TWI823937B - Wired circuit board - Google Patents

Abstract

The printed circuit board of the present invention includes a plurality of wiring bodies arranged in parallel and spaced apart from each other. Each of the plurality of wiring bodies is provided with: an insulating part; a wiring part arranged on one side of the insulating part in the thickness direction; and a support part arranged on the other side of the insulating part in the thickness direction, and includes a metal-based material and has a thickness direction length T The ratio (T/W) to the length W of the plurality of wiring bodies in the parallel direction is 2 or more.

Description

Wired circuit board

The present invention relates to a wiring circuit board.

Previously, there has been known a heat dissipation structure in which a heat sink having a flat base and comb-shaped fins extending downward from the lower surface of the base is provided on the lower surface of a substrate with a heating element mounted on the upper surface. , and the heat generated by the self-heating element is released from the fins of the heat sink (for example, refer to the following Patent Document 1).

Prior technical literature patent documents

Patent Document 1: Japanese Patent Application Publication No. Sho 55-140255

However, in the heat dissipation structure, higher heat dissipation performance is required.

The present invention provides a printed circuit board excellent in heat dissipation properties.

The present invention (1) includes a printed circuit board provided with a plurality of wiring bodies spaced apart from each other and arranged in parallel, and each of the plurality of wiring bodies is provided with: an insulating portion; and a wiring portion arranged on the insulating portion. One side in the thickness direction; and a support portion, which is disposed on the other side in the thickness direction of the insulating portion and is made of a metal-based material, and has a ratio of the length T in the thickness direction to the length W in the parallel direction of the plurality of wiring bodies (T/W ) is 2 or more.

In this printed circuit board, since the wiring bodies are arranged side by side at intervals, the heat generated in the wiring portion can be convection through the air between the plurality of wiring bodies, thereby achieving efficient heat dissipation.

In addition, since the ratio (T/W) of the length T in the thickness direction to the length W in the parallel direction of the plurality of wiring bodies is as high as 2 or more, the supporting portion can increase the contact area with the air. Therefore, the heat dissipation efficiency based on the above-mentioned convection is excellent.

Furthermore, since the support portion has a ratio (T/W) as high as 2 or more and contains a metal-based material, the heat conducted from the wiring portion to the insulating portion can be efficiently released toward the other side in the thickness direction.

Therefore, the wiring body of this printed circuit board has excellent heat dissipation properties.

The present invention (2) includes the printed circuit board according to (1), wherein one of the supporting portions has a side surface facing the other supporting portion adjacent to the supporting portion in the parallel direction, and the area of the side surface is It is greater than the projected area when the above-mentioned side surface is projected in the above-mentioned parallel direction.

In this printed circuit board, since the area of the side surface is larger than the projected area when the side surface is projected in the parallel direction, the contact area between the side surface of the support part and the air can be reliably increased. Therefore, the self-supporting part has better heat dissipation efficiency based on convection.

The present invention (3) includes the printed circuit board according to (1) or (2), wherein the material of the support portion is metal.

In this printed circuit board, since the material of the supporting part is metal, the heat dissipation property from the supporting part is excellent.

The present invention (4) includes the printed circuit board according to any one of (1) to (3), which has an orthogonal connection between the plurality of wiring bodies and is orthogonal to the parallel direction and the thickness direction. A coupling body in which direction ends are connected, and the coupling body is provided with: a terminal portion that is continuous with the orthogonal direction end portion of the above-mentioned wiring portion; and a connection support portion that is continuous with the orthogonal direction end portion of the above-mentioned support portion; the above-mentioned connection The support portion is continuous in the parallel direction so as to include a plurality of the terminal portions when projected in the thickness direction.

In this printed circuit board, since the connection support portion is continuous in the parallel direction to include a plurality of terminal portions when projected in the thickness direction, the connection support portion can reliably support the plurality of terminal portions.

Therefore, in this printed circuit board, the wiring body has excellent heat dissipation properties, and the terminal portion in the connector also has excellent mechanical strength.

The wiring body of the printed circuit board of the present invention has excellent heat dissipation properties.

1:Wiring circuit board

2: 1st connection

3: 2nd connection

4: Wiring body

5:Opening part

6: Metal support layer

7: Base insulation layer

8: Conductor layer

9: Cover with insulation layer

10: Main wiring department

11: 1st terminal part

12: 2nd terminal part

13: 1st connecting metal part

14: 2nd connecting metal part

15: Wiring body metal part

16: 1st connection base

17: 2nd connection base

18: Wiring body base

19: 1st auxiliary wiring section

20: 2nd auxiliary wiring section

21: 1st metal surface

22: 2nd metal surface

23:Metal side

24: 1st basal surface

25: 2nd basal surface

26: Basal side

27: 1st conductor surface

28: 2nd conductor surface

29:Conductor side

31:Metal inner side

32:Metal outer side

33: Wiring body covering part

34: 1st Coverage

35: 2nd coverage

36: Cover the sides

37: Medial surface of base

38: Cover the inner side

41: 1st component

42: 2nd component

43: 1st electrode

44: 2nd electrode

50: Wiring body side

51: Inside side of wiring

T:Thickness

W:length

FIG. 1 shows a plan view of an embodiment of a printed circuit board according to the present invention.

2A and 2B are cross-sectional views of the printed circuit board shown in FIG. 1 . FIG. 2A shows a cross-sectional view along line A-A, and FIG. 2B shows a cross-sectional view along line B-B.

The overall structure of the wiring circuit board

An embodiment of the printed circuit board of the present invention will be described with reference to FIGS. 1 , 2A and 2B. In addition, in FIG. 1 , in order to clearly show the relative arrangement of the metal-based support layer 6 and the conductor layer 8 described below, the base insulating layer 7 and the cover insulating layer 9 described below are omitted.

