THE ROLE OF THE RESIDUAL SOLVENT FOR CHEMICAL AMPLIFICATION RESISTS

The role of the residual solvent for chemical amplification resists has been investigated. The validity of a model that the mobility of the acid catalyst is governed by the residual solvent assumed to act as a reaction medium is discussed. It has been found that the optimization of the prebake conditions can provide a high resolution without sacrificing the sensitivity. The change in the residual solvent content which is fixed by the prebake conditions has also been found to be a reversible process from the experimental results of a solvent vapor treatment. The optimum post-exposure bake (PEB) conditions which govern the lithographic properties of the resist can be concluded to be strongly dependent on the residual solvent content of the resist film.