Method for improving illumination uniformity of a digital mask-less scanning lithography system

Abstract

To face the challenge of the highly complex illumination system resulting in extremely high hardware costs in mask and mask-less lithography, we propose a novel, simple, and low-cost DMD-based mask-less lithography method to improve illumination uniformity during continuous scanning patterning by using oblique scanning processes and DMD modulation. By loading a digital mask generated by DMD modulation and selectively turning off micromirror arrays on the DMD surface during oblique scanning, the light intensity distribution within the scanning exposure field is reconfigured, achieving 96 % illumination uniformity. Furthermore, the dimensional difference was reduced from 2.5 μm to 0.3 μm for a two-dimensional grating on a 3-inch substrate. Finally, a novel DMD-based mask-less lithography method was explored with significant improvements in both cost efficiency and patterning precision, making it a promising solution for future lithographic applications.