Process techniques for improving performance of positive tone silylation

Two approaches that control the overflow of silylated material that can occur subsequent to surface imaging of acid-hardened resists are introduced. Treatment of the resist surface with a cross-linking agent [bis(dimethylamino)dimethylsilane] prior to silylation can produce a surface layer with the physical integrity to constrain silylated material. Alternatively, the unexposed areas of the resist may be partially removed by development with a basic solution. The surface depressions thus produced allow volume expansion to occur during silylation without causing overflow.