiment of the present disclosure is a wiring substrate comprising: a substrate having transparency; an antenna pattern area disposed on the aforementioned substrate and including a plurality of antenna wirings having the function of an antenna; and a power supply section electrically connected to the aforementioned antenna pattern area, wherein the length of the central portion of the aforementioned power supply section in the width direction is longer than the length of the edge portion of the aforementioned power supply section in the width direction.

[0045] The method for manufacturing a wiring substrate according to one embodiment of the present disclosure is a method for manufacturing a wiring substrate, comprising the following steps: a step of preparing a transparent substrate; and a step of forming an antenna pattern region on the aforementioned substrate, wherein the aforementioned antenna pattern region includes a plurality of antenna wirings that function as antennas, and the aperture ratio of the central portion of the aforementioned antenna pattern region in the width direction is higher than the aperture ratio of the edge portion of the aforementioned antenna pattern region in the width direction.

[0046] The method for manufacturing a wiring board according to one embodiment of the present disclosure is a method for manufacturing a wiring board, comprising the following steps: preparing a transparent substrate; and forming an antenna pattern area and a power supply section on the aforementioned substrate, wherein the aforementioned antenna pattern area includes a plurality of antenna wirings that function as antennas, the aforementioned power supply section is electrically connected to the aforementioned antenna pattern area, and the length of the central portion of the aforementioned power supply section in the width direction is longer than the length of the edge portion of the aforementioned power supply section in the width direction.

[0047] According to the embodiments disclosed herein, the current distribution in the antenna pattern area can be made more uniform, and the antenna characteristics can be improved. Simple Explanation of the Diagram

[0048] Figure 1 is a top view showing an example of a wiring board according to the first embodiment of the present disclosure. Figure 2 is a cross-sectional view showing an example of a wiring board according to the first embodiment of the present disclosure. Figure 3 is a cross-sectional view showing a first modified example of a wiring board according to the first embodiment of the present disclosure. Figure 4 is a cross-sectional view showing a second modified example of the wiring board according to the first embodiment of the present disclosure. Figure 5 is a cross-sectional view showing a third modified example of the wiring board according to the first embodiment of the present disclosure. Figure 6 is a cross-sectional view showing a fourth modified example of the wiring board according to the first embodiment of the present disclosure. Figure 7 is a top view showing a fifth modified example of the wiring board according to the first embodiment of the present disclosure. Figure 8 is a cross-sectional view showing a fifth modified example of the wiring board according to the first embodiment of the present disclosure. Figure 9 is a top view showing a sixth modified example of the wiring board according to the first embodiment of the present disclosure. Figure 10 is a cross-sectional view showing a sixth modified example of the wiring board according to the first embodiment of the present disclosure. Figure 11 is a cross-sectional view showing a method for manufacturing a wiring board according to the first embodiment of the present disclosure. Figure 12 is a cross-sectional view showing a method for manufacturing a wiring board according to the first embodiment of the present disclosure. Figure 13 is a cross-sectional view showing a modified example of the manufacturing method of the wiring board according to the first embodiment of the present disclosure. Figure 14 is a top view showing the wireless communication module of the first embodiment of this disclosure. Figure 15 is a top view showing a modified example of the wireless communication module according to the first embodiment of this disclosure. Figure 16 is an electron microscope (SEM) photograph of a cross-section of a wiring substrate according to the first embodiment of the present disclosure. Figure 17 is an electron microscope (SEM) photograph of a cross-section of the wiring substrate according to the first embodiment of the present disclosure. Figure 18 is a plan view showing the wiring board of the second embodiment. Figure 19 is an enlarged plan view of the wiring board of the second embodiment (an enlarged view of part XIX of Figure 18). Figure 20 is a cross-sectional view of the wiring board of the second embodiment (cross-sectional view of line XX-XX in Figure 19). Figure 21 is a cross-sectional view of the wiring board of the second embodiment (cross-sectional view of line XXI-XXI in Figure 19). Figure 22 is a cross-sectional view of the wiring board of the second embodiment (cross-sectional view of line XXII-XXII in Figure 19). Figures 23(a)-(h) are cross-sectional views showing the manufacturing method of the wiring board of the second embodiment. Figure 24 is a plan view of the image display device showing the second embodiment. Figure 25 is an enlarged plan view showing a modified example of the wiring board of the second embodiment (corresponding to Figure 19). Figure 26 is an enlarged plan view showing a modified example of the wiring board of the second embodiment (corresponding to Figure 19). Figure 27 is an enlarged plan view showing a modified example of the wiring board of the second embodiment (corresponding to Figure 19). Figure 28 is an enlarged plan view showing a modified example of the wiring board of the second embodiment (corresponding to Figure 19). Figure 29 is an enlarged plan view showing a modified example of the wiring board of the second embodiment. Figure 30 is an enlarged plan view showing a modified example of the wiring board of the second embodiment. Figure 31 is an enlarged plan view showing a modified example of the wiring board of the second embodiment. Figure 32 is an enlarged plan view showing a modified example of the wiring board of the second embodiment. Figure 33 is an enlarged plan view showing a modified example of the wiring board of the second embodiment. Figure 34 is an enlarged plan view showing a modified example of the wiring board of the second embodiment. Figure 35 is an enlarged plan view showing a modified example of the wiring board of the second embodiment. Figure 36 is an enlarged plan view showing a modified example of the wiring board of the second embodiment. Figure 37 is an enlarged plan view showing a modified example of the wiring board of the second embodiment. Figure 38 is a plan view showing the wiring board of the third embodiment. Figure 39 is an enlarged plan view of the wiring board of the third embodiment (an enlarged view of part XXXIX of Figure 38). Figures 40(a) and (b) are enlarged plan views of the wiring board of the third embodiment (enlarged views of the XLA portion and XLB portion of Figure 39, respectively). Figure 41 is a cross-sectional view of the wiring board of the third embodiment (cross-sectional view of line XLI-XLI in Figure 40). Figure 42 is a cross-sectional view of the wiring board of the third embodiment (cross-sectional view of line XLII-XLII in Figure 40). Figures 43(a)-(h) are cross-sectional views showing the manufacturing method of the wiring board of the third embodiment. Figure 44 is a plan view showing the image display device of the third embodiment. Figure 45 is an enlarged plan view of the wiring board of Modified Example 1 of the third embodiment (corresponding to Figure 39). Figure 46 is an enlarged plan view of the wiring board of Modified Example 2 of the third embodiment (corresponding to Figure 39). Figure 47 is an enlarged plan view of the wiring board of Modified Example 3 of the third embodiment (corresponding to Figure 39). Figure 48 is an enlarged plan view of the wiring board of Modified Example 4 of the third embodiment (corresponding to Figure 39). Figure 49 is an enlarged plan view of the wiring board of Modified Example 5 of the third embodiment (corresponding to Figure 39). Figure 50 is an enlarged plan view of the wiring board of Modified Example 6 of the third embodiment (corresponding to Figure 39). Figure 51 is a graph showing the current values ​​flowing in a uniform grid-shaped antenna pattern and a uniform plate-shaped antenna pattern in the third embodiment. Implementation

[0049] Forms for implementing the invention The figures shown below are schematic illustrations. Therefore, the sizes and shapes of the parts are appropriately exaggerated for ease of understanding. Furthermore, modifications can be made as appropriate without departing from the technical concept. Moreover, in the figures shown below, the same symbols are used for identical parts, and some detailed descriptions are omitted. Also, the dimensions and material names of the components described in this specification are merely examples of embodiments and are not limiting; they can be used selectively as appropriate. In this specification, specific terms used to describe shape or geometric conditions, such as parallel, orthogonal, or perpendicular, encompass not only precise meanings but also substantially the same conditions.

[0050] <First Implementation Form> The wiring board and its manufacturing method according to the first embodiment will now be described with reference to the drawings. However, the wiring board and its manufacturing method according to this embodiment can be implemented in many different forms and are not limited to the description of the embodiments shown below. Furthermore, in the drawings referred to in this embodiment, the same symbols are added to the same parts or parts with the same function, and repeated descriptions are omitted. Also, although terms such as "above" or "below" are used for ease of explanation, the vertical direction can be reversed. In this embodiment, the "front side" of the wiring refers to the side opposite to the side on which the substrate is provided when viewed from the wiring. The "back side" of the wiring refers to the side on which the substrate is provided when viewed from the wiring. The "side side" of the wiring refers to the side located between the "front side" and the "back side", and is the side facing the side relative to the long side direction of the wiring.

[0051] The structure of the wiring board 10 of this embodiment will be explained using Figure 1 or Figure 2.

[0052] [Structure of the wiring board] Figure 1 is a top view showing an example of a wiring substrate according to this embodiment. Figure 2 is a cross-sectional view showing an example of a wiring substrate according to this embodiment. Figure 2(A) is an enlarged cross-sectional view along link A-A' in Figure 1. Figure 2(B) is an enlarged cross-sectional view along link B-B' in Figure 1. As shown in Figure 1, the wiring substrate 10 includes a substrate 100, a first wiring 200, and a second wiring 300. The first wiring 200 and the second wiring 300 are disposed on the upper surface of the substrate 100. In this embodiment, although two first wirings 200 and one second wiring 300 are disposed, it is not limited to this. It is acceptable to have two or more first wirings 200 and one or more second wirings 300.

[0053] As shown in Figure 1, the planar shape of the first wiring 200 illustrates a shape in which multiple lines extend independently from the first side 102 of the substrate 100 toward the second side 104 (opposite to the first side 102, in the direction of the long side, the first direction, and the opposite direction of D2) of the first wiring 200. The planar shape of the second wiring 300 illustrates a shape in which one line extends toward a direction orthogonal to the direction of extension of the first wiring 200 (in the direction of the long side, the second direction, and the direction of D3 of the second wiring 300). That is, the second wiring 300 is orthogonal to two first wirings 200. Furthermore, the first wiring 200 is longer than the second wiring 300. When the wiring substrate 10 has radio wave transmission and reception functions, the first wiring 200 functions as an antenna, and the second wiring 300 functions as a connector to multiple first wirings 200. Each first wiring 200 extends in a direction corresponding to the antenna's frequency band (D2 direction), and each second wiring 300 extends in a direction orthogonal to the first wiring 200 (D3 direction). However, this shape is not a limitation; the planar shapes of the first wiring 200 and the second wiring 300 can be such that the plurality of lines intersect or connect. For example, the directions of the first wiring 200 and the second wiring 300 can intersect at an acute angle or an obtuse angle. When a plurality of first wirings 200 and second wirings 300 are arranged, these planar shapes become this repeating shape. That is, a regular grid or mesh shape can be formed by the first wiring 200 extending in the first direction and the second wiring 300 extending in the second direction. However, this is not a limitation; this repeating shape may not be uniform on the substrate 100. Also, although the substrate 100 is square in FIG. 1, it is not limited to this shape.

[0054] As shown in Figure 2(A), the first wiring 200 has a back surface (first surface) 201 that is in contact with the substrate 100, and a front surface (second surface) 202 facing the opposite side of the back surface 201. As shown in Figure 2(B), the second wiring 300 has a back surface (third surface) 303 that is in contact with the substrate 100, and a front surface (fourth surface) 304 facing the opposite side of the back surface 303. As shown in Figures 1, 2(A), and 2(B), the line width of the front surface 304 of the second wiring 300 is smaller than the line width of the front surface 202 of the first wiring 200. Furthermore, the line width of the back surface 303 of the second wiring 300 is smaller than the line width of the back surface 201 of the first wiring 200. Here, line width refers to the width parallel to the upper surface of the substrate 100 in a cross-section perpendicular to the direction in which the respective wiring extends. That is, in this embodiment, the line widths of the front side 202 and back side 201 of the first wiring 200 are respectively the lengths of the front side 202 and back side 201 in the D3 direction, and the line widths of the front side 304 and back side 303 of the second wiring 300 are respectively the lengths of the front side 304 and back side 303 in the D2 direction. By configuring the line widths of the front side 304 and back side 303 of the second wiring 300 to be smaller than the line widths of the front side 202 and back side 201 of the first wiring 200, the reliability of the first wiring 200, which has radio wave transmission and reception functions, can be maintained, and the visibility of the second wiring 300, which is prepared for the breakage of the first wiring 200, can be suppressed. Therefore, the conductivity and transparency of the wiring board 10 can be improved. Furthermore, not limited to the above, the line width of the front side 304 of the second wiring 300 can also be the same as the line width of the front side 202 of the first wiring 200. Furthermore, the wire width of the back side 303 of the second wiring 300 can also be the same as the wire width of the back side 201 of the first wiring 200.

[0055] As shown in Figure 2(A), the line width of the back side 201 of the first wiring 200 is larger than the line width of the front side 202 of the first wiring 200. As shown in Figure 2(B), the line width of the back side 303 of the second wiring 300 is larger than the line width of the front side 304 of the second wiring 300. By configuring the line width of the surface of the first wiring 200 and the second wiring 300 that is in contact with the substrate 100 to be larger than the line width of the surface facing the opposite side of the surface that is in contact with the substrate 100, the visibility of the first wiring 200 and the second wiring 300 when viewed in a planar manner in the D1 direction can be suppressed, and the adhesion between the substrate 100 and the first wiring 200 and the second wiring 300 can be improved. In addition, by increasing the area of ​​the cross-sections of the first wiring 200 and the second wiring 300 that intersect perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring board 10 can be improved.

[0056] As shown in Figure 2(A), the first wiring 200 has a pair of side surfaces (9th and 10th surfaces) 209 and 210, which extend along the direction of the first wiring 200 and are adjacent to the back surface 201. In the first wiring 200, the angles formed by the back surface 201 and one of the side surfaces 209, and the angles formed by the back surface 201 and the other side surface 210, are acute angles. In the first wiring 200, the angles formed by the back surface 201 and one of the side surfaces 209, and the angles formed by the back surface 201 and the other side surface 210, are the same. That is, in a cross-section perpendicular to the direction of extension of the first wiring 200, the first wiring 200 is linearly symmetrical about its extension direction (D2 direction).

[0057] As shown in Figure 2(B), the second wiring 300 has a pair of side surfaces (5th and 6th surfaces) 305 and 306, which extend along the direction of the second wiring 300 and are adjacent to the back surface 303. In the second wiring 300, the angles formed by the back surface 303 and one side surface 305, and the angles formed by the back surface 303 and the other side surface 306, are acute angles. In the second wiring 300, the angles formed by the back surface 303 and one side surface 305, and the angles formed by the back surface 303 and the other side surface 306, are the same. That is, in a cross-section perpendicular to the direction of extension of the second wiring 300, the second wiring 300 is linearly symmetrical about its extension direction (D3 direction).

[0058] The materials for the first wiring 200 and the second wiring 300 can be any conductive metallic materials. In this embodiment, the materials for the first wiring 200 and the second wiring 300 are copper, but this is not a limitation. The materials for the first wiring 200 and the second wiring 300 can be, for example, alloys of metallic materials including gold, silver, copper, platinum, tin, aluminum, iron, and nickel.

[0059] In this embodiment, the line width of the first wiring 200 (the line widths of the back side 201 and the front side 202) is not particularly limited as long as it meets the above conditions, and can be appropriately selected according to the application. For example, the line width of the first wiring 200 can be selected in the range of 0.1 μm or more and 5.0 μm or less. The line width of the second wiring 300 (the line widths of the back side 303 and the front side 304) is not particularly limited as long as it meets the above conditions, and can be appropriately selected according to the application. For example, the line width of the second wiring 300 can be selected in the range of 0.1 μm or more and 5.0 μm or less. The height of the first wiring 200 and the second wiring 300 is not particularly limited, and can be appropriately selected according to the application, and can be selected in the range of, for example, 0.1 μm or more and 5.0 μm or less.

[0060] Although not shown in the figure, the surfaces of the first wiring 200 and the second wiring 300, other than the surface in contact with the substrate 100, should be blackened. Specifically, for each of the first wiring 200 and the second wiring 300, the surface opposite to the surface in contact with the substrate 100 should be blackened. In this embodiment, the front surface 202 of the first wiring 200 and the front surface 304 of the second wiring 300 contain an oxide film of their respective wiring materials, namely copper oxide. However, this is not a limitation; preferably, the side surfaces 209 and 210 of the first wiring 200 and the side surfaces 305 and 306 of the second wiring 300 should also be blackened. Furthermore, as a method of blackening, known blackening methods such as oxidation, sulfidation, or blackening nickel plating of metal wiring can be used. Blackening can also be performed by forming a black resin coating. By blackening the front surfaces of the first wiring 200 and the second wiring 300, light reflection from the first wiring 200 and the second wiring 300 can be suppressed, and the absorption of external light and contrast of the wiring substrate 10 can be improved.

[0061] Although not shown in the figure, adhesion layers can be further disposed between the substrate 100 and the first wiring 200, and between the substrate 100 and the second wiring 300. Materials for the adhesion layers can include, for example, indium zinc oxide (IZO). By disposing adhesion layers between the substrate 100 and the first wiring 200, and between the substrate 100 and the second wiring 300, the adhesion between the substrate 100 and the first wiring 200, and between the substrate 100 and the second wiring 300, can be further improved.

[0062] The material of substrate 100 can be any material that is transparent in the visible light region and electrically insulating. In this embodiment, the material of substrate 100 is polyethylene terephthalate, but it is not limited to this. As the material of substrate 100, it is preferable to use organic insulating materials such as polyester resins such as polyethylene terephthalate, acrylic resins such as polymethyl methacrylate, polycarbonate resins, polyimide resins, or polyolefin resins such as cycloolefin polymers, or cellulose resins such as cellulose triacetate. Furthermore, as the material of substrate 100, glass, ceramics, etc., can be appropriately selected according to the application. Moreover, although the illustration shows an example of substrate 100 constructed by a single layer, it is not limited to this, and it can also be a structure composed of multiple substrates or layers. Furthermore, substrate 100 can be in the form of a thin film or a plate. Therefore, the thickness of substrate 100 is not particularly limited and can be appropriately selected according to the application.

[0063] As described above, in this embodiment of the wiring substrate 10, by configuring the line widths of the back side 303 and front side 304 of the second wiring 300 on the substrate 100 to be smaller than the line widths of the back side 201 and front side 202 of the first wiring 200, the reliability of the first wiring 200, which has radio wave transmission and reception functions, can be maintained, while suppressing the visibility of the second wiring 300 when viewed in a planar orientation in the D1 direction. Furthermore, by configuring the line width of the surface of the first wiring 200 and the second wiring 300 that is in contact with the substrate 100 to be larger than the surface facing the opposite side of the surface in contact with the substrate 100, the visibility of the first wiring 200 and the second wiring 300 when viewed in a planar orientation in the D1 direction can be suppressed, and the adhesion between the substrate 100 and the first wiring 200 and the second wiring 300 can be improved. Furthermore, by increasing the cross-sectional area of ​​the first wiring 200 and the second wiring 300 that intersect perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10 can be improved.

[0064] The wiring board 10 of this embodiment can be connected to a wireless communication circuit and mounted on a display device as a wireless communication module. By arranging the wiring board 100 on the upper surface of the display area so that the board 100 faces the display area of ​​the display device, the visibility of the first wiring 200 and the second wiring 300 when viewed in a planar orientation in the D1 direction can be suppressed. Therefore, a display device with a wiring board having improved transparency, reliability, and conductivity, and possessing radio wave transmission and reception functions, can be provided.

