A new, simple approach is given for the design of phase shifting masks using self-aligned rim shifters. First, a series of design curves are generated, which show all the combinations of rim width and chrome width which print a certain feature for a given process. Second, based on performance criteria for the critical feature(s) on the mask, a rim width is chosen. Finally, the design curves are used with the desired rim width to generate a bias rule which determines the needed chrome mask bias as a function of feature size and type. The result is an easy-to- fabricate self-aligned rim shifter mask with nearly the same performance benefits of a complicated two-level sized rim shifter mask. This technique is called the Biased Self-Aligned Rim Shifter.

Date Published: 26 March 1993
PDF: 8 pages
Proc. SPIE 1809, 12th Annual BACUS Symposium on Photomask Technology and Management, (26 March 1993); doi: 10.1117/12.142144

Published in SPIE Proceedings Vol. 1809:
12th Annual BACUS Symposium on Photomask Technology and Management
Scott Landstrom; Richard LaFrance, Editor(s)