Manufacturing method of copper block embedded PCB (Printed Circuit Board)

Abstract

The invention discloses a manufacturing method of a PCB embedded with a copper block, and the method comprises the following steps: manufacturing the copper block: manufacturing the copper block according to the size of a milling groove of the PCB, enabling the size of the copper block to be 3-4mil larger than that of the whole milling groove, and carrying out the chamfering and chamfering of the copper block; a milling groove is manufactured, a rough milling and finish milling combined groove milling mode is adopted, the cutter diameter of a rough milling cutter is phi 1.6 mm, the diameter of a finish milling cutter is phi 1.0 mm, the finish milling feeding speed is 0.5-0.6 m / min, and the lamination height is smaller than or equal to 3.0 mm; embedding a copper block, namely putting the copper block above the milling groove, calibrating the positions of the copper block and the milling groove by using infrared rays of a punching machine, cleaning a pressure head of the punching machine, and starting the punching machine to embed the copper block into the milling groove. According to the manufacturing method of the PCB embedded with the copper block, the combination degree of the copper block and the groove wall and the flatness of the embedded copper block can be improved, and therefore the quality of the PCB embedded with the copper block is improved.

Description

Technical Field

[0001] The invention relates to the technical field of printed circuit board manufacturing, and in particular to a manufacturing method of a PCB board embedded with copper blocks. Background Art

[0002] As electronic products become smaller and smaller, the size of PCB (printed circuit board) is also constantly shrinking, and the circuit design is becoming more and more intensive. As the power density of components increases, the heat dissipation of PCB is too large, which affects the service life, aging and even failure of components. Based on the development of new generation information technology, energy-saving and new energy vehicles, power equipment and other fields, the solution to the heat dissipation problem is imminent. At present, there are many ways to solve the heat dissipation problem of PCB. One of the effective ways is to directly embed a metal copper block with high thermal conductivity inside the printed board.

[0003] The copper block embedding process is to embed the copper block in the pre-milled straight through groove on the PCB, and then connect the copper block to the groove wall by mechanical force. In the existing process, the copper block embedding has the following problems: (1) The copper block shape design affects the copper block embedding effect, causing damage to the copper block and the groove wall, resulting in a high scrap rate; (2) There is a deviation between the size of the substrate milling groove and the size of the copper block: the copper block and the groove wall cannot be worn together, so that the embedded copper block and the substrate groove wall cannot be in close contact, the copper block will produce relatively serious wear, and the exposed copper block between the groove walls is easily corroded when exposed to the natural environment, which will shorten the service life of the finished product; (3) Since the copper block is embedded by mechanical force, the flatness of the copper block is difficult to meet the conventional requirements of the component surface and the welding surface, which will cause a large height difference and greatly reduce the heat dissipation effect of the electronic component and the copper block.

[0004] In view of this, it is necessary to provide a new copper block embedding process to solve the above technical problems. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for manufacturing a PCB board with embedded copper blocks, which can improve the bonding degree between the copper block and the slot wall and the flatness of the embedded copper block, thereby improving the quality of the PCB board with embedded copper blocks.

[0006] The technical solution of the present invention is as follows:

[0007] A method for manufacturing a PCB board with embedded copper blocks comprises the following steps:

[0008] Step S1, making a copper block, making the copper block according to the size of the PCB milling slot, making the copper block 3-4 mil larger than the overall milling slot, and performing chamfering and chamfering on the copper block;

[0009] When the PCB board is a double-layer board, the short side of the copper block is ≥5mm, the long side is ≤7mm, and the thickness is 0.90mm≤<1.2mm; when the PCB board is a multi-layer board, the short side of the copper block is ≥5mm, the long side is ≤40mm, and the thickness is ≥1.2mm;

[0010] Step S2, making a milling groove, using a milling groove method combining rough milling and fine milling, wherein the rough milling cutter diameter is φ1.6mm, the fine milling cutter diameter is φ1.0mm, the fine milling speed is 0.5-0.6m / min, and the stacking height is ≤3.0mm;

[0011] Step S3, embedding the copper block, placing the copper block above the milling groove, and using the infrared of the punching machine to calibrate the position of the copper block and the milling groove, and after cleaning the punch head of the punching machine, start the punching machine to embed the copper block into the milling groove;

[0012] When the PCB board is a double-layer board, the copper block is embedded in the surface ±3mil and protrudes from the surface ±4mil; when the PCB board is a multi-layer board, the copper block is embedded in the surface ±3mil and protrudes from the surface +4mil / -6mil.

