Etching of copper with sulphuric acid/hydrogen peroxide solutions

Abstract

Removal of copper from copper clad laminate using sulphuric acid and hydrogen peroxide at the various stages of printed circuit manufacture is discussed and performances are compared with other processes available. The influence on performance resulting from additions of stabiliser for hydrogen peroxide, accelerators used to enhance the rate of attack of copper and inhibitors which prevent attack of metallic etch resists are examined. Techniques for recovery of copper are discussed together with details of equipment required for both small and large scale operation