Phase-shifting mask for equal line/space dense line patterns

Abstract

A phase-shifting mask suited for equal line/space, small pitched, dense line pattern is disclosed. The phase-shifting mask includes a transparent substrate, a partially shielded mesa line pattern of first phase formed on the substrate, and a 100% clear recessed line pattern of second phase etched into the substrate and is disposed right next to the partially shielded mesa line pattern. The partially shielded mesa line pattern has a plurality of alternating 45-degree, oblique areas and 100% transmittance clear regions of the first phase. The partially shielded mesa line pattern and the clear recessed line pattern have the same line width. The light that passes through the clear regions of the first phase and the light that passes through the clear recessed line pattern of second phase have a phase difference of 180 degree.

Dependencies are inferred from the claim text.