Plasma etching process for metals and metal oxides, including metals and metal oxides inert to oxidation

摘要

A method of etching a metal or metal oxide, including a platinum family metal or a platinum family metal oxide. A wafer is first provided which comprises: (a) a semiconductor substrate, (b) a metal or metal oxide layer over the semiconductor substrate, and (c) a titanium containing patterned mask layer having one or more apertures formed therein positioned over the metal or metal oxide layer. The metal or metal oxide is then etched through the apertures in the mask layer by a plasma etching step that uses plasma source gases comprising the following: (a) a gas that comprises one or more carbon-oxygen bonds (for example, CO gas or CO₂ gas) and (b) a gas that comprises one or more chlorine atoms (for example, Cl₂ gas, carbon tetrachloride gas, silicon tetrachloride gas or boron trichloride gas).