Proximity correction for high CD accuracy and process tolerance

Abstract

Among the most important parameters in direct e-beam writing of ASICs is the control of linewidth. There are mainly two factors which endanger CD control: the proximity effect and topography on the wafer. For best possible CD beneath proximity correction the influence of topography on the linewidth must be respected. This paper presents an extension to the proximity correction package PROXECCO, which is designed to make CD deviations as insensitive as possible to dose errors over an estimated ±20% range. The applied method, printed results and measurements are presented.