This printed circuit board 1 has one surface and another surface in the thickness direction, and has a shape extending in a longitudinal direction orthogonal to the thickness direction. As shown in Fig. 1, the printed circuit board 1 is integrally It is provided with the 1st coupling body 2 as an example of a coupling body, the 2nd coupling body 3 as an example of a coupling body, and the wiring body 4. It is preferable that the printed circuit board 1 includes only the first connecting body 2 , the second connecting body 3 and the wiring body 4 .

The first connecting body 2 forms one longitudinal end portion of the printed circuit board 1 . The first connecting body 2 has a substantially rectangular flat plate shape in plan view. The size of the first connecting body 2 in plan view is not particularly limited.

The second connecting body 3 forms the other longitudinal end of the printed circuit board 1 and is disposed facing the first connecting body 2 on the other longitudinal side with the wiring body 4 interposed therebetween. The second connecting body 3 has a substantially rectangular flat plate shape in plan view. The size of the second coupling body 3 in plan view is not particularly limited.

The wiring body 4 forms the longitudinal middle portion (or central portion) of the printed circuit board 1 . The wiring body 4 is arranged between the first connecting body 2 and the second connecting body 3 in plan view. The wiring body 4 has a shape extending in the longitudinal direction. The wiring body 4 bridges the first connecting body 2 and the second connecting body 3 in the longitudinal direction. In addition, a plurality of wiring bodies 4 are arranged in parallel with slightly longer intervals in the short side direction (the direction orthogonal to the length direction and the thickness direction) of the printed circuit board 1 (an example of the parallel direction of the wiring bodies 4). . An opening 5 is formed between adjacent wiring bodies 4 .

The opening 5 separates the wiring body 4 in the short side direction of the printed circuit board 1 , for example. The opening 5 has a slit shape extending in the longitudinal direction, and penetrates the printed circuit board 1 in the thickness direction.

One end portions of the plurality of wiring bodies 4 in the longitudinal direction are connected in the short side direction by one first connecting body 2 . Thereby, one end portion in the longitudinal direction of the plurality of wiring bodies 4 is bundled by the one first connecting body 2 .

In addition, the other ends in the longitudinal direction of the plurality of wiring bodies 4 are connected in the short side direction by one second connecting body 3 . Thereby, the other ends in the longitudinal direction of the plurality of wiring bodies 4 are formed by one The second connection 3 is closed.

The longitudinal length of the wiring body 4 is the distance between the first connecting body 2 and the second connecting body 3 in the longitudinal direction, and is appropriately set according to the use and purpose.

The short side direction length of each of the plurality of wiring bodies 4 is, for example, 500 μm or less, preferably 300 μm or less, more preferably 100 μm or less, and, for example, 10 μm or more. The short side direction length of the opening 5 is, for example, 10 μm or more, preferably 50 μm or more, more preferably 100 μm or more, and, for example, 1000 μm or less. The ratio of the short-side length of the wiring body 4 to the short-side length of the opening 5 is, for example, 40 or less, preferably 10 or less, and is, for example, 0.1 or more, preferably 0.5 or more.

Layer structure of printed circuit board

As shown in FIGS. 2A and 2B , the printed circuit board 1 includes: a metal support layer 6 ; a base insulating layer 7 disposed on one side of the metal support layer 6 in the thickness direction; and a conductor layer 8 disposed on the base insulating layer. one side in the thickness direction of the base insulating layer 7; and a covering insulating layer 9, which is disposed on one side in the thickness direction of the base insulating layer 7 in a manner that partially covers the conductor layer 8. The printed circuit board 1 preferably includes only the metal support layer 6 , the base insulating layer 7 , the conductor layer 8 and the cover insulating layer 9 .

The metal support layer 6 forms the other surface of the printed circuit board 1 in the thickness direction. As shown in FIG. 1 , FIG. 2A and FIG. 2B , the metal-based support layer 6 has the same outer shape as the printed circuit board 1 . Specifically, the metal-based support layer 6 has an outer shape corresponding to the first connecting body 2 , the second connecting body 3 , and the wiring body 4 . In the metal support layer 6, the portion forming the first coupling body 2 is the first coupling metal portion 13 as an example of the coupling support portion, and the portion forming the second coupling body 3 is a second coupling as an example of the coupling support portion. The metal part 14 forms the wiring body 4 and is the wiring body metal part 15 as an example of a supporting part.

The first connecting metal part 13 has a plurality of first ends as shown below in plan view. The sub-section 11 is in the form of a substantially flat plate shape that is continuous in the short side direction.

The second connecting metal portion 14 has a substantially flat plate shape in plan view that is continuous in the short side direction and includes a plurality of second terminal portions 12 described below.

The wiring body metal portion 15 defines the other side portion of the opening 5 in the thickness direction. The wiring body metal portion 15 has a substantially rectangular shape that is long in the thickness direction in a cross section (which is synonymous with cross-sectional view) cut along the thickness direction and the short side direction.

In addition, the metal-based support layer 6 integrally includes a first metal surface 21 as one surface in the thickness direction, a second metal surface 22 as the other surface in the thickness direction, and a metal side surface as a side surface connecting their peripheral edges in the thickness direction. twenty three.

The first metal surface 21 and the second metal surface 22 are flat surfaces that are opposite and parallel in the thickness direction.

The metal side surface 23 is a flat surface extending straight along the thickness direction. In addition, the metal side surface 23 of the wiring body metal portion 15 is also a flat surface extending straight along the length direction. The metal side surface 23 of the wiring body metal part 15 includes a metal inner side surface 31 facing the opening 5 and a metal outer side surface 32 facing the transverse direction outer side.

