Mixed-pressing PCB degumming process

Abstract

The invention provides a mixed-pressing PCB degumming process which comprises the following steps: S1, performing mixed pressing on different types of materials to manufacture a PCB which comprises afirst material and a second material which are different in degumming difficulty, and the degumming difficulty of the second material is higher than that of the first material, S2, drilling a throughhole in the laminated PCB, respectively forming glue residues on the hole walls of the hole sections, corresponding to the first material and the second material, in the through holes; S3, after drilling, plugging the through hole with resin; S4, drilling the plug hole, machining a first drilled hole with the small diameter in the resin in the hole section corresponding to the first material, andmachining a second drilled hole with the large diameter in the resin in the hole section corresponding to the second material; and S5, selecting a glue removing mode, and removing glue residues and resin on the corresponding hole section of the first material and glue residues and resin on the corresponding hole section of the second material at the same time. According to the mixed-pressing PCB degumming process, degumming of the mixed-pressing PCB can be completed at the same time at a time.

Description

technical field [0001] The invention relates to the technical field of PCB production, in particular to a mixed pressure PCB glue removal process. Background technique [0002] With the rapid development of 5G communication technology, the demand for materials by end customers is increasing, and the functional requirements for materials are also becoming more and more abundant. At present, the mixed pressure of high-speed materials and FR4 materials, the mixed pressure of high-speed materials and high-frequency materials, and the mixed pressure of high-speed materials and functional materials are widely used in PCB manufacturing. Due to the significant difference in the ease of degumming of different types of materials, the control of the amount of degumming on the hole wall after drilling the PCB with mixed-pressure structure has always been a difficult point that technology research wants to break through. Specifically, when two materials with significantly different leve...

AI Technical Summary

Problems solved by technology

Specifically, when two materials with significantly different levels of glue removal are mixed and pressed into a PCB, glue slag is formed on the hole wall after drilling. Specifically, the PCB will generate instantaneous high temperature when drilling, and the substrate (commonly FR-4) or the resin material used to connect the copper layers is a poor conductor, and the heat will be highly accumulated during drilling, and the surface temperature of the hole wall will melt when the temperature of the hole wall exceeds the glass transition temperature of the resin. Flow, thus forming a thin layer of slag, the slag is not the burrs and burrs drilled by mechanical drilling, the slag is mainly hydrocarbons, if the slag is not removed, it will make the inside of the multi-layer board The layer signal line is not connected, or the connection is unreliable, so it is necessary to remove the glue. Generally, plasma and chemical glue removal are used. During the glue removal process, the glue removal parameters (the same glue remover, the same glue removal concentration, the glue removal time and other parameters ) often cannot match the desmearing effect of the two materials well at the same time

When the degumming parameters of easy-to-remove materials are selected, it is easy to cause incomplete degumming of the pore wall of difficult-to-remove materials. When the degumming parameters of difficult-to-remove materials are selected, it is easy to cause excessive degumming of easy-to-remove materials.

[0003] For the research on the removal of adhesive slag on PCB hole walls under mixed pressure, the industry mainly focuses on the optimization of adhesive removal parameters. However, due to the mixed pressure characteristics of materials, the selection range of adhesive removal parameters is often very small, or even non-existent.

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