CN223080198U

CN223080198U - Multilayer PCB board

Info

Publication number: CN223080198U
Application number: CN202421807311.4U
Authority: CN
Inventors: 杜朝府; 陈兴武; 谢明运; 王翠演
Original assignee: Guangzhou Guanghe Technology Co Ltd
Current assignee: Guangzhou Guanghe Technology Co Ltd
Priority date: 2024-07-29
Filing date: 2024-07-29
Publication date: 2025-07-08
Anticipated expiration: 2034-07-29

Abstract

The utility model provides a multilayer PCB board, which relates to the technical field of circuit board manufacture, and comprises that each layer of PCB board is provided with a heat conducting block, and the heat conducting blocks are internally provided with heat melting modules for conducting heat, the heat melting modules occupy partial areas of the heat conducting blocks, and projections of adjacent heat melting modules on the heat conducting blocks are not overlapped. The hot melting module only covers a partial area of the heat conducting area, and the projections of the adjacent hot melting modules on the heat conducting area are not overlapped, so that the total thickness of the hot melting module in the heat conducting area is effectively reduced. Through setting up heat conduction block and hot melt die piece, can effectively improve the heating efficiency and the homogeneity of hot melt adhesive, can effectually reduce the hot melt module total thickness of heat conduction block department, improve the PCB board and plate thickness inhomogeneous and warp scheduling problem that appear in the thermocompression bonding process, improve the production quality of PCB board.

Description

Multilayer PCB board

Technical Field

The utility model relates to the technical field of circuit board manufacturing, in particular to a multilayer PCB.

Background

In the manufacturing process of the multilayer PCB, the hot pressing process is a key step of bonding the multilayer core boards together through hot melt adhesives to form an integral structure. The thermal compression process typically uses thermal frit to conduct heat to heat and melt the hot melt adhesive to achieve bonding between the PCB core boards.

However, the conventional thermal compression process has a problem in that thermal stress is easily generated due to melting and rapid cooling of the thermal frit at high temperature, resulting in warp deformation of the thermal frit. Warping of the thermal frit can lead to uneven surfaces of the pressed PCB, affect subsequent processing techniques, and even lead to waste reporting of the PCB. Because the shape and the size design of the hot melt block are unreasonable, the hot melt adhesive is easy to accumulate uneven in the hot melt process, so that the thickness of the pressed PCB is uneven, and the performance and the reliability of the PCB are affected. The hot melt adhesive has strong fluidity, and copper wrinkles are easily formed around the hot melt adhesive, so that the circuit integrity and signal transmission of the PCB are affected.

In order to solve the above-mentioned problems, a hot-melt auxiliary structure in a PCB core board is disclosed in chinese patent document CN218570566U, which includes a grid-like copper deposition area and a hot-melt auxiliary structure of a pad. Chinese patent document CN219698061U discloses a heat fusion module, which includes a first heat fusion portion and a second heat fusion portion, between which a gap is provided.

However, the solution disclosed in the above patent document, although it can be partially solved, is that the temperature at the heat-fusible pattern block is high during hot pressing, the temperature rise is fast, and small bubbles are generated during the curing of the PP resin at the heat-fusible pattern block, so that the heat-fusible pattern block is excessively raised, and the plate thickness is uneven.

Therefore, improvements to existing multi-layer PCB boards are needed to overcome the shortcomings of the prior art.

Disclosure of utility model

In order to overcome the problems in the related art, the utility model aims to provide a multilayer PCB board so as to solve the problem of uneven board thickness caused by the use of a thermal melting block in the prior art.

A multi-layer PCB board comprising:

Each layer of PCB board all is equipped with the heat conduction block, all be equipped with the heat fusion mould piece that is used for the heat conduction in the heat conduction block, the heat fusion mould piece accounts for the regional of heat conduction block, adjacent the heat fusion mould piece is on the projection misalignment on the heat conduction block.

The heat conducting blocks are arranged between each layer of the PCB, the hot melting modules are arranged in the heat conducting blocks, projections of adjacent hot melting modules on the heat conducting blocks are not overlapped, heat can be effectively transferred to the hot melting adhesive, melting and solidifying processes are accelerated, and meanwhile, the total thickness of the hot melting modules at the heat conducting blocks can be effectively reduced, so that the problem of uneven plate thickness is solved, and the production quality of the PCB is improved.

Preferably, the heat conducting block is rectangular, and the heat melting blocks are distributed along the length direction or the width direction of the heat conducting block.

