Evolution of Morphology in the Process of Growth of Island Poly(p-xylylene) Films Obtained by Vapor Deposition Polymerization

Abstract

Using atomic force microscopy, the evolution of the morphology of island poly(p-xylene) films formed on silicon substrates by vapor deposition polymerization at two deposition temperatures of +23 and 0°C and a fixed monomer flow is studied. The dependences of the surface coverage, the effective thickness of the island coating, and the density and average size of the polymer islands on the deposition time are investigated. Within the framework of the dynamic scaling theory, the size distribution of islands and the size distribution of their capture zones are analyzed. It is shown that the observed features of the evolution of the morphology of island poly(p-xylylene) films cannot be fully described in the framework of classical models based on diffusion-limited aggregation. However, they can be explained by the reversibility of aggregation, which is a specific feature of the polymeric nature of the island coatings being formed.