Optimization design of immersion magnetic lenses in projection electron beam lithography

摘要

In this paper, a novel immersion magnetic lens used for projection electron beam lithography is optimized by Powell method. The optimized structure of an immersion magnetic lens can be reached with a criterion of minimum objective parameter, which is the value of curvilinear axial astigmatism in the present paper. The results show that axial astigmatism is decreased from 243 nanometer to 50 nanometer after optimization. It can be seen that the Powell method is suitable for the optimization design of immersion magnetic lenses. [References: 10]