The metal inner side surface 31 is an example of a side surface facing another wiring body metal part 15 adjacent to one wiring body metal part 15 in the short side direction. The two metal inner side surfaces 31 facing each other across the opening 5 are parallel, and are also parallel to the conductor side surface 29 of the main wiring portion 10 described below in plan view. Furthermore, the area S0 of the metal inner surface 31 is the same as the projected area S1 when the metal inner surface 31 is projected in the short-side direction because the wiring body metal portion 15 has a substantially rectangular shape when viewed in cross section. The area S0 of the metal inner surface 31 is a value obtained by multiplying the thickness T of the metal support layer 6 to be described next by the length in the longitudinal direction.

The thickness T of the metal support layer 6 is the relationship between the first metal surface 21 and the second metal surface 22 The length in the thickness direction is the length of the metal side surface 23 . Specifically, the thickness T of the metal support layer 6 is, for example, 30 μm or more, preferably 50 μm or more, preferably 100 μm or more, preferably 250 μm or more, preferably 500 μm or more, preferably 1000 μm or more, and, for example, is less than 10mm.

The short-side direction length W of the wiring body metal portion 15 can be appropriately selected from the range illustrated with respect to the short-side direction length of the wiring body 4 . Specifically, the short-side direction length W of the wiring body metal portion 15 is the same as the short-side direction length W of the wiring body 4 . The short side lengths are the same. Furthermore, in the plurality of wiring bodies 4 , the short-side direction length W of the wiring body metal portion 15 is the distance (length) between two adjacent metal inner surfaces 31 .

In addition, the ratio (T/W) of the thickness T of the wiring body metal portion 15 to the short-side direction length W of the wiring body metal portion 15 is 2 or more. In addition, the ratio (T/W) corresponds to the aspect ratio in the cross section obtained by cutting the wiring body metal portion 15 in the thickness direction and the short side direction. If the aspect ratio (T/W) is less than 2, the air in the opening 5 cannot be used to efficiently release the heat generated in the main wiring portion 10 (described below) in the wiring body 4 .

Moreover, the aspect ratio (T/W) is preferably 2.5 or more, more preferably 3 or more, still more preferably 3.5 or more, and is 1000 or less, further preferably 100 or less. If the ratio (T/W) is equal to or higher than the above lower limit, the heat generated in the main wiring portion 10 of the wiring body 4 can be efficiently released using the air in the opening portion 5 .

The material of the metal-based support layer 6 can be appropriately selected and used, for example, from known or commonly used metal-based materials (specifically, metal materials). Specifically, examples of metal-based materials include metal elements classified into Group 1 to Group 16 in the periodic table, alloys containing two or more of these metal elements, and the like. Furthermore, the metal-based material may be either a transition metal or a typical metal. More specifically, examples of metal-based materials include calcium and the like. Group 4 metal elements; titanium, zirconium and other Group 4 metal elements; vanadium and other Group 5 metal elements; chromium, molybdenum, tungsten and other Group 6 metal elements; manganese and other Group 7 metal elements; iron and other Group 8 metal elements; Group 9 metal elements such as cobalt; Group 10 metal elements such as nickel and platinum; Group 11 metal elements such as copper, silver, and gold; Group 12 metal elements such as zinc; Group 13 metal elements such as aluminum and gallium; Germanium, Tin and other Group 14 metallic elements. These can be used alone or in combination.

Furthermore, the first connecting metal part 13 , the second connecting metal part 14 and the wiring body metal part 15 are made of the same material.

Furthermore, the metal support layer 6 includes a metal support layer made of metal.

The thermal conductivity of the metal support layer 6 is, for example, 5W/m. K or above, preferably 10W/m. K or above, and more preferably 15W/m. K or above, 20W/m． K or above, 25W/m． K or above, 30W/m． K or above, 35W/m． K or above, 40W/m． K or above, 50W/m． K or above, 60W/m． K or above, 75W/m． K or above, 100W/m． K or above, 200W/m. K or above, 300W/m． K or above, 350W/m. K or above. If the thermal conductivity of the metal-based supporting layer 6 is equal to or higher than the above-mentioned lower limit, the heat conducted from the main wiring portion 10 to the wiring body base portion 18 can be efficiently released toward the other side in the thickness direction.

The thermal conductivity of the metal-based support layer 6 is determined based on JIS H 7903:2008 (effective thermal conductivity measurement method).

The base insulating layer 7 is, for example, disposed on the entire first metal surface 21 of the metal support layer 6 . Specifically, the base insulating layer 7 has an outer shape corresponding to the first connecting body 2 , the second connecting body 3 , and the wiring body 4 . In the base insulating layer 7, the portion where the first connector 2 is formed is the first connection base portion 16, the portion where the second connector 3 is formed is the second connection base portion 17, and the portion where the wiring body 4 is formed serves as an insulating portion. An example is the wiring body base 18.

The first connection base part 16 is arranged on the entire first metal surface of the first connection metal part 13 twenty one. The second connection base portion 17 is arranged on the entire first metal surface 21 of the second connection metal portion 14 .

The wiring body base portion 18 is disposed on the entire first metal surface 21 of the wiring body metal portion 15 . In other words, the wiring body metal portion 15 is arranged on the other surface in the thickness direction of the wiring body base portion 18 (the second base surface 25 to be described below). In addition, the wiring body base portion 18 defines the opening 5 together with the wiring body metal portion 15 described above and the wiring body covering portion 33 described below.

Furthermore, the base insulating layer 7 integrally includes a first base surface 24 as one surface in the thickness direction, a second base surface 25 as the other surface in the thickness direction, and a base side surface 26 as a side surface connecting their peripheral edges in the thickness direction. .

