Photolithography and Photochemical Reaction of Copolymer Containing Anthracene in Langmuir-Blodgett Films

Abstract

A series of copolymer containing photoactive anthracene group, poly(N-dodecylmeth- acrylamide-co-anthrylmethylacrylate) p(DDMA-co-AnMA) were synthesized. Their molecular arrangement and photolithographic properties in Langmuir–Blodgett (LB) films were investigated. The copolymer p(DDMA-co-AnMA) could form stable monolayer at air/water interface and could be transferred onto solid supports, giving Y-type uniform LB films. The result showed that the irradiation with difference light wavelength leaded to changes of copolymer LB films in their chemical structure, concerning only the anthracence unit. When irradiated at 248 nm, the anthracene acted as photodecomposition group because of the peroxides. On the other hand, the main photoreaction induced by 365 nm is dimerization of anthracene. As a result, posotive-tone and negative-tone pattern could get by choosing a suittable irradiation light wavelength. Etching resistance of p(DDMA-AnMA) LB films was also investigated in a nanometer regime permitting etching of gold.