Exposure dose control for step-and-scan lithography

Exposure dose control technique in step-and-scan exposure lithography systems is discussed. The dose control principle for step-and-scan system is analyzed in depth. A dose control algorithm is proposed. Measurements of dose accuracy and repeatability are made on an experiment setup. Dose accuracy of 1.37% and dose repeatability of 0.31% are obtained using this dose control technique. Experiment results indicate that this dose control technique meets the requirement of sub-half-micron lithography.