Sensitivity Characteristics of Positive and Negative Resists at 200 kV Electron-Beam Lithography

Abstract
The contrast curve of positive and negative electron-beam resists such as polymethylmethacrylate (PMMA), ZEP520A, and hydrogen silsesquioxane (HSQ) at 200 kV electron-beam was estimated by using continuous slow down approximation (CSDA) model with both non-relativistic and relativistic Bethe stopping power. Experimental results show that simple CSDA model well explains the overall response of these various electron-beam resists to high energy electron-beam only if we use the relativistic Bethe stopping power. The difference between non-relativistic and relativistic Bethe stopping power is discussed.