Optimization of Low-Energy Electron Beam Proximity Lithography Stencil Mask Structure Factors by Monte Carlo Simulation

Low-energy electron beam (e-beam) proximity lithography (LEEPL) is a notable next-generation lithography (NGL) technology. This study was performed to search for the most optimized structure of the LEEPL mask. The acceleration voltage of the e-beam and the angle of the pattern wall were taken as variables for our simulation. We calculated the energy and the coordinate of each electron with various possible combinations of these variables. Using this procedure, the count and angular distribution of electrons transmitted through a Si mask were analyzed. For the 50-nm-linewidth processing, the dependencies of the electron count distribution and the electron angular distribution on the pattern wall angle were very high in the case of using relatively high acceleration voltage such as higher than 2 keV.