CN-122002713-A - Manufacturing method of PCB (printed circuit board) press-connection hole and sub-board for PCB lamination press-connection

Abstract

The invention relates to the technical field of printed circuit board manufacturing, in particular to a manufacturing method of a PCB press-fit hole and a sub-board for PCB lamination press-fit, wherein the method comprises the steps of manufacturing the sub-board with the press-fit hole, filling the press-fit hole in the sub-board, keeping the shape of the used filling material stable at the lamination press-fit temperature of lamination press-fit and removing the filling material after the lamination press-fit is finished, grinding the sub-board to enable the exposed surface of the filling material to be flush with the surface of the sub-board, performing pattern manufacturing on the sub-board, laminating the sub-board with other board layers to obtain a mother board, performing through hole machining and outer layer pattern manufacturing on the mother board, performing depth control drilling on the press-fit hole to expose the filling material in the press-fit hole, removing the filling material in the press-fit hole, and performing effective protection on the press-fit hole in the lamination press-fit process and completely restoring the press-fit hole to be in a usable state after the lamination press-fit is finished.

Inventors

• JIAO QIZHENG
• WANG XIAOPING
• LIN YUCHAO
• ZUO CHENGWEI

Assignees

• 生益电子股份有限公司

Dates

Publication Date

20260508

Application Date

20260327

Claims (10)

1. 1. The manufacturing method of the PCB crimping hole is characterized by comprising the following steps: Manufacturing a daughter board with a crimping hole; filling holes in the crimping holes in the daughter board, wherein the filling material is stable in shape at the lamination temperature of lamination and can be removed after lamination is completed; grinding the daughter board so that the exposed surface of the filling material is flush with the surface of the daughter board; Carrying out graph manufacture on the daughter board; Laminating the daughter board and other board layers to obtain a mother board; processing a through hole and manufacturing an outer layer pattern on the mother board; drilling the crimping holes in a depth-controlled manner so as to expose the filling material in the crimping holes; And removing the filling material in the crimping holes.
2. 2. The method of manufacturing as set forth in claim 1, wherein before the filling the crimp holes in the daughter board, further comprising: and selectively carrying out surface treatment on the hole wall of the crimping hole to form a gold plating layer or a gold precipitation layer on the hole wall.
3. 3. A method according to claim 1 or 2, wherein the patterning is performed as a single sided patterning of only a surface of the sub-board facing away from the butt-joint surface of the laminate.
4. 4. The manufacturing method according to claim 1 or 2, wherein the filler material is a resin that is hydrolytically removable in an alkaline solution, and the removing of the filler material in the crimp hole specifically includes: the master is placed in the alkaline solution to hydrolytically remove the filler material.
5. 5. The method of claim 4, wherein the resin is a low-cure resin having active functional groups that are capable of undergoing hydrolysis in an alkaline solution in the polymer chains.
6. 6. The method of claim 4, wherein the alkaline solution is at least one of a sodium hydroxide solution, a potassium hydroxide solution, or a sodium carbonate solution.
7. 7. The method according to claim 4, wherein the mass fraction of the alkali in the alkaline solution is 3% -5%, and the temperature of the alkaline solution is 50 ℃ to 60 ℃.
8. 8. The method of manufacturing of claim 1 or 2, wherein the removing the filler material within the crimp hole further comprises: Simultaneously applying ultrasonic vibration to the motherboard, wherein the application time of the ultrasonic vibration is 3 minutes to 5 minutes.
9. 9. The manufacturing method according to claim 1 or2, wherein the difference between the diameter of the drill used for the depth-control drilling and the diameter of the crimping hole is 0.1mm-0.15mm on one side, and the depth of the depth-control drilling is identical to the depth of the crimping hole.
10. 10. The daughter board for lamination and lamination of the PCB is characterized in that a crimping hole is formed in the daughter board, a filling material is filled in the crimping hole, the filling material keeps stable in shape at the lamination temperature of lamination and can be removed after lamination and lamination is completed, and the exposed surface of the filling material is flush with the surface of the daughter board.

