Patent ID: 6110837
Filing Date: 2000-08-29
Classification: H01L

Abstract:
A method for forming an oxide hard mask of half critical dimension on a semiconductor substrate, comprising:forming a silicon oxide layer on said semiconductor substrate;defining a photoresist pattern of a critical dimension on said silicon oxide layer;forming a first polymer layer on said photoresist pattern and on said silicon oxide layer, wherein said first polymer layer has a thickness of half critical dimension;removing said first polymer layer on a top surface of said photoresist layer and said silicon oxide layer;etching said silicon oxide layer using said first polymer layer and said photoresist layer as an etching mask;removing said photoresist pattern;forming a second polymer layer on said first polymer layer, on said silicon oxide layer and on said semiconductor substrate, wherein said second polymer layer has a thickness of quarter critical dimension;removing said second polymer layer on a top surface of said silicon oxide layer; andetching said silicon oxide layer using said first polymer layer and said second polymer layer as an etching mask to form an oxide hard mask of half critical dimension on said substrate.