[0065] When the wiring board 10 has radio wave transmission and reception functions, it may also have any of the following functions: telephone antenna, WiFi antenna, 3G antenna, 4G antenna, LTE antenna, Bluetooth antenna, NFC antenna, etc. Alternatively, the wiring board 10 may not have radio wave transmission and reception functions. In this case, the wiring board 10 may still perform functions such as hovering (the function that allows the user to operate the display without directly touching it), fingerprint authentication, heater, and noise reduction (shielding).

[0066] Next, various modifications of the wiring board of this embodiment will be described.

[0067] <First Variation> In the configurations shown in Figures 1 and 2, in the cross-section perpendicular to the direction of extension of the second wiring 300, the second wiring 300 is linearly symmetrical about its long side direction (D3 direction). On the other hand, in this modified example, in the cross-section perpendicular to the direction of extension of the second wiring 300a, the second wiring 300a is asymmetrical about its long side direction (D3 direction).

[0068] The configuration of the wiring substrate 10a in this modified example will be explained using FIG3. Here, the configuration of the wiring substrate 10a in this modified example is the same as that of the wiring substrate 10 shown in FIGS. 1 and 2, except for the cross-sectional shape of the second wiring 300. Therefore, detailed descriptions of the parts identical to those shown in FIGS. 1 and 2 will be omitted.

[0069] [Structure of the wiring board] Figure 3 is a cross-sectional view showing one example of the wiring substrate of this modified example. Similar to the configuration shown in Figure 1, the wiring substrate 10a of this modified example includes a substrate 100a, a first wiring 200a, and a second wiring 300a. Figure 3(A) is an enlarged cross-sectional view along link A-A' in Figure 1. Figure 3(B) is an enlarged cross-sectional view along link B-B' in Figure 1.

[0070] As shown in Figure 3(A), the first wiring 200a has a back side (first surface) 201a that is in contact with the substrate 100a, and a front side (second surface) 202a facing the opposite side of the back side 201a. As shown in Figure 3(B), the second wiring 300a has a back side (third surface) 303a that is in contact with the substrate 100a, and a front side (fourth surface) 304a facing the opposite side of the back side 303a. As shown in Figures 3(A) and 3(B), the line width of the front side 304a of the second wiring 300a is smaller than the line width of the front side 202a of the first wiring 200a. Furthermore, the line width of the back side 303a of the second wiring 300a is smaller than the line width of the back side 201a of the first wiring 200a. By configuring the line widths of the front side 304a and back side 303a of the second wiring 300a to be smaller than the line widths of the front side 202a and back side 201a of the first wiring 200a, the reliability of the first wiring 200a, which has radio wave transmission and reception functions, can be maintained, while suppressing the visibility of the second wiring 300a prepared for potential breaks in the first wiring 200a. Therefore, the conductivity and transparency of the wiring substrate 10a can be improved.

[0071] As shown in Figure 3(A), the line width of the back surface 201a of the first wiring 200a is larger than the line width of the front surface 202a of the first wiring 200a. As shown in Figure 3(B), the line width of the back surface 303a of the second wiring 300a is larger than the line width of the front surface 304a of the second wiring 300a. By configuring the line width of the surface in contact with the substrate 100a in the first wiring 200a and the second wiring 300a to be larger than the line width of the surface facing the opposite side of the surface in contact with the substrate 100a, the visibility of the first wiring 200a and the second wiring 300a when viewed in a planar manner in the D1 direction can be suppressed, and the adhesion between the substrate 100a and the first wiring 200a and the second wiring 300a can be improved. Furthermore, by increasing the area of ​​the cross-sections of the first wiring 200a and the second wiring 300a that intersect perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10a can be improved.

[0072] As shown in Figure 3(A), the first wiring 200a has a pair of side surfaces (9th and 10th surfaces) 209a and 210a, which extend along the direction of the first wiring 200a and are adjacent to the back surface 201a. In the first wiring 200a, the angles formed by the back surface 201a and one of the side surfaces 209a, and the angles formed by the back surface 201a and the other side surface 210a, are acute angles. In the first wiring 200a, the angles formed by the back surface 201a and one of the side surfaces 209a, and the angles formed by the back surface 201a and the other side surface 210a, are the same. That is, in a cross-section perpendicular to the direction of extension of the first wiring 200a, the first wiring 200a is linearly symmetrical about its extension direction (D2 direction).

[0073] As shown in Figure 3(B), the second wiring 300a has a pair of side surfaces (the 5th and 6th surfaces) 305a and 306a, which extend in the direction of the second wiring 300a and are adjacent to the back surface 303a. In the second wiring 300a, the angles formed by the back surface 303a and one of the side surfaces 305a, and the angles formed by the back surface 303a and the other side surface 306a, are acute angles. In the second wiring 300a, the angle formed by the back surface 303a and the other side surface 306a is smaller than the angle formed by the back surface 303a and one of the side surfaces 305a. That is, in the cross-section perpendicular to the direction of extension of the second wiring 300a, the second wiring 300a is asymmetrical with its extension direction (D3 direction) as the center. By arranging the angle between the back surface 303a and the other side surface 306a in the second wiring 300a to be smaller than the angle between the back surface 303a and one of the side surfaces 305a, the line width of the back surface 303a can be increased, while suppressing the visibility of one of the side surfaces 305a of the second wiring 300a when viewed in a planar manner in the D1 direction, and improving the adhesion between the substrate 100a and the second wiring 300a. Furthermore, by increasing the cross-sectional area of ​​the second wiring 300a that intersects perpendicularly with the direction of wiring extension, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10a can be improved.

[0074] As described above, in this modified example, the wiring substrate 10a, by configuring the line widths of the back side 303a and front side 304a of the second wiring 300a on the substrate 100a to be smaller than the line widths of the back side 201a and front side 202a of the first wiring 200a, maintains the reliability of the first wiring 200a with radio wave transmission and reception functions while suppressing the visibility of the second wiring 300a when viewed in a planar orientation in the D1 direction. By configuring the line width of the surface of the first wiring 200a and the second wiring 300a that is in contact with the substrate 100a to be larger than the surface facing the opposite side of the surface in contact with the substrate 100a, the visibility of the first wiring 200a and the second wiring 300a when viewed in a planar orientation in the D1 direction is suppressed, and the adhesion between the substrate 100a and the first wiring 200a and the second wiring 300a is improved. By arranging the angle between the back surface 303a and the other side surface 306a in the second wiring 300a to be smaller than the angle between the back surface 303a and one of the side surfaces 305a, the visibility of one of the side surfaces 305a of the second wiring 300a when viewed in a planar manner in the D1 direction can be suppressed, and the adhesion between the substrate 100a and the second wiring 300a can be improved. Furthermore, by increasing the cross-sectional area of ​​the first wiring 200a and the second wiring 300a that intersects perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10a can be improved.

[0075] The wiring board 10a of this modification can be connected to a wireless communication circuit and mounted on a display device as a wireless communication module. By arranging the upper surface of the display area so that the board 100a faces the display area of ​​the display device, the visibility of the first wiring 200a and the second wiring 300a when viewed in a planar orientation in the D1 direction can be suppressed. By arranging the wiring board 10a such that the direction of the first wiring 200a is the longitudinal direction of the display area, and one side 305a of the second wiring 300a is in the upward direction (light incident direction) of the display area, light reflection caused by the other side 306a of the second wiring 300a can be suppressed. Therefore, a display device with a wiring board that has improved transparency, reliability, and conductivity and has radio wave transmission and reception functions can be provided.

[0076] <Second Variation> In the configurations shown in Figures 1 and 2, in the cross-section perpendicular to the direction of extension of the second wiring 300, the second wiring 300 is symmetrical in its long side direction (D3 direction). On the other hand, in this modified example, in the cross-section perpendicular to the direction of extension of the second wiring 300b, the second wiring 300b is asymmetrical with its long side direction (D3 direction) as the center.

[0077] The configuration of the wiring substrate 10b in this modified example will be explained using FIG4. Here, the configuration of the wiring substrate 10b in this modified example is the same as that of the wiring substrate 10 shown in FIGS. 1 and 2, except for the cross-sectional shape of the second wiring 300. Therefore, detailed descriptions of the parts identical to those shown in FIGS. 1 and 2 will be omitted.

[0078] [Structure of the wiring board] Figure 4 is a cross-sectional view showing one example of the wiring substrate of this modified example. Similar to the configuration shown in Figure 1, the wiring substrate 10b of this modified example includes a substrate 100b, a first wiring 200b, and a second wiring 300b. Figure 4(A) is an enlarged cross-sectional view along link A-A' in Figure 1. Figure 4(B) is an enlarged cross-sectional view along link B-B' in Figure 1.

[0079] As shown in Figure 4(A), the first wiring 200b has a back surface (first surface) 201b that is in contact with the substrate 100b, and a front surface (second surface) 202b facing the opposite side of the back surface 201b. As shown in Figure 4(B), the second wiring 300b has a back surface (third surface) 303b that is in contact with the substrate 100b, and a front surface (fourth surface) 304b facing the opposite side of the back surface 303b. As shown in Figures 4(A) and 4(B), the line width of the front surface 304b of the second wiring 300b is smaller than the line width of the front surface 202b of the first wiring 200b. Furthermore, the line width of the back surface 303b of the second wiring 300b is smaller than the line width of the back surface 201b of the first wiring 200b. By configuring the line widths of the front side 304b and back side 303b of the second wiring 300b to be smaller than the line widths of the front side 202b and back side 201b of the first wiring 200b, the reliability of the first wiring 200b, which has radio wave transmission and reception functions, can be maintained, while suppressing the visibility of the second wiring 300b, which is prepared for breaks in the first wiring 200b. Therefore, the conductivity and transparency of the wiring substrate 10b can be improved.

[0080] As shown in Figure 4(A), the line width of the back surface 201b of the first wiring 200b is larger than the line width of the front surface 202b of the first wiring 200b. As shown in Figure 4(B), the line width of the back surface 303b of the second wiring 300b is larger than the line width of the front surface 304b of the second wiring 300b. By configuring the line width of the surface in contact with the substrate 100b in the first wiring 200b and the second wiring 300b to be larger than the line width of the surface facing the opposite side of the surface in contact with the substrate 100b, the visibility of the first wiring 200b and the second wiring 300b when viewed in a planar manner in the D1 direction can be suppressed, and the adhesion between the substrate 100b and the first wiring 200b and the second wiring 300b can be improved. Furthermore, by increasing the area of ​​the cross-sections of the first wiring 200b and the second wiring 300b that intersect perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10b can be improved.

[0081] As shown in Figure 4(A), the first wiring 200b has a pair of side surfaces (9th and 10th surfaces) 209b and 210b, which extend along the direction of the first wiring 200b and are adjacent to the back surface 201b. In the first wiring 200b, the angles formed by the back surface 201b and one of the side surfaces 209b, and the angles formed by the back surface 201b and the other side surface 210b, are acute angles. In the first wiring 200b, the angles formed by the back surface 201b and one of the side surfaces 209b, and the angles formed by the back surface 201b and the other side surface 210b, are the same. That is, in a cross-section perpendicular to the direction of extension of the first wiring 200b, the first wiring 200b is linearly symmetrical about its extension direction (D2 direction).

[0082] As shown in Figure 4(B), the second wiring 300b has a pair of side surfaces (5th and 6th surfaces) 305b and 306b, which extend in the direction of the second wiring 300b and are adjacent to the back surface 303b. In the second wiring 300b, the angles formed by the back surface 303b and one of the side surfaces 305b, and the angles formed by the back surface 303b and the other side surface 306b, are acute angles. In the second wiring 300b, the angle formed by the back surface 303b and the other side surface 306b is smaller than the angle formed by the back surface 303b and one of the side surfaces 305b. In this modified example, one of the side surfaces 305b of the second wiring 300b is concave inward (negative side in the D2 direction). One of the side surfaces 305b includes an upper side surface (7th surface) 307b adjacent to the front surface 304b. In Figure 4(B), the angle between the front side 304b and the upper side 307b is approximately 90°. However, this is not a limitation; the angle between the front side 304b and the upper side 307b can be smaller than the exterior angle of the angle between the back side 303b and one of the side sides 305b (the angle between 180° and the back side 303b and one of the side sides 305b). The angle between the front side 304b and the upper side 307b should preferably be in the range of 60° or more and 90° or less. That is, in the second wiring 300b, one of the side sides 305b includes a shape (upper side 307b) that connects to the front side 304b at an angle smaller than the exterior angle of the angle between the back side 303b and one of the side sides 305b. However, this is not a limitation. Different surfaces may be included on one side 305b, and the surfaces of one side 305b may form corners (intersections), or they may be continuously connected by curved surfaces. In a cross-section perpendicular to the extension direction of the second wiring 300b, the second wiring 300b is asymmetrical with its extension direction (D3 direction) as the center. By arranging the angle between the back surface 303b and the other side 306b in the second wiring 300b to be smaller than the angle between the back surface 303b and one side 305b, the line width of the back surface 303b can be increased, the visibility of one side 305b of the second wiring 300b when viewed in a planar manner in the D1 direction can be suppressed, and the adhesion between the substrate 100b and the second wiring 300b can be improved. By making the angle between the front side 304b and the upper side 307b in the second wiring 300b smaller than the exterior angle between the back side 303b and one of its side sides 305b, the visibility of the upper side 307b of the second wiring 300b when viewed in a planar orientation in the D1 direction can be suppressed. Furthermore, by increasing the cross-sectional area of ​​the second wiring 300b that intersects perpendicularly with the direction of wiring extension, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10b can be improved.

[0083] As described above, in this modified example, the wiring substrate 10b is modified by making the line widths of the back side 303b and front side 304b of the second wiring 300b on the substrate 100b smaller than the line widths of the back side 201b and front side 202b of the first wiring 200b. This maintains the reliability of the first wiring 200b, which has radio wave transmission and reception functions, and suppresses the visibility of the second wiring 300b when viewed in a planar orientation in the D1 direction. By making the line width of the surface of the first wiring 200b and the second wiring 300b that is in contact with the substrate 100b larger than the surface facing the opposite side of the surface that is in contact with the substrate 100b, the visibility of the first wiring 200b and the second wiring 300b when viewed in a planar orientation in the D1 direction can be suppressed, and the adhesion between the substrate 100b and the first wiring 200b and the second wiring 300b can be improved. By configuring the angle between the back surface 303b and the other side surface 306b in the second wiring 300b to be smaller than the angle between the back surface 303b and one of the side surfaces 305b, the visibility of one of the side surfaces 305b of the second wiring 300b when viewed in a planar manner in the D1 direction can be suppressed, and the adhesion between the substrate 100b and the second wiring 300b can be improved. By configuring the angle between the front surface 304b and the upper side surface 307b in the second wiring 300b to be smaller than the outer angle of the angle between the back surface 303b and one of the side surfaces 305b, the visibility of the upper side surface 307b of the second wiring 300b when viewed in a planar manner in the D1 direction can be suppressed. Furthermore, by increasing the cross-sectional area of ​​the first wiring 200b and the second wiring 300b that intersects perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring board 10b can be improved.

[0084] The wiring board 10b of this modification can be connected to a wireless communication circuit and mounted as a wireless communication module in a display device. By arranging the upper surface of the display area so that the board 100b faces the display area of ​​the display device, the visibility of the first wiring 200b and the second wiring 300b when viewed in a planar orientation in the D1 direction can be suppressed. By arranging the wiring board 10b such that the direction of the first wiring 200b is the longitudinal direction of the display area, and the upper side surface 307b of the second wiring 300b is in the upward direction (light incident direction) of the display area, light reflection caused by the other side surface 306b of the second wiring 300b can be suppressed. Therefore, a display device with a wiring board having improved transparency, reliability, and conductivity, and possessing radio wave transmission and reception functions, can be provided.

[0085] <3rd Variation> In the configurations shown in Figures 1 and 2, in the cross-section perpendicular to the direction of extension of the second wiring 300, the second wiring 300 is symmetrical in its long side direction (D3 direction). On the other hand, in this modified example, in the cross-section perpendicular to the direction of extension of the second wiring 300c, the second wiring 300c is asymmetrical with its long side direction (D3 direction) as the center.

[0086] FIG5 will be used to illustrate the configuration of the wiring substrate 10c of this modified example. Here, the configuration of the wiring substrate 10c of this modified example is the same as that of the wiring substrate 10 shown in FIG1 and FIG2, except for the cross-sectional shape of the first wiring 200 and the second wiring 300. Therefore, detailed descriptions of the parts that are the same as those shown in FIG1 and FIG2 will be omitted.

[0087] [Structure of the wiring board] Figure 5 is a cross-sectional view showing one example of the wiring substrate of this modified example. Similar to the configuration shown in Figure 1, the wiring substrate 10c of this modified example includes a substrate 100c, a first wiring 200c, and a second wiring 300c. Figure 5(A) is an enlarged cross-sectional view along link A-A' in Figure 1. Figure 5(B) is an enlarged cross-sectional view along link B-B' in Figure 1.

[0088] As shown in Figure 5(A), the first wiring 200c has a back surface (first surface) 201c that is in contact with the substrate 100c, and a front surface (second surface) 202c facing the opposite side of the back surface 201c. As shown in Figure 5(B), the second wiring 300c has a back surface (third surface) 303c that is in contact with the substrate 100c, and a front surface (fourth surface) 304c facing the opposite side of the back surface 303c. As shown in Figures 5(A) and 5(B), the line width of the front surface 304c of the second wiring 300c is smaller than the line width of the front surface 202c of the first wiring 200c. Furthermore, the line width of the back surface 303c of the second wiring 300c is smaller than the line width of the back surface 201c of the first wiring 200c. By configuring the line widths of the front side 304c and back side 303c of the second wiring 300c to be smaller than the line widths of the front side 202c and back side 201c of the first wiring 200c, the reliability of the first wiring 200c, which has radio wave transmission and reception functions, can be maintained, while suppressing the visibility of the second wiring 300c, which is prepared for breaks in the first wiring 200c. Therefore, the conductivity and transparency of the wiring substrate 10c can be improved.

[0089] As shown in Figure 5(A), the line width of the back side 201c of the first wiring 200c is larger than the line width of the front side 202c of the first wiring 200c. As shown in Figure 5(B), the line width of the back side 303c of the second wiring 300c is larger than the line width of the front side 304c of the second wiring 300c. By configuring the line width of the surface in contact with the substrate 100c in the first wiring 200c and the second wiring 300c to be larger than the line width of the surface facing the opposite side of the surface in contact with the substrate 100c, the visibility of the first wiring 200c and the second wiring 300c when viewed in a planar manner in the D1 direction can be suppressed, and the adhesion between the substrate 100c and the first wiring 200c and the second wiring 300c can be improved. Furthermore, by increasing the area of ​​the cross-sections of the first wiring 200c and the second wiring 300c that intersect perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10c can be improved.

