Copper etching with cupric chloride and regeneration of waste etchant

Abstract

Copper etching is considerably important process in electronics industry, particularly in the fabrication of printed circuit board. Various etchants can be used for this purpose, but nowadays cupric chloride is more accepted etchant, because of its high etch rate and easy regeneration properties. In the present study, copper etching process with cupric chloride etchant was investigated. In the etching of copper, the most important etching parameter is etch rate, therefore the investigation was based on the various effects on etch rate. The influence of etchant concentration, additives and etching temperature were examined. It is also important to regeneration/recycle of waste etchant from environmental point of view. Thus, various cupric chloride etchant regeneration processes were investigated.