부산대학교 도서관

Resist variability is one of the challenges that must to be solved in extreme UV lithography. One of the root causes of the resist roughness are the mask contributions. Three different effects may plays a non-negligible role: mask pattern roughness transfer --- or mask line edge roughness, speckle effects caused by mask surface roughness, and mask layout which causes local flare amplification at wafer level. In this paper, mask contributions to the pattern variability are individually assessed experimentally and via stochastic simulations for both lines/spaces and contact holes. It was found that the predominant effect is the mask layout, while the speckle contribution is barely detectable.