Electron beam lithography simulation for high resolution and high-density patterns

A fast simulator for electron beam lithography, called SELID (TM), is appli ed for the simulation and prediction of the resist profile of high-resoluti on patterns in the case of homogeneous and multilayer substrates. For expos ure simulation, an analytical solution based on the Boltzmann transport equ ation (where all important scattering phenomena have been taken into accoun t) for a wide range of e-beam energies is used. The case of substrates cons isting of more than one layer (multilayer) is considered in depth as it is of great importance in e-beam patterning. By combining the energy depositio n data from simulation with analytical functions describing the resist deve lopment (for the conventional positive-resist PMMA), complete simulation of dense layouts in the sub-quarter-micron range has been carried out. Additi onally, the simulation results are compared with experimental ones for dens e patterns in the sub-quarter-micron region. By using SELID (TM), forecast of resist profile with considerable accuracy for a wide range of resists, s ubstrates and energies is possible, reducing in that way the cost of proces s development. Additionally, proximity effect parameters are extracted easi ly for use in any proximity correction package. (C) 2001 Elsevier Science L td. All rights reserved.