Description

Manufacturing method of PCB (printed circuit board) press-connection hole and sub-board for PCB lamination press-connection Technical Field The invention relates to the technical field of printed circuit board manufacturing, in particular to a manufacturing method of a PCB crimping hole and a sub-board for PCB lamination. Background In the fabrication of multi-layer PCBs, crimp holes are an important hole-type structure for inserting connector pins to achieve electrical interconnection between boards. The multi-layer PCB with the crimp holes generally adopts a manufacturing method of manufacturing a daughter board with the crimp holes and then laminating the daughter board with other board layers to form a motherboard. In the lamination pressing procedure, the prepreg in the lamination structure is in a molten flow state under the conditions of high temperature and high pressure, resin components in the prepreg are driven to flow to the holes under the pressure, so that the prepreg is very easy to infiltrate into the inner cavities of the press-fit holes, and after the pressing is completed, cooling and solidification, the infiltrated resin forms permanent filling in the holes, so that the size of the press-fit holes is reduced, even the press-fit holes are completely blocked, the smooth pressing of the pins of the subsequent connector is affected, and the PCB product is scrapped in severe cases. There are several related solutions in the prior art to address the resin filling problem of PCB holes. One proposal relates to the method that after the PCB is pressed and the back drilling is processed, resin is injected into the back drilling for permanent filling, and then the filling position of the resin is filled up through grinding plates and subsequent electroplating procedures, so as to solve the problem of permanent plugging of the back drilling. Another solution is to apply a combination of multi-stage copper layer plating and resin filling to the via, again targeting permanent resin hole filling, with the resin remaining in the hole after curing. The scheme adopts the permanent filling of the resin into the holes as the final purpose, the used resin is irreversibly solidified, and the resin cannot be removed from the holes after the lamination is completed. The scheme cannot solve the contradiction that in the lamination and pressing process of the multi-layer PCB, the pressing holes are required to be temporarily protected to prevent the prepreg resin from penetrating, and after the lamination and pressing process is finished, the pressing holes are required to be completely restored to be in a hollow state for pressing in the connector pins. The prior art has a functional deficiency in the application scenario. Therefore, there is a need for a method for fabricating a PCB crimp hole and a sub-board for lamination of a PCB laminate to overcome the above-mentioned drawbacks. Disclosure of Invention The invention aims to provide a manufacturing method of a PCB press-fit hole and a daughter board for PCB lamination press-fit, which can effectively protect the press-fit hole in a lamination press-fit procedure and completely restore the press-fit hole to a usable state after press-fit is completed. To achieve the purpose, the invention adopts the following technical scheme: in a first aspect, the present invention provides a method for manufacturing a PCB crimp hole, including the steps of: S1, manufacturing a daughter board with a crimping hole; S2, filling holes in the crimping holes in the daughter board, wherein the used filling material keeps stable shape at the lamination temperature of lamination and can be removed after lamination is completed; S3, grinding the daughter board so that the exposed surface of the filling material is flush with the surface of the daughter board; S4, carrying out graph manufacture on the daughter board; S5, laminating the daughter board and other board layers to obtain a mother board; S6, processing through holes and manufacturing outer layer patterns on the mother board; s7, drilling the pressure welding hole in a depth-controlled manner so as to expose the filling material in the pressure welding hole; s8, removing the filling material in the crimping hole. Preferably, before the step S2, the method further includes: and selectively carrying out surface treatment on the hole wall of the crimping hole to form a gold plating layer or a gold precipitation layer on the hole wall. In some preferred embodiments, the pattern is made as a single sided pattern made on only the side surface of the daughter board remote from the butt-joint face of the laminate press-fit. In some preferred embodiments, the filling material is a resin that is hydrolytically removable in an alkaline solution, and the step S8 specifically includes: the master is placed in the alkaline solution to hydrolytically remove the filler material. Specifically, the resin is a low-cure resin, and the polymer