Resist thickness effects on ultra thin HSQ patterning capabilities

This work focuses on the effect of resist thickness on resolution performance of hydrogen silsesquioxane (HSQ) electron beam resist. Contrast, sensitivity, surface morphology and resolution of the formed structures were found to be substantially dependent on film thickness. Method of resist drying in vacuum at room temperature was found to reduce surface roughness of ultra thin HSQ films compared to hot plate drying at 90 °C in air. Results of Monte Carlo simulations of the exposure process are in good agreement with proposed mechanism of sensitivity loss and structure linewidth broadening with increase of resist thickness.