New three dimensional simulator for low energy (similar to 1 keV) electronbeam systems

In this article, we describe the models and the results of a new three dime nsional (3D) lithography simulation programs for low energy (similar to 1 k eV) electron beam systems. Monte Carlo simulation was performed to obtain t he energy intensity distribution in e-beam resists, and the models we have used were tabulated Mott data for elastic scattering, Moller and Vriens cro ss sections for inelastic scattering, and modified Bethe equation plus disc rete energy loss for energy loss. The energy intensity in poly(methyl) meth acrylate was calculated with the exposure simulation program with various p attern shapes. In the development simulation program, the 2D or 3D resist p rofile could be implemented. The ray tracing model and the Neureuther equat ion were used for the development simulation. The simulated developed depth s as a function of energy were compared with experimental results developed by Rishton and Schock. The maximum deviation from the experimental results was 12.4 nm (6%) at 2500 eV, and all the data were within error range. The optimum condition was obtained and the positive and negative resist profil es for 50 nm line and space pattern were realized with our simulation progr am. (C) 1999 American Vacuum Society. [S0734-211X(99)10406-2].