Molecular Resists Equipped with Fluorinated Aromatic Units for Electron-beam and Extreme UV Lithography

In this presentation, we will show our efforts for the discovery of high-performance imaging reactions based on fluorine and radical chemistry working under high-energy radiation. Prior to this study, we have reported molecular resists equipped with rather flexible perfluorinated alkyl ether (PFAE) chains and their imaging behavior as negative-tone resists under electron beam irradiation. In this study, we turned our attention to another fluorinated unit, fluorinated aromatic compounds, possessing structural rigidity that we believe contributes to achieving improved patterning capabilities. Successful coupling reactions between a phenolic resist core and fluorinated arenes provided fluorinated molecular resists, which we evaluated in terms of imaging behavior under e-beam and EUV lithographic conditions. The solubility of their thin films was decreased by the high-energy radiation; thus, negative-tone patterns down to 30 nm half-pitch could be obtained after development in fluorous solvents.