Patent ID: 6399508
Filing Date: 2002-06-04
Classification: H01L

Abstract:
A method for etching a conductive layer on a semiconductor structure, wherein said semiconductor structure includes, from top to bottom, a patterned photoresist layer, an inorganic dielectric hard masking layer, at least one conductive layer, and a dielectric layer, all deposited on a surface of a semiconductor substrate, wherein said method comprises the steps of:a) pattern etching said dielectric hard masking layer through said patterned photoresist layer, using a plasma generated from a fluorocarbon-comprising gas, whereby an upper surface of said conductive layer is exposed through said patterned hard masking layer; followed by b) removing residual patterned photoresist material; followed by c) etching said semiconductor structure using a plasma generated from a source gas comprising chlorine and CHF3, whereby residues generated during pattern etching of said dielectric hard masking layer are removed; followed by d) etching said at least one conductive layer using a plasma generated from a source gas consisting essentially of nitrogen and a source for chlorine species.