The first base surface 24 is a flat surface parallel to the first metal surface 21 .

The second base surface 25 is a flat surface in contact with the first metal surface 21 .

The base side surface 26 is a flat surface extending straight along the thickness direction. In addition, the base side surface 26 is formed flush with the metal side surface 23 in the thickness direction of the wiring body base portion 18 . Furthermore, the base side surface 26 has a base inner side surface 37 formed in the same plane as the metal inner side surface 31 in the wiring body base portion 18 . The base inner surface 37 partially defines the opening 5 .

The thickness of the base insulating layer 7 is the opposing length of the first base surface 24 and the first metal surface 21, and is the thickness direction length of the base side surface 26. Specifically, it is, for example, 1 μm or more, preferably 5 μm or more, and, For example, it is 100 μm or less, preferably 50 μm or less. The ratio of the thickness of the base insulating layer 7 to the thickness T of the metal support layer 6 is, for example, 10 or less, preferably 1 or less, more preferably 0.1 or less, and, for example, 0.005 or more.

Examples of the material of the base insulating layer 7 include insulating resins such as polyimide.

Furthermore, the thermal conductivity of the base insulating layer 7 is lower than the thermal conductivity of the metal support layer 6. Specifically, it is, for example, 1 W/m. K or less, and then 0.5W/m. Below K, again, for example is 0.01W/m. K or above, preferably 0.1W/m. K or above.

The thermal conductivity of the base insulating layer 7 was determined based on JIS A 1412 (Measurement of thermal conductivity of thermal insulating materials).

The conductor layer 8 is arranged on the first base surface 24 of the base insulating layer 7 . Specifically, the conductor layer 8 is arranged on the first base surface 24 of the first connection base portion 16 , the second connection base portion 17 , and the wiring body base portion 18 .

In the conductor layer 8, the portion included in the first connector 2 is the first terminal portion 11 and the first auxiliary wiring portion 19, and the portion included in the second connector 3 is the second terminal portion 12 and the second auxiliary wiring portion 20. , the portion included in the wiring body 4 is the main wiring portion 10 as an example of the wiring portion.

A plurality of first terminal portions 11 are arranged in the first connecting body 2 at intervals in the short side direction of the printed circuit board 1 corresponding to the plurality of wiring bodies 4 (main wiring portions 10 ). The plurality of first terminal portions 11 are arranged at intervals in the short side direction so as to be included in the first connecting metal portion 13 when projected in the thickness direction.

The first terminal portion 11 is arranged on the first base surface 24 of the first connecting base portion 16 . The first terminal portion 11 is disposed at one longitudinal end and a central portion of the first base surface 24 to ensure an area for forming the first auxiliary wiring portion 19 at the other longitudinal end of the first base surface 24 . The first terminal portion 11 has a substantially rectangular shape (square pad shape) in plan view.

The first auxiliary wiring portion 19 is arranged on the first base surface 24 of the first connecting base portion 16 in the first connecting body 2 so as to be continuous with the first terminal portion 11 . The first auxiliary wiring 19 has a substantially linear shape in plan view extending from the other longitudinal end edge of the first terminal portion 11 toward the other longitudinal side. The first auxiliary wiring part 19 connects the other longitudinal end edge of the first terminal part 11 and the one longitudinal end edge of the main wiring part 10 to be described next. The length of the first auxiliary wiring 19 in the transverse direction is shorter than the length of the first terminal portion 11 in the transverse direction. The short side of the first auxiliary wiring 19 The ratio of the longitudinal length to the short side length of the first terminal portion 11 is, for example, 0.8 or less, preferably 0.5 or less, and is, for example, 0.001 or more, preferably 0.01 or more. The length of the first auxiliary wiring 19 in the short side direction is the same as the length of the main wiring part 10 in the short side direction.

A plurality of second terminal portions 12 are arranged in the second connecting body 3 at intervals in the short side direction of the printed circuit board 1 corresponding to the plurality of wiring bodies 4 (main wiring portions 10 ). The plurality of second terminal portions 12 are arranged in a row in the short side direction so as to be included in the second connecting metal portion 14 when projected in the thickness direction. The second terminal portion 12 is arranged on the first base surface 24 of the second connecting base portion 17 . The second terminal portion 12 is disposed at the other longitudinal end and the central portion of the first base surface 24 to ensure an area for forming the second auxiliary wiring portion 20 at one longitudinal end of the first base surface 24 . The second terminal portion 12 has a substantially rectangular shape (square pad shape) in plan view.

The second auxiliary wiring part 20 is arranged on the first base surface 24 of the second connection base part 17 in the second connection body 3 so as to be continuous with the second terminal part 12 . The second auxiliary wiring 20 has a substantially linear shape in plan view extending from one end edge in the longitudinal direction of the second terminal portion 12 toward one side in the longitudinal direction. The second auxiliary wiring part 20 connects one longitudinal end edge of the second terminal part 12 and the other longitudinal end edge of the main wiring part 10 to be described next. The length of the second auxiliary wiring portion 20 in the short side direction is shorter than the length of the second terminal portion 12 in the short side direction. The ratio of the short-side length of the second auxiliary wiring part 20 to the short-side length of the second terminal part 12 is, for example, 0.8 or less, preferably 0.5 or less, and is, for example, 0.001 or more, preferably 0.01 or more. The length of the second auxiliary wiring portion 20 in the short side direction is the same as the length of the main wiring portion 10 in the short side direction.

