DEPENDENCE OF DISSOLUTION RATE ON PROCESSING AND MOLECULAR PARAMETERS OF RESISTS.

Abstract

This paper explores factors beyond the well known molecular weight and chemical effects on the dissolution kinetics of polymers. Factors controlling solvent mobility in polymeric matrices, such as stereo chemistry (tacticity), processing (heat treatment) and solvent molecular size may affect the dissolution kinetics of polymers far more strongly than factors affecting the equilibrium solubility, e. g. molecular weight of the polymer. It is shown that while the dissolution rate scales to approximately minus 0. 7 power of the polymer molecular weight (P(MMA), it can scale to minus 16 power of the solvent molecular size (propyl to hexyl acetate). Heat treatment of P(MMA) is also shown to change the dissolution rate by several orders of magnitude. The study points to the prime importance of the molecular dynamics of both the polymer and the solvent on the resist dissolution kinetics.