CN110636690B

CN110636690B - Heat dissipation substrate structure and manufacturing method thereof

Info

Publication number: CN110636690B
Application number: CN201911012051.5A
Authority: CN
Inventors: 余丞博; 王永海
Original assignee: KUNSHAN HULI MICROELECTRONICS CO Ltd
Current assignee: KUNSHAN HULI MICROELECTRONICS CO Ltd
Priority date: 2019-10-23
Filing date: 2019-10-23
Publication date: 2020-12-11
Anticipated expiration: 2039-10-23
Also published as: CN110636690A

Abstract

The invention discloses a heat dissipation substrate structure and a manufacturing method thereof, wherein the heat dissipation substrate structure comprises a heat dissipation block and two multi-layer plate assemblies which are respectively and fixedly connected with two side parts of the heat dissipation block; the multi-layer board assembly comprises a PP layer and at least two core layers; at least two core layers are laminated and insulated through PP layers, and one surface of each core layer, which is far away from the PP layer, is plated with a copper layer; in each multi-layer plate assembly, at least one core layer is arranged, and an HDI line added layer is arranged on one surface of the core layer, which is far away from the PP layer, so that a groove-shaped cavity region with the upper end surface or the lower end surface of the heat dissipation block as a bottom wall is formed between the HDI line added layers on the two multi-layer plate assemblies; and a copper layer is plated on one surface of the HDI line build-up layer, which is far away from the core layer. The invention can be suitable for a circuit board with high-density design, has excellent heat dissipation performance, and can reduce the thickness of the assembled circuit board.

Description

Heat dissipation substrate structure and manufacturing method thereof

Technical Field

The invention relates to the technical field of design of a heat dissipation assembly of a circuit board, in particular to a heat dissipation substrate structure of the circuit board suitable for high-density circuit design and a manufacturing method thereof.

Background

The development of consumer electronic products on the market tends to be smaller and thinner, but the functions are richer and the performance is more and more stable, which poses a high-density challenge to the circuit and packaging of the products.

The traditional technology adopts a mode of increasing a plurality of wiring layers in a PCB to realize high-density design of circuits, but the high-density circuit board also faces higher heat productivity, and if the heat dissipation problem cannot be solved properly, the performance of the product is greatly influenced.

Disclosure of Invention

The invention aims to provide a heat dissipation substrate structure and a manufacturing method thereof, which can be suitable for a high-density designed circuit board, have excellent heat dissipation performance and can reduce the thickness of the circuit board after integral assembly.

The technical scheme adopted by the invention is as follows:

on one hand, the invention provides a heat dissipation substrate structure, which comprises a heat dissipation block and two multi-layer plate assemblies respectively fixedly connected with two side parts of the heat dissipation block;

the multi-layer board assembly comprises a PP layer and at least two core layers;

the at least two core layers are laminated and insulated through PP layers, and one surface of each core layer, which is far away from the PP layer, is plated with a copper layer;

in each multi-layer plate assembly, at least one core layer is arranged, and an HDI line added layer is arranged on one surface of the core layer, which is far away from the PP layer, so that a groove-shaped cavity region with the upper end surface or the lower end surface of the heat dissipation block as a bottom wall is formed between the HDI line added layers on the two multi-layer plate assemblies; and a copper layer is plated on one surface of the HDI line build-up layer, which is far away from the core layer.

Optionally, the heat dissipation substrate structure further includes a heat dissipation substrate, one end of the heat dissipation substrate is connected to the heat dissipation block in the cavity region, and the other end of the heat dissipation substrate is provided with a plurality of heat dissipation teeth side by side. The arrangement of the heat dissipation substrate can further improve the heat dissipation capability of the substrate.

Optionally, in each multi-layer board assembly, a core layer is respectively pressed on the upper and lower PP layers in each multi-layer board assembly, and an HDI line build-up layer is respectively arranged on one surface of each core layer departing from the PP layer; a cavity region is formed between the two HDI line added layers positioned at the upper part/the lower part and between the upper end face/the lower end face of the radiating block.