[0013] Furthermore, in step S1, the copper block includes copper teeth, the protruding R angle of the copper teeth is 0.5 mm, the recessed R angle is 1.5 mm, and the height tolerance of the copper teeth is ±0.05 mm.

[0014] Furthermore, in step S1, the length / width tolerance of the copper block is ±0.05 mm, the thickness tolerance is ±0.03 mm, the chamfer R angle is 0.5 mm, and the chamfer angle is 60°.

[0015] Furthermore, after the copper block is embedded in the milling groove, the number of concave points on the surface of the copper block is ≤3.

[0016] Compared with the prior art, the method for manufacturing a PCB board with embedded copper blocks provided by the present invention has the following beneficial effects:

[0017] The manufacturing method of the copper block embedded PCB board provided by the present invention, when manufacturing the copper block, the size of the copper block is larger than the whole milling groove, so that the copper block and the milling groove are closely combined, and the groove wall damage is avoided by the chamfering and chamfering process, so as to improve the adaptability of the copper block and the milling groove; when milling the groove, the combination of rough milling and fine milling is adopted to improve the accuracy of the milling groove processing, and ensure that the copper block and the milling groove are compatible in shape and size; when embedding the copper block, the two are accurately positioned by infrared rays to improve the fit between the copper block and the milling groove, and the punch head is cleaned to prevent dents from appearing on the surface of the copper block. After the copper block is embedded in the milling groove, the copper block and the groove wall can be closely combined, so as to avoid the copper block being exposed to the natural environment and being corroded, and increase the service life of the finished product; at the same time, the surface of the copper block is flat, which can meet the requirements of the component surface and the welding surface, and ensure the heat dissipation effect of the product. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention and to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the specific implementation modes of the present invention are further described below.

[0019] It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as there is no conflict between them.

[0020] A method for manufacturing a PCB board with embedded copper blocks comprises the following steps:

[0021] Step S1, making a copper block, making the copper block according to the size of the PCB milling slot, making the copper block 4 mil larger than the overall milling slot, and chamfering the copper block, wherein the chamfer R angle is 0.5 mm and the chamfer angle is 60°;

[0022] When the PCB board is a double-layer board, the short side of the copper block is ≥5mm, the long side is ≤7mm, and the thickness is 0.90mm≤<1.2mm; when the PCB board is a multi-layer board, the short side of the copper block is ≥5mm, the long side is ≤40mm, and the thickness is ≥1.2mm; preferably, the length / width tolerance of the copper block is ±0.05mm, and the thickness tolerance is ±0.03mm;

[0023] When the copper block includes copper teeth, the protruding R angle of the copper teeth is 0.5mm, the recessed R angle is 1.5mm, and the height tolerance of the copper teeth is ±0.05mm;

[0024] Step S2, making a milling groove, using a milling groove method combining rough milling and fine milling, wherein the rough milling cutter diameter is φ1.6mm, the fine milling cutter diameter is φ1.0mm, the fine milling speed is 0.6m / min, the stacking height is ≤3.0mm, and the milling groove size accuracy is controlled to ±4mil;

[0025] Step S3, embedding the copper block, placing the copper block above the milling groove, and using the infrared of the punching machine to calibrate the position of the copper block and the milling groove, cleaning the punch head of the punching machine and then starting the punching machine to embed the copper block into the milling groove; cleaning the punch head of the punching machine can prevent dents from forming on the surface of the copper block;

[0026] When the PCB board is a double-layer board, the copper block is embedded in the surface ±3mil and embedded in the surface ±4mil; when the PCB board is a multi-layer board, the copper block is embedded in the surface ±3mil and embedded in the surface +4mil / -6mil. The copper block embedded in the milling groove must meet the requirement of ≤3 surface concave points, no solder mask and foreign matter residue.

