A method and apparatus for etching a gold metal layer using titanium hardmask

摘要

Disclosed is an inventive method for etching a gold metallization in a plasma processing chamber. The method includes introducing a substrate having a gold layer and an overlying titanium hardmask layer into the plasma processing chamber. The hardmask is first etched using conventional etching techniques. Then a plasma is formed in the chamber from an oxidizing gas and an etching gas. The etching gas is preferably a hydrochloric acid containing gas which may contain a chlorine containing gas. In addition, N2 may be provided. The plasma is then used to etch the gold layer through the TiN or TiW hardmask.