Origins of nanostructure in amorphous polymer coatings via matrix assisted pulsed laser evaporation

We investigate the nanostructure of sub-monolayer and monolayer amorphous polymer films deposited via Matrix Assisted Pulsed Laser Evaporation (MAPLE). The structure is quantified by analyzing the size distribution of polymer nanoglobules as a function of deposition parameters: time and polymer concentration. Two deposition regimes are observed in the early stages of MAPLE deposition, with a transition at a critical time. The observed distribution of nanoglobule sizes that is present after the critical time agrees well with prior molecular dynamics simulations of the MAPLE process. We discuss the mechanism of nanostructured coatings within the framework of the Zhigilei model. (C) 2013 AIP Publishing LLC.