Wiring circuit board

Abstract

To provide a wiring circuit board that can reduce electrical resistance. [Solution] The wiring circuit board 1 comprises a metal support layer 11, a conductor layer 12, an insulating layer 13, and a circuit pattern arranged in order toward one side in the thickness direction. The circuit pattern comprises a first circuit pattern 14 having wiring 141 and a second circuit pattern 15 that is electrically connected to the conductor layer 12 and independent of the first circuit pattern 14. The wiring circuit board 1 also comprises a wiring section 2 on which the wiring 141 is arranged. In the wiring section 2, the length in the width direction perpendicular to the thickness direction of the conductor layer 12 and the direction in which the wiring 141 extends is longer than the length in the width direction of at least a portion of the thickness direction of the metal support layer 11.

Description

Technical Field

[0001] The present invention relates to a wiring circuit board.

Background Art

[0002] Conventionally, a wiring circuit board including a metal support layer, an insulating layer, and wiring in this order toward one side in the thickness direction is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003] :

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, in a wiring circuit board, further reduction of electrical resistance is required.

[0005] An object of the present invention is to provide a wiring circuit board capable of reducing electrical resistance.

Means for Solving the Problems

[0006] The present invention [1] is a wiring circuit board including a metal support layer, a conductor layer, an insulating layer, and a circuit pattern in this order toward one side in the thickness direction, wherein the circuit pattern includes a first circuit pattern having wiring and a second circuit pattern connected to the conductor layer and independent of the first circuit pattern, the wiring circuit board includes a wiring portion where the wiring is disposed, and in the wiring portion, a length in the width direction orthogonal to the thickness direction of the conductor layer and the extending direction of the wiring is longer than a length in at least a part of the width direction in the thickness direction of the metal support layer.

[0007] The present invention [2] includes the wiring circuit board described in [1] above, wherein in the wiring portion, the length in the width direction of the conductor layer is longer than the length in the width direction of the central part in the thickness direction of the metal support layer.

[0008] The present invention [3] includes a wiring circuit board as described in [1] or [2] above, wherein in the wiring portion, the length in the width direction of one end and the other end of the metal support layer in the thickness direction is longer than the length in the width direction of the central part of the metal support layer in the thickness direction.

[0009] The present invention [4] includes a wiring circuit board according to [1] or [2] above, wherein the metal support layer in the wiring portion has a substantially tapered shape in cross-section, widening in the width direction from one side to the other in the thickness direction.

[0010] The present invention [5] includes a wiring circuit board according to any one of the above [1] to [4], wherein the insulating layer is provided with through holes, and the second circuit pattern is electrically connected to the conductor layer through the through holes.

[0011] The present invention [6] is a wiring circuit board according to [5], wherein the first circuit pattern has a first terminal connected to the wiring, the second circuit pattern has a second terminal, the wiring circuit board further comprises a terminal arrangement portion on which the first terminal and the second terminal are arranged, and in the terminal arrangement portion, the insulating layer has the through hole, and the second terminal is arranged in the through hole.

[0012] The present invention [7] includes a wiring circuit board according to any one of the above [1] to [6], wherein in the wiring portion, the ratio of the widthwise length of the conductor layer to the minimum widthwise length of the metal support layer is 1.2 or more.

[0013] The present invention [8] includes a wiring circuit board according to any one of the above [1] to [7], wherein in the wiring portion, the ratio of the length in the width direction of the conductor layer to the length in the width direction of the central part in the thickness direction of the metal support layer is 1.2 or more.

[0014] The present invention [9] includes a wiring circuit board according to any one of the above [1] to [8], wherein the ratio of the thickness of the conductor layer to the thickness of the metal support layer is 0.003 or more. [Effects of the Invention]

[0015] In the wiring circuit board of the present invention, the length in the width direction perpendicular to the thickness direction of the conductor layer and the direction in which the wiring extends is longer than the length in the width direction of at least a portion of the thickness direction of the metal support layer. Therefore, electrical resistance can be reduced. [Brief explanation of the drawing]

[0016] [Figure 1] Figure 1 shows a plan view of a wiring circuit board as one embodiment of the present invention. [Figure 2] Figure 2 is a cross-sectional view AA of the wiring circuit board shown in Figure 1. [Figure 3] Figure 3 is a cross-sectional view of the circuit board (BB) of the wiring circuit board shown in Figure 1. [Figure 4] Figures 4A to 4C are process diagrams illustrating the manufacturing method of the wiring circuit board shown in Figure 3. Figure 4A shows the conductor layer formation process, Figure 4B shows the insulating layer formation process, and Figure 4C shows the circuit pattern formation process. [Figure 5] Figures 5A and 5B are process diagrams illustrating the manufacturing method of the wiring circuit board shown in Figure 3, following Figures 4A to 4C. Figure 5A shows the cover insulating layer formation process, and Figure 4B shows the etching process. [Figure 6] Figure 6 shows a cross-sectional view of a first modified example of the wiring circuit board of the present invention. [Figure 7] Figure 7 shows a cross-sectional view of a second modified example of the wiring circuit board of the present invention. [Figure 8] Figure 8 shows a cross-sectional view of a third modified example of the wiring circuit board of the present invention. [Figure 9] Figure 9 shows a cross-sectional view of a fourth modified example of the wiring circuit board of the present invention. [Figure 10] Figure 10 shows a cross-sectional view of a fifth modified example of the wiring circuit board of the present invention. [Figure 11] Figure 11 shows a cross-sectional view of a sixth modified example of the wiring circuit board of the present invention. [Modes for carrying out the invention]

[0017] 1. Wiring circuit board An embodiment of the wiring circuit board 1 will be described with reference to Figures 1 to 3.

[0018] The wiring circuit board 1 includes a wiring section 2 on which the wiring 141 is arranged. Preferably, the wiring circuit board 1 further includes a plurality of terminal arrangement sections 3 on which the first terminal 142 and the second terminal 151 are arranged. Specifically, as shown in Figure 1, the wiring circuit board 1 includes a plurality of wiring sections 2 on which the wiring 141 is arranged, a terminal arrangement section 3A on one side of the wiring section 2 in the first direction on which the first terminal 142A and the second terminal 151A are arranged, and a terminal arrangement section 3B on the other side of the wiring section 2 in the first direction on which the first terminal 142B and the second terminal 151B are arranged.

[0019] The first direction is the direction in which the wiring 141 extends, as will be described later. The first direction (the direction in which the wiring 141 extends) is perpendicular to the thickness direction of the wiring circuit board 1. The second direction is the width direction of the wiring 141. The second direction (width direction) is perpendicular to both the thickness direction and the first direction.

[0020] The wiring circuit board 1 comprises multiple wiring sections 2. The wiring circuit board 1 shown in Figure 1 comprises three wiring sections 2. Wires 141 of the first circuit pattern 14, which will be described later, are arranged in the wiring sections 2. In other words, the wiring sections 2 have the wires 141 of the first circuit pattern 14, which will be described later. Furthermore, one wire 141 may be arranged in one wiring section 2, or multiple wires 141 may be arranged in one wiring section 2.