[0090] As shown in Figure 5(A), the first wiring 200c has a pair of side surfaces (9th and 10th surfaces) 209c and 210c, which extend in the direction of the first wiring 200c and are adjacent to the back surface 201c. In the first wiring 200c, the angles formed by the back surface 201c and one of the side surfaces 209c, and the angles formed by the back surface 201c and the other side surface 210c, are acute angles. In the first wiring 200c, the angles formed by the back surface 201c and one of the side surfaces 209c, and the angles formed by the back surface 201c and the other side surface 210c, are the same. In this modified example, one of the side surfaces 209c of the first wiring 200c is recessed inward (positive side in the D3 direction). One of the side surfaces 209c includes an upper side surface (11th surface) 211c adjacent to the front surface 202c. The other side 210c of the first wiring 200c is recessed inward (negative side in the D3 direction). The other side 210c includes the upper side (12th side) 212c adjacent to the front side 202c. In Figure 5(A), the angles formed by the front side 202c and the upper side 211c, and the angles formed by the front side 202c and the upper side 212c, are approximately 90°. However, this is not a limitation; the angle between the front side 202c and the upper side 211c may be smaller than the exterior angle of the angle between the back side 201c and one of the side sides 209c. The angle between the front side 202c and the upper side 211c should preferably be in the range of 60° to 90°. The angle between the front side 202c and the upper side 212c may be smaller than the exterior angle of the angle between the back side 201c and the other side side 210c. The angle between the front side 202c and the upper side 212c should preferably be between 60° and 90°. That is, in the first wiring 200c, one side 209c includes a shape (upper side 211c) that connects to the front side 202c at an angle smaller than the exterior angle of the angle formed by the back side 201c and the upper side 209c. In the first wiring 200c, the other side 210c includes a shape (upper side 212c) that connects to the front side 202c at an angle smaller than the exterior angle of the angle formed by the back side 201c and the other side 210c. However, this is not a limitation; one side 209c and the other side 210c may further include different surfaces, and the surfaces of one side 209c and the other side 210c may form corners (intersections), or they may be continuously connected by curved surfaces. That is, in the cross section that intersects perpendicularly with the direction of extension of the first wiring 200c, the first wiring 200c is linearly symmetrical with its extension direction (D2 direction) as the center.By ensuring that the angle between the front side 202c and the upper side 211c in the first wiring 200c is smaller than the exterior angle between the back side 201c and one of the side sides 209c, and that the angle between the front side 202c and the upper side 212c is smaller than the exterior angle between the back side 201c and the other side 210c, the visibility of the upper side 211c and the upper side 212c of the first wiring 200c when viewed in a planar manner in the D1 direction can be suppressed. Furthermore, by increasing the cross-sectional area of ​​the first wiring 200c that intersects perpendicularly with the direction of wiring extension, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10c can be improved.

[0091] As shown in Figure 5(B), the second wiring 300c has a pair of side surfaces (5th and 6th surfaces) 305c and 306c, which extend in the direction of the second wiring 300c and are adjacent to the back surface 303c. In the second wiring 300c, the angles formed by the back surface 303c and one of the side surfaces 305c, and the angles formed by the back surface 303c and the other side surface 306c, are acute angles. In the second wiring 300c, the angle formed by the back surface 303c and the other side surface 306c is smaller than the angle formed by the back surface 303c and one of the side surfaces 305c. In this modified example, one of the side surfaces 305c of the second wiring 300c is recessed inward (negative side in the D2 direction). One of the side surfaces 305c includes an upper side surface (7th surface) 307c adjacent to the front surface 304c. The other side 306c of the second wiring 300c is recessed inward (towards the front side in the D2 direction). The other side 306c includes the upper side (eighth side) 308c adjacent to the front side 304c. In Figure 5(B), the angles formed by the front side 304c and the upper side 307c, and the angles formed by the front side 304c and the upper side 308c, are approximately 90°. However, this is not a limitation; the angle between the front side 304c and the upper side 307c may be smaller than the exterior angle of the angle between the back side 303c and one of the side sides 305c. The angle between the front side 304c and the upper side 307c should preferably be between 60° and 90°. The angle between the front side 304c and the upper side 308c may be smaller than the exterior angle of the angle between the back side 303c and the other side side 306c. The angle between the front side 304c and the upper side 308c should preferably be between 60° and 90°. That is, in the second wiring 300c, one side 305c includes a shape (upper side 307c) that connects to the front side 304c at an angle smaller than the exterior angle of the angle formed between the back side 303c and the upper side 305c. In the second wiring 300c, the other side 306c includes a shape (upper side 308c) that connects to the front side 304c at an angle smaller than the exterior angle of the angle formed between the back side 303c and the upper side 306c. However, this is not a limitation; one side 305c and the other side 306c may further include different surfaces, and the surfaces of one side 305c and the other side 306c may form corners (intersections), or they may be continuously connected by curved surfaces. In the cross section that intersects perpendicularly with the direction of extension of the second wiring 300c, the second wiring 300c is asymmetrical with its extension direction (D3 direction) as the center.By configuring the angle between the back surface 303c and the other side surface 306c in the second wiring 300c to be smaller than the angle between the back surface 303c and one of the side surfaces 305c, the line width of the back surface 303c can be increased, the visibility of one of the side surfaces 305c of the second wiring 300c can be suppressed when viewed in a planar manner in the D1 direction, and the adhesion between the substrate 100c and the second wiring 300c can be improved. By making the angle between the front side 304c and the upper side 307c smaller than the exterior angle between the back side 303c and one of the side sides 305c in the second wiring 300c, and by making the angle between the front side 304c and the upper side 308c smaller than the exterior angle between the back side 303c and the other side 306c, the visibility of the upper side 307c and the upper side 308c of the second wiring 300c when viewed in a planar manner in the D1 direction can be suppressed. Furthermore, by increasing the cross-sectional area of ​​the second wiring 300c that intersects perpendicularly with the direction of wiring extension, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10c can be improved.

[0092] As described above, in this modified example, the wiring substrate 10c, by configuring the line width of the front side 304c of the second wiring 300c on the substrate 100c to be smaller than the line width of the front side 202c of the first wiring 200c, maintains the reliability of the first wiring 200c with radio wave transmission and reception functions while suppressing the visibility of the second wiring 300c when viewed in a planar orientation in the D1 direction. By configuring the line width of the surface of the first wiring 200c and the second wiring 300c that is in contact with the substrate 100c to be larger than the surface facing the opposite side of the surface in contact with the substrate 100c, the visibility of the first wiring 200c and the second wiring 300c when viewed in a planar orientation in the D1 direction is suppressed, and the adhesion between the substrate 100c and the first wiring 200c and the second wiring 300c is improved. By making the angle between the front side 202c and the upper side 211c smaller than the exterior angle between the back side 201c and one of the side sides 209c in the first wiring 200c, and by making the angle between the front side 202c and the upper side 212c smaller than the exterior angle between the back side 201c and the other side 210c in the same direction, the visibility of the upper side 211c and the upper side 212c of the first wiring 200c when viewed in a planar orientation in the D1 direction can be suppressed. By making the angle between the back side 303c and the other side 306c smaller than the angle between the back side 303c and one of the side sides 305c in the second wiring 300c, the visibility of one of the side sides 305c of the second wiring 300c when viewed in a planar orientation in the D1 direction can be suppressed, and the adhesion between the substrate 100c and the second wiring 300c can be improved. By making the angle between the front side 304c and the upper side 307c smaller than the exterior angle between the back side 303c and one of the side sides 305c in the second wiring 300c, and by making the angle between the front side 304c and the upper side 308c smaller than the exterior angle between the back side 303c and the other side 306c in the same direction, the visibility of the upper side 307c and the upper side 308c of the second wiring 300c when viewed in a planar orientation in the D1 direction can be suppressed. Furthermore, by increasing the cross-sectional area of ​​the first wiring 200c and the second wiring 300c that intersects perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10c can be improved.

[0093] Furthermore, according to this modified example, since the sides 209c and 210c of the first wiring 200c are recessed inwards, and the sides 305c and 306c of the second wiring 300c are also recessed inwards, the maximum width of the first wiring 200c and the second wiring 300c when viewed from an oblique angle can be suppressed. This makes the first wiring 200c and the second wiring 300c difficult to see, for example, from the front of a display, and makes it difficult for the user to identify them with the naked eye. Also, generally speaking, when alternating current flows in a wiring, the higher the frequency, the more difficult it becomes for current to flow in the center of the wiring, resulting in current flowing on the surface of the wiring (skin effect). In this modified example, by making the sides of the first wiring 200c and the second wiring 300c concave, current can flow over a larger area of ​​the cross-section of the first wiring 200c and the second wiring 300c. Therefore, the cross-section of the first wiring 200c and the second wiring 300c can be utilized efficiently. Furthermore, because the sides of the first wiring 200c and the second wiring 300c are concave, light incident obliquely relative to the D1 direction is less likely to be reflected in the D1 direction, making it difficult to distinguish the first wiring 200c and the second wiring 300c with the naked eye.

[0094] The wiring board 10c of this modification can be connected to a wireless communication circuit and mounted on a display device as a wireless communication module. By arranging the upper surface of the display area so that the board 100c faces the display area of ​​the display device, the visibility of the first wiring 200c and the second wiring 300c when viewed in a planar orientation in the D1 direction can be suppressed. By arranging the wiring board 10c such that the direction of the first wiring 200 is the longitudinal direction of the display area, and the upper side surface 307c of the second wiring 300c is in the upward direction (light incident direction) of the display area, light reflection caused by the other side surface 306c of the second wiring 300c can be suppressed. Therefore, a display device with a wiring board having improved transparency, reliability, and conductivity, and possessing radio wave transmission and reception functions, can be provided.

[0095] <4th Variation> In the configurations shown in Figures 1 and 2, in the cross-section perpendicular to the direction of extension of the second wiring 300, the second wiring 300 is symmetrical in its long side direction (D3 direction). On the other hand, in this modified example, in the cross-section perpendicular to the direction of extension of the second wiring 300d, the second wiring 300d is asymmetrical with its long side direction (D3 direction) as the center.

[0096] FIG6 will be used to illustrate the configuration of the wiring substrate 10d in this modified example. Here, the configuration of the wiring substrate 10d in the modified example is the same as that of the wiring substrate 10 shown in FIG1 and FIG2, except for the cross-sectional shapes of the first wiring 200 and the second wiring 300. Therefore, detailed descriptions of the parts that are the same as those shown in FIG1 and FIG2 will be omitted.

[0097] [Structure of the wiring board] Figure 6 is a cross-sectional view showing one example of the wiring substrate of this modified example. Similar to the configuration shown in Figure 1, the wiring substrate 10d of this modified example includes a substrate 100d, a first wiring 200d, and a second wiring 300d. Figure 6(A) is an enlarged cross-sectional view along link A-A' in Figure 1. Figure 6(B) is an enlarged cross-sectional view along link B-B' in Figure 1.

[0098] As shown in Figure 6(A), the first wiring 200d has a back side (first surface) 201d that is in contact with the substrate 100d, and a front side (second surface) 202d facing the opposite side of the back side 201d. As shown in Figure 6(B), the second wiring 300d has a back side (third surface) 303d that is in contact with the substrate 100d, and a front side (fourth surface) 304d facing the opposite side of the back side 303d. As shown in Figures 6(A) and 6(B), the line width of the front side 304d of the second wiring 300d is smaller than the line width of the front side 202d of the first wiring 200d. Furthermore, the line width of the back side 303d of the second wiring 300d is smaller than the line width of the back side 201d of the first wiring 200d. By configuring the line widths of the front side 304d and back side 303d of the second wiring 300d to be smaller than the line widths of the front side 202d and back side 201d of the first wiring 200d, the reliability of the first wiring 200d, which has radio wave transmission and reception functions, can be maintained, while suppressing the visibility of the second wiring 300d, which is prepared for breaks in the first wiring 200d. Therefore, the conductivity and transparency of the wiring substrate 10d can be improved.

[0099] As shown in Figure 6(A), the line width of the back side 201d of the first wiring 200d is larger than the line width of the front side 202d of the first wiring 200d. As shown in Figure 6(B), the line width of the back side 303d of the second wiring 300d is larger than the line width of the front side 304d of the second wiring 300d. By configuring the line width of the surface of the first wiring 200d and the second wiring 300d that is in contact with the substrate 100d to be larger than the line width of the surface facing the opposite side of the surface that is in contact with the substrate 100d, the visibility of the first wiring 200d and the second wiring 300d when viewed in a planar manner in the D1 direction can be suppressed, and the adhesion between the substrate 100d and the first wiring 200d and the second wiring 300d can be improved. Furthermore, by increasing the area of ​​the cross-sections of the first wiring 200d and the second wiring 300d that intersect perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10d can be improved.

[0100] As shown in Figure 6(A), the first wiring 200d has a pair of side surfaces (9th and 10th surfaces) 209d and 210d, which extend in the direction of the first wiring 200d and are adjacent to the back surface 201d. In the first wiring 200d, the angles formed by the back surface 201d and one of the side surfaces 209d, and the angles formed by the back surface 201d and the other side surface 210d, are acute angles. In the first wiring 200d, the angles formed by the back surface 201d and one of the side surfaces 209d, and the angles formed by the back surface 201d and the other side surface 210d, are the same. In this modified example, one of the side surfaces 209d of the first wiring 200d is recessed inward (positive side in the D3 direction). One of the side surfaces 209d includes an upper side surface (11th surface) 211d adjacent to the front surface 202d. The other side 210d of the first wiring 200d is recessed inward (negative side in the D3 direction). The other side 210d includes the upper side 212d (the 12th side) adjacent to the front side 202d. In Figure 6(A), the angles formed by the front side 202d and the upper side 211d, and the angles formed by the front side 202d and the upper side 212d, are approximately 90°. However, this is not a limitation; the angle between the front side 202d and the upper side 211d may be smaller than the exterior angle of the angle between the back side 201d and one of the side sides 209d. The angle between the front side 202d and the upper side 211d should preferably be in the range of 60° to 90°. The angle between the front side 202d and the upper side 212d may be smaller than the exterior angle of the angle between the back side 201d and the other side 210d. The angle between the front side 202d and the upper side 212d should preferably be between 60° and 90°. That is, in the first wiring 200d, one side 209d includes a shape (upper side 211d) that connects to the front side 202d at an angle smaller than the exterior angle of the angle formed by the back side 201d and the upper side 209d. In the first wiring 200d, the other side 210d includes a shape (upper side 212d) that connects to the front side 202d at an angle smaller than the exterior angle of the angle formed by the back side 201d and the other side 210d. However, this is not a limitation; one side 209d and the other side 210d may further include different surfaces, and the surfaces constituting one side 209d and the other side 210d may form corners (intersections), or they may be continuously connected by curved surfaces. The first wiring 200d in this modified example further has a protrusion d, which extends in a direction orthogonal to the direction of the first wiring 200d and protrudes towards the front surface between the front surface 202d and the adjacent surface.That is, the first wiring 200d has a protrusion d protruding in the D3 direction between the front side 202d and the upper side 211d, and between the front side 202d and the upper side 212d. In other words, in a cross section perpendicular to the extension direction of the first wiring 200d, the first wiring 200d is linearly symmetrical about its extension direction (D2 direction). Because the angle between the front side 202d and the upper side 211d in the first wiring 200d is smaller than the exterior angle between the back side 201d and one of the side surfaces 209d, and the angle between the front side 202d and the upper side 212d is smaller than the exterior angle between the back side 201d and the other side surface 210d, the visibility of the upper side surfaces 211d and 212d of the first wiring 200d when viewed in a planar manner in the D1 direction can be suppressed. Furthermore, by increasing the cross-sectional area of ​​the first wiring 200d, which intersects perpendicularly with the direction of wiring extension, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10d can be improved.

[0101] As shown in Figure 6(B), the second wiring 300d has a pair of side surfaces (5th and 6th surfaces) 305d and 306d, which extend in the direction of the second wiring 300d and are adjacent to the back surface 303d. In the second wiring 300d, the angles formed by the back surface 303d and one of the side surfaces 305d, and the angles formed by the back surface 303d and the other side surface 306d, are acute angles. In the second wiring 300d, the angle formed by the back surface 303d and the other side surface 306d is smaller than the angle formed by the back surface 303d and one of the side surfaces 305d. In this modified example, one of the side surfaces 305d of the second wiring 300d is concave inward (negative side in the D2 direction). One of the side surfaces 305d includes an upper side surface (7th surface) 307d adjacent to the front surface 304d. The other side 306d of the second wiring 300d is recessed inward (towards the front side in the D2 direction). The other side 306d includes the upper side 308d (the 8th side) adjacent to the front side 304d. In Figure 6(B), the angles formed by the front side 304d and the upper side 307d, and the angles formed by the front side 304d and the upper side 308d, are approximately 90°. However, this is not a limitation; the angle between the front side 304d and the upper side 307d may be smaller than the exterior angle of the angle between the back side 303d and one of the side sides 305d. The angle between the front side 304d and the upper side 307d should preferably be between 60° and 90°. The angle between the front side 304d and the upper side 308d may be smaller than the exterior angle of the angle between the back side 303d and the other side 306d. The angle between the front side 304d and the upper side 308d should preferably be between 60° and 90°. That is, in the second wiring 300d, one side 305d includes a shape (upper side 307d) that connects to the front side 304d at an angle smaller than the exterior angle of the angle formed by the back side 303d and the other side 305d. In the second wiring 300d, the other side 306d includes a shape (upper side 308d) that connects to the front side 304d at an angle smaller than the exterior angle of the angle formed by the back side 303d and the other side 306d. However, this is not a limitation; one side 305d and the other side 306d may further include different surfaces, and the surfaces constituting one side 305d and the other side 306d may form corners (intersections), or they may be continuously connected by curved surfaces. The second wiring 300d in this modified example further has a protrusion d, which extends in a direction orthogonal to the direction of the second wiring 300d and protrudes towards the front surface between the front surface 304d and the adjacent surface.That is, the second wiring 300d has a protrusion d protruding in the D2 direction between the front side 304d and the upper side 307d, and between the front side 202d and the upper side 308d. In a cross section perpendicular to the extension direction of the second wiring 300d, the second wiring 300d is asymmetrical with its extension direction (D3 direction) as the center. By arranging the angle between the back side 303d and the other side 306d in the second wiring 300d to be smaller than the angle between the back side 303d and one of the side sides 305d, the line width of the back side 303d can be increased, the visibility of one of the side sides 305d of the second wiring 300d can be suppressed when viewed in a planar manner in the D1 direction, and the adhesion between the substrate 100d and the second wiring 300d can be improved. By making the angle between the front side 304d and the upper side 307d smaller than the exterior angle between the back side 303d and one of the side sides 305d in the second wiring 300d, and by making the angle between the front side 304d and the upper side 308d smaller than the exterior angle between the back side 303d and the other side 306d, the visibility of the upper side 307d and the upper side 308d of the second wiring 300d when viewed in a planar manner in the D1 direction can be suppressed. Furthermore, by increasing the cross-sectional area of ​​the second wiring 300d that intersects perpendicularly with the direction of wiring extension, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10d can be improved.

[0102] As described above, in this modified example, the wiring substrate 10d, by configuring the line width of the front side 304d of the second wiring 300d on the substrate 100d to be smaller than the line width of the front side 202d of the first wiring 200d, maintains the reliability of the first wiring 200d, which has radio wave transmission and reception functions, and suppresses the visibility of the second wiring 300d when viewed in a planar orientation in the D1 direction. By configuring the line width of the surface of the first wiring 200d and the second wiring 300d that is in contact with the substrate 100d to be larger than the surface facing the opposite side of the surface in contact with the substrate 100d, the visibility of the first wiring 200d and the second wiring 300d when viewed in a planar orientation in the D1 direction can be suppressed, and the adhesion between the substrate 100d and the first wiring 200d and the second wiring 300d can be improved. By making the angle between the front side 202d and the upper side 211d smaller than the exterior angle between the back side 201d and one of the side sides 209d in the first wiring 200d, and by making the angle between the front side 202d and the upper side 212d smaller than the exterior angle between the back side 201d and the other side 210d in the same direction, the visibility of the upper side 211d and the upper side 212d of the first wiring 200d when viewed in a planar orientation in the D1 direction can be suppressed. By making the angle between the back side 303d and the other side 306d smaller than the angle between the back side 303d and one of the side sides 305d in the second wiring 300d, the visibility of one of the side sides 305d of the second wiring 300d when viewed in a planar orientation in the D1 direction can be suppressed, and the adhesion between the substrate 100d and the second wiring 300d can be improved. By making the angle between the front side 304d and the upper side 307d smaller than the exterior angle between the back side 303d and one of the side sides 305d in the second wiring 300d, and by making the angle between the front side 304d and the upper side 308d smaller than the exterior angle between the back side 303d and the other side 306d in the same direction, the visibility of the upper side 307d and the upper side 308d of the second wiring 300d when viewed in a planar orientation in the D1 direction can be suppressed. Furthermore, by increasing the cross-sectional area of ​​the first wiring 200d and the second wiring 300d that intersects perpendicularly with their respective wiring extension directions, wiring resistance can be suppressed. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10d can be improved.

[0103] The wiring board 10d of this modification can be connected to a wireless communication circuit and mounted on a display device as a wireless communication module. By arranging the wiring board 10d on the upper surface of the display area so that the board 100d faces the display area of ​​the display device, the visibility of the first wiring 200d and the second wiring 300d can be suppressed when viewed in a planar orientation in the D1 direction. By arranging the wiring board 10d such that the direction of the first wiring 200d is the longitudinal direction of the display area, and the upper side surface 307d of the second wiring 300d is in the upward direction (light incident direction) of the display area, light reflection caused by the other side surface 306d of the second wiring 300d can be suppressed. When the wiring board 10d is disposed on the upper surface of the display area, a protective film can be disposed to cover the upper surface of the board 100d. By having protrusions d on the first wiring 200d and the second wiring 300d, the adhesion between the first wiring 200d and the second wiring 300d and the protective film can be improved. Therefore, a display device with a wiring substrate that has improved transparency, reliability, and conductivity and has radio wave transmission and reception functions can be provided.

[0104] <5th Variation> The wiring substrate 10e of this modification has a substrate 100e, a first wiring 200e, and a second wiring 300e that are the same as those of the wiring substrate 10 shown in FIG1 and FIG2. The wiring substrate 10e of this modification includes a curved surface (bent portion) e at the intersection of the first wiring 200e and the second wiring 300e.

[0105] The configuration of the wiring substrate 10e in this modified example will be explained using Figures 7 and 8. Here, the configuration of the wiring substrate 10e in this modified example is the same as that of the wiring substrate 10 shown in Figures 1 and 2, except for the curved surface e at the intersection of the first wiring 200e and the second wiring 300e. Therefore, detailed descriptions of the parts identical to those shown in Figures 1 and 2 will be omitted.

[0106] [Structure of the wiring board] Figure 7 is a top view showing an example of the wiring board of this embodiment. Figure 7 is an enlarged top view of region C in Figure 1. Figure 8 is a cross-sectional view showing an example of the wiring board of this modified example. Figure 8(A) is an enlarged cross-sectional view of link line D-D' in Figure 7. Figure 8(B) is an enlarged cross-sectional view of link line E-E' in Figure 7.

[0107] As shown in Figure 7, the wiring substrate 10e includes a substrate 100e, a first wiring 200e, and a second wiring 300e. In this modified example, the first wiring 200e and the second wiring 300e are orthogonal. However, this is not a limitation; the planar shapes of the first wiring 200e and the second wiring 300e can be intersecting or connected. As shown in Figures 7 and 8, the upper surface of the substrate 100e, the side adjacent to the back surface (first surface) 201e of the first wiring 200e, and the side adjacent to the back surface (third surface) 303e of the second wiring 300e form four corners in a planar view. In this modified example, the corner formed by the upper surface of the substrate 100e, the side surface (10th surface) 210e of the first wiring 200e, and the side surface (6th surface) 306e of the second wiring 300e includes a continuous curved surface e connecting these surfaces. That is, the curved surface e continuously connects the side surface 210e of the first wiring 200e and the side surface 306e of the second wiring 300e. This curved surface e has an inwardly curved shape in either the cross-section perpendicular to the direction of the first wiring 200e or the cross-section perpendicular to the direction of the second wiring 300e. However, this is not a limitation. The curved surface e may be disposed at one or more of the four corners formed from the upper surface of the substrate 100e, the side adjacent to the back surface 201e of the first wiring 200e, and the side adjacent to the back surface 303e of the second wiring 300e, as viewed from a planar perspective. That is, in a cross-section containing the corner of the curved surface e that intersects perpendicularly with the direction of the first wiring 200e, the first wiring 200e is asymmetrical with its long side direction (D2 direction) as the center. In a cross-section containing the corner of the curved surface e that intersects perpendicularly with the direction of the second wiring 300e, the second wiring 300e is asymmetrical with its long side direction (D3 direction). In a cross-section perpendicular to the direction of the second wiring 300e, the radius of curvature of the curved surface e should preferably be 20% or more of the height of the second wiring 300e.

[0108] By having curved surfaces e in the corners formed by the upper surface of the substrate 100e, the side adjacent to the back surface 201e of the first wiring 200e, and the side adjacent to the back surface 303e of the second wiring 300e, the line widths of the back surfaces 201e and 303e can be increased, thus improving the adhesion between the substrate 100e and the first wiring 200e, and between the substrate 100e and the second wiring 300e. Furthermore, by increasing the cross-sectional area of ​​the first wiring 200e and the second wiring 300e that intersect perpendicularly with their respective wiring extension directions, the visibility of the front surface (second surface) 202e of the first wiring 200e and the front surface (fourth surface) 304e of the second wiring 300e when viewed in a planar manner in the D1 direction can be suppressed, and wiring resistance can be reduced. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10e can be improved.

[0109] The wiring board 10e of this modification can be connected to a wireless communication circuit and mounted on a display device as a wireless communication module. By arranging the upper surface of the display area so that the board 100e faces the display area of ​​the display device, the visibility of the first wiring 200e and the second wiring 300e when viewed in a planar orientation in the D1 direction can be suppressed. By arranging the wiring board 10e such that the direction of the first wiring 200e is the longitudinal direction of the display area and the curved surface e is the downward direction of the display area, light reflection caused by the curved surface e can be suppressed. Therefore, a display device with a wiring board that has improved transparency, reliability, and conductivity and has radio wave transmission and reception functions can be provided.

[0110] <Sixth Variation> The wiring substrate 10f of this modification has the same substrate 100f, first wiring 200f, and second wiring 300f as the wiring substrate 10a (FIG. 3) of the first modification. The wiring substrate 10f of this modification includes a curved surface f at the intersection of the first wiring 200f and the second wiring 300f.

[0111] The configuration of the wiring substrate 10f in this modified example will be explained using Figures 9 and 10. Here, the configuration of the wiring substrate 10f in this modified example is the same as that of the wiring substrate 10a in the first modified example shown in Figure 3, except for the curved surface f at the intersection of the first wiring 200f and the second wiring 300f. Therefore, detailed descriptions of the parts identical to those in the first modified example will be omitted.

[0112] [Structure of the wiring board] Figure 9 is a top view showing an example of a wiring board according to this embodiment. Figure 9 is an enlarged top view of region C in Figure 1. Figure 10 is a cross-sectional view showing an example of a wiring board according to this modified example. Figure 10(A) is an enlarged cross-sectional view along link D-D' in Figure 9. Figure 10(B) is an enlarged cross-sectional view along link E-E' in Figure 9.

[0113] As shown in Figure 9, the wiring substrate 10f includes a substrate 100f, a first wiring 200f, and a second wiring 300f. In this modified example, the first wiring 200f and the second wiring 300f are orthogonal. However, this is not a limitation; the planar shapes of the first wiring 200f and the second wiring 300f can be intersecting or connected. As shown in Figures 9 and 10, the upper surface of the substrate 100f, the side adjacent to the back surface (first surface) 201f of the first wiring 200f, and the side adjacent to the back surface (third surface) 303f of the second wiring 300f form four corners in a planar view. In this modified example, a continuous curved surface f is included in the corner formed by the upper surface of the substrate 100f, the side surface (9th surface) 209f of one side of the first wiring 200f, and the side surface (6th surface) 306f of the other side of the second wiring 300f. That is, the curved surface f continuously connects the side surface 209f of one side of the first wiring 200f and the side surface 306f of the other side of the second wiring 300f. Furthermore, a continuous curved surface f is included in the corner formed by the upper surface of the substrate 100f, the side surface (10th surface) 210f of the other side of the first wiring 200f, and the side surface 306f of the other side of the second wiring 300f. That is, the curved surface f continuously connects the side surface 210f of the other side of the first wiring 200f and the side surface 306f of the other side of the second wiring 300f. However, this is not a limitation. The curved surface f may be disposed at one or more of the four corners formed by the upper surface of the substrate 100f, the side adjacent to the back surface 201f of the first wiring 200f, and the side adjacent to the back surface 303f of the second wiring 300f, as viewed from a planar perspective. Preferably, the curved surface f is disposed at one or more of the two corners formed by the upper surface of the substrate 100f, the side adjacent to the back surface 201f of the first wiring 200f, and the side surface 306f on the other side of the second wiring 300f. That is, in the cross section containing the corner of the curved surface f that intersects perpendicularly with the direction of the first wiring 200f, the first wiring 200f is linearly symmetrical about its long side direction (D2 direction). In the section containing the corner of the curved surface f that intersects perpendicularly with the direction of the second wiring 300f, the second wiring 300f is asymmetrical with its long side direction (D3 direction) as the center. In the section perpendicular to the direction of the second wiring 300e, the radius of curvature of the curved surface f should preferably be more than 20% of the height of the second wiring 300e.

[0114] By having curved surfaces f in the corners formed by the upper surface of the substrate 100f, the side adjacent to the back surface 201f of the first wiring 200f, and the other side surface 306f of the second wiring 300f, the line widths of the back surfaces 201f and 303f can be increased, thus improving the adhesion between the substrate 100f and the first wiring 200f, and between the substrate 100f and the second wiring 300f. Furthermore, by increasing the cross-sectional area of ​​the first wiring 200f and the second wiring 300f that intersects perpendicularly with their respective wiring extension directions, the visibility of the front surface (second side) 202f of the first wiring 200f and the front surface (fourth side) 304f of the second wiring 300f when viewed in a planar manner in the D1 direction can be suppressed, and wiring resistance can be reduced. Therefore, the transparency, reliability, and conductivity of the wiring substrate 10f can be improved.

[0115] The wiring board 10f of this modification can be connected to a wireless communication circuit and mounted on a display device as a wireless communication module. By arranging the upper surface of the display area so that the board 100f faces the display area of ​​the display device, the visibility of the first wiring 200f and the second wiring 300f when viewed in a planar orientation in the D1 direction can be suppressed. By arranging the wiring board 10f such that the direction of the first wiring 200f is the longitudinal direction of the display area and the curved surface f is the downward direction of the display area, light reflection caused by the curved surface f can be suppressed. Therefore, a display device with a wiring board that has improved transparency, reliability, and conductivity and has radio wave transmission and reception functions can be provided.

[0116] [Manufacturing method of wiring board 10] The manufacturing method of the wiring board of this embodiment and its variations will be explained using Figures 11 and 12. In Figures 11 and 12, elements that are the same as those shown in the above embodiments and variations are marked with the same symbols. Here, detailed descriptions of the parts that are the same as those shown in Figures 1 to 10 will be omitted.

[0117] Figure 11(A) is a diagram showing the steps of forming a conductive layer 400 on the upper surface of a substrate 100 in the manufacturing method of the wiring substrate of this embodiment. As shown in Figure 11(A), the conductive layer 400 is formed on approximately the entire surface of the substrate 100. In this embodiment, the thickness of the conductive layer 400 is 200 nm. However, it is not limited to this, and the thickness of the conductive layer 400 can be appropriately selected in the range of 10 nm or more and 1000 nm or less. In this embodiment, the conductive layer 400 is formed using copper by sputtering. As a method for forming the conductive layer 400, plasma chemical vapor deposition (CVD) can also be used.

[0118] Figure 11(B) illustrates the step of forming an insulating layer 500 on the upper surface of a substrate 100 in the manufacturing method of the wiring board according to this embodiment. As shown in Figure 11(B), the insulating layer 500 is formed on approximately the entire surface of the substrate 100. The thickness of the insulating layer 500 is 1200 nm. However, it is not limited to this; the thickness of the insulating layer 500 can be appropriately selected in the range of 500 nm or more and 2500 nm or less. The insulating layer 500 can be made of any material with electrical insulating properties.

[0119] Figure 11(C) illustrates the steps in the manufacturing method of the wiring substrate according to this embodiment, specifically forming a first trench 510 for arranging the first wiring 200 and a second trench 520 (not shown) for arranging the second wiring 300 on the upper surface of the insulating layer 500. As shown in Figure 11(C), in this embodiment, the first trench 510 and the second trench 520 are formed by an imprinting method. The insulating layer 500 is softened, and a mold 600 having protrusions corresponding to the first trench 510 and the second trench 520 is pressed in. By hardening the insulating layer 500 in this state and peeling the mold 600 off the insulating layer 500, the insulating layer 500 with the cross-sectional structure shown in Figure 11(D) can be obtained.

[0120] The first groove 510 corresponds to the first wiring 200, and the second groove 520 corresponds to the second wiring 300. Therefore, the first groove 510 extending in the first direction and the second groove 520 extending in the second direction are orthogonal. Furthermore, the first groove 510 is formed to be longer than the second groove 520, and the opening width of the first groove 510 is formed to be larger than the opening width of the second groove 520. Here, the opening width refers to the width of the opening parallel to the upper surface of the substrate 100 in a cross-section perpendicular to the direction of extension of each groove. The depth-to-width ratio of the first groove 510 and the second groove 520 can be appropriately selected according to the application. Here, the depth-to-width ratio of the first groove 510 and the second groove 520 is defined as the depth relative to the opening width. If the aspect ratio of the first trench 510 and the second trench 520 is too small, it will be difficult to form the fine patterns of the first wiring 200 and the second wiring 300 in the wiring substrate 10. If the aspect ratio of the first trench 510 and the second trench 520 is too large, it will be difficult to fill the first trench 510 and the second trench 520 with conductors. Alternatively, the opening width of the first trench 510 can be set to be the same as the opening width of the second trench 520.

[0121] When forming the first groove 510 and the second groove 520 by imprinting, the direction in which the mold 600 is peeled from the insulating layer 500 is preferably the direction in which the longer first wiring 200 (first groove 510) extends. More preferably, the direction in which the mold 600 is peeled from the insulating layer 500 is from one side 305 of the second wiring 300 to the other side 306. That is, more preferably, the direction in which the mold 600 is peeled from the insulating layer 500 is from the first side 102 of the substrate 100 to the second side 104 (the direction of the first wiring 200, the first direction, and the opposite direction of D2). By forming the insulating layer 500 in this way, the cross-sectional shapes of the first wiring 200 and the second wiring 300 in the aforementioned embodiments and modifications can be formed. However, this is not a limitation; in the manufacturing methods of the wiring substrate 10 in the aforementioned embodiments and modifications, the insulating layer 500 can also be formed by photolithography. In this case, the resist pattern can be formed by photolithography to expose the conductive layer 400 in the area where the first wiring 200 and the second wiring 300 are to be formed.

[0122] As shown in Figure 11(D), there may be residual insulating material at the bottom of the first trench 510 and the second trench 520 formed by the insulating layer 500. Therefore, the residual insulating material can be removed by wet treatment using permanganate solution or N-methyl-2-pyrrolidone, or by dry treatment using oxygen plasma. By removing the residual insulating material, the first trench 510 and the second trench 520, exposing the conductive layer 400, can be formed as shown in Figure 12(A).

[0123] Figure 12(B) illustrates the steps in the manufacturing method of the wiring substrate according to this embodiment, including forming a first conductor 410 corresponding to the first wiring 200 and a second conductor 420 (not shown) corresponding to the second wiring 300. The first conductor 410 and the second conductor 420 are used to fill the first trench 510 and the second trench 520 of the insulating layer 500 formed in Figure 12(A). In this embodiment, the first trench 510 and the second trench 520 of the insulating layer 500 are filled with copper using an electrolytic plating method, with the conductive layer 400 serving as a seed layer. Furthermore, the first conductor 410 and the second conductor 420 are formed to protrude from the upper surface of the insulating layer 500 (on the opposite side to the substrate 100). The first conductor 410 and the second conductor 420 are formed on the upper surface of the insulating layer 500 in a way that is larger than the opening width of the first trench 510 and the opening width of the second trench 520. In this embodiment, the protrusions of the first conductor 410 and the second conductor 420 are semi-circular in cross-sectional view, and the cross-sectional shape of the first conductor 410 and the second conductor 420 is mushroom-shaped. However, this is not a limitation; the first conductor 410 and the second conductor 420 may protrude in the direction of the insulating layer 500 and in the stacking direction in the upper surface of the insulating layer 500, as long as they protrude further than the opening width. For example, the protrusions of the first conductor 410 and the second conductor 420 may be formed as cuboids, and the cross-sectional shape of the first conductor 410 and the second conductor 420 may be formed as T-shaped. The height of the stacking direction (D1 direction) of the upper surface of the insulating layer 500 of the first conductor 410 and the second conductor 420 is preferably more than 5% and less than 80% of the height of the stacking direction (D1 direction) of the first trench 510 and the second trench 520.

[0124] Figure 12(C) is a diagram showing the steps of removing the insulating layer 500 in the manufacturing method of the wiring board of this embodiment. As shown in Figure 12(C), the insulating layer 500 on the substrate 100 can be removed by performing a wet treatment using a permanganate solution or N-methyl-2-pyrrolidone, or a dry treatment using oxygen plasma.

[0125] Figure 12(D) illustrates the step of removing the conductive layer 400 in the manufacturing method of the wiring substrate of this embodiment. As shown in Figure 12(D), the conductive layer 400 is etched to expose the upper surface of the substrate 100 by performing a wet process using an aqueous hydrogen peroxide solution. At this time, the first conductor 410 and the second conductor 420 are also formed by etching. By forming the first conductor 410 and the second conductor 420 in this way, the cross-sectional shapes of the first wiring 200 and the second wiring 300 of the aforementioned embodiment and its variations can be formed.

[0126] Although not shown in the figure, the surfaces of the first wiring 200 and the second wiring 300, other than those in contact with the substrate 100, should be blackened. In this embodiment, the blackening treatment is performed by forming an oxide film, namely copper oxide, on the front side (second side) 202 of the first wiring 200 and the front side (fourth side) 304 of the second wiring 300. By blackening the front sides of the first wiring 200 and the second wiring 300, light reflection from the first wiring 200 and the second wiring 300 can be suppressed, and the absorption of external light on the wiring substrate 10 and the contrast can be improved.

[0127] As described above, according to the manufacturing method of the wiring substrate 10 of this embodiment, the conductor can be formed to be thicker in the stacking direction by means of an insulating layer, and the cross-sectional shape of the first wiring 200 and the second wiring 300 of the aforementioned embodiment and its variations can be formed by a simple method such as wet etching. Therefore, a wiring substrate 10 with improved transparency, reliability, and conductivity can be manufactured.

[0128] Next, a modified example of the wiring board manufacturing method will be explained using Figures 13(A)-(D). Figures 13(A)-(D) are diagrams showing a modified example of the wiring board manufacturing method, and are corresponding to Figures 12(A)-(D).

[0129] First, the same steps as shown in Figures 11(A)-(D) above are performed to form the first trench 510 and the second trench 520 that expose the conductive layer 400 (Figure 13(A)).

