CN215581867U - Circuit board - Google Patents
Circuit board Download PDFInfo
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- CN215581867U CN215581867U CN202121553069.9U CN202121553069U CN215581867U CN 215581867 U CN215581867 U CN 215581867U CN 202121553069 U CN202121553069 U CN 202121553069U CN 215581867 U CN215581867 U CN 215581867U
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Abstract
The utility model relates to the technical field of circuit board manufacturing, in particular to a circuit board, which comprises: the first sub-board comprises at least two core boards which are sequentially stacked, a first medium layer is arranged between every two adjacent core boards, and a groove is formed in the first sub-board; the second sub-board is stacked on the first sub-board, a first outer copper layer is arranged on one surface, far away from the first sub-board, of the second sub-board, and a first connecting hole is formed in the second sub-board; the radiating ceramic block is arranged inside the groove and connected with the first sub-board through a first dielectric layer, and a first inner copper layer is arranged on one surface, close to the second sub-board, of the radiating ceramic block; the first connecting copper is used for conducting the first outer copper layer and the first inner copper layer; and the milling control groove is arranged on one surface of the first sub-board far away from the second sub-board or one surface of the second sub-board far away from the first sub-board. The utility model improves the heat dissipation effect and the service life of the circuit board, and simultaneously ensures that the circuit board has certain flexibility.
Description
Technical Field
The utility model relates to the technical field of circuit board manufacturing, in particular to a circuit board.
Background
With the continuous development of the electronic communication industry and vehicle-mounted electronics, the requirements of related circuit board products are higher and higher, and the requirements of the heat dissipation performance of the products are higher and higher while the products tend to be miniaturized and multifunctional. The existing circuit board has poor heat dissipation performance, so that the service life of the existing circuit board is limited.
SUMMERY OF THE UTILITY MODEL
The utility model provides a circuit board, which aims to improve the heat dissipation effect and prolong the service life of the circuit board.
The embodiment of the application provides a circuit board, including:
the first daughter board comprises at least two core boards which are sequentially stacked, a first medium layer is arranged between every two adjacent core boards, and a groove penetrating through the first daughter board is formed in the first daughter board;
the second sub-board is stacked on the first sub-board, a first outer copper layer is arranged on one surface, far away from the first sub-board, of the second sub-board, and a first connecting hole communicated with the groove is formed in the second sub-board;
the heat dissipation ceramic block is arranged inside the groove and connected with the first sub-board through the first dielectric layer, and a first inner copper layer is arranged on one surface, close to the second sub-board, of the heat dissipation ceramic block;
the first connecting copper is arranged in the first connecting hole and conducts the first outer copper layer and the first inner copper layer; and
and the milling control groove is arranged on one surface of the first sub-board far away from the second sub-board or one surface of the second sub-board far away from the first sub-board.
In some embodiments, the second sub-board includes a first copper foil and a second dielectric layer stacked in sequence, and the second dielectric layer is located between the first copper foil and the first sub-board.
In some embodiments, the milling control groove is disposed on a side of the first sub-board away from the second sub-board, and a bottom of the milling control groove extends to the second dielectric layer.
In some embodiments, the first sub-board further includes a first FPC flexible board, which is stacked between two adjacent core boards and connected to the core boards through the first dielectric layer.
In some embodiments, the second sub-board includes a second FPC flexible board and a third dielectric layer, which are stacked in sequence, and the third dielectric layer is located between the second FPC flexible board and the first sub-board.
In some embodiments, the milling control groove is disposed on a side of the first sub-board away from the second sub-board, and a bottom of the milling control groove extends to the third dielectric layer.
In some embodiments, the circuit board further includes a third sub-board, the third sub-board includes a second copper foil and a fourth dielectric layer, which are sequentially stacked, the third sub-board is stacked on a side of the first sub-board away from the first sub-board, and the fourth dielectric layer is located between the second copper foil and the first sub-board;
the radiating ceramic block is provided with a second inner copper layer on one surface far away from the second sub-board, a second outer copper layer is arranged on one surface far away from the second sub-board, a second connecting hole communicated with the groove is formed in the third sub-board, second connecting copper is arranged in the second connecting hole, and the second connecting copper conducts the second outer copper layer and the second inner copper layer.