[0021] Each of the multiple wiring sections 2 is positioned between terminal arrangement section 3A and terminal arrangement section 3B in the first direction. In this embodiment, each of the multiple wiring sections 2 extends in the first direction. One end of each of the multiple wiring sections 2 in the first direction is continuous with terminal arrangement section 3A. The other end of each of the multiple wiring sections 2 in the first direction is continuous with terminal arrangement section 3B. In other words, terminal arrangement section 3B, wiring section 2, and terminal arrangement section 3A are continuous toward one side in the first direction. Note that the plan view shape of each of the multiple wiring sections 2 is not limited and may be straight or curved.

[0022] Multiple wiring sections 2 are arranged along the second direction (width direction). Multiple wiring sections 2 are spaced apart from each other in the second direction (width direction).

[0023] The widthwise length of the wiring section 2 is, for example, 10 μm to 300 μm, preferably 50 μm to 250 μm. Note that the widthwise length of the wiring section 2 is the maximum length in the second direction.

[0024] In the second direction, the spacing between adjacent wiring sections 2 is, for example, 5 μm to 300 μm, preferably 10 μm to 250 μm. The spacing between adjacent wiring sections 2 may be the same or different.

[0025] In the second direction, the ratio of the distance between adjacent wiring sections 2 to the widthwise length of the wiring section 2 (distance between adjacent wiring sections 2 / widthwise length of the wiring section 2) is, for example, 0.5 or more, preferably 1.0 or more, and for example, 5.0 or less, preferably 4.0 or less.

[0026] The terminal arrangement section 3A is configured to accommodate the first terminal 142A of the first circuit pattern 14 and the second terminal 151A of the second circuit pattern 15, as described later. In other words, the terminal arrangement section 3A has the first terminal 142A of the first circuit pattern 14 and the second terminal 151A of the second circuit pattern 15, as described later. The terminal arrangement section 3B is configured to accommodate the first terminal 142B of the first circuit pattern 14 and the second terminal 151B of the second circuit pattern 15, as described later. In other words, the terminal arrangement section 3B has the first terminal 142B of the first circuit pattern 14 and the second terminal 151B of the second circuit pattern 15, as described later.

[0027] The terminal arrangement sections 3A and 3B are spaced apart from each other in the first direction. Each of the terminal arrangement sections 3A and 3B extends in the second direction.

[0028] As shown in Figures 2 and 3, the wiring circuit board 1 comprises a metal support layer 11, a conductor layer 12, an insulating layer 13, and a circuit pattern arranged in order toward one side in the thickness direction.

[0029] More specifically, as shown in Figures 2 and 3, the wiring section 2 comprises a metal support layer 11, a conductor layer 12 disposed on one side of the metal support layer 11 in the thickness direction, an insulating layer 13 (base insulating layer) disposed on one side of the conductor layer 12 in the thickness direction, and wiring 141 of the first circuit pattern 14 disposed on one side of the insulating layer 13 in the thickness direction. The wiring section 2 may further include a cover insulating layer 16 as needed.

[0030] Furthermore, as shown in Figure 2, the terminal arrangement sections 3A and 3B include a metal support layer 11, a conductor layer 12 disposed on one side of the metal support layer 11 in the thickness direction, an insulating layer 13 disposed on one side of the conductor layer 12 in the thickness direction and having through holes 131, a first terminal 142 of a first circuit pattern 14 disposed on one side of the insulating layer 13 in the thickness direction and connected to wiring 141, and a second terminal 151 of a second circuit pattern 15 disposed in the through holes 131 of the insulating layer 13 and connected to the conductor layer 12.

[0031] (1) Metal support layer The metal support layer 11 is placed in the wiring section 2 and the terminal placement sections 3A and 3B. In other words, the wiring section 2 and the terminal placement sections 3A and 3B have the metal support layer 11. The metal support layer 11 is continuous in the wiring section 2 and the terminal placement sections 3A and 3B.

[0032] The metal support layer 11 is made of metal. Examples of materials for the metal support layer 11 include copper, nickel, cobalt, titanium, iron, and alloys thereof. Examples of alloys include copper alloys and stainless steel. Preferably, copper alloys are used as the material for the metal support layer 11.

[0033] The thickness of the metal support layer is, for example, 10 μm to 300 μm, preferably 50 μm to 250 μm. The thickness of the metal support layer is, for example, 10 μm or more, preferably 50 μm or more, and also, for example, 300 μm or less, preferably 250 μm or less.

[0034] The metal support layer 11 supports the conductor layer 12, the insulating layer 13, the circuit patterns (first circuit pattern 14 and second circuit pattern 15), and the cover insulating layer 16. More specifically, in the wiring section 2, the metal support layer 11 supports the wiring 141 of the first circuit pattern 14. In the terminal arrangement section 3A, the metal support layer 11 supports the first terminal 142A of the first circuit pattern 14 and the second terminal 151A of the second circuit pattern 15. In the terminal arrangement section 3B, the metal support layer 11 supports the first terminal 142B of the first circuit pattern 14 and the second terminal 151B of the second circuit pattern 15.

[0035] In the wiring section 2, the metal support layer 11 extends in a first direction along the wiring 141. In the wiring section 2, the metal support layers 11 are arranged along a second direction. In the wiring section 2, the metal support layers 11 are spaced apart from each other in the second direction. In the wiring section 2, the shape (cross-sectional shape) of the metal support layer 11 as viewed from the first direction is not particularly limited. In this embodiment, the cross-sectional shape of the metal support layer 11 in the wiring section 2 is substantially rectangular.

[0036] In the wiring section 2, the length of the metal support layer 11 in the width direction may be the same or different in the thickness direction. In this embodiment, in the wiring section 2, the length of the metal support layer 11 in the width direction is substantially the same in the thickness direction.

[0037] In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max For example, the thickness is 5 μm to 300 μm, preferably 10 μm to 250 μm, and more preferably 15 μm to 200 μm. In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max For example, the thickness is 5 μm or more, preferably 10 μm or more, more preferably 15 μm or more, and for example, 300 μm or more, preferably 250 μm or more, more preferably 200 μm or more. Note that in the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max This is the maximum widthwise length of the metal support layer 11 from one side to the other in the thickness direction of the metal support layer 11.

[0038] In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max However, if it is above the lower limit value mentioned above, the wiring 141 can be supported. Also, in the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max However, if it is below the above upper limit, the wiring circuit board 1 can be miniaturized. In other words, the wiring circuit board 1 is required to be miniaturized, and in the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max It is preferable that this value is below the upper limit mentioned above.

