Etching method of PCB with two different copper thickness sides

Abstract

The invention relates to the circuit board making technology field and especially relates to the etching method of a PCB with two different copper thickness sides. In the invention, line graphs are made on the first surface and the second surface of a production board and pattern electroplating is performed, after a film is removed, the first surface is protected by a protective glue and etching processing is performed on the second surface, and then, the protective glue is used to protect the second surface and carry out etching processing on the first surface. The etching processing is performed on the two surfaces of the production board separately, and according to the copper layer thickness of each surface, an etching parameter is set so that a problem that over-etching occurs on thethinner side of a copper layer when the two sides are etched simultaneously can be avoided. The method of the invention can be used for etching the PCB whose the thickness difference of the two copperlayers reaches 2OZ.

Description

technical field [0001] The invention relates to the technical field of circuit board production, in particular to an etching method for PCBs with different copper thicknesses on both sides. Background technique [0002] In order to achieve different functional requirements, some PCBs need to have different copper thicknesses on both sides. For some special requirements, the difference between the copper thicknesses on both sides of the PCB is even required to be greater than 1.5OZ (1OZ=0.035mm). One of the technical difficulties in making PCBs with different copper thicknesses on both sides is line etching. The existing line etching method when making outer layer lines on PCBs with different copper thicknesses on both sides is: set the etching parameters based on the thicker copper side, Both sides are etched simultaneously. There are obvious defects and deficiencies in this line etching method. This etching method requires that the copper thickness difference between the t...

AI Technical Summary

Problems solved by technology

[0003] The present invention aims at the existing method of etching PCBs with different copper thicknesses on both sides, which requires that the copper thickness difference between the two sides should not be greater than 1OZ, and has strict requirements on the line distance, otherwise the problem of over-etching will occur on the side with thinner copper thickness, and provides a PCB with two sides. Etching method also applicable when the copper thickness difference is greater than 1OZ