Optical proximity correction by grey tone photolithography
Cui Z., Du J., Huang Q., Su J., Guo Y.
A new approach to optical proximity correction in VLSI photolithography has been proposed. Instead of changing feature dimension or adding serifs, the mask feature itself has been coded in different grey tone levels at different parts of the feature, based on the analysis of aerial image. Improvement on proximity effect is demonstrated by computer simulation and confirmed by experiment.