Photodegradable polymer LB films for nano-lithographic imaging techniques

A new type of polymer Langmuir-Blodgett (LB) films composed of N-dodecylacr ylamide (DDA), which is known to form a stable monolayer, and a photodegrad able monomer, tert-butyl-4-vinylphenyl carbonate (tBVPC), were prepared wit h the aim of developing a novel thin-film positive-tone resist. The copolym er [p(DDA-tBVPC)] could form a stable, condensed monolayer, even at high co mpositions of tBVPC (53 mol.%), and the monolayer could be successfully tra nsferred onto solid supports, such as quartz, glass, and silicon slides, gi ving Y-type uniform LB films. The polymer LB films could be efficiently dec omposed by deep UV irradiation, and after development with alkaline solutio n, a clear positive tone pattern with a line width of 0.75 mum, which is th e highest resolution of the photomask employed, was visible. Moreover, it w as found that these copolymer LB films with nm thickness show high resistan ce performance to an etching process. These fascinating features of the cop olymer LB films show them to be potential candidates as key materials in na no-lithography. (C) 2001 Elsevier Science B.V. All rights reserved.