Swelling Analysis of Methacrylate Polymers in Aqueous Alkaline Developer

The dissolution behavior of a methacrylate polymer was analyzed by the Quartz Crystal Microbalance (QCM) method in order to clarify the dissolution mechanism of ArF resists and control thereof. The QCM analysis provides information on the dissolution rate and the swelling rate of the polymer film by measuring the weight change in polymer films during the development. Poly(isobornylmethacrylate-co-methacrylic acid)s were studied as a model polymer for the resist in ArF excimer laser lithography by the QCM method. It was found that an increase in the bake temperature for the film preparation decreases the dissolution rates and the swelling rates in an alkaline solution, that an increase in methacrylic acid units produces the characteristic surface and interface layers which do not depend upon the bake temperature, and that an increase in isobornylmethacrylate units produces swelling during the development.