Rapid fabrication of grating of variable submicron line width based on digital micromirror devices collaborative modulation lithography

Abstract

The wide application of grating in engineering puts forward higher requirements for fabrication efficiency and precision. Maskless lithography based on digital micromirror device (DMD) is considered to be a promising technology with the advantages of high efficiency, low cost, and good flexibility. However, DMD-based digital lithography has been implemented mostly for micron-scale fabrication, which restricts its application to microstructures with submicron feature sizes. In this study, to realize the rapid fabrication of the grating of variable submicron line width, we adopt two misaligned DMDs to collaboratively modulate the exposure dose. By flexibly adjusting the misalignment parameter and the feature size parameter of the original grating mask, the gratings of variable micrometer and submicron line width are fabricated. We also evaluate the fabrication results by the photomicrographs and the optical diffraction modulation effects of the gratings. DMDs collaborative modulation lithography may be a feasible solution for DMD-based digital lithography, which can balance the lithography resolution, the fabrication efficiency and the manufacturing cost.