Open AccessIntensity modulation based optical proximity optimization for the maskless lithography
Author(s) -
Jianghui Liu,
Junbo Liu,
Qingyuan Deng,
J. Feng,
Shaolin Zhou,
Song Hu
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.381503
Subject(s) - maskless lithography , digital micromirror device , optics , lithography , grayscale , materials science , photomask , digital light processing , photolithography , image subtraction , computer science , artificial intelligence , physics , electron beam lithography , image processing , resist , projector , pixel , binary image , nanotechnology , image (mathematics) , layer (electronics)
The undesirable optical proximity effect (OPE) that appeared in the digital micro-mirrors device (DMD) based maskless lithography directly influences the final exposure pattern and decreases the lithography quality. In this manuscript, a convenient method of intensity modulation applied for the maskless lithography is proposed to optimize such an effect. According to the pulse width modulation based image recognition of DMD, we replaced the digital binary mask with a special digital grayscale mask to modulate the UV intensity distribution to be closer to the expectation in a way of point-by-point modification. The exposure result applying the grayscale mask has a better consistency with the design pattern than that for the case in which the original binary mask is used. The effectiveness of this method was analyzed by the image subtraction technique. Experimental data revealed that the matching rate between the exposure pattern and the mask pattern has been improved from 78% to 91%. Besides, more experiments have been conducted to verify the validity of this method for the optical proximity optimization and its potential in the high-fidelity DMD based maskless lithography.