[0039] In the wiring section 2, the minimum widthwise length W11 of the metal support layer 11 min For example, the width of the metal support layer 11 is 1 μm to 250 μm, preferably 5 μm to 200 μm, and more preferably 10 μm to 150 μm. minis, for example, 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more, and, for example, 250 μm or more, preferably 200 μm or more, more preferably 150 μm or more. In the wiring portion 2, the minimum width direction length W11 of the metal support layer 11 min is the minimum width direction length of the metal support layer 11 from one side to the other side in the thickness direction of the metal support layer 11.

[0040] In the wiring portion 2, the minimum width direction length W11 of the metal support layer 11 min if it is equal to or greater than the above lower limit value, the wiring 141 can be supported. Also, in the wiring portion 2, the minimum width direction length W11 of the metal support layer 11 min if it is equal to or less than the above upper limit value, the wiring circuit board 1 can be miniaturized.

[0041] In the wiring portion 2, the width direction length W11 at the central portion in the thickness direction of the metal support layer 11 C is, for example, 1 μm to 250 μm, preferably 5 μm to 200 μm, more preferably 10 μm to 150 μm. In the wiring portion 2, the width direction length W11 at the central portion in the thickness direction of the metal support layer 11 C is, for example, 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more, and, for example, 250 μm or more, preferably 200 μm or more, more preferably 150 μm or more.

[0042] In the wiring portion 2, the width direction length W11 at the central portion in the thickness direction of the metal support layer 11 C if it is equal to or greater than the above lower limit value, the wiring 141 can be supported. Also, in the wiring portion 2, the width direction length W11 at the central portion in the thickness direction of the metal support layer 11 C if it is equal to or less than the above upper limit value, the wiring circuit board 1 can be miniaturized.

[0043] In the wiring portion 2, the width direction length W11 at the central portion in the thickness direction of the metal support layer 11 C may be the same as the maximum width direction length W11 of the metal support layer 11, and the minimum width direction length W11 of the metal support layer 11 max min ​It may be the same as the following. In the wiring section 2, the length W11 in the width direction of the center of the metal support layer 11 in the thickness direction C Preferably, the minimum widthwise length W11 of the metal support layer 11 min It is the same as above. In this embodiment, in the wiring section 2, the length of the metal support layer 11 in the width direction is substantially the same across the thickness direction, so W11 max =W11 min =W11 C That is the case.

[0044] Furthermore, in the wiring section 2 from one side in the thickness direction to the other side, the maximum widthwise length W11 of the metal support layer 11 max The width of the wiring section 2 may be the same as or different from the width of the wiring section 2.

[0045] In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max The ratio of the thickness of the metal support layer 11 to (thickness / W11) max ) is, for example, 2 or more, preferably 5 or more, and for example, 30 or less, preferably 10 or less. Hereinafter, in the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max The ratio of the thickness of the metal support layer 11 to (thickness / W11) max ) is defined as the aspect ratio of the metal support layer 11 in the wiring section 2.

[0046] If the aspect ratio of the metal support layer 11 in the wiring section 2 is greater than or equal to the above lower limit, the wiring section 2 can be easily deformed in the width direction compared to the thickness direction. In addition, the rigidity of the wiring section 2 in the thickness direction can be ensured.

[0047] The length in the width direction of each metal support layer 11 in each wiring section 2 (W11 max W11 min W11 C The aspect ratio and width may be adjusted as appropriate within the above range and may be the same or different.

[0048] (2) Conductor layer As shown in Figure 2, the conductor layer 12 is placed in the wiring section 2 and the terminal placement sections 3A and 3B. In other words, the wiring section 2 and the terminal placement sections 3A and 3B have the conductor layer 12.

[0049] Furthermore, as shown in Figures 2 and 3, the conductor layer 12 is positioned on one side in the thickness direction of the metal support layer 11. In other words, the conductor layer 12 is in contact with one side in the thickness direction of the metal support layer 11. The conductor layer 12 may preferably include a bonding layer (not shown) that joins the metal support layer 11 and the conductor layer 12. The bonding layer is made of metal. The bonding layer is, for example, a sputtering layer. Examples of materials for the bonding layer include chromium, nickel, titanium, and alloys thereof. The conductor layer 12 typically does not have a pattern.

[0050] The conductivity of the conductor layer 12 is higher than that of the metal support layer 11. Therefore, by forming the wiring 141 on one side in the thickness direction of the conductor layer 12, the transmission loss of the wiring 141 can be reduced. Examples of materials for the conductor layer 12 include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. The conductor layer 12 is preferably made of copper. The conductor layer 12 is a plated layer. Therefore, the thickness of the conductor layer 12 can be easily adjusted.

[0051] The thickness of the conductive layer 12 is, for example, 0.1 μm or more, preferably 0.5 μm or more, more preferably 1 μm or more, even more preferably 2 μm or more, and also, for example, 30 μm or less, preferably 20 μm or less, more preferably 15 μm or less, and even more preferably 10 μm or less.

[0052] If the thickness of the conductor layer 12 is greater than or equal to the lower limit value, the conductivity of the conductor layer 12 can be ensured in the thickness direction. In other words, electrical resistance can be reduced by making the second terminal 151A and the second terminal 151B conductive. If the thickness of the conductor layer 12 is less than or equal to the upper limit value, the flexibility of the wiring section 2 can be ensured in the thickness direction.

[0053] The ratio of the thickness of the conductor layer 12 to the thickness of the metal support layer 11 (thickness of conductor layer 12 / thickness of metal support layer 11) is, for example, 0.001 or more, preferably 0.003 or more, more preferably 0.005 or more, even more preferably 0.01 or more, and also, for example, 0.5 or less, preferably 0.3 or less, more preferably 0.1 or less, and even more preferably 0.08 or less.

[0054] If the ratio of the thickness of the conductor layer 12 to the thickness of the metal support layer 11 is greater than or equal to the lower limit, the conductivity of the conductor layer 12 can be ensured. In other words, electrical resistance can be reduced by making the second terminal 151A and the second terminal 151B electrically conductive. If the ratio of the thickness of the conductor layer 12 to the thickness of the metal support layer 11 is less than or equal to the upper limit, the elasticity of the wiring section 2 in the thickness direction can be adjusted.

[0055] In the wiring section 2, the conductor layer 12 typically covers the entire surface of one side in the thickness direction of the metal support layer 11. In the terminal arrangement section 3, the conductor layer 12 may cover the entire surface of one side in the thickness direction of the metal support layer 11, or it may cover one side in the thickness direction of the metal support layer 11, excluding the outer peripheral edge of the metal support layer 11.

[0056] In the wiring section 2, the widthwise length W12 of the conductor layer 12 is, for example, 5 μm to 300 μm, preferably 10 μm to 250 μm, and more preferably 15 μm to 200 μm. In the wiring section 2, the widthwise length W12 of the conductor layer 12 is, for example, 5 μm or more, preferably 10 μm or more, more preferably 15 μm or more, and also, for example, 300 μm or more, preferably 250 μm or more, and more preferably 200 μm or more.

