Etching a metal hard mask for an integrated circuit structure

摘要

The invention is a method of etching an integrated circuit (IC) structure that includes a metal hard mask layer. The etching of the metal hard mask layer is performed by first feeding a gas mixture comprising a fluorine containing gas and oxygen (O₂) gas to a reactor. The method then proceeds to generate a plasma that etches the metal hard mask layer. The method can be applied to either performing a via etch or a trench etch. Additionally, the invention teaches the removal of a photoresist layer without affecting the metal hard mask layer.