Electron Beam Lithography Simulation on Homogeneous and Multilayer Substrates

A fast simulator for electron beam lithography, called SELID, is presented and applied in the case of homogeneous and multilayer substrates. For exposure simulation, an analytical solution based on the Boltzmann transport equation is used instead of the Monte Carlo. All important phenomena (forward scattering, backscattering, generation of secondary electrons) have been taken into account for a wide range of e-beam energies. The case of substrates consisting of more than one layer (multilayer) is considered in depth as it is of great importance in e-beam patterning. Results of simulation are compared with experimental ones in the case of single pixel exposures. Additionally, simulation results are compared with experimental ones for isolated and dense patterns in the sub-half-micron range, on conventional positive resist on homogeneous and multilayer substrates. By using SELID, forecast of resist profile with considerable accuracy for a wide range of resists, substrates and energies is possible. Additionally, proximity effect parameters are extracted easily for use in any proximity correction package.