In some of these embodiments, a mesh wire or a thermally conductive PAD is disposed on the first inner copper layer and a mesh wire or a thermally conductive PAD is disposed on the second inner copper layer.
In some of these embodiments, the thickness of the heat spreading ceramic block is the same as the thickness of the first sub-plate.
In some embodiments, the milling control groove is formed on one surface of the first sub-board far away from the second sub-board and one surface of the second sub-board far away from the first sub-board.
The circuit board provided by the embodiment of the utility model has the beneficial effects that: through set up the heat dissipation ceramic piece in the circuit board of range upon range of setting to switch on the first outer copper layer on with the circuit board and the first interior copper layer on the heat dissipation ceramic piece, improved the radiating effect and the life of circuit board, set up accuse milling flutes on the circuit board simultaneously, ensure that the circuit board has certain flexibility, guarantee that it satisfies the operation requirement.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.
FIG. 1 is a schematic structural diagram of a wiring board according to a first embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a wiring board according to a second embodiment of the present invention;
FIG. 3 is a schematic structural diagram of a wiring board according to a third embodiment of the present invention;
FIG. 4 is a schematic structural diagram of a wiring board according to a fourth embodiment of the present invention;
fig. 5 is a schematic structural diagram of a circuit board in a fifth embodiment of the present invention.
The designations in the figures mean:
10. a first sub-board; 11. a first core board; 12. a second core board; 13. a first dielectric layer; 14. a groove; 15. a first FPC flexible board; 20. a second sub-board; 21. a first outer copper layer; 22. a first connection hole; 23. a first copper foil; 24. a second dielectric layer; 25. a second FPC flexible board; 26. a third dielectric layer; 30. a heat-dissipating ceramic block; 31. a first inner copper layer; 32. a second inner copper layer; 41. a first connection copper; 42. a second connection copper; 50. controlling milling of a groove; 60. a third sub-board; 61. a second outer copper layer; 66. a second connection hole; 63. a second copper foil; 64. and a fourth dielectric layer.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail below with reference to the accompanying drawings, which are examples. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and are not intended to limit the utility model.
It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In order to explain the technical solution of the present invention, the following description is made with reference to the specific drawings and examples.
Referring to fig. 1, a first embodiment of the present invention provides a circuit board, which includes a first sub-board 10, a second sub-board 20, a heat dissipation ceramic block 30, a first connection copper 41, and a milling control slot 50.
The first sub-board 10 includes at least two core boards stacked in sequence, and the number of the core boards may be 2, 3, 4 or more.
In an embodiment, for example, when the first sub-board 10 includes two core boards that are stacked in sequence, the two core boards are the first core board 11 and the second core board 12, respectively.
The first core board 11 is positioned at the bottommost layer of the circuit board, wherein the first core board 11 is composed of a dielectric layer and a copper layer, the dielectric layer is etched to remove single-sided copper, the etched surface is the top layer of the first core board 11, and the unetched surface is the copper layer on which circuits are distributed; the second core board 12 is composed of an upper copper layer, a dielectric layer and a lower copper layer, and circuits are distributed on the upper copper layer and the lower copper layer.
The production process of the first core plate 11 may comprise the steps of:
firstly, cutting: cutting the first core plate 11 according to the design size;
secondly, sticking a protective film on one side: protecting the copper layer surface of the unetched surface by using an anti-etching protective film;
then etching away single-side copper: etching the single-sided copper of the non-film-pasted surface to expose the base material;
and then drilling: drilling riveting holes and positioning holes;
the next step is inner layer wiring: manufacturing a circuit on the non-etched surface;
finally, milling a groove; milling a first groove for embedding the heat dissipation ceramic block 30, so that the groove 14 is formed after the subsequent first core plate 11 and the second core plate 12 are pressed together.
The second core board 12 is composed of an upper copper layer, a dielectric layer and a lower copper layer, and circuits are distributed on the upper copper layer and the lower copper layer.
The production process of the first core plate 11 may comprise the steps of:
firstly, cutting: cutting the second core plate 12 according to the design size;
and secondly, drilling: drilling riveting holes and positioning holes;
next is the inner layer circuit: manufacturing a circuit on the lower copper layer;
finally, milling a groove; and milling a second groove embedded with the heat dissipation ceramic block 30, so that the groove 14 is formed by the first groove and the second groove after the subsequent pressing of the first core plate 11 and the second core plate 12.