The main wiring portion 10 is arranged on the first base surface 24 of the wiring body base portion 18 . Specifically, each of the plurality of main wiring portions 10 is disposed substantially at the center portion in the lateral direction of the first base surface 24 of the plurality of wiring body base portions 18 . In addition, the main wiring portion 10 is included in the wiring body base portion 18 when projected in the thickness direction. Specifically, each of the plurality of main wiring portions 10 is connected to a plurality of distribution Both ends in the transverse direction of the first base surface 24 of the wire base portion 18 are arranged so as to form a region covering the insulating layer 9 to be described next.

The main wiring part 10 is provided in one-to-one correspondence with the wiring body base part 18 (or the wiring body metal part 15).

In addition, one longitudinal end edge of the main wiring portion 10 is continuous with the other longitudinal end edge of the first auxiliary wiring 19 in the first connecting body 2 . The other longitudinal end edge of the main wiring part 10 is continuous with the one longitudinal end edge of the second auxiliary wiring part 20 in the second connecting body 3 . Thereby, the main wiring part 10 together with the first auxiliary wiring 19 and the second auxiliary wiring part 20 form a substantially linear shape in plan view extending along the length direction, and form the first terminal part 11 and the second terminal part 12 in the length direction. Connect the wiring above.

The length of the main wiring part 10 in the short side direction is, for example, the same as the length of the first auxiliary wiring part 19 and the second auxiliary wiring part 20 in the short side direction.

The conductor layer 8 integrally includes a first conductor surface 27 as one surface in the thickness direction, a second conductor surface 28 as the other surface in the thickness direction, and a conductor side surface 29 as a side surface connecting their peripheral edges in the thickness direction.

The first conductor surface 27 is a flat surface parallel to the first base surface 24 .

The second conductor surface 28 is in contact with the flat surface of the first base surface 24 .

The conductor side surface 29 is arranged inside the base side surface 26 in plan view. In particular, in each of the plurality of wiring bodies 4 , the conductor side surface 29 is arranged inward in the short side direction with respect to the base side surface 26 .

Examples of the material of the conductor layer 8 include copper, silver, gold, iron, aluminum, chromium, and alloys thereof. From the viewpoint of obtaining good electrical characteristics, copper is preferably used.

The thickness of the conductor layer 8 is the opposing length of the first conductor surface 27 and the first base surface 24, and is the thickness direction length of the conductor side surface 29. Specifically, it is, for example, 1 μm or more, preferably 5 μm or more, and, for example, It is 50 μm or less, preferably 3 μm or less.

Moreover, the short side direction length of the main wiring part 10 is, for example, 200 μm or less, preferably 100 μm or less, and is, for example, 1 μm or more, preferably 5 μm or more. In addition, the ratio of the short-side length W of the main wiring portion 10 to the short-side length W of the wiring body metal portion 15 is, for example, 2 or less, preferably 1 or less, and is, for example, 0.01 or more, preferably 0.1 or more.

The cover insulating layer 9 is disposed on the first base surface 24 so as to cover the first conductor surface 27 and the conductor side surface 29 of the first auxiliary wiring 19 , the second auxiliary wiring part 20 and the main wiring part 10 . On the other hand, the covering insulating layer 9 exposes at least the first conductor surface 27 of the first terminal portion 11 and the second terminal portion 12 .

In the cover insulating layer 9, the part included in the first connecting body 2 is the first connecting covering part (not shown in Figs. 1 and 2), and the part included in the second connecting body 3 is the second connecting covering part (Fig. 1 and 2), the portion included in the wiring body 4 is the wiring body covering portion 33.

The first connection covering portion (not shown) exposes the first terminal portion 11 but covers the first auxiliary wiring 19 . Although not shown in the figure, the second connection covering portion exposes the second terminal portion 12 but covers the second auxiliary wiring portion 20 .

The wiring body covering part 33 covers the first conductor surface 27 and the conductor side surface 29 of the main wiring part 10 , as well as the short side outer vicinity part of the main wiring part 10 in the first base surface 24 .

The cover insulating layer 9 integrally includes a first covering surface 34 as one surface in the thickness direction, a second covering surface 35 as the other surface in the thickness direction, and a covering side surface 36 as a side surface connecting their peripheral edges in the thickness direction.

The first covering surface 34 is a flat surface parallel to the first conductor surface 27 .

The second covering surface 35 is in contact with the first conductor surface 27 and the conductor side surface 29 , as well as the first base surface 24 .

The cover side surface 36 is formed in the wiring body base portion 18 so as to be flush with the base side surface 26 in the thickness direction. Furthermore, the covering side surface 36 has a covering inner side surface 38 formed in the same plane as the base inner side surface 37 in the wiring body covering part 33 .

Therefore, each of the plurality of wiring bodies 4 has two wiring body side surfaces 50 . The wiring body side surface 50 is formed (composed) of the metal side surface 23, the base side surface 26, and the cover side surface 36, and is continuous in the thickness direction. Therefore, the wiring body 4 has a substantially linear shape extending long in the thickness direction when viewed in cross section. Furthermore, the wiring body side surface 50 has a wiring inner side surface 51 formed by the metal inner side surface 31 , the base inner side surface 37 and the covering inner side surface 38 when viewed in cross section, and the wiring inner side surface 51 defines the opening 5 .

The thickness of the covering insulating layer 9 is the opposing length of the first covering surface 34 and the first conductor surface 27. Specifically, it is, for example, 1 μm or more, preferably 5 μm or more, and, for example, 100 μm or less, preferably 50 μm or less.

Examples of the material covering the insulating layer 9 include insulating resins such as polyimide.

The thickness of the printed circuit board 1 is, for example, 10 μm or more, preferably 100 μm or more, and is, for example, 10 mm or less, preferably 1 mm or less.