[0057] In the wiring section 2, the widthwise length W12 of the conductor layer 12 is equal to the minimum widthwise length W11 of the metal support layer 11. min It is longer. In other words, in the wiring section 2, the length W12 in the width direction of the conductor layer 12 is longer than the length in the width direction of at least a portion of the thickness direction of the metal support layer 11.

[0058] In the wiring section 2, the minimum widthwise length W11 of the metal support layer 11min The ratio of the length W12 in the width direction of the conductor layer 12 to (W12 / W11 min ) is, for example, 1.0 to 5.0, preferably 1.1 to 5.0, more preferably 1.2 to 4.0, even more preferably 1.3 to 4.0, particularly preferably 1.4 to 3.0, and most preferably 1.5 to 3.0. In the wiring section 2, the minimum widthwise length W11 of the metal support layer 11 min The ratio of the length W12 in the width direction of the conductor layer 12 to (W12 / W11 min For example, the value is greater than 1.0, preferably 1.1 or higher, more preferably 1.2 or higher, even more preferably 1.3 or higher, particularly preferably 1.4 or higher, most preferably 1.5 or higher, and also, for example, 5.0 or lower, preferably 4.0 or lower, more preferably 3.0 or lower.

[0059] Furthermore, in the wiring section 2, the widthwise length W12 of the conductor layer 12 is preferably the widthwise length W11 of the central part in the thickness direction of the metal support layer 11. C Longer.

[0060] In the wiring section 2, the length W11 in the width direction of the center of the metal support layer 11 in the thickness direction C The ratio of the length W12 in the width direction of the conductor layer 12 to (W12 / W11 C ) is, for example, 1.0 to 5.0, preferably 1.1 to 5.0, more preferably 1.2 to 4.0, even more preferably 1.3 to 4.0, particularly preferably 1.4 to 3.0, and most preferably 1.5 to 3.0. In the wiring section 2, the widthwise length W11 of the central part in the thickness direction of the metal support layer 11 C The ratio of the length W12 in the width direction of the conductor layer 12 to (W12 / W11 C For example, the value is greater than 1.0, preferably 1.1 or higher, more preferably 1.2 or higher, even more preferably 1.3 or higher, particularly preferably 1.4 or higher, most preferably 1.5 or higher, and also, for example, 5.0 or lower, preferably 4.0 or lower, more preferably 3.0 or lower.

[0061] Furthermore, in the wiring section 2, the widthwise length W12 of the conductor layer 12 is equal to the maximum widthwise length W11 of the metal support layer 11. max It may be longer, the maximum widthwise length W11 of the metal support layer 11 max It may be shorter, the maximum widthwise length W11 of the metal support layer 11 max It may be the same as the above. In this embodiment, in the wiring section 2, the widthwise length W12 of the conductor layer 12 is the maximum widthwise length W11 of the metal support layer 11. max Longer.

[0062] In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max The ratio of the length W12 in the width direction of the conductor layer 12 to (W12 / W11 max ) is, for example, 1.0 to 4.0, preferably 1.2 to 4.0, and more preferably 1.5 to 3.0. In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max The ratio of the length W12 in the width direction of the conductor layer 12 to (W12 / W11 max For example, the value is 1.0 or higher, preferably 1.3 or higher, more preferably 1.5 or higher, and also, for example, 4.0 or lower, preferably 3.5 or lower, more preferably 3.0 or lower.

[0063] (3) Insulating layer As shown in Figures 2 and 3, the insulating layer 13 (base insulating layer) is placed in the wiring section 2 and the terminal placement sections 3A and 3B. In other words, the wiring section 2 and the terminal placement sections 3A and 3B have the insulating layer 13.

[0064] As shown in Figures 2 and 3, the insulating layer 13 (base insulating layer) is arranged on one side in the thickness direction of the conductor layer 12.

[0065] In the wiring section 2, the insulating layer 13 is placed between the conductor layer 12 and the wiring 141. The insulating layer 13 insulates the conductor layer 12 from the wiring 141. In the terminal arrangement sections 3A and 3B, the insulating layer 13 is placed between the conductor layer 12 and the first terminals 142A and 142B. The insulating layer 13 insulates the conductor layer 12 from the first terminals 142A and 142B. In other words, the insulating layer 13 is placed between the conductor layer 12 and the first circuit pattern 14, insulating the conductor layer 12 from the first circuit pattern 14. If there are areas in the terminal arrangement sections 3A and 3B where the conductor layer 12 is not placed, the insulating layer 13 may be placed on one side in the thickness direction of the metal support layer 11.

[0066] Furthermore, in this embodiment, the insulating layer 13 has multiple through holes 131 in the terminal arrangement sections 3A and 3B. More specifically, the insulating layer 13 has one through hole 131 in each of the terminal arrangement sections 3A and 3B. Note that the insulating layer 13 does not necessarily have to have through holes 131.

[0067] In this embodiment, in terminal arrangement sections 3A and 3B, the insulating layer 13 has through holes 131 at the positions where the second terminals 151A and 151B are arranged. The insulating layer 13 does not insulate the conductor layer 12 from the second terminals 151A and 151B. In other words, the insulating layer 13 does not insulate the conductor layer 12 from the second circuit pattern 15. The second terminals 151A and 151B are electrically connected to the conductor layer 12 through the through holes 131 in the insulating layer 13. In addition, in terminal arrangement sections 3A and 3B, the insulating layer 13 may be arranged between the conductor layer 12 and the second terminals 151A and 151B at locations other than the through holes 131.

[0068] The shape of the through-hole 131 when viewed from the thickness direction (plan view shape) is not particularly limited. In this embodiment, a through-hole 131 with a substantially circular shape in plan view is shown as an example. Furthermore, the cross-sectional shape of the through-hole 131 is also not particularly limited. As shown in Figure 2, in this embodiment, a through-hole 131 with a straight shape in cross-section is shown as an example.

[0069] A protective metal layer (not shown) may be placed between the conductor layer 12 and the insulating layer 13, and between the metal support layer 11 and the insulating layer 13 to protect the metal support layer 11 and the conductor layer 12. In other words, the metal support layer 11 and the conductor layer 12 may be equipped with a protective metal layer. The protective metal layer is made of metal. The protective metal layer is, for example, a sputtered layer. Examples of materials for the protective metal layer include chromium, nickel, titanium, and alloys thereof.

[0070] The insulating layer 13 is made from a resin. Examples of resins include polyimide, maleimide, epoxy resin, polybenzoxazole, and polyester. Polyimide is preferred.

[0071] The thickness of the insulating layer 13 is, for example, 1 μm or more, preferably 5 μm or more, and also, for example, 100 μm or less, preferably 50 μm or less.

[0072] (4) Circuit Pattern As shown in Figures 2 and 3, the circuit pattern is arranged on one side in the thickness direction of the conductor layer 12.

