Simulation of electron beam exposure of submicron patterns

Publisher Website
Google Scholar
Abstract
Analytical and Monte Carlo electron beam radial exposure distributions (REDs) are compared for accuracy in predicting proximity effects in submicron lithographic patterns. A proximity effect simulation tool (PRESTO) has been developed to convolve the desired pattern with the RED obtained from a companion Monte Carlo program for the simulation of electron energy loss (SEEL) or an empirical RED which is an analytical fit to experimental results. Together, SEEL and PRESTO are shown to simulate the electron beam exposure of submicron size patterns using a focused Gaussian electron beam system. PRESTO generates the electron distribution for the pattern by simulating the exposure of the resist for each pixel. Once the energy distribution has been determined equienergy density contours for the exposure of a given shape can be plotted. The ability of PRESTO and SEEL to accurately simulate the exposure of patterns with 0.25 μm design rules is demonstrated. Comparisons are made of the simulation results obtained when double Gaussian, triple Gaussian and SEEL approximations are used for the REDs. We also show that these two programs can be used to evaluate the sensitivity of the radial exposure distribution and proximity effects for multilevel substrates, for varying topography, and for different exposure conditions.

This publication has 0 references indexed in Scilit: