MODELING OF INPLANE DISTORTIONS DUE TO VARIATIONS IN ABSORBER STRESS

The effort to achieve sub-0.25 mu m X-ray lithography depends, in part , on the ability to maintain strict fabrication control leading to low distortion X-ray masks. This paper presents finite element (FE) model s developed to identify sources of pattern in-plane distortions (IPD) during mask fabrication. In particular, mask fabrication processes ind ucing both uniform and non-uniform absorber stresses and the resulting distortions due pattern transferring through these stressed layers ha ve been investigated.