[0130] Next, as shown in Figure 13(B), a first conductor 410 corresponding to the first wiring 200 and a second conductor 420 (not shown) corresponding to the second wiring 300 are formed. That is, using the conductive layer 400 as a seed layer, copper is used to fill the first trench 510 and the second trench 520 of the insulating layer 500. In this case, the first conductor 410 and the second conductor 420 are formed to be lower than the upper surface of the insulating layer 500 (the opposite side to the substrate 100). At this time, the upper surfaces of the first conductor 410 and the second conductor 420 are formed as semicircles in a cross-sectional view.

[0131] Next, as shown in FIG13(C), the insulating layer 500 on the substrate 100 is removed by performing, for example, a wet treatment using a permanganate solution or N-methyl-2-pyrrolidone, or a dry treatment using oxygen plasma.

[0132] Subsequently, as shown in FIG13(D), the conductive layer 400 is etched to expose the upper surface of the substrate 100 by performing a wet treatment, for example, using an aqueous solution of hydrogen peroxide. At this time, the first conductor 410 and the second conductor 420 are also formed by etching. Specifically, the shape of the first conductor 410 and the second conductor 420 (the shape of the side or the shape of the curved surface, etc.) can be adjusted by appropriately setting the etching conditions (the type of etching solution, the concentration, the etching time, etc.). In this way, the cross-sectional shape of the first wiring 200 and the second wiring 300 in the aforementioned embodiments and their variations can be formed.

[0133] Next, an example of a wireless communication module in which a wireless communication circuit is connected to the wiring board of the aforementioned embodiments and variations will be described. The configuration of the wireless communication module 20A of this embodiment will be explained using FIG14. Here, the parts that are the same as those shown in FIG1 to FIG13 will be omitted in detail.

[0134] [Composition of a wireless communication module] Figure 14 is a top view showing an example of a wireless communication module according to this embodiment. As shown in Figure 14, the wireless communication module 20A has a wiring board 10g and a circuit 700g. The circuit 700g is a wireless communication circuit and is connected to a plurality of first wirings 200g of the wiring board 10g.

[0135] The wiring substrate 10g includes a substrate 100g, a first wiring 200g, and a second wiring 300g. The first wiring 200g and the second wiring 300g are disposed on the upper surface of the substrate 100g. In this embodiment, although four first wirings 200g and four second wirings 300g are disposed, this is not a limitation. It is acceptable as long as two or more first wirings 200g and one or more second wirings 300g are disposed.

[0136] As shown in Figure 14, the planar shape of the first wiring 200g viewed in the D1 direction exemplifies a plurality of lines extending independently from the first side 102 of the substrate 100g toward the second side 104 (the long side direction, the first direction, and the opposite direction of D2 of the first wiring 200g) and forming lines and spaces. The planar shape of the second wiring 300g viewed in the D1 direction exemplifies a plurality of lines extending independently in directions orthogonal to the direction of the first wiring 200g (the long side direction, the second direction, and the D3 direction of the second wiring 300g) and forming lines and spaces. That is, a regular grid or mesh shape can be formed by the first wiring 200g extending in the first direction and the second wiring 300g extending in the second direction. The plurality of first wirings 200g and the plurality of second wirings 300g are orthogonal. The first wiring 200g is longer than the second wiring 300g. Furthermore, the spacing between the plurality of second wirings 300g is greater than the spacing between the plurality of first wirings 200g. However, this shape is not a limitation; the planar shapes of the first wirings 200g and the second wirings 300g can be such that the plurality of lines intersect or connect. For example, the directions of the first wirings 200g and the second wirings 300g can intersect at an acute angle or an obtuse angle. Also, this repeating shape does not need to be uniform on the substrate 100g. Here, when the area on the upper surface of the substrate 100g where the plurality of first wirings 200g and the plurality of second wirings 300g are not disposed is designated as an opening of the wiring substrate 10g, the aperture ratio (visible light transmittance) should preferably be 80% or more. If the aperture ratio is less than 80%, the transmittance of the wiring substrate 10g will deteriorate. By arranging the spacing between the plurality of second wirings 300gs to be larger than the spacing between the plurality of first wirings 200gs, the conductivity of the first wirings 200gs, which have radio wave transmission and reception functions, can be maintained, while the visibility of the second wirings 300gs prepared for breaks in the first wirings 200gs can be suppressed. Therefore, the conductivity and transparency of the wiring substrate 10g can be improved.

[0137] Figure 15 is a top view showing one example of a modified wireless communication module. As shown in Figure 15, the wireless communication module 20A is, for example, a module for NFC (Near Field Communication) and includes a wiring substrate 10g and circuitry 700g. In this case, the wiring substrate 10g, as a whole, has a wiring region 106g formed in a spiral shape in a planar view. This wiring region 106g includes a plurality of first wirings 200g and a plurality of second wirings 300g. That is, inside the wiring region 106g, the first wirings 200g and the second wirings 300g are formed in a grid or lattice pattern. In this case, since the transparency of the wiring substrate 10g can be increased, it becomes possible to arrange, for example, the wiring substrate 10g for NFC on a display screen.

[0138] Furthermore, this disclosure is not limited to the embodiments described above, and appropriate modifications can be made without departing from the spirit of the invention. The embodiments described above, as embodiments of this disclosure, can be appropriately combined to implement them, provided they do not contradict each other. Moreover, based on the wiring board of each embodiment, embodiments in which those skilled in the art have made appropriate additions, deletions, or design changes to constituent elements, or embodiments in which steps have been added, omitted, or conditions have been changed, are still included within the scope of this invention, as long as they possess the spirit of the invention.

[0139] Even if the effects are different from those brought about by the various embodiments described above, the effects that can be known from the description in this specification or that can be easily predicted by those skilled in the art to which this invention pertains can of course be understood as effects brought about by this invention.

[0140] [Example] The structure of the first wiring 200 and the second wiring 300 of the wiring substrate of one embodiment disclosed herein will be explained in more detail.

[0141] [Reference Example 1] The parameters of the first wiring 200 and the second wiring 300 in the wiring board of Example 1 are as follows. Width of the first wiring 200: 1μm Height of wiring 200: 1μm The spacing of the first wiring 200 is 20μm. Width of the second wiring 300: 2μm Height of second wiring 300: 1μm The spacing of the second wiring 300 is 20μm.

[0142] Since the wiring substrate of Reference Example 1 disclosed herein is the same as the wiring substrate of Modified Example 6 (Figs. 9 and 10) except for the width and spacing (pitch) of each wire, its detailed description is omitted. Since the manufacturing steps of the wiring substrate are the same as those shown in Figs. 11 to 13, the description is also omitted.

[0143] Using the wiring board of Reference Example 1, the intersection of the first wiring 200 and the second wiring 300 was observed using a electron microscope (SEM). A photograph of the upper surface of the wiring board of Reference Example 1 observed using an electron microscope (SEM) is shown in Figure 16. A photograph of the intersection of the first wiring 200 and the second wiring 300 of Reference Example 1 observed using an electron microscope (SEM) is shown in Figure 17.

[0144] Figure 17 is an electron microscope photograph of the intersection of the first wiring 200 and the second wiring 300 in Reference Example 1. As shown in Figures 17(A) and (B), the wiring substrate 10 of Reference Example 1 includes two curved surfaces at the intersection of the first wiring 200 and the second wiring 300. A curved surface f, which continuously bends these surfaces, can be observed at the corner formed by the upper surface of the substrate 100, the side surface 209 of one side of the first wiring 200, and the side surface 306 of the other side of the second wiring 300. Furthermore, a curved surface f, which continuously bends these surfaces, can be observed at the corner formed by the upper surface of the substrate 100, the side surface 210 of the other side of the first wiring 200, and the side surface 306 of the other side of the second wiring 300.

[0145] <Second Implementation Form> Next, the second embodiment will be explained with reference to Figures 18 to 37. Figures 18 to 37 are diagrams showing the second embodiment.

[0146] In this embodiment, the "X direction" is a direction perpendicular to the long side of the antenna pattern area and perpendicular to the length corresponding to the frequency band of the antenna wiring. The "Y direction" is a direction perpendicular to the X direction and parallel to the long side of the antenna pattern area and parallel to the length corresponding to the frequency band of the antenna wiring. The "Z direction" is a direction perpendicular to both the X and Y directions and parallel to the thickness direction of the wiring substrate. Furthermore, "front side" refers to the surface on the positive side of the Z direction, specifically the surface where the antenna wiring is disposed relative to the substrate. "Back side" refers to the surface on the negative side of the Z direction, specifically the surface opposite to the surface where the antenna wiring is disposed relative to the substrate. Moreover, although this embodiment uses the case where the wiring pattern area 20 is an antenna pattern area 20 with radio wave transmission and reception function (functioning as an antenna) as an example for explanation, the wiring pattern area 20 may also not have radio wave transmission and reception function (functioning as an antenna).

[0147] [Structure of the wiring board] The configuration of the wiring board of this embodiment will be described with reference to Figures 18 to 22. Figures 18 to 22 are diagrams showing the wiring board of this embodiment.

[0148] As shown in FIG18, the wiring board 10 of this embodiment is disposed on a display, such as an image display device. This wiring board 10 includes: a substrate 11, which is transparent; an antenna pattern region (wiring pattern region) 20 disposed on the substrate 11; and a dummy pattern region 30 disposed on the substrate 11 around the antenna pattern region 20. Furthermore, a power supply unit 40 is electrically connected to the antenna pattern region 20.

[0149] In this embodiment, substrate 11 is formed to be approximately rectangular in planar view, with its long side parallel to the Y-direction and its short side parallel to the X-direction. Substrate 11 is transparent and approximately flat, and its thickness is generally uniform. The length L1 of the long side (Y-direction) of substrate 11 can be selected, for example, in the range of 100 mm or more and 200 mm or less, and the length L2 of the short side (X-direction) of substrate 11 can be selected, for example, in the range of 50 mm or more and 100 mm or less.

[0150] The material of substrate 11 can be any material that is transparent in the visible light region and electrically insulating. In this embodiment, the material of substrate 11 is polyethylene terephthalate, but it is not limited to this. As the material of substrate 11, it is preferable to use organic insulating materials such as polyester resins such as polyethylene terephthalate, acrylic resins such as polymethyl methacrylate, polycarbonate resins, polyimide resins, or polyolefin resins such as cyclic olefin polymers, or cellulose resins such as cellulose triacetate. Furthermore, as the material of substrate 11, glass, ceramics, etc., can be appropriately selected according to the application. Moreover, although the illustration shows an example of substrate 11 being constructed by a single layer, it is not limited to this, and it can also be a structure composed of multiple substrates or layers. Furthermore, substrate 11 can be in the form of a thin film or a plate. Therefore, although there is no particular limitation on the thickness of the substrate 11, and it can be appropriately selected according to the application, as an example, the thickness (Z direction) T1 of the substrate 11 (see Figure 20) can be set to, for example, a range of 10 μm or more and 200 μm or less.

[0151] In Figure 18, a plurality of antenna pattern regions 20 (3 in total) are formed on the substrate 11, each corresponding to a different frequency band. That is, the lengths (lengths in the Y direction) La of the plurality of antenna pattern regions 20 are different from each other, and each has a length corresponding to a specific frequency band. Furthermore, the lower the frequency band, the longer the length La of the antenna pattern region 20 becomes. When the wiring substrate 10 is disposed on, for example, the display 91 of the image display device 90 (see Figure 24 described later), if each antenna pattern region 20 has radio wave transmission and reception functions, it can correspond to any one of the following: telephone antenna, WiFi antenna, 3G antenna, 4G antenna, LTE antenna, Bluetooth antenna, NFC antenna, etc. Alternatively, if the wiring substrate 10 does not have radio wave transmission and reception functions, each wiring pattern region 20 can also perform functions such as hovering (the function that allows the user to operate the display without directly touching it), fingerprint authentication, heating, noise reduction (shielding), etc.

[0152] Each antenna pattern region 20 is approximately rectangular in planar view. Each antenna pattern region 20 is formed such that its long side is parallel to the Y-direction and its short side is parallel to the X-direction. The length La of the long side (Y-direction) of each antenna pattern region 20 can be selected in the range of, for example, 3 mm or more and 100 mm or less, and the width Wa of the short side (X-direction) of each antenna pattern region 20 can be selected in the range of, for example, 1 mm or more and 10 mm or less.

[0153] The antenna pattern region 20 is formed by forming metal wires into a grid shape or a mesh shape, and has a uniform repeating pattern in both the X and Y directions. That is, as shown in FIG19, the antenna pattern region 20 is composed of repeating L-shaped unit pattern shapes 20a, wherein the aforementioned unit pattern shape 20a is composed of a portion extending in the X direction (a part of the antenna connection wiring 22 described later) and a portion extending in the Y direction (a part of the antenna wiring 21 described later).

[0154] As shown in Figure 19, each antenna pattern area 20 includes a plurality of antenna wirings 21 that function as antennas, and a plurality of antenna connection wirings 22 connecting the plurality of antenna wirings 21. Specifically, the plurality of antenna wirings 21 and the plurality of antenna connection wirings 22 are integrated as a whole and form a regular grid or mesh shape. Each antenna wiring 21 extends in a direction corresponding to the antenna's frequency band (Y direction), and each antenna connection wiring 22 extends in a direction orthogonal to the antenna wiring 21 (X direction). The antenna wirings 21 function primarily as antennas by having a length La corresponding to a predetermined frequency band (the length of the aforementioned antenna pattern area 20). On the other hand, the antenna connection wirings 22, by connecting these antenna wirings 21 to each other, serve to suppress the failure of antenna wirings 21 to break or the antenna wirings 21 to become disconnected from the power supply unit 40.

[0155] In each antenna pattern area 20, a plurality of openings 23 are formed by being surrounded by adjacent antenna wirings 21 and adjacent antenna connection wirings 22. Furthermore, the antenna wirings 21 and antenna connection wirings 22 are arranged at equal intervals. That is, the plurality of antenna wirings 21 are arranged at equal intervals, and their spacing P1 can be set to, for example, a range of 0.01 mm or more and 1 mm or less. Similarly, the plurality of antenna connection wirings 22 are arranged at equal intervals, and their spacing P2 can be set to, for example, a range of 0.01 mm or more and 1 mm or less. Thus, by arranging the plurality of antenna wirings 21 and the plurality of antenna connection wirings 22 at equal intervals, the size of the openings 23 in each antenna pattern area 20 will not be inconsistent, making the antenna pattern areas 20 difficult to see with the naked eye. Furthermore, the spacing P1 of the antenna wirings 21 is equal to the spacing P2 of the antenna connection wirings 22. Therefore, each opening 23 is approximately square in planar view, and a transparent substrate 11 is exposed through each opening 23. Thus, by making the area of ​​each opening 23 larger, the overall transparency of the wiring substrate 10 can be improved. Furthermore, the length L3 of one side of each opening 23 can be set to, for example, a range of 0.01 μm or more and 1 μm or less. Furthermore, although each antenna wiring 21 and each antenna connection wiring 22 are orthogonal to each other, they are not limited to this and can also intersect at acute or obtuse angles. Also, the shape of the opening 23 should preferably be the same shape and size throughout the entire surface, but it can be changed depending on the location, etc., rather than being uniform across the entire surface.

[0156] As shown in Figure 20, each antenna wiring 21 is formed with a cross-section (X-direction cross-section) perpendicular to its long side direction as approximately rectangular or square. In this case, the cross-sectional shape of the antenna wiring 21 is approximately uniform along the long side direction (Y-direction) of the antenna wiring 21. Also, as shown in Figure 21, the cross-section (Y-direction cross-section) perpendicular to the long side direction of each antenna connection wiring 22 is approximately rectangular or square, and is approximately the same as the cross-sectional shape (X-direction cross-section) of the antenna wiring 21. In this case, the cross-sectional shape of the antenna connection wiring 22 is approximately uniform along the long side direction (X-direction) of the antenna connection wiring 22. The cross-sectional shapes of the antenna wiring 21 and antenna connection wiring 22 do not necessarily have to be approximately rectangular or square; they can also be, for example, approximately trapezoidal in shape where the front side (positive Z-direction side) is narrower than the back side (negative Z-direction side), or curved on both sides along the long side direction.

[0157] In this embodiment, the line width W1 (length in the X direction, see Figure 20) of the antenna wiring 21 and the line width W2 (length in the Y direction, see Figure 21) of the antenna connecting wiring 22 are not particularly limited and can be appropriately selected according to the application. For example, the line width W1 of the antenna wiring 21 can be selected in the range of 0.1 μm or more and 5.0 μm or less, and the line width W2 of the antenna connecting wiring 22 can be selected in the range of 0.1 μm or more and 5.0 μm or less. Furthermore, the height H1 (length in the Z direction, see Figure 20) of the antenna wiring 21 and the height H2 (length in the Z direction, see Figure 21) of the antenna connecting wiring 22 are not particularly limited and can be appropriately selected according to the application, and can be selected in the range of, for example, 0.1 μm or more and 5.0 μm or less.

[0158] The antenna wiring 21 and antenna connection wiring 22 can be made of any conductive metallic material. In this embodiment, although the material of antenna wiring 21 and antenna connection wiring 22 is copper, it is not a limitation. The material of antenna wiring 21 and antenna connection wiring 22 can be, for example, alloys of metals including gold, silver, copper, platinum, tin, aluminum, iron, and nickel.

[0159] Referring again to Figure 18, the dummy pattern region 30 is configured to surround each antenna pattern region 20, and is formed to surround the entire peripheral area of ​​each antenna pattern region 20 except for the power supply section 40 side (Y-direction negative side) (X-direction positive side, X-direction negative side, Y-direction positive side). In this case, the dummy pattern region 30 is configured on the substrate 11 and covers approximately the entire area except for the antenna pattern region 20 and the power supply section 40. This dummy pattern region 30 is different from the antenna pattern region 20 and does not actually function as an antenna.

[0160] As shown in Figure 19, the dummy pattern region 30 is composed of repetitions of dummy wirings 30a with a predetermined unit pattern shape. That is, the dummy pattern region 30 includes a plurality of dummy wirings 30a of the same shape, each dummy wiring 30a being electrically independent of the antenna pattern region 20 (antenna wiring 21 and antenna connection wiring 22). Furthermore, the plurality of dummy wirings 30a are regularly arranged to cover the entire area within the dummy pattern region 30. The plurality of dummy wirings 30a are separated from each other in the planar direction and protrude from the substrate 11, arranged in an island-like shape. That is, each dummy wiring 30a is electrically independent of the antenna pattern region 20, the power supply section 40, and other dummy wirings 30a. From a planar perspective, each dummy wiring 30a is approximately L-shaped and has a first dummy wiring portion 31 extending in the Y direction and a second dummy wiring portion 32 extending in the X direction. In this process, the first dummy wiring portion 31 has a predetermined length L4 (length in the Y direction), and the second dummy wiring portion 32 has a predetermined length L5 (length in the X direction), and these lengths are equal to each other (L4=L5).

[0161] Adjacent dummy wirings 30a in the X direction have gaps 33a between them, and adjacent dummy wirings 30a in the Y direction have gaps 33b between them. In this case, the dummy wirings 30a are arranged at equal intervals. That is, adjacent dummy wirings 30a in the X direction can be arranged at equal intervals, with the interval G1 set to, for example, a range of 1 μm or more and 20 μm or less. Similarly, adjacent dummy wirings 30a in the Y direction can be arranged at equal intervals, with the interval G2 set to, for example, a range of 1 μm or more and 20 μm or less. Furthermore, the maximum values ​​of intervals G1 and G2 can also be set to less than 0.8 times the aforementioned distances P1 and P2, respectively. In this case, the interval G1 in the X direction of the dummy wirings 30a is equal to the interval G2 in the Y direction of the dummy wirings 30a (G1=G2).

