Patent ID: 7078351

Claim:
A method for patterning a semiconductor surface by applying etch processes, comprising: forming a layer on a substrate; forming a layer of BARC over the surface of said layer on the substrate; forming a first hardmask with a first thickness over said layer of BARC; forming a second hardmask with a second thickness on said first hard mask, the second thickness of the second hard mask being less than the first thickness of the first hard mask, the second hard mask comprising material different than material of the first hardmask, assuring an etch selectivity between the first and the second hard mask; forming a soft mask over said second hard mask; patterning and etching the soft mask, exposing the surface of the second hard mask; etching the exposed surface of the second hard mask, exposing the surface of the first hard mask; etching the exposed surface of the first hard mask, exposing the surface of the BARC; etching the exposed surface of the BARC, exposing the layer on the substrate; and etching the exposed surface of the layer on the substrate.