[0027] In the copper embedding process, the embedding surface refers to the position where the copper block is embedded inside the PCB. The copper block embedding design can increase the cross-sectional area of ​​the wire, reduce resistance, improve current conduction capability, and absorb and disperse the heat generated by electronic components to improve heat dissipation performance. The protruding surface refers to the part of the PCB surface exposed after the copper block is embedded. The copper block protruding design makes part of the copper block visible on the PCB surface, which is usually used in key areas where heat dissipation or current conduction is required.

[0028] The manufacturing method of the copper block embedded PCB board provided by the present invention, when manufacturing the copper block, the size of the copper block is larger than the whole milling groove, so that the copper block and the milling groove are closely combined, and the groove wall damage is avoided by the chamfering and chamfering process, so as to improve the adaptability of the copper block and the milling groove; when milling the groove, the combination of rough milling and fine milling is adopted to improve the accuracy of the milling groove processing, and ensure that the copper block and the milling groove are compatible in shape and size; when embedding the copper block, the two are accurately positioned by infrared rays to improve the fit between the copper block and the milling groove, and the punch head is cleaned to prevent dents from appearing on the surface of the copper block. After the copper block is embedded in the milling groove, the copper block and the groove wall can be closely combined, so as to avoid the copper block being exposed to the natural environment and being corroded, and increase the service life of the finished product; at the same time, the surface of the copper block is flat, which can meet the requirements of the component surface and the welding surface, and ensure the heat dissipation effect of the product.

[0029] The embodiments of the present invention are described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations made to these embodiments without departing from the principles and spirit of the present invention are still within the protection scope of the present invention.

Claims

1. A method for manufacturing a copper-embedded PCB board, characterized in that: The steps include: Step S1, making a copper block, making the copper block according to the size of the PCB milling slot, making the copper block 3-4 mil larger than the overall milling slot, and performing chamfering and chamfering on the copper block; When the PCB board is a double-layer board, the short side of the copper block is ≥5mm, the long side is ≤7mm, and the thickness is 0.90mm≤<1.2mm; when the PCB board is a multi-layer board, the short side of the copper block is ≥5mm, the long side is ≤40mm, and the thickness is ≥1.2mm; Step S2, making a milling groove, using a milling groove method combining rough milling and fine milling, wherein the rough milling cutter diameter is φ1.6mm, the fine milling cutter diameter is φ1.0mm, the fine milling speed is 0.5-0.6m / min, and the stacking height is ≤3.0mm; Step S3, embedding the copper block, placing the copper block above the milling groove, and using the infrared of the punching machine to calibrate the position of the copper block and the milling groove, and after cleaning the punch head of the punching machine, start the punching machine to embed the copper block into the milling groove; When the PCB board is a double-layer board, the copper block is embedded in the surface ±3mil and protrudes from the surface ±4mil; when the PCB board is a multi-layer board, the copper block is embedded in the surface ±3mil and protrudes from the surface +4mil / -6mil.

2. The method for manufacturing a copper-embedded PCB board according to claim 1, characterized in that: In step S1, the copper block includes copper teeth, the protruding R angle of the copper teeth is 0.5 mm, the recessed R angle is 1.5 mm, and the height tolerance of the copper teeth is ±0.05 mm.

3. The method for manufacturing a copper-embedded PCB board according to claim 2, characterized in that: In step S1, the length / width tolerance of the copper block is ±0.05 mm, the thickness tolerance is ±0.03 mm, the chamfer R angle is 0.5 mm, and the chamfer angle is 60°.

4. The method for manufacturing a copper-embedded PCB board according to claim 1, characterized in that: After the copper block is embedded in the milling groove, the number of concave points on the surface of the copper block is ≤3.