The heat conducting block is designed into a rectangle, and the heat melting blocks are distributed along the length direction or the width direction, so that the arrangement of the heat melting blocks can be facilitated, the flow of the hot melt adhesive is facilitated, the uniformity of the hot melt adhesive is improved, the phenomenon that the surface of the PCB is uneven after lamination is reduced, and the quality and the reliability of the PCB are improved.

Preferably, the projection area of the adjacent hot melting modules on the heat conducting block is equal to the area of the heat conducting block.

The projection area of the adjacent heat fusion blocks on the heat conducting block is equal to the area of the heat conducting block, so that the area of the heat fusion block can be increased to the greatest extent, the heat transfer area of the heat fusion block is increased, and the hot press of the PCB is enabled to be more compact.

Preferably, adjacent heat-melting blocks extend inwards along the wide edges of the two sides of the heat-conducting block respectively.

The hot melt module extends inwards along the broadsides of the two sides of the heat conducting block, so that the area of the hot melt module is increased, the heat conducting efficiency is improved, the melting and solidification of the hot melt adhesive are accelerated, and finally the production efficiency of the PCB is improved.

Preferably, the thermal melting block occupies a half area of the heat conducting block.

The heat-transfer pattern block occupies a half area of the heat-transfer block, so that the heat transfer effect and the heat transfer speed between adjacent plates are more consistent, and the consistency of the hot pressing process is more effectively ensured.

Preferably, the heat conducting block is arranged near the corner of the PCB board, the width of the heat conducting block is 4 mm to 6 mm, the length of the heat conducting block is 22 mm to 26 mm, the width of the heat melting module is the same as the width of the heat conducting block, and the length of the heat melting module is equal to half of the length of the heat conducting block.

The width interval of 4 millimeters to 6 millimeters can compromise thermal conduction efficiency, glue film homogeneity, and 22 millimeters to 26 millimeters's length interval is when guaranteeing hot melt efficiency, reduces thermal stress concentration and warp as far as possible, and the heat conduction area is close to the corner setting of PCB board, can reduce the phenomenon that hot melt adhesive flows heat conduction area effectively to ensure that hot melt adhesive distributes evenly in the heat conduction area, improves the quality and the reliability of PCB board after the pressfitting.

Preferably, the thickness of the hot melting module is smaller than or equal to the thickness of the PCB substrate.

The thickness of the hot melting module is smaller than or equal to that of the PCB base material, so that the hot melting module can be effectively prevented from deforming in the pressing process, and the flatness and reliability of the pressed PCB are improved.

Preferably, the hot melting module is made of the same material as the PCB circuit.

The hot melting module and the PCB circuit are made of the same material, so that the production flow can be simplified, the hot melting module and the PCB circuit can be synchronously manufactured, and the production cost is reduced.

Preferably, the hot melting module is provided with a window.

The design of opening the window can facilitate the flow of the hot melt adhesive, improve the uniformity of the hot melt adhesive, reduce the phenomenon that the surface of the PCB is uneven after lamination, and improve the quality and reliability of the PCB.

Preferably, the windows are uniformly arranged in the hot melt mold blocks, and the windows are rectangular in shape.

The windows are uniformly arranged in the hot melt mold blocks and are designed into rectangular shapes, so that the flow direction of the hot melt adhesive can be effectively controlled, the hot melt adhesive is ensured to be uniformly distributed in the hot melt mold block areas, the phenomenon that the thickness of the PCB is uneven after lamination is reduced, and the quality of the PCB is improved.

The beneficial effects of the utility model are as follows:

The utility model provides a multilayer PCB board, which is characterized in that a heat conducting block is arranged on each layer, a hot melting module is arranged in the heat conducting block, projections of adjacent hot melting blocks on the heat conducting block are not overlapped, and heat can be effectively transferred to hot melting glue by arranging the heat conducting block and the hot melting block, so that the melting and solidifying processes of the hot melting glue are accelerated, and the production efficiency of the PCB board is improved. The design that the projections of adjacent heat fusion blocks are not overlapped can effectively reduce the total thickness of the heat fusion modules at the heat conducting blocks, thereby improving the problem of uneven plate thickness and improving the production quality of the PCB.

Drawings

Fig. 1 is a partial view of a multilayer PCB board provided in embodiment 1 of the present application;

Fig. 2 is a partial view of the multilayer PCB board provided in embodiment 2 of the present application;

fig. 3 is a partial view of the multilayer PCB board provided in embodiment 3 of the present application;

Fig. 4 is a partial view of the multilayer PCB board provided in embodiment 4 of the present application.

Reference numerals:

100. The heat conduction block, 200, the hot melting module, 210, windowing.

Detailed Description

Preferred embodiments of the present utility model will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present utility model are shown in the drawings, it should be understood that the present utility model may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the utility model to those skilled in the art.