[0073] The circuit pattern comprises a first circuit pattern 14 having wiring 141 and a second circuit pattern 15 that is electrically connected to the conductor layer 12 and independent of the first circuit pattern 14. The first circuit pattern 14 preferably has wiring 141 and first terminals 142A and 142B connected to wiring 141. The second circuit pattern 15 preferably has second terminals 151A and 151B.

[0074] (4-1) First Circuit Pattern The first circuit pattern 14 is positioned on one side in the thickness direction of the insulating layer 13. In other words, the first circuit pattern 14 is in contact with one side in the thickness direction of the insulating layer 13. Also, the first circuit pattern 14 is positioned on one side in the thickness direction of the conductor layer 12. The first circuit pattern 14 overlaps with the entire conductor layer 12 in the thickness direction. The first circuit pattern 14 is positioned on the opposite side of the conductor layer 12 from the insulating layer 13 in the thickness direction. The first circuit pattern 14 is positioned away from the conductor layer 12 in the thickness direction. The first circuit pattern 14 is independent of the conductor layer 12.

[0075] The first circuit pattern 14 is made of metal. Examples of metals include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. Preferably, the first circuit pattern 14 is made of copper. In this embodiment, the wiring 141 of the first circuit pattern 14 and the first terminals 142A and 142B of the first circuit pattern 14 are made of the same metal. The planar shape of the first circuit pattern 14 is not limited.

[0076] The first circuit pattern 14 has a plurality of wires 141. Preferably, it comprises a plurality of wires 141 and a plurality of first terminals 142A, 142B connected to the wires 141.

[0077] [wiring] Multiple wires 141 are arranged in the wiring section 2. A portion of each of the multiple wires 141 may be arranged in the terminal arrangement sections 3A and 3B.

[0078] The wiring 141 is arranged on one side in the thickness direction of the insulating layer 13. Furthermore, the wiring 141 is arranged on one side in the thickness direction of the conductor layer 12. Therefore, the transmission loss of the wiring 141 can be reduced.

[0079] In wiring section 2, each of the multiple wires 141 extends in a first direction. In wiring section 2, the multiple wires 141 are arranged in a second direction. The multiple wires 141 are spaced apart from each other in the second direction. The wires 141 electrically connect the first terminal 142A and the first terminal 142B. Specifically, one end of the wire 141 in the first direction is connected to the first terminal 142A, and the other end of the wire 141 in the first direction is connected to the first terminal 142B.

[0080] Examples of wiring 141 include signal wiring (e.g., differential wiring), power wiring, ground wire, and antenna wire.

[0081] As shown in Figure 3, the cross-sectional shape of wiring 141 is approximately rectangular.

[0082] The thickness of the wiring 141 is, for example, 5 μm to 50 μm, preferably 7 μm to 45 μm.

[0083] The widthwise length of the wiring 141 is, for example, 1 μm or more, preferably 5 μm or more, and also, for example, 50 μm or less, preferably 30 μm or less.

[0084] Preferably, the length of the wiring 141 in the width direction is shorter than the length W12 of the conductor layer 12 in the width direction in the wiring section 2.

[0085] [1st terminal] Multiple first terminals 142A are arranged in the terminal arrangement section 3A. Multiple first terminals 142A are arranged along the second direction. Multiple first terminals 142A are spaced apart from each other in the second direction. Each of the multiple first terminals 142A is connected to one end of each of the multiple wires 141 in the first direction.

[0086] Multiple first terminals 142B are arranged in the terminal arrangement section 3B. Multiple first terminals 142B are arranged along the second direction. Multiple first terminals 142B are spaced apart from each other in the second direction. Each of the multiple first terminals 142B is connected to the other end in the first direction of each of the multiple wirings 141.

[0087] In terminal arrangement sections 3A and 3B, the multiple first terminals 142A and 142B are arranged on one side in the thickness direction of the insulating layer 13.

[0088] Each of the multiple first terminals 142A and 142B has, for example, a corner land shape. The cross-sectional shape (not shown) of each of the multiple first terminals 142A and 142B is not particularly limited, and is, for example, substantially rectangular.

[0089] The thickness of the first terminals 142A and 142B is, for example, 5 μm to 50 μm, preferably 7 μm to 45 μm. The thickness of the first terminals 142A and 142B may be the same as or different from the thickness of the wiring 141. In this embodiment, the thickness of the first terminals 142A and 142B is the same as the thickness of the wiring 141.

[0090] The widthwise length of the first terminals 142A and 142B is, for example, 15 μm or more, preferably 40 μm or more, and also, for example, 500 μm or less, preferably 300 μm or less. The widthwise length of the first terminals 142A and 142B is preferably longer than the widthwise length of the wiring 141. Note that the widthwise length of the first terminals 142A and 142B indicates the maximum widthwise length.

[0091] (4-2) Second Circuit Pattern The second circuit pattern 15 is electrically connected to the conductor layer 12. The arrangement of the second circuit pattern 15 is not particularly limited as long as it is electrically connected to the conductor layer 12. In this embodiment, as shown in Figure 2, the second circuit pattern 15 is electrically connected to the conductor layer 12 through the through-hole 131 of the insulating layer 13. In other words, the second circuit pattern 15 is positioned in the through-hole 131 of the insulating layer 13 and in contact with one side of the conductor layer 12 in the thickness direction. Note that a portion of the second circuit pattern 15 may be positioned on one side of the insulating layer 13 in the thickness direction. More specifically, in this embodiment, the second circuit pattern 15 is positioned in the through-hole 131 of the insulating layer 13 and on one side of the insulating layer 13 in the thickness direction. Furthermore, the second circuit pattern 15 is independent of the first circuit pattern 14.

[0092] If the insulating layer 13 does not have through holes 131, the second circuit pattern 15 is arranged on one side of the insulating layer 13 in the thickness direction and on the side of the insulating layer 13 in the surface direction, and is electrically connected to the conductor layer 12.

[0093] The second circuit pattern 15 is made of a metal. Examples of metals include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. Preferably, the second circuit pattern 15 is made of copper. Alternatively, the second circuit pattern 15 may be made of the same metal as the first circuit pattern 14. The planar shape of the second circuit pattern 15 is not limited.

[0094] The second circuit pattern 15 includes, for example, multiple second terminals 151A and 151B. The second circuit pattern 15 does not include any wiring.

[0095] [Second terminal] The second terminals 151A and 151B are located in terminal arrangement sections 3A and 3B. Specifically, in terminal arrangement sections 3A and 3B, the second terminals 151A and 151B are located in through holes 131 of the insulating layer 13 and connected to the conductor layer 12. The second terminals 151A and 151B are connected to the conductor layer 12 through the through holes 131 of the insulating layer 13.

