Patent ID: 8298954

Claim:
A method of patterning a structure comprising: forming a metal nitride layer on a substrate; forming a cap material layer having a different composition than said metal nitride layer directly on said metal nitride layer; forming a stack of an organic planarizing layer (OPL) and an antireflective coating (ARC) layer on said cap material layer; forming patterned line structures comprising a dielectric material on said ARC layer; simultaneously etching said cap material layer and at least one of said patterned line structures and said ARC layer, wherein a pattern present in said ARC layer is transferred through said OPL and said cap material layer, and a top surfaces of said metal nitride layer is exposed after said simultaneous etching; transferring said pattern from said OPL into said metal nitride layer; and transferring said pattern from said metal nitride layer into an upper portion of said substrate.