A first medium layer 13 is arranged between two adjacent core plates.
Optionally, the first dielectric layer 13 is set as a prepreg, which may be a conventional prepreg or a high thermal conductivity prepreg.
The first core board 11, the prepreg, and the second core board 12 may be pre-stacked and riveted to obtain the first daughter board 10, wherein the second core board 12 is manufactured with a lower copper layer with a circuit attached to the prepreg, and an upper copper layer without a circuit is placed outward, and then the upper copper layer of the second core board 12 is attached to a high temperature resistant protective film.
The first sub-board 10 is provided with a groove 14 penetrating through the first sub-board 10 for placing the heat dissipation ceramic block 30, and one, two or more grooves 14 may be provided, and the number of the grooves is not limited.
In order to facilitate the placement of the heat dissipating ceramic block 30, the size of the groove 14 is 0.4mm larger than the size of the heat dissipating ceramic block 30 as a whole.
The second daughter board 20 is stacked on the first daughter board 10, a first outer copper layer 21 is disposed on one surface of the second daughter board 20 away from the first daughter board 10, a first connection hole 22 communicated with the groove 14 is disposed on the second daughter board 20, and the first connection hole 22 can be processed by laser, machining or other methods.
The heat dissipation ceramic block 30 is arranged inside the groove 14 and connected with the first sub-board 10 through the first dielectric layer 13, and a first inner copper layer 31 is arranged on one surface, close to the second sub-board 20, of the heat dissipation ceramic block 30.
In the production process, the heat dissipation ceramic block 30 can be firstly embedded into the first sub-board 10 from the notch of the groove 14, wherein one surface of the heat dissipation ceramic block 30, which is close to the second sub-board 20, is provided with a first inner copper layer 31, then the first sub-board 10 with the high heat dissipation ceramic block 30 embedded in the second sub-board 20 is pre-stacked and then pressed, the heat dissipation ceramic block 30 is inserted into the first sub-board 10 through pressing, but not inserted into the second sub-board 20, and a semi-embedded structure is formed after pressing. The protective film can be attached to the surface of the first sub-board 10 without the circuit, so that glue overflow can be effectively prevented. The heat dissipation ceramic block 30 is made of ceramic, one surface of the heat dissipation ceramic block close to the second daughter board 20 is provided with a first inner copper layer 31 and a titanium layer, the titanium layer is arranged between the ceramic and the first inner copper layer 31, and the first inner copper layer 31 can be distributed with a plurality of network lines according to design requirements.
The first connecting copper 41 is disposed in the first connecting hole 22 and connects the first outer copper layer 21 and the first inner copper layer 31, so as to improve the heat dissipation effect of the ceramic block.
The milling control groove 50 is arranged on one surface of the first sub-board 10 far away from the second sub-board 20 or one surface of the second sub-board 20 far away from the first sub-board 10, the milling control groove 50 can be manufactured by mechanical depth control milling or laser depth control milling or a combination mode of the two, and the milling control groove 50 enables the circuit board to have a bending function.
Alternatively, 1, 2, 3, 4 or more milling control grooves 50 may be provided.
According to the design requirements of products, depth control milling can be carried out from the first sub-board 10 to the opposite side to obtain a depth control milling groove 50, the depth control depth is larger than that of the first sub-board 10, the reserved thickness of a circuit board at the bottom of the depth control milling groove 50 is smaller than that of the second sub-board 20 and larger than that of the first outer copper layer 21 of the second sub-board 20, and optionally, the residual thickness can be controlled by 0.15mm-0.25mm, such as 0.15mm, 0.18mm, 0.20mm, 0.12mm or 0.25 mm.
According to the design requirement of a product, depth control milling can be carried out from the second sub-board 20 to the opposite side to obtain a depth control milling groove 50, the depth control depth is larger than that of the second sub-board 20, the reserved thickness of a circuit board at the bottom of the depth control milling groove 50 is smaller than that of the first sub-board 10 and larger than a copper layer on the first sub-board 10, the area of the second sub-board 20 is milled by a depth control milling method, and the residual thickness can be controlled according to the standard of 0.15mm-0.25mm, such as 0.15mm, 0.18mm, 0.20mm, 0.12mm or 0.25 mm.
