Influence on digital photolithography intensity by collimated Gaussian beam

摘要

The theory of Gaussian beam expansion and collimation has been investigated. Based on Collins diffraction integral and matrix decomposition method, the propagation characteristics of Gaussian beam passing through beam expansion and collimation system is analyzed. The corresponding mathematical model is established. Simulations results indicate that the optical field distribution behind beam expansion and collimation system is still with Gaussian attribute. Then we demonstrate the optical field of beam with Gaussian attribute passing through 2-D sinusoidal grating. Finally, the step depth error of binary element is evaluated under illumination of Gaussian beam. The theoretical analysis and simulation results have reference for the establishment of digital lithography model and the optimization of beam expansion and collimation system.