Example 1

As shown in fig. 1, the present embodiment provides a multilayer PCB board, which includes:

Each layer of the PCB is provided with a heat conducting block 100 between the PCB boards, the heat conducting blocks 100 are internally provided with heat melting modules 200 for conducting heat, the heat melting modules 200 occupy partial areas of the heat conducting blocks 100, and projections of adjacent heat melting modules 200 on the heat conducting blocks 100 are not overlapped.

It should be noted that, the partial coverage refers to that the thermal melting module 200 occupies a partial area of the heat conducting block 100, rather than the complete coverage. The fact that the projections of the adjacent hot melting modules 200 on the heat conducting block 100 are not overlapped means that corresponding positions of the hot melting modules 200 on the two adjacent layers of PCB boards on the heat conducting block 100 are not overlapped, so that thickness superposition of the hot melting modules 200 is avoided.

Further, the width and length of the heat conducting block need to be comprehensively considered in combination with the specific design of the PCB and the requirements of the hot pressing process. If the width of the heat conducting area is too narrow, the area of the hot melting module is very small, the heat conducting efficiency is reduced, meanwhile, the space reserved for glue to flow is also small, the glue layer is not beneficial to being evenly distributed, and the phenomena of cavity or glue overflow are easy to occur. If the width of the heat conducting area is too wide, the diffusion range of the hot melt adhesive is too large, and the layout of other functional areas on the PCB is affected. If the length of the heat conducting area is too short, the heat transferred by the hot melting module is reduced, and the quick melting of the prepreg glue is not facilitated. If the length of the heat conduction block is too long, thermal stress concentration can be caused, and buckling deformation is more likely to occur.

Specifically, in this embodiment, the PCB board is provided with 30 layers, the width of the heat conducting block 100 is 5mm, the length is 24 mm, and the heat conducting block 100 is disposed at the corners of the PCB board.

More specifically, in this embodiment, the PCB board is a rectangular board, the heat conducting block 100 is disposed near four corners of the PCB board, and the circuit material of the PCB board is copper, and the material of the heat melting module 200 is also copper.

More specifically, the heat-fusible pattern block 200 may be made of a material having good heat conductivity, such as aluminum, ceramic, or the like, which is different from the PCB board. At this time, the heat-fusible pattern block 200 may be prefabricated and then attached to the PCB board by SMT or other means.

Further, the same processing technology is adopted for the hot melting module 200 and the circuit of the PCB, redundant copper is removed on the copper-clad plate through etching, and copper at the position of the hot melting module 200 is reserved.

More specifically, in the present embodiment, the width of the heat fusion block 200 is the same as that of the heat conduction block 100, and is also 5mm, and the length of the heat fusion block 200 is half of the length of the heat conduction block 100, and the length is 12 mm.

Still further, the heat-fusible pattern block 200 is further provided with a window 210, the window 210 is rectangular, more specifically, the window 210 is square with a side length of 1 mm, the windows 210 are uniformly arranged in the heat-fusible pattern block 200, the window 210 is provided with two rows, each row is provided with 5, the vertical and horizontal intervals between the windows 210 are 1 mm, the distance between the window 210 and the edge of the heat-fusible pattern block 200 is 1 mm, in other words, the heat-fusible pattern block 200 is a net structure formed by copper wires with a width of 1 mm, 3 copper wires are arranged in parallel in the length direction, the interval between the copper wires is 1 mm, 6 copper wires are arranged in parallel in the width direction, and the interval between the copper wires is 1 mm.

In the prior art, copper layers are covered in the whole heat conducting block 100 of each layer of PCB, and then copper layers with the thickness of 29 layers are added between 30 layers. While in this embodiment, only a thermal melting block 200 with 15 layers of superimposed thickness is added between 30 layers.

In particular, the window 210 may be circular, triangular, or other shape that facilitates glue flow. The size and arrangement of the windows 210 can also be adjusted according to actual requirements.

More specifically, in the present embodiment, the heat conducting block 100 is symmetrically divided into a first block and a second block along the short axis, and two heat-melting modules 200 of adjacent layers are respectively located in the first block and the second block, in other words, the heat-melting modules 200 are alternately arranged in the first block or the second block in the PCB board.

Further, the thickness of the hot melt module 200 is less than the thickness of the PCB substrate.

And when the PCB is hot-pressed, applying high temperature and high pressure to the PCB. At this time, the heat-fusible pattern block 200 can rapidly and uniformly transfer heat due to its copper structure, so that the prepreg glue below and around it is rapidly melted. The structure of the window 210 on the hot-melt module 200 is beneficial to the flow and filling of the melted glue, and further ensures the uniformity and firmness of the adhesion between the layers of the PCB.

