Plasma etch method for forming patterned oxygen containing plasma etchable layer

Abstract

A method for forming a patterned oxygen containing plasma etchable layer. There is first provided a substrate. There is then formed upon the substrate a blanket oxygen containing plasma etchable layer. There is then formed upon the blanket oxygen containing plasma etchable layer a blanket hard mask layer. There is then formed upon the blanket hard mask layer a patterned photoresist layer. There is then etched while employing a first plasma etch method in conjunction with the patterned photoresist layer as a first etch mask layer the blanket hard mask layer to form a patterned hard mask layer. There is then etched while employing a second plasma etch method in conjunction with at least the patterned hard mask layer as a second etch mask layer the blanket oxygen containing plasma etchable layer to form a patterned oxygen containing plasma etchable layer. The second plasma etch method employs a second etchant gas composition comprising: (1) an oxygen containing etchant gas which upon plasma activation provides an active oxygen etching species; and (2) boron trichloride.

Dependencies are inferred from the claim text.