Nano-patterning of a hydrogen silsesquioxane resist with reduced linewidth fluctuations

A new resist system providing small linewidth fluctuation has been developed for nanolithography. Hydrogen silsesquioxane (HSQ) resist used here has a small polymer size because of its three-dimensional framework. This framework reduces the size of aggregates in the resist film which strongly influence linewidth fluctuation of resist patterns. The scission of SiH bonds in HSQ by e-beam leads to the crosslinking required for the nega-patterning. In addition, the application of a TMAH developer realizes higher contrast an less thickness loss. Consequently, 20-nm-wide nega-patterns with a rectangular cross-sectional shape are successfully formed with linewidth fluctuation less than 2 nm.