Dewetting of thin block copolymer films

The dewetting of thin films of low molecular weight diblock and triblock co polymers of poly(oxyethylene)/poly(oxybutylene) on silicon has been studied using video microscopy and X-ray reflectivity. Dewetted films were observe d to comprise polygonal domains of polymer droplets, with a domain size of several millimeters. The dewetted films were studied using Xray reflectivit y, which showed that a film of polymer <50 Angstrom thick remains on the su bstrate at the same time as the macroscopic droplets. This suggests that au tophobic dewetting occurred in this system; i.e., a microscopically thin fi lm was in equilibrium with macroscopic droplets. The growth velocity of hol es in the polymer film was found to be constant at a fixed temperature in t he stage of hole growth that could be studied using optical microscopy. The velocity was found to be an exponential function of temperature, (C) 1999 Academic Press.