Optionally, a solder mask layer is further arranged on one surface of the HDI line build-up layer, which is far away from the core layer; the upper surface and/or the lower surface of the heat dissipation block is/are provided with a copper layer; and the copper layers on the upper surface and/or the lower surface of the heat dissipation block are respectively provided with a solder mask layer.

Optionally, the heat dissipation block is a ceramic heat dissipation block.

In another aspect, the present invention further provides a method for manufacturing a heat dissipation substrate, including:

1) placing the heat dissipation block between the two groups of multi-layer plate assemblies; each multi-layer board assembly comprises a PP layer and at least 2 core layers which are respectively positioned above and below the PP layer, and one surface of each core layer, which is far away from the PP layer, is provided with a copper layer;

2) performing a pressing operation to enable at least 2 core layers in the multi-layer plate assembly to be pressed with the PP layer, and simultaneously pressing two end parts of the heat dissipation block with the side part of one multi-layer plate assembly respectively;

3) manufacturing a circuit layer on the copper layer of the core layer;

4) manufacturing a copper barrier layer 8 on the bottom edge of a pre-designed cavity region; the cavity area at least covers the upper end surface or the lower end surface of the radiating block;

5) integrally covering a release material on the bottom wall of the cavity region surrounded by the copper barrier layer 8;

6) manufacturing an HDI line added layer covering the release material on the core layer and the heat dissipation block;

7) taking out the HDI circuit added layer above the separated material by laser blind taking;

8) and removing the release material, and forming a groove-shaped cavity region between the upper end surface of the heat dissipation block and the HDI line added layers on the two sides.

Optionally, the thickness of the heat dissipation block is equal to the thickness of the multi-layer board assembly after being pressed.

Optionally, a copper layer is arranged on the upper end face and/or the lower end face of the heat dissipation block;

the method further comprises the following steps: step 2), grinding and removing PP layer insulating media at the joint of the heat dissipation block and the multi-layer board assembly after the pressing operation;

step 3) manufacturing a circuit layer on the copper layer of the heat dissipation block;

in the step 4), the cavity area extends from the upper end surface or the lower end surface of the radiating block to two sides and covers the end surface of the adjacent core layer;

and 6) after the HDI circuit added layer is manufactured, manufacturing solder masks on the upper surface and the lower surface of the substrate, and then performing the step 7).

Advantageous effects

The heat dissipation substrate structure of the invention enables the substrate to be suitable for the design of the HDI high-density circuit board by designing the cavity region and the HDI line added layer, and simultaneously utilizes the characteristic of high heat conduction and high insulation of the ceramic heat dissipation block, the heating assembly is assembled in the cavity region, the heat conduction path can be shortened, the heat conduction capability can be improved, and the overall thickness after the assembly can be reduced after the heating assembly is assembled with the substrate.

Drawings

Fig. 1 is a schematic cross-sectional view illustrating a heat dissipation substrate according to an embodiment of the invention;

FIG. 2 is a schematic view of an exemplary heat-dissipating substrate according to the present invention;

FIG. 3 is a schematic process flow diagram of a method for manufacturing a heat-dissipating substrate according to the present invention;

in FIGS. 1 to 3, 1-heat sink (ceramic), 11-heat sink surface copper layer, 2-multi-layer board assembly, 21-PP layer (Prepreg insulating layer), 22-core layer (core board), 23-core layer surface copper layer, 3-HDI wiring build-up, 31-HDI wiring build-up, 4-solder mask, 5-edge copper layer, 6-heat sink substrate, 61-heat sink teeth, 7-heat generating element, 8-release material.

Detailed Description

The following further description is made in conjunction with the accompanying drawings and the specific embodiments.

