Photolithographic properties of ultrathin polymer Langmuir–Blodgett films containing anthracene moieties

Abstract

This study investigated the unique photolithographic properties of poly(N-neopentyl methacrylamide-co-9-anthrylmethyl methacrylate) (p(nPMA-AMMA)) ultrathin films prepared by the Langmuir–Blodgett (LB) technique. The copolymer forms a stable monolayer on a water surface and LB films with any desired number of layers. The nPMA group in the LB film acts as a photodecomposition group under irradiation at 254 nm. On the other hand, photodimerization occurred between anthracene groups under irradiation at 365 nm. Consequently, positive-tone and negative-tone patterns were printed on a silicon wafer by choosing a suitable irradiation light wavelength. Etching resistance of p(nPMA-AMMA) LB films was also investigated in a nanometer regime permitting etching of gold or copper films.