Processing method of circuit board pattern transfer

Abstract

The invention provides a processing method of circuit board pattern transfer. The method comprises a step of carrying panel copper plating on the surface of a circuit board and an inner wall of a viahole, carrying out panel tin plating on the surface of the circuit board and the via hole, and generating a tin layer on a copper layer, a step of scanning and etching the tin layer on the circuit board by laser with laser imaging equipment, etching a tin layer of a non-conductor part to expose the copper layer, reserving a tin layer of a conductor part to be an erosion resistance layer of alkaline etching of the circuit board, a step of carrying out alkaline etching, using an alkaline etching solution to etch away the exposed copper layer on the circuit board, reserving a part of the copper layer covered by the tin layer, and a step of carrying out tin removal, using a tin removal solution to dissolve and remove a residual tin layer on the circuit board and obtaining a circuit pattern tocomplete the pattern transfer of the circuit board. According to the method, production processes are reduced, the production efficiency is improved, the environmental protection is improved, and theautomatic production is facilitated.

Description

technical field [0001] The invention belongs to the technical field of circuit processing, in particular to a processing method for pattern transfer of circuit boards. Background technique [0002] With the development of printed circuit board or IC carrier board technology, the circuit pattern is getting finer and finer, and thinner resist layer (dry film or wet film) is required to make precise circuit pattern. However, traditional dry film masking The process does not allow the dry film to be continuously thinned, otherwise the dry film used for hole masking is easy to break, causing the etching solution to enter the hole, there is no copper in the via hole, and the electrical connection fails; that is, the traditional dry film hole masking process, in order to ensure the hole masking effect, The dry film thickness should be greater than 30 microns. The thicker the dry film thickness, the lower the resolution and the worse the adhesion, and the spacing limit for making ci...

AI Technical Summary

Problems solved by technology

[0005] The traditional process of manufacturing line spacing less than 50 microns, especially printed circuit boards or IC substrates less than 30 microns, the pattern transfer process requires a 1000-class clean room, and the construction and maintenance of a 1000-class clean room is expensive and difficult to manage large and takes up a lot of space

[0006] The current transfer processing of circuit board graphics usually requires development and film removal operations, which not only has a long process and affects efficiency, but also produces a large amount of organic waste liquid and waste water during development and film removal. The waste liquid and waste water with high COD content is difficult and expensive to treat. High, not conducive to environmental protection, not conducive to cost reduction

At the same time, the development operation has adverse effects on the production of precision circuits, which is the main cause of open and short circuits

The traditional process is long, which is not conducive to the connection of the process, and is not conducive to automation or intelligent manufacturing

[0007] The traditional process usually includes: copper plating on the whole board - surface treatment - pressure sensitive dry film - exposure - development - acid etching - film removal, at least these seven processes, each process involves a lot of corresponding equipment, resulting in space The occupation is also more, requiring a larger production workshop

Images