Fullerene-derivative nanocomposite resist for nanometer pattern fabrication

A nanocomposite resist system that incorporates a fullerene derivative into a conventional positive-type electron-beam resist, ZEP520, is examined. Be cause of the enhanced solubility of the derivative, the system exhibits a m inimal decrease of sensitivity even at an incorporation content of 50 wt% a nd enables the fabrication of 50 nm patterns with a line dose of 0.39 nC/cm . At higher contents, however, the derivative is not as effective as fuller ene C-60 or C-70 in improving dry-etching resistance because of the aggrega tion of the derivative molecules, which is probably due to the uniqueness o f the derivative used and will be avoided by appropriate molecular design.