[0096] The second terminal 151A is located in the terminal arrangement section 3A. In this embodiment, one second terminal 151A is located in the terminal arrangement section 3A. However, multiple second terminals 151A may be located in the terminal arrangement section 3A. Furthermore, the arrangement of the second terminal 151A in the terminal arrangement section 3A is not particularly limited. In this embodiment, the second terminal 151A is located away from the first terminal 142A on one side in the first direction.

[0097] The second terminal 151A is connected to the conductor layer 12 through a through-hole 131 in the insulating layer 13. More specifically, in the terminal arrangement section 3A, the metal that forms the second terminal 151A (second circuit pattern 15) is filled into the through-hole 131 in the insulating layer 13 to form the second terminal 151A, and the second terminal 151A and the conductor layer 12 are electrically connected by contact. The second terminal 151A is not connected to the wiring 141 or the first terminal 142A.

[0098] The second terminal 151B is located in the terminal arrangement section 3B. In this embodiment, one second terminal 151B is located in the terminal arrangement section 3B. However, multiple second terminals 151B may be located in the terminal arrangement section 3B. Furthermore, the arrangement of the second terminal 151B in the terminal arrangement section 3B is not particularly limited. In this embodiment, the second terminal 151B is located away from the first terminal 142B on the other side in the first direction.

[0099] The second terminal 151B is connected to the conductor layer 12 through a through-hole 131 in the insulating layer 13. More specifically, in the terminal arrangement section 3B, the metal forming the second terminal 151B (second circuit pattern 15) is filled into the through-hole 131 in the insulating layer 13 to form the second terminal 151B, and the second terminal 151B and the conductor layer 12 are electrically connected by contact. The second terminal 151B is not connected to the wiring 141 or the first terminal 142B.

[0100] Each of the multiple second terminals 151A and 151B has, for example, a square land shape.

[0101] The cross-sectional shapes of the multiple second terminals 151A and 151B are not particularly limited, and examples include a roughly rectangular shape and a roughly T-shape.

[0102] The thickness of the second terminals 151A and 151B is, for example, 5 μm to 50 μm, preferably 7 μm to 45 μm. The thickness of the second terminals 151A and 151B may be the same as or different from the thickness of the wiring 141 and the first terminals 142A and 142B. In this embodiment, the thickness of the second terminals 151A and 151B is the same as the thickness of the wiring 141 and the first terminals 142A and 142B.

[0103] The widthwise length of the second terminals 151A and 151B is, for example, 15 μm or more, preferably 40 μm or more, and also, for example, 500 μm or less, preferably 300 μm or less. The widthwise length of the second terminals 151A and 151B is preferably longer than the widthwise length of the wiring 141. Note that the widthwise length of the second terminals 151A and 151B indicates the maximum widthwise length.

[0104] (6) Cover insulation layer As shown in Figures 1 and 2, the cover insulating layer 16 covers all the wiring 141 in the wiring section 2. The cover insulating layer 16 may also cover at least a portion of the wiring 141 located in the terminal arrangement sections 3A and 3B.

[0105] As shown in Figures 1 and 2, the cover insulating layer 16 does not cover the first terminals 142A and 142B and the second terminals 151A and 151B.

[0106] The cover insulating layer 16 is positioned on one side in the thickness direction of the insulating layer 13 (base insulating layer). The cover insulating layer 16 is made of resin. Examples of resins include polyimide, maleimide, epoxy resin, polybenzoxazole, and polyester. Polyimide is preferred.

[0107] 2. Manufacturing method of a wiring circuit board Next, the manufacturing method of the wiring circuit board 1 will be described with reference to Figures 4A to 5B.

[0108] The manufacturing method for the wiring circuit board 1 includes a conductor layer formation step (see Figure 4A), an insulating layer formation step (see Figure 4B), a circuit pattern formation step (see Figure 4C), a cover insulating layer formation step (see Figure 5A), and an etching step (Figure 5B).

[0109] (1) Conductor layer formation process As shown in Figure 4A, in the conductive layer formation process, a conductive layer 12 is formed on one side in the thickness direction of a metal substrate M (for example, metal foil).

[0110] In more detail, first, the aforementioned bonding layer (not shown) is formed on one side in the thickness direction of the base material M. The bonding layer is formed, for example, by sputtering.

[0111] Next, the bonding layer is covered with a plating resist.

[0112] Next, the plating resist is exposed and developed. This removes the plating resist in the areas where the conductive layer 12 will be formed, exposing the bonding layer in those areas. On the other hand, the plating resist remains in the areas where the conductive layer 12 will not be formed.

[0113] Next, a conductive layer 12 is formed on one side of the exposed bonding layer in the thickness direction by electroplating. After the electroplating is completed, the plating resist is peeled off.

[0114] As a result, a conductive layer 12 is formed on one side of the substrate M in the thickness direction.

[0115] Furthermore, when forming a conductive layer 12 over the entire surface of one side in the thickness direction of the substrate M, the above-mentioned steps of coating with plating resist, exposure, and development are omitted.

[0116] (2) Insulating layer formation process (base insulating layer formation process) Next, as shown in Figure 4B, in the insulating layer formation process, an insulating layer 13 (base insulating layer) is formed on one side in the thickness direction of the conductor layer 12.

[0117] More specifically, in the insulating layer formation process, first, the protective metal layer (not shown) described above is formed on one side in the thickness direction of the substrate M and the conductor layer 12. The protective metal layer is formed, for example, by sputtering.

[0118] Next, a photosensitive resin solution (varnish) is applied to one side in the thickness direction of the substrate M and the conductor layer 12 (one side in the thickness direction of the protective metal layer) and dried to form a photosensitive resin coating. Then, the photosensitive resin coating is exposed to light and developed. This gives rise to the insulating layer 13.

[0119] Although not shown in the diagram, in terminal arrangement sections 3A and 3B, the insulating layer 13 is not placed at the locations where through-holes 131 are to be formed in the insulating layer 13. Specifically, after forming a photosensitive resin coating on one side in the thickness direction of the substrate M and the conductor layer 12 (one side in the thickness direction of the protective metal layer), the locations where through-holes 131 are to be formed are shielded from light using a photomask or the like. Then, during development, the insulating layer 13 in the shielded area is removed, and through-holes 131 are formed.

[0120] (3) Circuit pattern formation process Next, as shown in Figure 4C, the circuit pattern formation process involves forming a circuit pattern. Specifically, a first circuit pattern 14 is formed on one side in the thickness direction of the insulating layer 13, and a second circuit pattern 15 is formed on one side in the thickness direction of the conductor layer 12 through the through-hole 131 of the insulating layer 13.

[0121] More specifically, a seed layer (not shown) is first formed on one surface in the thickness direction of the insulating layer 13, on the inner circumferential surface of the through hole 131 of the insulating layer 13, and on one surface in the thickness direction of the conductor layer 12 exposed in the through hole 131 of the insulating layer 13. The seed layer is formed, for example, by sputtering. Examples of materials for the seed layer include chromium, copper, nickel, titanium, and alloys thereof.

