MEMC Etch—A Chromium Trioxide‐Free Etchant for Delineating Dislocations and Slip in Silicon

Abstract

This paper describes a new etching formula (MEMC etch) which does not employ chromium trioxide and generates no hazardous waste. MEMC etch is a copper nitrate‐based etchant that has proven useful for essentially all p and n‐type silicon production. The etchant displays a long lifetime without excessive solution heating, easily interpreted pits on (111), (100), and (511) surfaces, and the formula yields a planar etch rate similar to Sirtl etch. The MEMC formula can be used as a substitute for Sirtl or Wright etch in most applications which require screening material for dislocations and slip.