The multilayer PCB board provided in this embodiment, through setting up heat conduction block 100 between every layer of PCB board to adopt the staggered arrangement, have the hot melt module 200 of windowing 210 structure, the copper structure of hot melt module 200 can be fast, evenly transfer heat, improves hot press efficiency. The window 210 on the hot melt module 200 facilitates the flow and filling of the molten glue, avoids glue layer build-up or shortfall, and improves the uniformity and reliability of adhesion. The heat-melting modules 200 are arranged in a staggered manner, do not cover the whole heat-conducting block 100, are favorable for uniform distribution of heat, and can also reduce the thickness of the whole heat-melting module 200 and prevent the PCB from being raised or deformed due to the too thick heat-melting module 200.

Example 2

As shown in fig. 2, the present embodiment provides a multilayer PCB board, which includes:

Specifically, in this embodiment, the multi-layer PCB board is provided with 20 layers in total, the circuit material of the PCB board is silver material, the heat conducting block 100 is disposed at the corners and the center of each side of the PCB board, and the heat conducting block 100 is a rectangular area with a width of 4 mm and a length of 26 mm.

Further, the heat-melting module 200 is disposed along the length direction of the heat-conducting block 100.

Specifically, the thermal melting module 200 is composed of silver wires with a width of 1mm, the silver wires are arranged in parallel along the length direction of the heat conducting block 100, the interval between the silver wires is 1mm, and the length is 26 mm.

To more clearly illustrate the arrangement of the thermal frits in this embodiment, the heat conducting block 100 is divided into 4 rows, each row has a length of 26 mm and a width of 1 mm, and the thermal melting modules 200 of adjacent layers are respectively located in the odd-numbered rows and the even-numbered rows of the heat conducting block 100, and in this embodiment, the thermal melting modules 200 of adjacent layers are respectively located in the 1 st row, the 3 rd row, the 2 nd row, and the 4 th row.

In the prior art, copper layers are covered in the whole heat conducting block 100 of each layer of PCB, and then copper layers with the thickness of 19 layers are added between 20 layers. While in this embodiment, only a hot-melt module 200 with a stacked thickness of 10 layers is added between 20 layers.

The multilayer PCB board that this embodiment provided through set up the heat conduction block 100 that has strip hot melt module 200 between every layer of PCB board to adopt the staggered arrangement's mode, the silver line structure of hot melt module 200 can be fast, evenly follow length direction transfer heat, improves hot pressing efficiency, is particularly useful for the great PCB board of length. The strip-shaped hot melting modules 200 and the staggered arrangement mode are beneficial to more uniform heat distribution, reduce the thermal stress concentration of the PCB in the length direction, effectively prevent the PCB from buckling deformation and improve the dimensional stability of the PCB.

Example 3

As shown in fig. 3, the present embodiment provides a multilayer PCB board, which includes:

Specifically, in this embodiment, the multi-layer PCB board is provided with 35 layers in total, the circuit material of the PCB board is copper material, the heat conduction block 100 is disposed at the corner of the PCB board, the heat conduction block 100 is a rectangular area with a width of 6 mm and a length of 22 mm, the heat conduction block 100 is divided into 6 rows, and the length of each row is 26 mm and the width is 1 mm.

Further, adjacent hot melt modules 200 extend inward along the length direction along both side wide edges of the heat conduction block 100.

Specifically, adjacent hot melt modules 200 are symmetrically arranged in a zipper shape.

More specifically, in the adjacent heat-fusible modules 200, one of the heat-fusible modules 200 extends inward by 6mm along one side broadside of the heat conduction block 100 and then continues to extend along the even row by 10 mm, and the other heat-fusible module 200 extends inward by 6mm along the other side broadside of the heat conduction block 100 and then continues to extend along the odd row by 10 mm.

Further, the heat-fusible pattern block 200 is further provided with a window 210, wherein the window 210 is a regular triangle with a side length of 1mm, and one side of the regular triangle is parallel to the wide side of the heat-conducting block 100.

In the prior art, copper layers are covered in the whole heat conducting block 100 of each layer of PCB, and then copper layers with the thickness of 34 layers are added between 35 layers of boards. While in this embodiment only a thermal melting block 200 with a superimposed thickness of 17 layers is added between 30 plies.