[0122] Next, a plating resist is bonded to one side in the thickness direction of the seed layer, and the plating resist is exposed while shielding the areas where the wiring 141 of the first circuit pattern 14, the first terminals 142A and 142B of the first circuit pattern 14, and the second terminals 151A and 151B of the second circuit pattern 15 will be formed.

[0123] Next, the exposed plating resist is developed. This removes the plating resist from the light-shielded areas, exposing the seed layer in the areas where the wiring 141 of the first circuit pattern 14, the first terminals 142A and 142B of the first circuit pattern 14, and the second terminals 151A and 151B of the second circuit pattern 15 are formed. Meanwhile, the plating resist remains in the exposed areas.

[0124] Next, the wiring 141 of the first circuit pattern 14, the first terminals 142A and 142B of the first circuit pattern 14, and the second terminals 151A and 151B of the second circuit pattern 15 are formed on the exposed seed layer by electroplating.

[0125] After forming the wiring 141 of the first circuit pattern 14, the first terminals 142A and 142B of the first circuit pattern 14, and the second terminals 151A and 151B of the second circuit pattern 15, the plating resist is peeled off.

[0126] (4) Cover insulating layer formation process Next, as shown in Figure 5A, in the cover insulating layer formation step, a cover insulating layer 16 is formed so as to cover one side in the thickness direction of the insulating layer 13 and the circuit pattern. The cover insulating layer 16 is formed, for example, in the same manner as the insulating layer 13 described above.

[0127] (5) Etching process Next, in the etching process, the substrate M is etched to form the metal support layer 11 shown in Figure 5B.

[0128] This results in the manufacture of the wiring circuit board 1 shown in Figure 1.

[0129] 3. Effects (1) According to the wiring circuit board 1, in the wiring section 2, the length in the width direction of the conductor layer 12 is the length in the width direction of at least a part of the thickness direction of the metal support layer 11 (minimum width direction length W11 min It is longer than ). Therefore, electrical resistance can be reduced.

[0130] In detail, the wiring circuit board 1 is required to be miniaturized, and in the wiring section 2, the length of the metal support layer 11 in the width direction must not be excessively long. Therefore, in the wiring section 2, the length of the conductor layer 12 in the width direction must be set to the length of at least a portion of the length of the metal support layer 11 in the thickness direction (minimum width direction length W11). min By making it longer, miniaturization can be achieved while reducing electrical resistance.

[0131] (2) The wiring circuit board 1 comprises a metal support layer 11, a conductor layer 12, an insulating layer 13, and a circuit pattern arranged in order toward one side in the thickness direction, and the circuit pattern comprises a first circuit pattern 14 having wiring 141. In other words, the wiring 141 is formed on one side in the thickness direction of the conductor layer 12. Therefore, the transmission loss of the wiring 141 can be reduced.

[0132] (3) According to the wiring circuit board 1, in the wiring section 2, the widthwise length W12 of the conductor layer 12 is the widthwise length of at least a part of the thicknesswise length of the metal support layer 11 (minimum widthwise length W11 min ) is longer than, and in the wiring section 2, the widthwise length W12 of the conductor layer 12 is equal to the widthwise length W11 of the central part in the thickness direction of the metal support layer 11. C It is longer. Therefore, electrical resistance can be reduced even further.

[0133] (4) According to the wiring circuit board 1, the circuit pattern includes a second circuit pattern 15 independent of the first circuit pattern 14, and the insulating layer 13 includes through holes 131. The second circuit pattern 15 is electrically connected to the conductor layer 12 through the through holes 131. Therefore, the second circuit pattern 15 can be reliably connected to the conductor layer 12.

[0134] (5) According to the wiring circuit board 1, the first circuit pattern 14 has first terminals 142A and 142B connected to the wiring 141, and the second circuit pattern 15 has second terminals 151A and 151B. The first terminals 142A and 142B and the second terminals 151A and 151B are arranged in the terminal arrangement section 3. In the terminal arrangement section 3, the second terminals 151A and 151B are arranged in the through holes 131. Therefore, the second circuit pattern 15 is made independent from the first circuit pattern 14, and the second terminals 151A and 151B can be reliably connected to the conductor layer 12.

[0135] (6) According to the wiring circuit board 1, the minimum widthwise length W11 of the metal support layer 11 in the wiring section 2 min The ratio of the length W12 in the width direction of the conductor layer 12 to the length is 1.2 or greater. Therefore, electrical resistance can be reduced even further.

[0136] (7) According to the wiring circuit board 1, in the wiring section 2, the length W11 in the width direction of the center of the metal support layer 11 in the thickness direction C The ratio of the length W12 in the width direction of the conductor layer to the length is 1.2 or greater. Therefore, electrical resistance can be reduced even further.

[0137] (8) In the wiring circuit board 1, the ratio of the thickness of the conductor layer 12 to the thickness of the metal support layer 11 is 0.003 or more. Therefore, electrical resistance can be reduced even further.

[0138] 5. Variations Next, a modified example will be described. In the modified example, the same reference numerals are used for components similar to those in the above-described embodiment, and their descriptions are omitted.

[0139] (1) In one embodiment of the wiring circuit board 1 described above, the cross-sectional shape of the metal support layer 11 in the wiring section 2 is substantially rectangular, and the length of the metal support layer 11 in the width direction is substantially the same in the thickness direction, but is not limited to this.

[0140] As shown in Figure 6, in the first modified wiring circuit board 1, the cross-sectional shape of the metal support layer 11 in the wiring section 2 is approximately T-shaped.

[0141] In the wiring section 2, the widthwise length of one end of the metal support layer 11 in the thickness direction is longer than the widthwise lengths of the central and other ends of the metal support layer 11 in the thickness direction. In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max This is the length in the width direction of one end of the metal support layer 11 in the thickness direction.

[0142] In the wiring section 2, the length W11 in the width direction of the center of the metal support layer 11 in the thickness direction C The minimum widthwise length W11 of the metal support layer 11 min It is the same as this.

[0143] In other words, in the first modified wiring circuit board 1, the length in the width direction of the metal support layer 11 in the wiring section 2 is W11 max >W11 min =W11 C That is the case.

[0144] (2) As shown in Figure 7, in the second modified wiring circuit board 1, the cross-sectional shape of the metal support layer 11 in the wiring section 2 is approximately an inverted T shape.

[0145] In the wiring section 2, the widthwise length of the other end of the metal support layer 11 in the thickness direction is longer than the widthwise lengths of the one end and the central part of the metal support layer 11 in the thickness direction. In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max This is the length in the width direction of the other end of the metal support layer 11 in the thickness direction.

[0146] In the wiring section 2, the length W11 in the width direction of the center of the metal support layer 11 in the thickness direction C The minimum widthwise length W11 of the metal support layer 11 min It is the same as this.

[0147] In other words, in the second modified wiring circuit board 1, the length in the width direction of the metal support layer 11 in the wiring section 2 is W11 max>W11 min =W11 C That is the case.

