How to fabricate high aspect ratio microstructures with high precision has become a very concerned issue. In this paper, the pattern transfer accuracy of proximity lithography is investigated and the related distortion compensation method is presented. According to partial coherent light theory, the propagation of partial coherent light, which is from an extended quasi-monochronmatic source and transferring through the illumination system, is analyzed. And based on the complex degree of coherence for any two points on mask plane, a mathematical model is constructed to analysis the propagation of mutual intensity from mask to photo-resist and the intensity distribution is attained. With the aerial image of mask pattern, the photo-resist profile is simulated. Then the pattern distortion is investigated, especially on the edges and corners of the profile. And a mask optimization method using genetic algorithm is proposed to improve pattern transfer accuracy. Theoretical model indicates an effective way for resist shape distortion analysis and compensation.

Date Published: 18 May 2009
PDF: 6 pages
Proc. SPIE 7284, 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems, 728405 (18 May 2009);

Published in SPIE Proceedings Vol. 7284:
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems
Sen Han; Masaomi Kameyama; Xiangang Luo, Editor(s)