Example 1

Referring to fig. 1, the present embodiment is a heat dissipation substrate structure, which includes a heat dissipation block 1 and two multi-layer board assemblies 2 fixedly connected to two sides of the heat dissipation block respectively;

the multi-layer board assembly 2 comprises a PP layer 21 and at least two core layers 22;

at least two core layers 22 are pressed and insulated through the PP layer 21, and one surface of each core layer 22, which is far away from the PP layer 21, is plated with a copper layer 23;

in each multilayer board assembly, at least one core layer 22 is arranged, one surface of the core layer 22, which is far away from the PP layer 21, is also provided with an HDI line added layer 3, and one surface of the HDI line added layer 3, which is far away from the core layer 22, is plated with a 31 copper layer; the copper layer 23 and the copper layer 31 can be communicated through a blind hole according to the HDI circuit design;

a groove-shaped cavity region with the upper end face or the lower end face of the heat dissipation block as a bottom wall is formed between the HDI line added layers on the two multilayer plate assemblies.

Examples 1 to 1

With embodiment 1 as a basic structure, as shown in fig. 1 and fig. 2, in this embodiment:

the heat dissipation block is made of ceramic and has the characteristics of high heat conduction and high insulation.

In each multi-layer plate assembly, a core layer is respectively pressed on the upper part and the lower part of the PP layer, and an HDI line added layer is respectively pressed on one surface of the two core layers, which is far away from the PP layer; a cavity region is formed between the two HDI line added layers positioned at the upper part/the lower part and between the upper end face/the lower end face of the radiating block. That is, the heat dissipation substrate structure of the present embodiment forms two cavity regions.

And a welding-proof layer is also arranged on one surface of the HDI line build-up layer departing from the core layer. The protective coating can be used for protecting a copper layer on an HDI line build-up layer and preventing oxidation.

The upper surface and/or the lower surface of the heat dissipation block is/are provided with a copper layer. That is, the circuit layer can also be designed on the heat dissipation block. And the wiring layers on the upper surface and/or the lower surface of the heat dissipation block are respectively provided with a solder mask layer.

The heat dissipation substrate structure further comprises a heat dissipation substrate 6, one end of the heat dissipation substrate 6 is connected with the heat dissipation block 1 in the cavity area, and the other end of the heat dissipation substrate 6 is provided with a plurality of heat dissipation teeth 61 in parallel. The arrangement of the heat dissipation substrate can further improve the heat dissipation capability of the substrate.

The upper end and the lower end of the radiating block are respectively flush with the upper end and the lower end of the multilayer plate assembly; the bottom wall of the cavity area extends from the upper end of the heat sink block to both sides over the core layer at the end of the multi-layer plate assembly. The arrangement and connection of the larger heating elements 7 in the cavity region can be facilitated, and part of the process flow can be simplified.

By utilizing the heat dissipation substrate structure, the ceramic heat dissipation block has the characteristics of high heat conduction and high insulation, so that a circuit layer can be designed at the cavity to be communicated with other regions, the heating assembly can be assembled at the cavity region, the heat conduction path of the heating assembly can be shortened, a circuit for manufacturing a high-density HDI (high density interconnect) design is supported, and the design of a circuit board with more functions can be met; in addition, the groove design of the cavity area can reduce the thickness of the whole assembly, thereby achieving the structural design of the thin circuit board with high heat dissipation and high density.

Example 2

This embodiment provides a method for manufacturing a heat dissipation substrate, which may be the heat dissipation substrate in

embodiments

1 and 2.

Referring to fig. 3, the method for manufacturing the heat dissipation substrate includes the steps of:

3) manufacturing a circuit layer on the copper layer of the core layer;

A copper layer is arranged on the upper end face and/or the lower end face of the heat dissipation block; the thickness of the heat dissipation block manufactured by the method of the embodiment can be equal to that of the multi-layer board assembly after pressing, and the integrated copper laying and corresponding circuit design in the step 3 are facilitated.

