Blurring effect analysis of an x-ray mask for synchrotron radiation lithography

During the process of synchrotron radiation lithography, blurring occurs largely because the mask and patterns are distorted under transient thermal loads. An analysis model of blurring has been proposed in this article. Irradiated energy is calculated by summing the moving x-ray power incident to a wafer. The blur is caused mainly by two sources: displacement of the pattern and pattern width change. A transient analysis has been made. In a sample calculation, the distortion of a printed pattern after the process was 1.2 nm while the maximum in-plane distortion during the process was 3.5 nm and width change -3.5 nm for a 1 Hz scanning frequency. Comparison between distortions without considering blurring effect and distortions considering blurring effect was offered. The effect of scanning frequency on printed pattern distortion and width change was also presented. (C) 1998 American Vacuum Society.