In order to manufacture the printed circuit board 1, for example, first, a flat-plate-shaped metal sheet is prepared, and then, the base insulating layer 7, the conductor layer 8, and the cover insulating layer 9 having the above shapes are sequentially formed. Thereafter, the metal sheet is contoured to form the first connecting metal part 13 , the second connecting metal part 14 and the wiring body metal part 15 , thereby forming the metal support layer 6 . The shape processing is not particularly limited, and examples include etching, laser processing, water jet (water jet), and pressure punching. wait.

Alternatively, the base insulating layer 7, the conductor layer 8, and Cover with insulating layer 9.

As shown by the imaginary line in FIG. 2B , thereafter, the first element 41 is attached to the first coupling body 2 , and the second element 42 is attached to the second coupling body 3 .

The first element 41 and/or the second element 42 are configured to be capable of inputting and outputting a current having a relatively high current value (for example, a large current of 1 A or more, and further 10 A or more). Furthermore, the first element 41 has a first electrode 43 arranged on the other surface in the thickness direction. The second element 42 has a second electrode 44 arranged on the other surface in the thickness direction.

In order to mount the first element 41 on the first terminal part 11, the first electrode 43 and the first terminal part 11 are electrically connected. In order to mount the second element 42 on the second terminal part 12, the second electrode 44 and the second terminal part 12 are electrically connected.

Furthermore, in this printed circuit board 1, since the wiring bodies 4 are arranged in parallel with a distance from each other, it is possible to generate a large current in the main wiring portion 10 based on the input of a large current from the first element 41 and/or the second element 42. The heat is efficiently dissipated through air convection between the plurality of wiring bodies 4 (openings 5), especially convection along the thickness direction.

In addition, since the aspect ratio (T/W) of the wiring body metal portion 15 is as high as 2 or more, the contact area with the air can be increased. Therefore, the heat dissipation efficiency based on the above-mentioned convection is excellent.

Furthermore, since the aspect ratio (T/W) of the wiring body metal part 15 is as high as 2 or more and contains a metal-based material, the heat transferred from the wiring part 10 to the wiring body base part 18 can be directed toward the wiring body base part 18 The other side in the thickness direction, specifically, the other side in the thickness direction from the first metal surface 21 of the wiring body metal portion 15 to the second metal surface 22 and further toward the second metal surface 22 Release efficiently.

Therefore, the wiring body 4 of the printed circuit board 1 has excellent heat dissipation properties.

Furthermore, in this printed circuit board 1, since the material of the wiring body metal part 15 is metal, the heat dissipation property from the wiring body metal part 15 is excellent.

Furthermore, in this printed circuit board 1, since the first connecting metal portion 13 is continuous in the short side direction so as to include a plurality of first terminal portions 11 when projected in the thickness direction, the first connecting metal portion 13 can A plurality of first terminal portions 11 are reliably supported.

Since the second connecting metal part 14 is continuous in the short side direction to include a plurality of second terminal parts 12 when projected in the thickness direction, the second connecting metal part 14 can reliably support the plurality of second terminal parts 12 .

Therefore, in this printed circuit board 1, the wiring body 4 has excellent heat dissipation properties, and the mechanical strength of the first terminal portion 11 in the first connector 2 and the mechanical strength of the second terminal portion 12 in the second connector 3 are also excellent. The strength is also excellent. Therefore, the connection reliability of the first terminal part 11 and the second terminal part 12 is excellent.

The use of this type of printed circuit board 1 is not particularly limited and can be used in various fields. The printed circuit board 1 can be used for various purposes, such as a printed circuit board for electronic equipment (a printed circuit board for electronic components) and a printed circuit board for electrical equipment (a wired circuit board for electrical components). Examples of printed circuit boards for electronic equipment and printed circuit boards for electrical equipment include, for example, sensor printed circuit boards used for sensors such as position information sensors, obstacle detection sensors, and temperature sensors; For example, wiring circuit boards for transportation vehicles such as automobiles, trains, aircraft, and work vehicles; for example, wiring circuit boards for imaging equipment such as flat panel displays, flexible displays, and projection imaging equipment; for example, for Wiring circuit substrates for communication relay equipment such as network equipment and large communication equipment; for example Wiring circuit boards for information processing terminals such as computers, tablets, smart phones, and home game consoles; for example, wiring circuit boards for movable equipment such as drones and robots; for example, for movable equipment such as drones and robots. Wiring circuit boards for medical equipment such as wearable medical devices and medical diagnostic devices; for example, wiring circuit boards for electrical equipment used in electrical equipment such as refrigerators, washing machines, vacuum cleaners, and air conditioners; for example, used in digital cameras, DVDs (Digital Versatile Disc, Digital Versatile Disc) video equipment and other video electronic equipment, wiring circuit boards for video electronic equipment, etc.

Variations

In each of the following modification examples, the same components and steps as those in the above-mentioned embodiment are denoted by the same reference numerals, and detailed descriptions thereof are omitted. In addition, each modification example can exhibit the same function and effect as the first embodiment unless otherwise stated. Furthermore, an embodiment and a modified example can be combined appropriately.

As shown in FIG. 2A , in one embodiment, the metal side surface 23 , the base side surface 26 and the covering side surface 36 are the same surface. Although not shown in the figure, they may not be the same surface, that is, they may not be continuous. Although not shown in the figure, for example, the base side surface 26 and/or the cover side surface 36 may not overlap the metal side surface 23 when projected in the thickness direction, but may be oriented either outward or inward in the short direction with respect to the metal side surface 23 . offset and positioned.

As shown in FIG. 2A , in one embodiment, the metal side surface 23 of the wiring body metal part 15 is a flat surface. Although not shown in the figure, it may also be a curved surface, for example.

