Simulation of resist profiles in single and triple layer electron beam lithography

Abstract

Resist profiles in PMMA are simulated for the case of single and triple layer electron beam lithography. Line width variations and edge slopes are compared in two cases. Improvements in line width variation and edge slopes have been shown to occur after proximity exposure correction. Further in the case of a triple layer by changing the transfer layer from low At No. silicon to high At No. tungsten, the required dose is less due to increased proximity exposure closer to the beam in tungsten. Resist profile simulation of closely spaced line patterns shows that a bridge between the patterns results which is eliminated after proximity exposure correction.