[0162] In this embodiment, the dummy wiring 30a has a shape that is partially missing from the unit pattern shape 20a of the antenna pattern region 20. That is, the shape of the dummy wiring 30a is the L-shaped unit pattern shape 20a of the antenna pattern region 20, with the aforementioned gaps 33a and 33b removed. In other words, the shape formed by combining a plurality of dummy wirings 30a and a plurality of gaps 33a and 33b of the dummy pattern region 30 is equivalent to forming a grid shape or mesh shape of the antenna pattern region 20. Thus, by making the dummy wiring 30a of the dummy pattern region 30 a shape that is partially missing from the unit pattern shape 20a of the antenna pattern region 20, the difference between the antenna pattern region 20 and the dummy pattern region 30 becomes difficult to distinguish visually, and the antenna pattern region 20 disposed on the substrate 11 becomes difficult to see.

[0163] In Figure 19, the antenna pattern region 20 and the dummy pattern region 30 are adjacent in the Y direction. Near the boundary between the antenna pattern region 20 and the dummy pattern region 30, the first dummy wiring portion 31 is formed on the extension of the antenna wiring 21. Therefore, the difference between the antenna pattern region 20 and the dummy pattern region 30 becomes difficult to see visually. Furthermore, although not shown, in places where the antenna pattern region 20 and the dummy pattern region 30 are adjacent in the X direction, it is also advisable to form the second dummy wiring portion 32 on the extension of the antenna connection wiring 22 for the same reason.

[0164] As shown in Figure 22, the first dummy wiring portion 31 of each dummy wiring 30a has a cross-section (X-direction cross-section) perpendicular to its long side direction (Y-direction) that is approximately rectangular or approximately square. Similarly, as shown in Figure 21, the second dummy wiring portion 32 of each dummy wiring 30a has a cross-section (Y-direction cross-section) perpendicular to its long side direction (X-direction) that is approximately rectangular or approximately square. In this case, the cross-sectional shape of the first dummy wiring portion 31 is approximately the same as the cross-sectional shape of the antenna wiring 21, and the cross-sectional shape of the second dummy wiring portion 32 is approximately the same as the cross-sectional shape of the antenna connection wiring 22.

[0165] In this embodiment, the line width W3 (length in the X direction, see Figure 22) of the first dummy wiring portion 31 is approximately the same as the line width W1 of the antenna wiring 21, and the line width W4 (length in the Y direction, see Figure 21) of the second dummy wiring portion 32 is approximately the same as the line width W2 of the antenna connection wiring 22. Furthermore, the height H3 (length in the Z direction, see Figure 22) of the first dummy wiring portion 31 and the height H4 (length in the Z direction, see Figure 21) of the second dummy wiring portion 32 are also formed to be approximately the same as the height H1 of the antenna wiring 21 and the height H2 of the antenna connection wiring 22, respectively.

[0166] The material of the dummy wiring 30a can be the same metal material as that of the antenna wiring 21 and the antenna connection wiring 22.

[0167] However, in this embodiment, the antenna pattern region 20 and the dummy pattern region 30 each have predetermined aperture ratios A1 and A2. The aperture ratio A1 of the antenna pattern region 20 can be set to, for example, a range of 85% or more and 99.9% or less. Similarly, the aperture ratio A2 of the dummy pattern region 30 can be set to, for example, a range of 87% or more and less than 100%. In this case, the aperture ratio A2 of the dummy pattern region 30 is greater than the aperture ratio A1 of the antenna pattern region 20 (A2>A1). This ensures the transparency of the wiring board 10. Furthermore, not limited to this, the aperture ratio A2 of the dummy pattern region 30 can also be smaller than the aperture ratio A1 of the antenna pattern region 20 (A2>A1). <A1)。

[0168] Furthermore, the difference (|A2-A1|) between the aperture ratio A2 of the dummy pattern region 30 and the aperture ratio A1 of the antenna pattern region 20 should preferably be set to a range greater than 0% and less than 7%, and more preferably to a range greater than 0% and less than 1%. In this way, by setting the difference between the aperture ratio A2 of the dummy pattern region 30 and the aperture ratio A1 of the antenna pattern region 20 to be smaller, the boundary between the antenna pattern region 20 and the dummy pattern region 30 can be made difficult to see, thus making it difficult to identify the existence of the antenna pattern region 20 with the naked eye.

[0169] Furthermore, the overall aperture ratio A3 of the antenna pattern region 20 and the dummy pattern region 30 (the combined aperture ratio of the antenna pattern region 20 and the dummy pattern region 30) can be set to, for example, a range of 87% or more and less than 100%. By setting the overall aperture ratio A3 of the wiring board 10 to this range, the conductivity and transparency of the wiring board 10 can be ensured.

[0170] Furthermore, the aperture ratio refers to the percentage (%) of the area occupied by the open area (the area where the metal parts of the antenna wiring 21, antenna connection wiring 22, dummy wiring 30a, etc. are absent and the substrate 11 is exposed) in a predetermined area (antenna pattern area 20, dummy pattern area 30, or antenna pattern area 20 and dummy pattern area 30).

[0171] Referring again to Figure 18, the power supply unit 40 is electrically connected to the antenna pattern area 20. This power supply unit 40 is formed of a generally rectangular conductive thin plate-like member. The long side of the power supply unit 40 is parallel to the X direction, and the short side of the power supply unit 40 is parallel to the Y direction. Furthermore, the power supply unit 40 is disposed at the end of the long side direction (the negative end in the Y direction) of the substrate 11. The material of the power supply unit 40 can be, for example, metal materials (alloys) including gold, silver, copper, platinum, tin, aluminum, iron, nickel, etc. When the wiring board 10 is assembled into the image display device 90 (see Figure 24), this power supply unit 40 is electrically connected to the wireless communication circuit 92 of the image display device 90. Moreover, although the power supply unit 40 is disposed on the surface of the substrate 11, it is not limited thereto; part or all of the power supply unit 40 may be located further outward than the periphery of the substrate 11.

[0172] [Manufacturing Method of Wiring Board] Next, the manufacturing method of the wiring board of this embodiment will be described with reference to Figures 23(a)-(h). Figures 23(a)-(h) are cross-sectional views showing the manufacturing method of the wiring board of this embodiment.

[0173] First, as shown in FIG23(a), a substrate 11 is prepared, and a conductive layer 51 is formed over approximately the entire surface area of ​​this substrate 11. In this embodiment, the thickness of the conductive layer 51 is 200 nm. However, it is not limited to this, and the thickness of the conductive layer 51 can be appropriately selected in the range of 10 nm or more and 1000 nm or less. In this embodiment, the conductive layer 51 is formed using copper by sputtering. As a method for forming the conductive layer 51, plasma chemical vapor deposition (plasma CVD) can also be used.

[0174] Next, as shown in FIG23(b), a photocurable insulating resist 52 is supplied to approximately the entire surface area of ​​the substrate 11. Examples of this photocurable insulating resist 52 include organic resins such as epoxy resins.

[0175] Next, a transparent stamping mold 53 with protrusions 53a is prepared (Fig. 23(c)). This mold 53 is brought close to the substrate 11 so that the photocurable insulating resist 52 is spread between the mold 53 and the substrate 11. Then, by irradiating light from the mold 53 side, the photocurable insulating resist 52 is cured to form an insulating layer 54. Thereby, a groove 54a with the shape of the transferred protrusions 53a is formed on the surface of the insulating layer 54. The groove 54a has a planar shape pattern corresponding to the antenna wiring 21, the antenna connection wiring 22, and the dummy wiring 30a.

[0176] Then, by peeling the mold 53 from the insulating layer 54, the insulating layer 54 with the cross-sectional structure shown in FIG23(d) is obtained. The direction in which the mold 53 is peeled from the insulating layer 54 should preferably be the Y direction of the extension of the longer antenna wiring 21.

[0177] Thus, the trench 54a can be formed on the surface of the insulating layer 54 by imprinting, and the shape of the trench 54a can be set to a finer shape. Furthermore, not limited to this, the insulating layer 54 can also be formed by photolithography. In this case, the resist pattern is formed by photolithography to expose the conductive layer 51 corresponding to the antenna wiring 21, the antenna connection wiring 22, and the dummy wiring 30a.

[0178] As shown in Figure 23(d), there may be residual insulating material at the bottom of the trench 54a of the insulating layer 54. Therefore, the residual insulating material can be removed by wet treatment using permanganate solution or N-methyl-2-pyrrolidone, or by dry treatment using oxygen plasma. In this way, by removing the residual insulating material, the trench 54a exposing the conductive layer 51 can be formed as shown in Figure 23(e).

[0179] Next, as shown in FIG23(f), the trench 54a of the insulating layer 54 is filled with a conductor 55. In this embodiment, the conductive layer 51 is used as a seed layer, and the trench 54a of the insulating layer 54 is filled with copper using an electrolytic plating method.

[0180] Next, as shown in FIG23(g), the insulating layer 54 is removed. In this case, the insulating layer 54 on the substrate 11 can be removed by performing a wet treatment using a permanganate solution or N-methyl-2-pyrrolidone, or a dry treatment using oxygen plasma.

[0181] Next, as shown in FIG23(h), the conductive layer 51 on the surface of the substrate 11 is removed. At this time, the conductive layer 51 is etched to expose the surface of the substrate 11 by performing a wet process using an aqueous hydrogen peroxide solution. This process is repeated to obtain a wiring substrate 10, which has a substrate 11 and an antenna pattern region 20 and a dummy pattern region 30 disposed on the substrate 11. In this case, the antenna pattern region 20 includes antenna wiring 21 and antenna connection wiring 22, and the dummy pattern region 30 includes dummy wiring 30a. The conductor 55 includes antenna wiring 21, antenna connection wiring 22, and dummy wiring 30a.

[0182] [The function of this implementation] Next, the function of the wiring board formed by such a configuration will be explained.

[0183] As shown in Figure 24, the wiring board 10 is incorporated into an image display device 90 having a display 91. The wiring board 10 is disposed on the display 91. Examples of such image display devices 90 include mobile terminal devices such as smartphones and tablet computers. The antenna pattern area 20 of the wiring board 10 is electrically connected to the wireless communication circuit 92 of the image display device 90 through the power supply unit 40. In this way, radio waves of a predetermined frequency can be transmitted and received through the antenna pattern area 20, and communication can be performed using the image display device 90. Furthermore, since the dummy pattern area 30 is separate from the antenna pattern area 20 and is electrically independent, there is no concern that the presence of the dummy pattern area 30 will affect the transmission and reception of radio waves.

[0184] According to this embodiment, since the wiring board 10 has: a substrate 11 that is transparent; and an antenna pattern area 20 disposed on the substrate 11 and including a plurality of antenna wirings 21 that function as antennas, the transparency of the wiring board 10 can be ensured. Therefore, since the display 91 can be seen through the opening 23 of the antenna pattern area 20 when the wiring board 10 is disposed on the display 91, there is no obstruction to the visibility of the display 91.

[0185] Furthermore, according to this embodiment, a dummy pattern area 30 is arranged around the antenna pattern area 20. The aforementioned dummy pattern area 30 includes a plurality of dummy lines 30a electrically independent of the antenna wiring 21. Thus, by arranging the dummy pattern area 30 around the antenna pattern area 20, the boundary between the antenna pattern area 20 and other areas becomes less clear. This makes the antenna pattern area 20 difficult to see on the front of the display 91, and makes it difficult for the user of the image display device 90 to identify the antenna pattern area 20 with the naked eye.

[0186] Furthermore, according to this embodiment, the antenna pattern area 20 and the dummy pattern area 30 are each composed of a repetition of a predetermined unit pattern shape. The unit pattern shape (dummy wiring 30a) of the dummy pattern area 30 is a shape that is missing a portion of the unit pattern shape 20a of the antenna pattern area 20. In this way, the boundary between the antenna pattern area 20 and the dummy pattern area 30 becomes less unclear, and the antenna pattern area 20 becomes difficult to distinguish with the naked eye on the front of the display 91.

[0187] Furthermore, according to this embodiment, the aperture ratio A2 of the dummy pattern region 30 is greater than the aperture ratio A1 of the antenna pattern region 20. This makes the antenna pattern region 20 difficult to identify and ensures the transparency of the wiring substrate 10.

[0188] Furthermore, according to this embodiment, the antenna pattern area 20 includes a plurality of antenna connection lines 22 connecting a plurality of antenna lines 21. This makes the antenna lines 21 less prone to breakage and suppresses any reduction in the antenna function of the antenna lines 21.

[0189] (Modified Example) Next, various modifications of the wiring board will be described with reference to Figures 25 to 37. Figures 25 to 37 are diagrams showing various modifications of the wiring board. The modifications shown in Figures 25 to 37 are modifications in which the antenna pattern area 20 and / or the dummy pattern area 30 are configured differently, while other configurations are generally the same as the embodiments described above. In Figures 25 to 37, the same symbols are added to the parts that are the same as those shown in Figures 18 to 24, and detailed descriptions are omitted.

[0190] (Variation Example 1) Figure 25 shows the wiring substrate 10A of Modified Example 1. In Figure 25, the dummy pattern region 30 of the wiring substrate 10A includes a plurality of dummy wirings 30a having a predetermined unit pattern shape. Each dummy wiring 30a is electrically independent of the antenna pattern region 20 (antenna wiring 21 and antenna connection wiring 22). Each dummy wiring 30a has a first dummy wiring portion 31 extending in the Y direction and a second dummy wiring portion 32 extending in the X direction. In this case, the first dummy wiring portion 31 and the second dummy wiring portion 32 of each dummy wiring 30a are arranged separately from each other in the planar direction.

[0191] A gap 33c is formed between the first dummy wiring portion 31 and the second dummy wiring portion 32 of each dummy wiring 30a. Furthermore, assuming that the gap 33c has been filled in the dummy wiring 30a, gaps 33a and 33b are formed between adjacent dummy wiring 30a in the X direction and between adjacent dummy wiring 30a in the Y direction, respectively. The dummy wiring 30a of the dummy pattern region 30 has a shape that lacks a portion of the unit pattern shape 20a of the antenna pattern region 20. That is, the shape of the dummy wiring 30a is a shape obtained by removing the gaps 33a, 33b, and 33c from the L-shaped unit pattern shape 20a of the antenna pattern region 20. Furthermore, the aperture ratio A2 of the dummy pattern region 30 can be set to, for example, a range of 85% or more and less than 100%.

[0192] In this way, by separating the first dummy wiring portion 31 and the second dummy wiring portion 32 of each dummy wiring 30a in the planar direction, the aperture ratio of the dummy pattern area 30 can be further improved, and the transparency of the wiring substrate 10A can be enhanced.

[0193] (Variation Example 2) FIG. 26 shows the wiring substrate 10B of Modification 2. In FIG. 26, the dummy pattern region 30 of the wiring substrate 10B includes a plurality of dummy wirings 30a having a predetermined unit pattern shape. Each dummy wiring 30a is electrically independent of the antenna pattern region 20 (antenna wiring 21 and antenna connection wiring 22). This dummy wiring 30a has a first dummy wiring portion 31 and a second dummy wiring portion 32 that obliquely extend with respect to the X direction and the Y direction, respectively. The first dummy wiring portion 31 and the second dummy wiring portion 32 of each dummy wiring 30a are arranged separately from each other in the planar direction. In this case, the long side direction of the first dummy wiring portion 31 is arranged to be inclined 45° with respect to the long side direction of the antenna wiring 21. Also, the long side direction of the second dummy wiring portion 32 is in a direction orthogonal to the long side direction of the first dummy wiring portion 31. Furthermore, the aperture ratio A2 of the dummy pattern region 30 can be set in a range of, for example, 85% or more and less than 100%.

[0194] Thus, by arranging the first dummy wiring portion 31 and the second dummy wiring portion 32 of each dummy wiring 30a obliquely with respect to the antenna wiring 21, the generation of interference fringes formed by the diffraction grating can be suppressed.

[0195] (Modification 3) FIG. 27 shows the wiring substrate 10C of Modification 3. In FIG. 27, the antenna pattern region 20 of the wiring substrate 10C includes a plurality of antenna wirings 21 having the function of an antenna, and a plurality of antenna connection wirings 22 connecting the plurality of antenna wirings 21. In this case, the pitch P1 of the antenna wirings 21 is smaller than the pitch P2 of the antenna connection wirings 22 (P1 < P2). For example, the pitch P1 of the antenna wirings 21 can be set in a range of 0.01 mm or more and 1 mm or less, and the pitch P2 of the antenna connection wirings 22 can be set in a range of, for example, 0.03 mm or more and 1 mm or less. Also, each opening 23 has a substantially rectangular shape that is longer in the Y direction than in the X direction in a planar view. Thus, by making the area of each opening 23 larger, the transparency of the entire wiring substrate 10C can be further improved.

[0196] Furthermore, the dummy pattern region 30 includes a plurality of dummy wirings 30a having a predetermined unit pattern shape. Each dummy wiring 30a is electrically independent of the antenna pattern region 20 (antenna wiring 21 and antenna connection wiring 22). Each dummy wiring 30a has a pair of first dummy wiring portions 31a and 31b extending in the Y direction and a second dummy wiring portion 32 extending in the X direction. In this case, the first dummy wiring portions 31a, 31b, and 32 of each dummy wiring 30a are arranged separately from each other in the planar direction.

[0197] A gap 33c is formed between the first dummy wiring portion 31a and the second dummy wiring portion 32 of each dummy wiring 30a. Furthermore, a gap 33d is formed between the first dummy wiring portions 31a and 31b. Moreover, assuming that the gaps 33c and 33d have been filled in the dummy wirings 30a, gaps 33a and 33b are formed between adjacent dummy wirings 30a in the X direction and between adjacent dummy wirings 30a in the Y direction, respectively. In this case, the dummy wirings 30a of the dummy pattern region 30 have a shape that lacks a portion of the unit pattern shape 20a of the antenna pattern region 20. That is, the shape of the dummy wirings 30a is a shape obtained by removing the gaps 33a to 33d from the L-shaped unit pattern shape 20a of the antenna pattern region 20. Furthermore, the aperture ratio A2 of the dummy pattern region 30 can be set to, for example, a range of more than 90% and less than 100%.

[0198] In this way, the transparency of the wiring substrate 10C can be improved by increasing the size of the opening areas (areas where the metal parts of the antenna pattern area 20, antenna connection wiring 22, dummy wiring 30a, etc. are absent, and the substrate 11 is exposed) of the antenna pattern area 20 and the dummy pattern area 30.

[0199] (Variation Example 4) Figure 28 shows the wiring substrate 10D of Modified Example 4. In Figure 28, the dummy pattern region 30 of the wiring substrate 10D includes a plurality of dummy wirings 30a having a predetermined unit pattern shape. Each dummy wiring 30a is electrically independent of the antenna pattern region 20 (antenna wiring 21 and antenna connection wiring 22). This dummy wiring 30a has a pair of first dummy wiring portions 31a and 31b extending obliquely relative to the X and Y directions, respectively, and a second dummy wiring portion 32 extending obliquely relative to the X and Y directions. The first dummy wiring portions 31a, 31b, and 32 of each dummy wiring 30a are arranged separately from each other in the planar direction. In this case, the long side direction of the pair of first dummy wiring portions 31a and 31b is arranged at an angle of 45° relative to the long side direction of the antenna wiring 21. Furthermore, the long side direction of the second dummy wiring portion 32 is located in a direction orthogonal to the long side directions of each of the first dummy wiring portions 31a and 31b. Moreover, the aperture ratio A2 of the dummy pattern region 30 can be set to, for example, a range of 90% or more and less than 100%.

[0200] Thus, by arranging the first dummy wiring portions 31a, 31b and the second dummy wiring portion 32 of each dummy wiring 30a obliquely relative to the antenna wiring 21, the generation of interference fringes formed by the diffraction grating can be suppressed.

[0201] (Variation Example 5) Figure 29 shows the wiring substrate 10E of Modified Example 5. In Figure 29, the dummy pattern region 30 of the wiring substrate 10E includes a plurality of dummy wirings 30a having a predetermined unit pattern shape. Each dummy wiring 30a is electrically independent of the antenna pattern region 20 (antenna wiring 21 and antenna connection wiring 22). Each dummy wiring 30a has a plurality (4) of first dummy wiring portions 31c extending in the Y direction and a plurality (4) of second dummy wiring portions 32c extending in the X direction. In this case, the plurality of first dummy wiring portions 31c are arranged separately from each other in the Y direction, and the plurality of second dummy wiring portions 32c are arranged separately from each other in the X direction.

[0202] A gap 33e is formed at the intersection between the first dummy wiring portion 31a and the second dummy wiring portion 32c of the dummy wiring 30a. Furthermore, gaps 33f are formed between a plurality of first dummy wiring portions 31c. Moreover, gaps 33g are formed between a plurality of second dummy wiring portions 32c. In this case, the dummy wiring 30a of the dummy pattern region 30 has a shape that lacks a portion of the unit pattern shape 20a of the antenna pattern region 20. That is, the shape of the dummy wiring 30a is a shape obtained by removing the gaps 33e to 33g from the L-shaped unit pattern shape 20a of the antenna pattern region 20.

[0203] In this modified example, an additional pattern 34, separate from the dummy wiring 30a of the dummy pattern region 30, is arranged within the dummy pattern region 30. In this case, the additional pattern 34 is arranged separately from a plurality of first dummy wiring portions 31c and a plurality of second dummy wiring portions 32c in both the X and Y directions. In this case, each additional pattern 34 extends linearly parallel to the Y direction. Furthermore, a plurality (4) of additional patterns 34 are arranged relative to each dummy wiring 30a. The total area of ​​these plurality (4) of additional patterns 34 should preferably be close to the area of ​​the gaps 33e to 33g of each dummy wiring 30a. Moreover, the material of the additional pattern 34 can be the same metal material as the material of the dummy wiring 30a.

[0204] Thus, by arranging an additional pattern 34 within the dummy pattern region 30, the difference (|A2-A1|) between the aperture ratio A2 of the dummy pattern region 30 and the aperture ratio A1 of the antenna pattern region 20 can be made close to 0. Specifically, the difference between the aperture ratios A2 and A1 can be set to a range of 0% or more and 1% or less. This makes the boundary between the antenna pattern region 20 and the dummy pattern region 30 less clear and makes the antenna pattern region 20 difficult to distinguish with the naked eye.

[0205] (Variation Example 6) Figure 30 shows the wiring substrate 10F of Modified Example 6. In Figure 30, additional patterns 34, separate from the dummy wirings 30a of the dummy pattern region 30, are arranged within the dummy pattern region 30. In this case, each additional pattern 34 extends in a straight line and is inclined relative to the X and Y directions, respectively. Furthermore, in Figure 30, a plurality of (4) additional patterns 34 are arranged relative to one dummy wiring 30a. The other configurations are substantially the same as those of the wiring substrate 10E (Modified Example 5) shown in Figure 29.

[0206] (Variation Example 7) Figure 31 shows the wiring substrate 10G of Modified Example 7. In Figure 31, the dummy wirings 30a each have a plurality of (2) first dummy wiring portions 31c extending in the Y direction and a plurality of (2) second dummy wiring portions 32c extending in the X direction. Furthermore, each additional pattern 34 extends in a straight line and is inclined relative to both the X and Y directions. In this case, a plurality of (2) additional patterns 34 are arranged relative to each dummy wiring 30a. The other configurations are substantially the same as those of the wiring substrate 10E (Modified Example 5) shown in Figure 29.

[0207] (Variation Example 8) Figure 32 shows the wiring substrate 10H of Modified Example 8. In Figure 32, the dummy wiring 30a has a plurality of (2) first dummy wiring portions 31c extending in the Y direction and a plurality of (2) second dummy wiring portions 32c extending in the X direction. Among these, one first dummy wiring portion 31c and one second dummy wiring portion 32c are connected to each other and form an L-shape in a planar view. In this case, each additional pattern 34 extends parallel and linearly with respect to the Y direction. Furthermore, a plurality of (2) additional patterns 34 are arranged relative to one dummy wiring 30a. The other configurations are substantially the same as those of the wiring substrate 10E (Modified Example 5) shown in Figure 29.

[0208] (Variation Example 9) Figure 33 shows the wiring substrate 10I of Modified Example 9. In Figure 33, each additional pattern 34 extends in a straight line and is inclined with respect to the X and Y directions, respectively. In this case, a plurality of (2) additional patterns 34 are arranged relative to one dummy wiring 30a. The other configurations are substantially the same as those of the wiring substrate 10H (Modified Example 8) shown in Figure 32.

[0209] (Variation Example 10) Figure 34 shows the wiring board 10J of Modified Example 10. In Figure 34, each additional pattern 34 has a cross shape when viewed from a planar perspective. In this case, one additional pattern 34 is arranged relative to one dummy wiring 30a. The other configurations are substantially the same as those of the wiring board 10E (Modified Example 5) shown in Figure 29.

[0210] (Variation Example 11) Figure 35 shows the wiring substrate 10K of Modified Example 11. In Figure 35, each additional pattern 34 has a dot shape when viewed from a planar perspective. In this case, a plurality of dot-shaped additional patterns 34 are arranged relative to one dummy wiring 30a, and the plurality of additional patterns 34 are arranged in both the X and Y directions. The other configurations are substantially the same as those of the wiring substrate 10G (Modified Example 7) shown in Figure 31.

[0211] (Variation Example 12) Figure 36 shows the wiring board 10L of Modified Example 12. In Figure 36, each additional pattern 34 has a cross shape when viewed from a planar perspective. In this case, one additional pattern 34 is arranged relative to one dummy wiring 30a. The other configurations are substantially the same as those of the wiring board 10H (Modified Example 8) shown in Figure 32.

[0212] (Variation Example 13) Figure 36 shows the wiring substrate 10M of Modified Example 13. In Figure 36, each additional pattern 34 has a dot shape when viewed from a planar perspective. In this case, a plurality of dot-shaped additional patterns 34 are arranged relative to one dummy wiring 30a, and the plurality of additional patterns 34 are arranged in rows along both the X and Y directions. The other configurations are substantially the same as those of the wiring substrate 10H (Modified Example 8) shown in Figure 32.

[0213] Furthermore, although not shown in the figure, additional patterns 34 can also be provided in the dummy pattern area 30 of the wiring substrates 10, 10A~10D shown in Figures 18 to 28.

[0214] <Third Implementation Form> Next, the third embodiment will be described with reference to Figures 38 to 51. Figures 38 to 51 are diagrams showing the third embodiment. In Figures 38 to 51, the same symbols are added to the parts that are the same as those in the second embodiment shown in Figures 18 to 37, and detailed descriptions are omitted.

[0215] [Structure of the wiring board] The configuration of the wiring board of this embodiment will be described with reference to Figures 38 to 42. Figures 38 to 42 are diagrams showing the wiring board of this embodiment.

[0216] As shown in FIG38, the wiring board 10 of this embodiment is disposed on a display, such as an image display device. This wiring board 10 includes: a substrate 11, which is transparent; and an antenna pattern region 20 disposed on the substrate 11. Furthermore, a power supply unit 40 is electrically connected to the antenna pattern region 20.

[0217] In this embodiment, the structure of the substrate 11 is roughly the same as that in the second embodiment.

[0218] Each antenna pattern region 20 is approximately rectangular from a planar perspective. Each antenna pattern region 20 is formed such that its long side is parallel to the Y-direction and its short side (width direction) is parallel to the X-direction. The length La of the long side (Y-direction) of each antenna pattern region 20 can be selected in the range of, for example, 3 mm or more and 100 mm or less, and the width Wa of the short side (width direction) of each antenna pattern region 20 can be selected in the range of, for example, 1 mm or more and 10 mm or less.

[0219] The antenna pattern area 20 is formed by forming metal wires into a grid shape or a mesh shape, and has repeating patterns in the X and Y directions. That is, the antenna pattern area 20 is composed of repeating L-shaped unit pattern shapes 20a (see Figure 40), wherein the aforementioned unit pattern shape 20a is composed of a portion extending in the X direction (a part of the antenna connection wiring 22 described later) and a portion extending in the Y direction (a part of the antenna wiring 21 described later).

[0220] As shown in Figure 39, each antenna pattern area 20 includes a plurality of antenna wirings 21 that function as antennas, and a plurality of antenna connection wirings 22 connecting the plurality of antenna wirings 21. Specifically, the plurality of antenna wirings 21 and the plurality of antenna connection wirings 22 are integrated as a whole and form a grid or mesh shape. Each antenna wiring 21 extends in a direction corresponding to the antenna's frequency band (long side direction, Y direction), and each antenna connection wiring 22 extends in a direction orthogonal to the antenna wirings 21 (width direction, X direction). The antenna wirings 21 function primarily as antennas by having a length La corresponding to a predetermined frequency band (the length of the aforementioned antenna pattern area 20, see Figure 38). On the other hand, the antenna connection wirings 22, by connecting these antenna wirings 21 to each other, suppress the following adverse conditions: antenna wirings 21 becoming disconnected, or antenna wirings 21 becoming disconnected from the power supply unit 40.

[0221] Each antenna pattern region 20 is surrounded by adjacent antenna wirings 21 and adjacent antenna connection wirings 22, forming a plurality of openings 23. Furthermore, each antenna pattern region 20 has a central portion 20c in the width direction (X direction) and a pair of edge portions 20e1 and 20e2 in the width direction (X direction). The central portion 20c in the width direction refers to the portion located at equal distances along the width direction from both ends of the antenna pattern region 20 at its width edges. Moreover, the central portion 20c and the edge portions 20e1 and 20e2 in the width direction may each have a certain width (length in the X direction). For example, the central portion 20c and the edge portions 20e1 and 20e2 may also be regions having a width (length in the X direction) of approximately 5% to 30% of the width Wa of the antenna pattern region 20.

[0222] As shown in Figures 40(a) and (b), a plurality of antenna wirings 21 are arranged at intervals (p1) along the width direction (X direction) of the antenna pattern region 20. In this case, the plurality of antenna wirings 21 are arranged at different intervals in the central portion 20c and the edge portions 20e1 and 20e2 of the width direction (X direction) of the antenna pattern region 20. That is, the plurality of antenna wirings 21 are arranged with a wider interval P1A in the central portion 20c of the width direction of the antenna pattern region 20, and with a narrower interval P1B (P1A>P1B) in the edge portions 20e1 and 20e2. Furthermore, the interval P1 of the plurality of antenna wirings 21 is the widest (p1A) in the central portion 20c of the width direction of the antenna pattern region 20, and the narrowest (p1B) in the edge portions 20e1 and 20e2. Specifically, the spacing P1A of the antenna wiring 21 in the central portion 20c of the antenna pattern area 20 in the width direction can be set to, for example, a range of 0.05 mm or more and 1 mm or less. The spacing P1B of the antenna wiring 21 in the edge portions 20e1 and 20e2 of the antenna pattern area 20 in the width direction can be set to, for example, a range of 0.01 mm or more and 0.3 mm or less.

[0223] The spacing P1 of the plurality of antenna wirings 21 can gradually change from the spacing P1B in the width-direction edge portions 20e1, 20e2 to the spacing P1A in the width-direction center portion 20c. Alternatively, the plurality of antenna wirings 21 can be arranged with a uniform spacing P1B in the region near the width-direction edge portions 20e1, 20e2, and with a uniform spacing P1A in the region near the width-direction center portion 20c. Furthermore, in this embodiment, the spacing P1B of the antenna wirings 21 in one width-direction edge portion 20e1 is equal to the spacing P1B of the antenna wirings 21 in the width-direction edge portion 20e2 on the other side. However, it is not limited to this, and the spacing P1B of the antenna wirings 21 in one width-direction edge portion 20e1 and the other width-direction edge portion 20e2 can also be different.

[0224] A plurality of antenna connection wirings 22 are arranged at equal intervals along the long side (Y direction) of the antenna pattern area 20. The spacing P2 of the plurality of antenna connection wirings 22 can be set to, for example, a range of 0.01 mm or more and 1 mm or less. Each opening 23 is formed into a generally rectangular or generally square shape in a planar view, and its area is larger than that of the opening 23 located on the side of the center portion 20c in the width direction compared to the opening 23 located on the edge portions 20e1 and 20e2 in the width direction. Furthermore, a transparent substrate 11 is exposed from each opening 23. Therefore, by setting the area of ​​each opening 23 to be larger, the transparency of the wiring substrate 10 as a whole can be improved. Moreover, although each antenna wiring 21 and each antenna connection wiring 22 are orthogonal to each other, they are not limited to this and can also intersect each other at acute or obtuse angles. Furthermore, although the spacing P2 of the antenna connection wiring 22 is uniform in the long side direction (Y direction) of the antenna pattern area 20, it is not limited to this and can also be set to be non-uniform in the long side direction (Y direction).

[0225] As shown in Figures 41 and 42, the cross-sectional shapes of each antenna wiring 21 and each antenna connecting wiring 22 are approximately the same as those in the second embodiment. Furthermore, the materials used for the antenna wiring 21 and the antenna connecting wiring 22 can also be the same as those used in the second embodiment.

[0226] Furthermore, in this embodiment, the central portion 20c of the antenna pattern region 20 in the width direction has a predetermined aperture ratio Ac, and the edge portions 20e1 and 20e2 of the antenna pattern region 20 in the width direction have predetermined aperture ratios Ae. Here, the aperture ratio Ac in the central portion 20c in the width direction can be set to, for example, a range of 87% or more and less than 100%. Also, the aperture ratio Ae in the edge portions 20e1 and 20e2 in the width direction can be set to, for example, a range of 85% or more and less than 99%. As described above, the plurality of antenna wirings 21 are arranged with a relatively wide spacing P1A in the central portion 20c of the antenna pattern region 20 in the width direction, and with a relatively narrow spacing P1B in the edge portions 20e1 and 20e2 in the width direction. Therefore, the aperture ratio Ac in the central portion 20c of the antenna pattern region 20 in the width direction becomes larger than the aperture ratio Ae in the edge portions 20e1 and 20e2 in the width direction (Ac>Ae). In this way, as will be described later, the current distribution in the antenna pattern region 20 can be made more uniform, and the antenna characteristics can be improved.

[0227] Furthermore, the difference (|Ac-Ae|) between the aperture ratio Ac in the central portion 20c of the antenna pattern region 20 in the width direction and the aperture ratio Ae in the edge portions 20e1 and 20e2 of the antenna pattern region 20 in the width direction should preferably be set to a range greater than 0% and less than 15%. In this way, by setting the difference between the aperture ratio Ac and the aperture ratio Ae to the above range, the antenna pattern region 20 can maintain its function as an antenna and make the current distribution in the antenna pattern region 20 more uniform.

[0228] Furthermore, the overall aperture ratio At of the antenna pattern region 20 can be set to, for example, a range of 87% or more and less than 100%. By setting the overall aperture ratio At of the wiring board 10 to this range, the conductivity and transparency of the wiring board 10 can be ensured.

[0229] Furthermore, the aperture ratio refers to the percentage (%) of the area occupied by the open area (the area where the metal parts of the antenna wiring 21, antenna connection wiring 22, etc. are absent and the substrate 11 is exposed) in a predetermined area (e.g., a part of the antenna pattern area 20).

[0230] Furthermore, the configuration of the power supply unit 40 is roughly the same as that of the second embodiment.

[0231] [Manufacturing Method of Wiring Board] Next, the manufacturing method of the wiring board of this embodiment will be described with reference to Figures 43(a)-(h). Figures 43(a)-(h) are cross-sectional views showing the manufacturing method of the wiring board of this embodiment.

[0232] First, as shown in FIG43(a), a substrate 11 is prepared, and a conductive layer 51 is formed over approximately the entire surface area of ​​this substrate 11. In this embodiment, the thickness of the conductive layer 51 is 200 nm. However, it is not limited to this, and the thickness of the conductive layer 51 can be appropriately selected in the range of 10 nm or more and 1000 nm or less. In this embodiment, the conductive layer 51 is formed using copper by sputtering. As a method for forming the conductive layer 51, plasma chemical vapor deposition (pCVD) can also be used.

[0233] Next, as shown in FIG43(b), a photocurable insulating resist 52 is supplied to approximately the entire surface area of ​​the substrate 11. Examples of this photocurable insulating resist 52 include organic resins such as epoxy resins.

[0234] Next, a transparent embossing mold 53 with protrusions 53a is prepared (Fig. 43(c)). This mold 53 is brought close to the substrate 11 so that the photocurable insulating resist 52 is spread between the mold 53 and the substrate 11. Then, by irradiating light from the mold 53 side, the photocurable insulating resist 52 is cured to form an insulating layer 54. Thereby, a groove 54a with the shape of the transferred protrusions 53a is formed on the surface of the insulating layer 54. The groove 54a has a planar shape pattern corresponding to the antenna wiring 21 and the antenna connection wiring 22.

[0235] Then, by peeling the mold 53 from the insulating layer 54, the insulating layer 54 with the cross-sectional structure shown in FIG43(d) is obtained. The direction in which the mold 53 is peeled from the insulating layer 54 should preferably be the Y direction of the extension of the longer antenna wiring 21.

[0236] Thus, the trench 54a can be formed on the surface of the insulating layer 54 by imprinting, and the shape of the trench 54a can be set to a finer shape. Furthermore, not limited to this, the insulating layer 54 can also be formed by photolithography. In this case, the resist pattern is formed by photolithography to expose the conductive layer 51 corresponding to the antenna wiring 21 and the antenna connection wiring 22.

[0237] As shown in Figure 43(d), there may be residual insulating material at the bottom of the trench 54a of the insulating layer 54. Therefore, the residual insulating material can be removed by wet treatment using permanganate solution or N-methyl-2-pyrrolidone, or by dry treatment using oxygen plasma. In this way, by removing the residual insulating material, the trench 54a exposing the conductive layer 51 can be formed as shown in Figure 43(e).

[0238] Next, as shown in FIG43(f), the trench 54a of the insulating layer 54 is filled with a conductor 55. In this embodiment, the conductive layer 51 is used as a seed layer, and the trench 54a of the insulating layer 54 is filled with copper using an electrolytic plating method.

[0239] Next, as shown in FIG43(g), the insulating layer 54 is removed. In this case, the insulating layer 54 on the substrate 11 can be removed by performing a wet treatment using a permanganate solution or N-methyl-2-pyrrolidone, or a dry treatment using oxygen plasma.

[0240] Next, as shown in FIG43(h), the conductive layer 51 on the surface of the substrate 11 is removed. At this time, the conductive layer 51 is etched to expose the surface of the substrate 11 by performing a wet process using an aqueous hydrogen peroxide solution. This process is repeated to obtain a wiring substrate 10, which has a substrate 11 and an antenna pattern region 20 disposed on the substrate 11. In this case, the antenna pattern region 20 includes antenna wiring 21 and antenna connection wiring 22. The conductor 55 includes antenna wiring 21 and antenna connection wiring 22. At this time, a power supply section 40 can also be formed by a portion of the conductor 55. Alternatively, a flat plate-shaped power supply section 40 can be prepared separately and electrically connected to the antenna pattern region 20.

