Patent ID: 6582856
Filing Date: 2003-06-24
Classification: G03F

Abstract:
A method of fabricating a phase shifting mask for use in the manufacture of an integrated circuit device comprising:providing a transparent substrate; depositing a contiguous, non-patterned opaque layer overlying said transparent substrate wherein said opaque layer consists of a multi-layer combination of silicon compounds alloyed with one of the group consisting of: chromium, chromium alloys, molybdenum, aluminum, tungsten, titanium, molybdenum silicide and carbon; thereafter depositing a resist layer overlying said opaque layer; thereafter patterning said resist layer; thereafter etching said opaque layer and said transparent substrate to thereby pattern said opaque layer and to form notches in said transparent layer wherein said resist layer masks said etching, wherein said opaque layer is etched through, wherein notches are etched into said transparent substrate only at each of the edges of said opaque layer, wherein said notches cause a phase shift in incident light relative to incident light passing through regions in said transparent substrate adjacent to said notches, and wherein an overetch is performed during said etching to remove any mask defects in said transparent substrate; and removing said resist layer to complete said phase shifting mask in the manufacture of said integrated circuit device.