[0148] (3) As shown in Figure 8, in the wiring circuit board 1 of the third modified example, the cross-sectional shape of the metal support layer 11 in the wiring section 2 is approximately I-shaped.

[0149] In the wiring section 2, the widthwise lengths of one end and the other end of the metal support layer 11 in the thickness direction are equal to the widthwise length W11 of the central part of the metal support layer 11 in the thickness direction. C Longer. In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max This is the length in the width direction of one end and / or the other end of the metal support layer 11 in the thickness direction.

[0150] In the wiring section 2, the widthwise lengths of one end and the other end of the metal support layer 11 in the thickness direction are equal to the widthwise length W11 of the central part of the metal support layer 11 in the thickness direction. C If the length is increased, the surface area of ​​the metal support layer 11 in the wiring section 2 can be increased. As a result, heat dissipation can be improved. In addition, in the second direction, the risk of contact between the metal support layers 11 in adjacent wiring sections 2 can be reduced.

[0151] In the wiring section 2, the length W11 in the width direction of the center of the metal support layer 11 in the thickness direction C The minimum widthwise length W11 of the metal support layer 11 min It is the same as this.

[0152] In other words, in the third modified wiring circuit board 1, the length in the width direction of the metal support layer 11 in the wiring section 2 is W11 max >W11 min =W11 C That is the case.

[0153] (4) As shown in Figure 9, in the wiring circuit board 1 of the fourth modified example, in the wiring section 2, the metal support layer has a substantially tapered shape in cross-section, widening from one side to the other in the thickness direction. In other words, in the wiring section 2, the cross-sectional shape of the metal support layer 11 is substantially tapered, widening from one side to the other in the thickness direction.

[0154] In the wiring section 2, the widthwise length of one end of the metal support layer 11 in the thickness direction is longer than the widthwise lengths of the central and other ends of the metal support layer 11 in the thickness direction. In the wiring section 2, the maximum widthwise length W11 of the metal support layer 11 max This is the widthwise length of one end of the metal support layer 11 in the thickness direction. Furthermore, in the wiring section 2, the widthwise length of the central part of the metal support layer 11 in the thickness direction is longer than the widthwise length of the other end of the metal support layer 11 in the thickness direction.

[0155] In the wiring section 2, the length W11 in the width direction of the center of the metal support layer 11 in the thickness direction C The maximum widthwise length W11 of the metal support layer 11 max and minimum widthwise length W11 min It is different.

[0156] In other words, in the wiring circuit board 1 of the fourth modified example, the length in the width direction of the metal support layer 11 in the wiring section 2 is W11 max >W11 C >W11 min That is the case.

[0157] (5) In one embodiment of the wiring circuit board 1 described above, the insulating layer 13 is arranged only on one side in the thickness direction of the conductor layer 12 in the wiring section 2, but the invention is not limited to this.

[0158] As shown in Figure 10, in the fifth modified wiring circuit board 1, an insulating layer 13 is arranged in the wiring section 2 so as to cover the conductor layer 12. Specifically, in the wiring section 2, the insulating layer 13 is arranged so as to cover one side in the thickness direction and both sides in the width direction of the conductor layer 12.

[0159] In the fifth modified example of the wiring circuit board 1, the length of the wiring section 2 in the width direction is the length of the insulating layer 13 in the width direction.

[0160] (6) In one embodiment of the wiring circuit board 1 described above, in the wiring section 2, the aspect ratio of the metal support layer 11 (thickness of the metal support layer 11 / W11 max) is relatively large (e.g., 2 or more), but is not limited thereto.

[0161] As shown in FIG. 11, in the wiring circuit board 1 of the sixth modification, in the wiring portion 2, the aspect ratio of the metal support layer 11 (the thickness of the metal support layer 11 / W11 max ) is relatively small. In the wiring portion 2, the aspect ratio of the metal support layer 11 (the thickness of the metal support layer 11 / W11 max ) is, for example, 0.5 or more, preferably 1.0 or more, and, for example, less than 2, preferably 1.5 or less.

[0162] When the aspect ratio of the metal support layer 11 in the wiring portion 2 is below the above upper limit value, the wiring portion 2 can be easily deformed in the thickness direction compared to the width direction. Also, the rigidity of the wiring portion 2 in the width direction can be ensured.

Explanation of Reference Numerals

[0163] 1 Wiring circuit board 2 Wiring portion 3 Terminal arrangement portion 11 Metal support layer 12 Conductor layer 13 Insulation layer (base insulation layer) 14 First circuit pattern 15 Second circuit pattern 16 Cover insulation layer 131 Through-hole 141 Wiring 142 First terminal 151 Second terminal

Claims

1. A wiring circuit board comprising a metal support layer, a conductor layer, an insulating layer, and a circuit pattern arranged in order toward one side in the thickness direction, The circuit pattern comprises a first circuit pattern having wiring and a second circuit pattern electrically connected to the conductor layer and independent of the first circuit pattern. The aforementioned wiring circuit board includes a wiring section on which the wiring is arranged, A wiring circuit board in which, in the wiring portion, the length in the width direction perpendicular to the thickness direction of the conductor layer and the direction in which the wiring extends is longer than the length in the width direction of at least a portion of the thickness direction of the metal support layer.

2. The wiring circuit board according to claim 1, wherein in the wiring portion, the length in the width direction of the conductor layer is longer than the length in the width direction of the central part in the thickness direction of the metal support layer.

3. The wiring circuit board according to claim 1, wherein in the wiring portion, the length in the width direction of one end and the other end of the metal support layer in the thickness direction is longer than the length in the width direction of the central part of the metal support layer in the thickness direction.

4. The wiring circuit board according to claim 1, wherein the metal support layer of the wiring portion has a substantially tapered shape in cross-sectional view, widening in the width direction from one side to the other in the thickness direction.

5. The insulating layer has through holes, The wiring circuit board according to claim 1, wherein the second circuit pattern is electrically connected to the conductor layer through the through-hole.

6. The first circuit pattern has a first terminal connected to the wiring, The second circuit pattern has a second terminal, The wiring circuit board further comprises a terminal arrangement section on which the first terminal and the second terminal are arranged, In the terminal arrangement section, The insulating layer has the through holes, The wiring circuit board according to claim 5, wherein the second terminal is arranged in the through hole.

7. The wiring circuit board according to any one of claims 1 to 6, wherein in the wiring section, the ratio of the widthwise length of the conductor layer to the minimum widthwise length of the metal support layer is 1.2 or more.

8. The wiring circuit board according to any one of claims 1 to 6, wherein in the wiring portion, the ratio of the length of the conductor layer in the width direction to the length of the central part of the metal support layer in the thickness direction is 1.2 or more.

9. The wiring circuit board according to any one of claims 1 to 6, wherein the ratio of the thickness of the conductor layer to the thickness of the metal support layer is 0.003 or more.

Images