Effects on etching rates of copper in ferric chloride solutions

Influences of several factors on etching rates of Cu in FeCl3 etchant are studied with a spray etching apparatus in this paper. The etching surfaces of Cu are analyzed by XRD and it proves that there is a CuCl passitivation film on the etching surface. A brief explanation is offered based on the relationship between etching rate and etching time. It indicates that cations influence the etching rate as the effects of different chlorides on etching rates have been studied. Additionally, the quantity of copper dissolved in FeCl3 etchant and regeneration of spent etchants are also investigated in this paper.