Control of surface morphology by the interplay between phase separation and dewetting

By control of phase separation and dewetting of thin blend films of weakly incompatible polymers, particular surface patterns may be generated. These patterns cover a typical height scale from 0.3 nm to 300 nm and most promin ent in-plane length scale from 0.1 mu m to 100 mu m. Characteristic feature s are holes, regular continuous structures, and drops of these sizes. In ad dition, conformal rough surfaces with a morphology dominated by one of the underlying substrates can be prepared. The surface morphology was investiga ted with scanning force microscopy (SFM), while the interface correlation w as measured with diffuse X-ray scattering. Both methods together yield a to pological description of the examined samples. Observed morphologies origin ated from phase separation of the thin blend film and from the dewetting of one blend component on top of a continuous film formed by the other compon ent.