Using KLUP for understanding trends in EUV resist performance

Abstract

Previously we have proposed a resist Figure of Merit KLUP that describes the performance of a resist material for Resolution, Line-Width Roughness and Sensitivity in a single number. In the present work we demonstrate how this approach can be used to understand the effects of film thickness variation and PAG loading on the performance of EUV resist formulations. It is found that lower film thickness tends to decrease the sizing dose and increase LWR. These effects can be quantitatively described with the KLUP theory. Increasing PAG loading for EUV resists increases the probability for a secondary electron to react with a PAG molecule and therefore increases quantum yield and decreases KLUP. Finally the approach is used to compare the relative performance of conventional EUV resists with that of polymer-bound PAG resists. It is found that the latter have potential for improved overall performance and superior LWR results. ©2008CPST.