More specifically, the regular triangle window 210 is disposed within a range of 1006 mm from the heat conducting block 200, and for more clearly explaining the position of the window 210, the heat conducting block 200 is divided into 6 rows and 6 columns, each column and each row having a width of 1 mm, the window 210 is disposed within a range of 2-5 rows and 2-5 columns, wherein the regular triangle windows 210 in even columns are directed inward, the regular triangle windows 210 in even columns are directed outward, and the windows 210 in even columns and odd columns are staggered with each other.

And when the PCB multi-layer board is subjected to hot pressing, high temperature and high pressure are applied to the PCB board. The copper heat-fusible pattern block 200 can rapidly and uniformly transfer heat so that the prepreg glue around the block is rapidly melted, thereby firmly bonding the layers of the PCB boards together. At the same time, the "zipper-like" design and triangular fenestration 210 can direct the flow and distribution of glue, ensuring uniformity and reliability of adhesion.

Example 4

As shown in fig. 4, the present embodiment provides a multilayer PCB board, which includes:

Specifically, in this embodiment, the multi-layer PCB board is provided with 15 layers in total, the circuit material of the PCB board is copper material, the heat conduction block 100 is disposed at the corner of the PCB board, and the heat conduction block 100 is a rectangular area with a width of 6 mm and a length of 26 mm.

More specifically, adjacent hot melt modules 200 extend 10 mm inward along two 6mm wide sides of the heat conduction block 100, respectively. The projected area of two adjacent heat-melting modules 200 on the heat conducting block 100 is smaller than the area of the heat conducting block 100, specifically, in this embodiment, the area of the PCB board in the heat conducting block 100 is 156 square millimeters, and the projected area of two adjacent heat-melting modules 200 on the heat conducting block 100 is 120 square millimeters.

In the prior art, copper layers are covered in the whole heat conducting block 100 of each layer of PCB, and then copper layers with 14 layers of stacked thickness are added between 15 layers of boards. While in this embodiment only a thermal melting block 200 with a superimposed thickness of 7 layers is added between 15 layers.

In the multilayer PCB board in this embodiment, the area of the adjacent hot melting module 200 is smaller than the area of the PCB board in the heat conducting block 100, and the areas of the adjacent hot melting blocks in the heat conducting block 100 are not overlapped, so that the problem of the bulge of the PCB board caused by the thickness superposition of the hot melting module 200 can be effectively avoided, and meanwhile, the hot pressing efficiency and the pressing effect of the PCB board can be improved, and the quality of the pressing of the PCB board can be ensured.

The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless it is specifically stated otherwise. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that like reference numerals and letters refer to like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

It should be noted that the terms "first", "second", and the like are used for convenience of distinction, and the terms are not specifically defined unless otherwise stated, and thus should not be construed as limiting the scope of the present application.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims

1. A multi-layer PCB board, characterized by comprising:

Each layer of the PCB board is provided with a heat conduction block (100), and a hot melt module (200) for heat conduction is provided in the heat conduction block (100). The hot melt module (200) occupies a partial area of the heat conduction block (100), and the projections of adjacent hot melt modules (200) on the heat conduction block (100) do not overlap.

2. The multilayer PCB board according to claim 1 is characterized in that the heat conduction block (100) is rectangular, and the hot melt module (200) is distributed along the length direction or the width direction of the heat conduction block (100).

3. The multi-layer PCB board according to claim 1 is characterized in that the projection area of the adjacent hot melt modules (200) on the heat conduction block (100) is equal to the area of the heat conduction block (100).

4. The multilayer PCB board according to claim 2 is characterized in that adjacent hot melt modules (200) extend inward along the wide sides of both sides of the heat conduction block (100).

5. The multi-layer PCB board according to claim 2, characterized in that the hot melt module (200) occupies half of the area of the heat conduction block (100).

6. The multilayer PCB board according to claim 5 is characterized in that the heat conduction block (100) is arranged close to the corner of the PCB board, the width of the heat conduction block (100) is 4 mm to 6 mm, and the length is 22 mm to 26 mm, the width of the hot melt module (200) is the same as the width of the heat conduction block (100), and the length of the hot melt module (200) is equal to half the length of the heat conduction block (100).

7. The multilayer PCB board according to any one of claims 1 to 6, characterized in that the thickness of the hot melt module (200) is less than or equal to the thickness of the PCB board substrate.

8. The multi-layer PCB board according to any one of claims 1 to 6, characterized in that the hot melt module (200) is made of the same material as the PCB circuit material.

9. The multi-layer PCB board according to any one of claims 1 to 6, characterized in that a window (210) is provided on the hot melt module (200).

10. The multi-layer PCB board according to claim 9, characterized in that the windows (210) are evenly arranged in the hot melt module (200), and the shape of the windows (210) is rectangular.