METHOD TO PRODUCE HIGH DENSITY MEMORY CELLS AND SMALL SPACES BY USING NITRIDE SPACER

摘要

The present invention relates to a method for forming an etch mask. A photoresist layer is patterned, wherein d1 is a smallest space dimension of an exposed area of a layer underlying the photoresist layer. An ARC layer under the photoresist layer is etched. A nitride layer is formed to be conformal to the patterned ARC layer and exposed portions of an underlayer underlying the patterned ARC layer. The nitride layer is etched to form nitride sidewalls, the nitride sidewalls reducing the smallest space dimension of the exposed underlayer area to d2, wherein d2 < d1.