According to the circuit board provided by the embodiment of the utility model, the heat dissipation ceramic block 30 is arranged in the laminated circuit board, the first outer copper layer 21 on the circuit board is conducted with the first inner copper layer 31 on the heat dissipation ceramic block 30, the heat dissipation effect of the circuit board is improved, the service life of the circuit board is prolonged, and meanwhile, the milling control groove 50 is arranged on the circuit board, so that the circuit board is ensured to have certain flexibility, and the circuit board is ensured to meet the use requirement.
Referring to fig. 2, in the second embodiment, the second sub-board 20 includes a first copper foil 23 and a second dielectric layer 24 stacked in sequence, and the second dielectric layer 24 is located between the first copper foil 23 and the first sub-board 10. By adopting the scheme, the circuit board has certain rigidity and flexibility, so that the circuit board can meet the use requirements of specific occasions.
Referring again to fig. 2, in some embodiments, the milling control groove 50 is disposed on a side of the first sub-board 10 away from the second sub-board 20 and extends to the bottom of the second dielectric layer 24.
By adopting the above scheme, the milling control groove 50 is convenient to process, and does not affect the outer layer circuit arranged on the first copper foil 23.
Referring to fig. 3, in the third embodiment, the first sub-board 10 further includes a first FPC flexible board 15, and the first FPC flexible board 15 is stacked between two adjacent core boards and connected to the core boards through the first dielectric layer 13.
By adopting the scheme, the circuit board has the characteristic of rigid-flexible combination, so that the circuit board can meet the use requirement on specific occasions.
Optionally, the first dielectric layer 13 is disposed between the first FPC flexible board 15 and two adjacent core boards, or an additional dielectric layer is disposed between the FPC flexible board and two adjacent core boards, so that the first FPC flexible board 15 is connected to the two adjacent core boards.
Referring to fig. 4, in the fourth embodiment, the second sub-board 20 includes a second FPC flexible board and a third dielectric layer 26, which are sequentially stacked, and the third dielectric layer 26 is located between the second FPC flexible board and the first sub-board 10.
By adopting the scheme, the circuit board has the characteristic of rigid-flexible combination, so that the circuit board can meet the use requirement on specific occasions.
Referring again to fig. 4, in some embodiments, the milling control groove 50 is disposed on a side of the first sub-board 10 away from the second sub-board 20 and extends to the bottom of the third dielectric layer 26.
By adopting the scheme, the milling control groove 50 is convenient to process, and the outer layer circuit arranged on the second FPC flexible board is not influenced.
Referring to fig. 5, in the fifth embodiment, the circuit board further includes a third sub-board 60, the third sub-board 60 includes a second copper foil 63 and a fourth dielectric layer 64 which are sequentially stacked, the third sub-board 60 is stacked on a side of the first sub-board 10 away from the second sub-board 20, and the fourth dielectric layer 64 is located between the second copper foil 63 and the first sub-board 10; a second inner copper layer 32 is arranged on one surface, away from the second sub-board 20, of the heat dissipation ceramic block 30, a second outer copper layer 61 is arranged on one surface, away from the second sub-board 20, of the third sub-board 60, a second connecting hole 66 communicated with the groove 14 is arranged on the third sub-board 60, second connecting copper 42 is arranged in the second connecting hole 66, and the second outer copper layer 61 is communicated with the second inner copper layer 32 through the second connecting copper 42.
By adopting the above scheme, the heat dissipation ceramic block 30 can be conducted with the first copper foil 23 and the second copper foil 63, so that an excellent heat dissipation effect is realized, and the surfaces of the second outer copper layer 61 and the heat dissipation ceramic block 30 far away from the second sub-board 20 can be designed into a circuit with higher precision.
Referring again to fig. 5, in some embodiments, the first inner copper layer 31 is provided with a mesh circuit or a heat conducting PAD, and the second inner copper layer 32 is provided with a mesh circuit or a heat conducting PAD.
By adopting the above scheme, the heat dissipation ceramic block 30 can be conducted with the first copper foil 23 and the second copper foil 63, so that an excellent heat dissipation effect is realized, and the surfaces of the second outer copper layer 61 and the heat dissipation ceramic block 30 far away from the second sub-board 20 can be designed into a circuit with higher precision.