The method comprises the following steps: step 2), after the pressing operation, grinding and removing redundant PP layer insulating media at the joint of the heat dissipation block and the multi-layer board assembly;

Example 2-1

Based on embodiment 2, the method of this embodiment may specifically include the following steps:

taking a substrate assembly at least provided with a PP layer and an upper core layer and a lower core layer, and taking out the middle part of the substrate assembly for placing a ceramic radiating block;

carrying out pressing operation on the PP layer, the core layer and the ceramic piece, and removing the residual PP medium at the joint through grinding;

laying copper on the surface of the core layer and the surface of the ceramic heat dissipation part to enable the circuit layer of the ceramic heat dissipation block to be communicated with other areas, subsequently manufacturing mechanical drilling, electroplating, circuit manufacturing processes and the like to form a circuit board with at least two layers of boards, and forming a subsequent laser fishing type copper barrier layer at an outer frame of a cavity area to be formed subsequently;

covering a cavity region on the ceramic heat sink block, and making a release material, wherein the release material can be made by printing, exposure and development, or pre-bonding, and then performing pressing and HDI (laser/mechanical drilling/electroplating/circuit/solder mask);

and after the anti-welding process, performing laser blind fishing operation, wherein the profile of the blind fishing operation is the formed copper barrier layer. If the demand of an outward communication line is met, the barrier layer can be designed to be opened, and the subsequent removal of materials on the cavity area is not influenced; then, the material and the release material on the cavity region are removed to form a cavity structure, and the conventional circuit board processes such as metal surface treatment are performed subsequently.

If a solder mask layer is required to be designed on the circuit layer at the cavity, a regional solder mask flow can be performed in the cavity circuit region after the circuit layer is formed and before the HDI circuit added layer is manufactured.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. A heat dissipation substrate structure is characterized by comprising a heat dissipation block and two multi-layer plate assemblies which are respectively and fixedly connected with two side parts of the heat dissipation block;

in each multi-layer plate assembly, at least one core layer is arranged, and an HDI line added layer is arranged on one surface of the core layer, which is far away from the PP layer, so that a groove-shaped cavity region with the upper end surface or the lower end surface of the heat dissipation block as a bottom wall is formed between the HDI line added layers on the two multi-layer plate assemblies; one surface of the HDI line added layer, which is far away from the core layer, is plated with a copper layer;

the LED lamp also comprises a heat dissipation substrate, wherein one end of the heat dissipation substrate is connected with a heat dissipation block in the cavity area, and the other end of the heat dissipation substrate is provided with a plurality of heat dissipation teeth side by side.

2. The heat dissipating substrate structure of claim 1, wherein in each multi-layer board assembly, a core layer is laminated on the upper and lower sides of the PP layer, and an HDI line build-up layer is disposed on a side of each core layer away from the PP layer; a cavity region is formed between the two HDI line added layers positioned at the upper part/the lower part and between the upper end face/the lower end face of the radiating block.

3. The heat dissipation substrate structure of claim 1 or 2, wherein a solder mask layer is further disposed on a side of the HDI line build-up layer away from the core layer.

4. The heat dissipating substrate structure according to claim 1 or 2, wherein the upper surface and/or the lower surface of the heat dissipating block is provided with a copper layer; and the copper layers on the upper surface and/or the lower surface of the heat dissipation block are respectively provided with a solder mask layer.

5. The heat dissipating substrate structure of claim 1, wherein the upper and lower ends of the heat slug are flush with the upper and lower ends of the multi-layer board assembly, respectively; the bottom wall of the cavity region extends from the upper or lower end of the heat sink block to both sides over the core layer at the end of the multi-layer board assembly.

6. The heat dissipating substrate structure of claim 1, wherein the heat slug is a ceramic heat slug.

7. A manufacturing method of a heat dissipation substrate is characterized by comprising the following steps:

3) manufacturing a circuit layer on the copper layer of the core layer;

4) manufacturing a copper layer for blocking laser blind fishing on the bottom edge of a pre-designed cavity area to serve as a copper blocking layer; the cavity area at least covers the upper end surface or the lower end surface of the radiating block;

5) integrally covering a release material on the bottom wall of the cavity region surrounded by the copper barrier layer;

8. The method of claim 7 wherein the heat slug has a thickness equal to the thickness of the multi-layer board assembly after lamination.

9. The method of claim 7, wherein the upper and/or lower end surfaces of the heat slug are provided with a copper layer;