Although not shown in the figure, in this variation, the curved metal side surface has a concave surface that is dented inward in the short side direction from both ends in the thickness direction toward the center in the thickness direction when viewed in cross section.

Preferably, the metal side has only concave surfaces. That is to say, when the metal side is viewed in cross-section, as the It is recessed from both end portions in the thickness direction toward the center portion in the thickness direction and inward in the short side direction. Thereby, the length of the wiring body metal portion in the transversal direction becomes shorter from both ends in the thickness direction toward the center portion in the thickness direction. Each of the plurality of wiring body metal portions has a substantially drum (hourglass) shape in cross section with a central portion tapering in the thickness direction. In each of the plurality of wiring body metal portions, two concave surfaces are provided on both sides in the transverse direction.

The area S0 of the metal side surface is larger than the projected area S1 when the metal side surface is projected in the short side direction. Therefore, the present invention includes an aspect in which the area S0 of the metal side surface is larger than the projected area S1 when the metal side surface is projected in the short-side direction. Specifically, it includes an aspect in which the area S0 of the metal side surface 23 is the same as the projected area S1 of the metal side surface 23 . Both an embodiment and a variation in which the area S0 of the metal side surface is larger than the projected area S1 of the metal side surface.

In this variation, specifically, the area ratio (S0/S1) of the area S0 of the metal side surface relative to the projected area S1 is, for example, 1.01 or more, preferably 1.1 or more, more preferably 1.2 or more, and still more preferably 1.3. The above is also, for example, 2 or less.

Furthermore, the above-mentioned area ratio (S0/S1) is because the longitudinal length of the metal side surface is the same as the longitudinal length of the projection surface of the metal side surface. Therefore, it is different from the thickness T of the metal support layer 6 (specifically, the metal support layer 6) when viewed in cross section. The distance in the thickness direction of the side surface from one end edge to the other end edge in the thickness direction) relative to the length L of the extension length L of the metal side surface from one end edge to the other end edge in the thickness direction along the curved surface (concave surface) (thickness T/extension length L )same. Therefore, the area ratio (S0/S1) is found as the above-mentioned length ratio (thickness T/extension length L).

Furthermore, in the above modification example, the short-side direction length W of the wiring body metal portion is calculated as the average value of the lengths between the two metal side surfaces.

Furthermore, although not shown in the figure, in this variation, the metal side surface may have a buckling surface. In this case, one metal side surface is integrally provided with two concave surfaces adjacent in the thickness direction, And make it equal to the connected ridges in the thickness direction. Thereby, the metal side surface is formed into a buckling surface. Specifically, one metal side surface has a substantially W-shaped shape having a ridge at the center in the thickness direction and concave surfaces on both sides when viewed in cross section. Therefore, each of the plurality of wiring body metal portions has a cross-sectional shape like two drums (hourglasses) connected in the thickness direction.

The manufacturing method of the printed circuit board in the said modification example is demonstrated concretely. In this manufacturing method, the metal-based support layer 6 is formed by etching (subtractive method), for example.

Specifically, first, a laminate including a metal sheet and a base insulating layer, a conductor layer, and a cover insulating layer formed on the first metal surface (see FIGS. 2A and 2B ) is prepared.

Then, the etching resist is disposed on the second metal surface of the metal sheet. The plan view shape of the etching resist is, for example, the same shape as the plan view shape of the metal-based support layer 6 to be formed, and is substantially the same as the plan view shape of the base insulating layer and the cover insulating layer.

Thereby, a resist laminated body including a laminated body and an etching resist is produced.

Thereafter, the resist laminate is immersed in the etching liquid. Specifically, the etching liquid is brought into contact with the first metal surface exposed from the base insulating layer and the covering insulating layer and the second metal surface exposed from the etching resist in the metal sheet.

Therefore, in the exposed portion of the second metal surface exposed from the etching resist, the etching speed of the central portion in the short-side direction is higher than the etching speed of the both end portions in the short-side direction (which is outside the second metal surface in the short-side direction). The etching speed is higher. The reason for this is that the etching liquid is more likely to remain (stagnate) at both ends of the exposed portion in the transverse direction than at the peripheral portion in the transverse direction.

This situation is also the same for the exposed portion of the first metal surface that is exposed from the base insulating layer. Furthermore, both the first metal surface and the second metal surface in the middle of the etching become curved surfaces with the central portion in the short side direction being recessed toward the inside in the thickness direction.

Therefore, in the short side direction of the exposed portions of the first metal surface and the second metal surface The etching of the central part is completed earlier than the etching of the two ends in the shorter side direction. Therefore, in the central portion in the transverse direction, the first metal surface and the second metal surface disappear earlier than at both end portions in the transverse direction. That is, first, the opening is formed in the center part in the transverse direction, and then the opening expands toward both outer sides (both ends) in the transverse direction.

As a result, a metal side surface with two concave surfaces and ridges is formed. At this time, if the etching is completed and the etching resist is removed, a printed circuit board having a modification of the ridge line (having a wiring body metal portion in a shape of connecting two drums) can be obtained.

On the other hand, if the etching is further continued, the ridge lines disappear, and therefore a metal side surface having no ridge lines but a concave surface is formed. If the etching resist is subsequently removed, a printed circuit board of the modified example (a wiring body metal portion having a substantially drum-shaped cross section) can be obtained.

In the printed circuit board of these modifications, the area S0 of the metal side surface is larger than the projected area S1 when the metal side surface is projected in the short side direction.

Therefore, the printed circuit board includes both an embodiment in which the area S0 of the metal side surface 23 and the projected area S1 of the metal side surface 23 are the same (see FIG. 2A ), and a modified example in which the area S0 of the metal side surface is larger than the projected area S1 of the metal side surface. (That is, a printed circuit board in which the area S0 of the metal side surface 23 is larger than the projected area S1 of the metal side surface 23) can reliably increase the contact area between the metal side surface and the air. Therefore, the heat dissipation efficiency based on convection of the metal portion of the self-wiring body is more excellent.