Referring to fig. 1, in some embodiments, the heat dissipation ceramic block 30 has a thickness equal to that of the first sub-board 10.
By adopting the above scheme, after the heat dissipation ceramic block 30 is pressed into the groove 14, the heat dissipation ceramic block 30 protrudes out of the first sub-board 10, so that subsequent circuit manufacturing on the heat dissipation ceramic block 30 and the first sub-board 10 is not facilitated. Referring to fig. 1, in some embodiments, the milling control groove 50 is disposed on both a side of the first sub-board 10 away from the second sub-board 20 and a side of the second sub-board 20 away from the first sub-board 10.
By adopting the scheme, the semi-rigid-flex area which can be flexed in different directions can be formed on the circuit board, so that the flexibility of the circuit board is improved.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present invention, and are intended to be included within the scope of the present invention.
Claims (10)
1. A circuit board, comprising:
the first daughter board comprises at least two core boards which are sequentially stacked, a first medium layer is arranged between every two adjacent core boards, and a groove penetrating through the first daughter board is formed in the first daughter board;
the second sub-board is stacked on the first sub-board, a first outer copper layer is arranged on one surface, far away from the first sub-board, of the second sub-board, and a first connecting hole communicated with the groove is formed in the second sub-board;
the heat dissipation ceramic block is arranged inside the groove and connected with the first sub-board through the first dielectric layer, and a first inner copper layer is arranged on one surface, close to the second sub-board, of the heat dissipation ceramic block;
the first connecting copper is arranged in the first connecting hole and conducts the first outer copper layer and the first inner copper layer; and
and the milling control groove is arranged on one surface of the first sub-board far away from the second sub-board or one surface of the second sub-board far away from the first sub-board.
2. The wiring board of claim 1, wherein the second sub-board comprises a first copper foil and a second dielectric layer stacked in sequence, the second dielectric layer being located between the first copper foil and the first sub-board.
3. The wiring board of claim 2, wherein the slot is disposed on a side of the first sub-board away from the second sub-board and a bottom portion of the slot extends to the second dielectric layer.
4. The circuit board of claim 2, wherein the first sub-board further comprises a first FPC flexible board, and the first FPC flexible board is stacked between two adjacent core boards and connected with the core boards through the first dielectric layer.
5. The wiring board of claim 1, wherein the second sub-board comprises a second FPC flexible board and a third dielectric layer, which are stacked in sequence, and the third dielectric layer is located between the second FPC flexible board and the first sub-board.
6. The wiring board of claim 5, wherein the slot is disposed on a side of the first sub-board away from the second sub-board and a bottom portion of the slot extends to the third dielectric layer.
7. The circuit board according to any one of claims 1 to 6, further comprising a third sub-board, wherein the third sub-board comprises a second copper foil and a fourth dielectric layer which are sequentially stacked, the third sub-board is stacked on one side of the first sub-board far away from the second sub-board, and the fourth dielectric layer is located between the second copper foil and the first sub-board;
the radiating ceramic block is provided with a second inner copper layer on one surface far away from the second sub-board, a second outer copper layer is arranged on one surface far away from the second sub-board, a second connecting hole communicated with the groove is formed in the third sub-board, second connecting copper is arranged in the second connecting hole, and the second connecting copper conducts the second outer copper layer and the second inner copper layer.
8. The wiring board defined in claim 7, wherein the first inner copper layer has a grid pattern or thermally conductive PAD disposed thereon, and the second inner copper layer has a grid pattern or thermally conductive PAD disposed thereon.
9. The wiring board of claim 1, wherein the heat dissipating ceramic block has a thickness that is the same as a thickness of the first sub-board.
10. The wiring board of claim 1, wherein the slot is disposed on both a side of the first sub-board away from the second sub-board and a side of the second sub-board away from the first sub-board.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121553069.9U CN215581867U (en) | 2021-07-08 | 2021-07-08 | Circuit board |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121553069.9U CN215581867U (en) | 2021-07-08 | 2021-07-08 | Circuit board |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215581867U true CN215581867U (en) | 2022-01-18 |
Family
ID=79824505
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121553069.9U Active CN215581867U (en) | 2021-07-08 | 2021-07-08 | Circuit board |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215581867U (en) |
-
2021
- 2021-07-08 CN CN202121553069.9U patent/CN215581867U/en active Active
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