REVISITING PHASE-SHIFTING MASKS IN X-RAY-LITHOGRAPHY

Citation
M. Khan et al., REVISITING PHASE-SHIFTING MASKS IN X-RAY-LITHOGRAPHY, Journal of vacuum science & technology. B, Microelectronics and nanometer structures processing, measurement and phenomena, 15(6), 1997, pp. 2255-2258
Citations number
9
ISSN journal
10711023
Volume
15
Issue
6
Year of publication
1997
Pages
2255 - 2258
Database
ISI
SICI code
1071-1023(1997)15:6<2255:RPMIX>2.0.ZU;2-L
Abstract
In this article, we describe a framework for selecting the materials f or phase shift masks (PSMs) in x-ray lithography to yield the optimal exposure latitude. Traditional design of PSMs involves choosing the th ickness of the material to produce a pi phase shift, as in the case of clear phase shifting masks, or to produce the sufficient contrast nee ded for imaging with a requisite phase shift to improve linewidth cont rol, as in the cases of attenuated phase shifting masks and half-tone phase shifting masks. We instead find the optical constants of a theor etical material that yield optimal exposure latitude, and try to find combinations or alloys of various materials that have the requisite op tical constants. (C) 1997 American Vacuum Society.