In particular, in these modifications, compared with the embodiment shown in FIG. 2A , the contact area between the metal side surface and the air can be increased more reliably. Therefore, the heat dissipation efficiency based on convection of the metal portion of the self-wiring body is more excellent.

Furthermore, in a modified example, one metal side surface has a concave surface and a convex surface integrally. The concave surface and the convex surface are arranged sequentially in the thickness direction.

Although not shown in the figure, in this variation, in one wiring body metal portion, the short side The concave surface on one side is opposite to the convex surface on the other side in the short side direction, and the convex surface on one side of the short side direction is opposite to the concave surface on the other side in the short side direction. Therefore, the wiring body metal portion has a substantially S-shaped cross section.

Although not shown in the figure, in one wiring body metal part, two concave surfaces on both sides of one side and the other side in the short side direction are opposed to each other in the short side direction. The two convex surfaces on one side and the other side in the short side direction are opposite to each other in the short side direction.

In one embodiment, the wiring body metal part 15 is exemplified as an example of the supporting part, and the wiring body metal part 15 is included in the metal-based supporting layer 6 whose material is metal. However, the metal-based support layer 6 may be replaced by a support layer. The material of the support layer may be, for example, a particle resin composition containing particles with high thermal conductivity and resin, or a fired composition such as ceramics.

In one embodiment, both the first connecting body 2 and the second connecting body 3 are continuous in the short side direction so as to include the first terminal part 11 and the second terminal part 12 in plan view. Although not shown in the figure, for example Either one may be continuous in the short side direction, and the other may be discontinuous in the short side direction. In this case, the other one is divided into plural pieces at intervals in the short side direction and arranged. Furthermore, although not shown in the figure, for example, either the first connecting body 2 or the second connecting body 3 may be divided into a plurality of pieces at intervals in the short side direction.

In one embodiment, one main wiring portion 10 is provided on the wiring body base portion 18. For example, although not shown in the figure, a plurality of main wiring portions 10 may be provided on one wiring body base portion 18.

In addition, the above-mentioned invention is provided as an illustrative embodiment of the present invention, but it is only an example and is not to be construed restrictively. Modifications of the present invention that are clear to those skilled in the art are included in the scope of the following claims.

[Industrial availability]

Wired circuit boards can be used as wiring circuit boards for electronic equipment and electrical equipment. Used in various applications such as printed circuit boards.

1‧‧‧Wired circuit board

2‧‧‧1st connection

3‧‧‧Second connection

5‧‧‧Opening part

6‧‧‧Metal support layer

7‧‧‧Base insulation layer

8‧‧‧Conductor layer

9‧‧‧Covering insulation layer

10‧‧‧Main wiring section

11‧‧‧1st terminal section

12‧‧‧Second terminal section

13‧‧‧1st connecting metal part

14‧‧‧Second connecting metal part

15‧‧‧Wiring body metal part

16‧‧‧1st connection base

17‧‧‧Second connection base

18‧‧‧Wiring body base

21‧‧‧1st metal surface

22‧‧‧Second metal surface

23‧‧‧Metal side

24‧‧‧1st basal surface

25‧‧‧Second basal surface

26‧‧‧Basal side

27‧‧‧1st conductor surface

28‧‧‧2nd conductor surface

29‧‧‧Conductor side

31‧‧‧Metal inner side

32‧‧‧Metal outer side

33‧‧‧Wiring body covering part

34‧‧‧1st Coverage

35‧‧‧Second Coverage

36‧‧‧Cover the sides

37‧‧‧Basilar medial surface

38‧‧‧covers the inner side

41‧‧‧Component 1

42‧‧‧Part 2

43‧‧‧1st electrode

44‧‧‧2nd electrode

50‧‧‧Wiring body side

51‧‧‧Inner side of wiring

T‧‧‧Thickness

W‧‧‧Length

Claims (4)

A printed circuit board, characterized in that it is provided with a plurality of wiring bodies spaced apart from each other and arranged in parallel, and each of the plurality of wiring bodies is provided with: a wiring body base portion; and a main wiring portion arranged on the wiring body base. One side in the thickness direction of the portion; the supporting portion, which is disposed on the other side in the thickness direction of the wiring body base portion, consists of a metal-based material, and the ratio of the length T in the thickness direction to the length W in the parallel direction of the plurality of wiring bodies is ( T/W) is 2 or more; and a wiring body covering part is arranged on one side of the wiring body base in the thickness direction so as to cover all of one side in the thickness direction of the main wiring part and all of its side surfaces. The printed circuit board according to claim 1, wherein one of the above-mentioned supporting parts has a side surface facing the other of the above-mentioned supporting parts adjacent to one of the above-mentioned supporting parts in the above-mentioned parallel direction, and the area of the above-mentioned side surface is the projection of the above-mentioned side surface in the above-mentioned parallel direction. above the projected area. The printed circuit board of claim 1 or 2, wherein the material of the supporting portion is metal. The printed circuit board according to claim 1 or 2 is provided with a connector that connects ends of the plurality of wiring bodies in an orthogonal direction that is orthogonal to the parallel direction and the thickness direction, and the connector includes: The terminal portion is continuous with the end portion in the orthogonal direction of the above-mentioned main wiring portion; and the connection support portion is continuous with the end portion in the orthogonal direction of the above-mentioned support portion; and the above-mentioned connection support portion includes plural numbers when projected in the thickness direction. The above-mentioned terminal portions are continuous in the above-mentioned parallel direction.