[0241] [The function of this implementation] Next, the function of the wiring board formed by such a configuration will be explained.

[0242] As shown in Figure 44, the wiring board 10 is incorporated into the image display device 90, which has a display 91. The wiring board 10 is disposed on the display 91. Examples of such image display devices 90 include mobile terminal devices such as smartphones and tablet computers. The antenna pattern area 20 of the wiring board 10 is electrically connected to the wireless communication circuit 92 of the image display device 90 through the power supply unit 40. In this way, radio waves of a predetermined frequency can be transmitted and received through the antenna pattern area 20, and communication can be performed using the image display device 90.

[0243] However, generally speaking, during the transmission and reception of radio waves using the antenna pattern region 20, the current flowing in the antenna pattern region 20 does not become uniform in the width direction (X direction). Specifically, the current flowing in the width-direction edges 20e1 and 20e2 of the antenna pattern region 20 becomes larger than the current flowing in the width-direction center 20c of the antenna pattern region 20.

[0244] Figure 51 is a diagram showing the calculated current values ​​flowing in a uniform grid-like antenna pattern and a uniform plate-like antenna pattern, as a reference example. In Figure 51, the horizontal axis shows the position of the antenna pattern in the width direction; the left end of the horizontal axis is the edge of the antenna pattern in the width direction, and the right end is the center of the antenna pattern in the width direction. The vertical axis shows the current values ​​flowing in the antenna pattern. As can be clearly seen from Figure 51, when the antenna pattern is set to a uniform grid-like or uniform plate-like shape, the current value at the edge of the antenna pattern in the width direction is greater than that at the center of the antenna pattern in the width direction. In this case, because the current distribution in the antenna pattern does not become uniform, it is difficult to sufficiently improve the antenna characteristics.

[0245] In contrast, in this embodiment, the aperture ratio Ac in the central portion 20c of the antenna pattern region 20 in the width direction is set to be higher than the aperture ratio Ae in the edge portions 20e1 and 20e2 of the antenna pattern region 20 in the width direction (Ac>Ae). That is, the density (spacing P1A) of the antenna wiring 21 in the edge portions 20e1 and 20e2 in the width direction, where the current value is higher, is set to be higher than the density (spacing P1B) of the antenna wiring 21 in the central portion 20c in the width direction, where the current value is lower. Therefore, compared with the case where the antenna pattern grid is uniform, the antenna characteristics can be further improved because the current distribution can be uniformized in the central portion 20c and the edge portions 20e1 and 20e2 in the width direction of the antenna pattern region 20.

[0246] Furthermore, according to this embodiment, since the wiring board 10 has: a substrate 11 that is transparent; and an antenna pattern area 20 disposed on the substrate 11 and including a plurality of antenna wirings 21 that function as antennas, the transparency of the wiring board 10 can be ensured. Therefore, since the display 91 can be seen through the opening 23 of the antenna pattern area 20 when the wiring board 10 is disposed on the display 91, there is no obstruction to the visibility of the display 91.

[0247] Furthermore, according to this embodiment, the antenna pattern area 20 includes a plurality of antenna connection lines 22 connecting a plurality of antenna lines 21. This makes the antenna lines 21 less prone to breakage and suppresses any reduction in the antenna function of the antenna lines 21.

[0248] (Modified Example) Next, various modifications of the wiring board will be described with reference to Figures 45 to 50. Figures 45 to 50 show various modifications of the wiring board. The modifications shown in Figures 45 to 50 are modifications in which the configuration of the antenna pattern area 20 and / or the power supply section 40 is different; other configurations are substantially the same as the embodiments shown in Figures 38 to 44 above. In Figures 45 to 50, the same symbols are used for the parts that are the same as those shown in Figures 38 to 44, and detailed descriptions are omitted.

[0249] (Variation Example 1) Figure 45 shows the wiring substrate 10P of Modified Example 1. In Figure 45, a gap 61 is formed in the central portion 20c of the antenna pattern area 20 in the width direction. The gap 61 is formed into a roughly rectangular shape in a planar view, and its long side is parallel to the Y direction. The antenna wiring 21 and antenna connection wiring 22 are not provided in the gap 61, but the substrate 11 is exposed. The width Wb (length in the X direction) of this gap 61 can also be set to a range of approximately 20% to 80% of the width Wa of the antenna pattern area 20.

[0250] The antenna pattern region 20 has a first pattern region 20f and a second pattern region 20g separated by a gap 61. In the first pattern region 20f and the second pattern region 20g, the metal wires are formed into a grid shape or a mesh shape, respectively. The first pattern region 20f and the second pattern region 20g each include a plurality of antenna wirings 21 and a plurality of antenna connection wirings 22.

[0251] The two edges 20e1 and 20e2 in the width direction of the antenna pattern region 20 are respectively disposed in the first pattern region 20f and the second pattern region 20g. That is, the edge 20e1 in the width direction on the negative side of the X direction is disposed in the first pattern region 20f, and the edge 20e2 in the width direction on the positive side of the X direction is disposed in the second pattern region 20g. The width Wc (length in the X direction) of the first pattern region 20f and the second pattern region 20g can also be set to a range of approximately 10% to 40% of the width Wa of the antenna pattern region 20. Furthermore, in Figure 45, although the width Wc of the first pattern region 20f and the width Wc of the second pattern region 20g are equal, their equal widths can also be different.

[0252] Furthermore, the first pattern region 20f and the second pattern region 20g are electrically connected to each other via the central pattern region 20h. In the central pattern region 20h, the metal wires are formed into a grid shape or a mesh shape. The central pattern region 20h includes a plurality of antenna wirings 21 and a plurality of antenna connection wirings 22. The central pattern region 20h is located at the center 20c of the antenna pattern region 20 in the width direction. The width (length in the X direction) of the central pattern region 20h is equal to the width Wb of the gap 61. The length Lb in the Y direction of the central pattern region 20h can be selected, for example, in the range of 0.05 mm or more and 5.0 mm or less.

[0253] In Figure 45, the aperture ratio Ac in the central portion 20c of the antenna pattern region 20 in the width direction is formed to be larger than the aperture ratio Ae in the edge portions 20e1 and 20e2 in the width direction. That is, the spacing between antenna wirings 21 in the central portion 20c of the antenna pattern region 20 (central pattern region 20h) in the width direction is formed to be wider than the spacing between antenna wirings 21 in the edge portions 20e1 and 20e2 of the antenna pattern region 20 (first pattern region 20f and second pattern region 20g) in the width direction. This allows for uniform current distribution in the central portion 20c and the edge portions 20e1 and 20e2 of the antenna pattern region 20 in the width direction. Furthermore, the transparency of the wiring substrate 10 can be improved by forming a gap 61 in the central portion 20c of the antenna pattern region 20 in the width direction.

[0254] (Variation Example 2) Figure 46 shows the wiring substrate 10Q of Modified Example 2. The wiring substrate 10Q shown in Figure 46 has a dummy pattern region 30 formed in the gap 61 of the wiring substrate 10P shown in Figure 45 (Modified Example 1). This dummy pattern region 30 is disposed between the first pattern region 20f and the second pattern region 20g. The dummy pattern region 30 differs from the antenna pattern region 20 and does not actually function as an antenna.

[0255] The dummy pattern region 30 is composed of repetitions of dummy wirings 30a with predetermined unit pattern shapes. That is, the dummy pattern region 30 includes a plurality of dummy wirings 30a of the same shape, each dummy wiring 30a being electrically independent of the antenna pattern region 20 (antenna wiring 21 and antenna connection wiring 22). Furthermore, the plurality of dummy wirings 30a are regularly arranged covering the entire area within the dummy pattern region 30. The plurality of dummy wirings 30a are separated from each other in the planar direction and protrude from the substrate 11, arranged in an island-like shape. That is, each dummy wiring 30a is electrically independent of the antenna pattern region 20, the power supply section 40, and other dummy wirings 30a. Each dummy wiring 30a is approximately L-shaped in a planar view. Furthermore, the width (length in the X direction) of the dummy wiring 30a can also be matched with the spacing of the antenna wiring 21, gradually narrowing from the center of the width direction (X direction) of the dummy pattern area 30 toward the side edge of the width direction (X direction).

[0256] In this case, the dummy wiring 30a has a shape that lacks a portion of the unit pattern shape 20a of the antenna pattern region 20 (see Figure 40(a)). That is, the shape of the dummy wiring 30a is a shape that is the L-shaped unit pattern shape 20a of the antenna pattern region 20 with a portion removed. As a result, it becomes difficult to visually distinguish the difference between the antenna pattern region 20 and the dummy pattern region 30, and it becomes difficult to see the antenna pattern region 20 disposed on the substrate 11.

[0257] Thus, by providing a dummy pattern area 30 electrically independent of the antenna pattern area 20 in the gap 61, the boundary between the antenna pattern area 20 and the gap 61 becomes less clear. As a result, the antenna pattern area 20 is difficult to see on the front of the display 91, and it is difficult for the user of the image display device 90 to identify the antenna pattern area 20 with the naked eye.

[0258] (Variation Example 3) Figure 47 shows the wiring board 10R of Modified Example 3. In Figure 47, the length (length in the Y direction) Lc of the central portion 40c in the width direction of the power supply section 40 becomes longer than the length (length in the Y direction) Ld of each edge portion 40e1, 40e2 in the width direction of the power supply section 40. That is, the power supply section 40 is triangular in planar view, and the length (length in the Y direction) of the power supply section 40 gradually shortens from the central portion 40c in the width direction toward each edge portion 40e1, 40e2 in the width direction. The power supply section 40 has a straight long side 41a electrically connected to the antenna pattern area 20, and a pair of straight short sides 41b, 41c respectively connected to the long side 41a. Furthermore, the planar shape of the power supply section 40 is not limited to a triangular shape. For example, the short sides 41b, 41c can also be formed into a stepped shape or an arc shape.

[0259] Thus, by making the length Lc of the central portion 40c in the width direction of the power supply section 40 longer than the length Ld of the edge portions 40e1 and 40e2 in the width direction, the current can be more easily concentrated in the central portion 40c in the width direction of the power supply section 40. This makes the current distribution more uniform in the central portion 20c and the edge portions 20e1 and 20e2 in the width direction of the antenna pattern region 20, thereby improving antenna characteristics. Furthermore, by making the length Lc of the central portion 40c in the width direction of the power supply section 40, where the current is easily concentrated, longer, the heat generated by the power supply section 40 can be dispersed, suppressing the temperature rise of the power supply section 40. Moreover, since the overall area of ​​the power supply section 40 can be reduced, the wiring board 10 can be made lighter.

[0260] (Variation Example 4) Figure 48 shows the wiring substrate 10S of Modified Example 4. In Figure 48, a gap 61 is formed in the central portion 20c of the antenna pattern region 20 in the width direction, where neither the antenna wiring 21 nor the antenna connecting wiring 22 is provided. Furthermore, the antenna pattern region 20 has a first pattern region 20f and a second pattern region 20g separated by the gap 61. The configuration of this antenna pattern region 20 is substantially the same as that of the antenna pattern region 20 of the wiring substrate 10P shown in Figure 45 (Modified Example 1).

[0261] Furthermore, the power supply section 40 is triangular in shape, and the length (length in the Y direction) of the central portion 40c in the width direction of the power supply section 40 is longer than the length (length in the Y direction) of each edge portion 40e1, 40e2 in the width direction of the power supply section 40. The configuration of this power supply section 40 is substantially the same as that of the power supply section 40 of the wiring board 10R shown in FIG47 (Modified Example 3).

[0262] In this case, the transparency of the wiring substrate 10 can be improved, and the current distribution in the antenna pattern area 20 can be made more uniform.

[0263] (Variation Example 5) Figure 49 shows the wiring substrate 10T of Modified Example 5. In Figure 49, connecting pattern regions 20m and 20n are respectively provided between the central pattern region 20h, the first pattern region 20f, and the second pattern region 20g of the antenna pattern region 20. One connecting pattern region 20m is provided between the central pattern region 20h and the first pattern region 20f, and the other connecting pattern region 20n is provided between the central pattern region 20h and the second pattern region 20g. The connecting pattern regions 20m and 20n are approximately triangular in shape from a planar perspective, and have inclined portions 20p and 20q that are formed obliquely relative to the width direction (X direction) of the antenna pattern region 20. Although the inclined portions 20p and 20q extend in a straight line, they are not limited to this and can also extend in a curved or stepped shape. Furthermore, the connecting pattern areas 20m and 20n, like the central pattern area 20h and the second pattern area 20g, include antenna wiring 21 and antenna connection wiring 22 formed in a grid or mesh shape. Apart from this, the configuration is substantially the same as that of the wiring substrate 10S shown in FIG48 (Modified Example 4).

[0264] In this case, the transparency of the wiring substrate 10 can be improved, and the current distribution in the antenna pattern area 20 can be made more uniform.

[0265] (Variation Example 6) Figure 50 shows the wiring board 10U of Modified Example 6. In Figure 50, each antenna pattern area 20 includes a plurality of antenna wirings 21 that function as antennas, and a plurality of antenna connection wirings 22 connecting the plurality of antenna wirings 21. In this case, the plurality of antenna wirings 21 are arranged at equal intervals. Also, the plurality of antenna connection wirings 22 are arranged at equal intervals. Furthermore, the configuration of the power supply section 40 is substantially the same as that of the power supply section 40 of the wiring board 10R shown in Figure 47 (Modified Example 3).

[0266] In this way, by arranging the plurality of antenna wirings 21 and the plurality of antenna connecting wirings 22 at equal intervals, the size of the openings 23 in each antenna pattern area 20 will not be inconsistent, making the antenna pattern area 20 difficult to see with the naked eye. Furthermore, the current distribution in the antenna pattern area 20 can be made more uniform.

[0267] The plurality of constituent elements disclosed in the above embodiments and variations may be appropriately combined as needed. Alternatively, several constituent elements may be deleted from all the constituent elements shown in the above embodiments and variations.

[0268] 10, 10a, 10b, 10c, 10d, 10e, 10f, 10g, 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, 10I, 10J, 10K, 10L, 10M, 10P, 10Q, 10R, 10S, 10T, 10U: Wiring board 11,100,100a,100b,100c,100d,100e,100f,100g:Substrate 20: Antenna pattern area (wiring pattern area) 20A: Wireless Communication Module 20a: Unit pattern shape 20c, 40c: Central part in the width direction 20e1, 20e2, 40e1, 40e2: Edge portion in the width direction 20f: Pattern Area 1 20g: Pattern 2 area 20h: Central pattern area 20m, 20n: Connecting pattern areas 20p, 20q: Inclined section 21: Antenna wiring 22: Antenna connection wiring 23: Opening 30: Virtual pattern area 30a: Dummy Wiring 31, 31a, 31b, 31c: First dummy wiring section 32, 32c: Second dummy wiring section 33a, 33b, 33c, 33d, 33e, 33f, 33g, 61: Voids 34: Additional Patterns 40: Power Supply Department 41a: Long side 41b, 41c: Short side 51,400: Conductive layer 52: Light-curing insulating agent 53: Mold 53a,d:convex part 54,500: Insulation layer 54a: Ditch 55: Conductor 90: Image display device 91: Monitor 92: Wireless communication circuit 102: Side 1 104: Second side 106g: Wiring area 200, 200a, 200b, 200c, 200d, 200e, 200f, 200g: Wiring 1 201, 201a, 201b, 201c, 201d, 201e, 201f, 303, 303a, 303b, 303c, 303d, 303e, 303f: Back 202, 202a, 202b, 202c, 202d, 202e, 202f, 304, 304a, 304b, 304c, 304d, 304e, 304f: Front 209,209a,209b,209c,209d,209f,210,210a,210b,210c,210d,210e,210f,305,305a,305b,305c,305d,306,306a,306b,306c,306d,306e,306f: Side view 300, 300a, 300b, 300c, 300d, 300e, 300f, 300g: Wiring 2 307b, 307c, 307d, 308c, 308d, 211c, 211d, 212c, 212d: Upper and lateral sides 410: First conductor 420: Second conductor 510: First Ditch 520: Second Ditch 600: Modular 700g: Circuit D1, D2, D3, X, Y, Z: Direction e,f: curved surfaces G1, G2: Interval H1, H2, H3, H4: Height L1, L2, L3, L4, L5, La, Lb, Lc, Ld: Length P1, P1A, P1B, P2: Spacing T1: Thickness W1, W2, W3, W4: Line width Wa, Wb, Wc: Width

Claims

1. A wiring substrate comprising: a substrate having transparency; and an antenna pattern region disposed on the substrate and including a plurality of antenna wirings having the function of an antenna, wherein the aperture ratio of the central portion of the antenna pattern region in the width direction is higher than the aperture ratio of the edge portion of the antenna pattern region in the width direction.

2. The wiring substrate of claim 1, wherein the spacing between the plurality of antenna wirings in the central portion of the aforementioned antenna pattern area in the width direction is wider than the spacing between the plurality of antenna wirings in the edge portion of the aforementioned antenna pattern area in the width direction.

3. The wiring substrate of claim 1, wherein a gap is formed in the central part of the aforementioned antenna pattern area in the width direction, where no aforementioned antenna wiring is provided.

4. The wiring substrate of claim 3, wherein a dummy pattern area is formed in the aforementioned gap, the aforementioned dummy pattern area comprising a plurality of dummy wirings electrically independent of the aforementioned antenna wirings.

5. The wiring substrate of claim 3, wherein the aforementioned antenna pattern area has a first pattern area and a second pattern area separated by the aforementioned gap, the aforementioned first pattern area and the second pattern area are respectively disposed on the two edges of the aforementioned antenna pattern area in the width direction, and the aforementioned first pattern area and the second pattern area are electrically connected to each other by a central pattern area.

6. The wiring board of claim 5, wherein a connecting pattern area is provided between the aforementioned central pattern area and the aforementioned first pattern area and second pattern area, wherein the aforementioned connecting pattern area has an inclined portion formed obliquely relative to the width direction of the aforementioned antenna pattern area.

7. The wiring board of any one of claims 1 to 6, wherein the aforementioned antenna pattern area is electrically connected to the power supply section, and the length of the aforementioned central portion in the width direction of the aforementioned power supply section is longer than the length of the aforementioned edge portion in the width direction of the aforementioned power supply section.

8. A wiring substrate comprising: a substrate having transparency; an antenna pattern region disposed on the substrate and including a plurality of antenna wirings having the function of an antenna; and a power supply section electrically connected to the antenna pattern region, wherein the length of the central portion of the power supply section in the width direction is longer than the length of the edge portion in the width direction of the power supply section.

9. A method for manufacturing a wiring substrate, comprising the following steps: preparing a transparent substrate; and forming an antenna pattern region on the substrate, wherein the antenna pattern region includes a plurality of antenna wirings that function as antennas, and the aperture ratio of the central portion of the antenna pattern region in the width direction is higher than the aperture ratio of the edge portion in the width direction of the antenna pattern region.

10. A method for manufacturing a wiring substrate, comprising the steps of: preparing a transparent substrate; and forming an antenna pattern area and a power supply portion on the substrate, wherein the antenna pattern area includes a plurality of antenna wirings that function as antennas, the power supply portion is electrically connected to the antenna pattern area, and the length of the power supply portion in the central portion in the width direction is longer than the length of the power supply portion in the edge portion in the width direction.

Citation Information

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