The control of thin film morphology by the interplay of dewetting, phase separation and microphase separation

In thin film geometry, the interplay between dewetting and phase separation or microphase separation controls the morphology of the polymeric structures resulting on a solid support. For the model system of polystyrene, polyparamethylstyrene and the diblock copolymer of the two homopolymers, the regime of ultrathin films is addressed experimentally. Evolving structures are probed with real and reciprocal space analysis techniques such as the optical microscopy, phase measuring interference microscopy, scanning force microscopy, neutron or x-ray reflectivity and grazing incidence small angle neutron or x-ray scattering approaches. The effective interface potential of the solid support is tuned by means of a change of the silicon substrate coating. Coating layers of silicon oxide, polyamide and polyimide are under investigation. A power law behaviour describing the most prominent in-plane length as a function of the initially prepared film thickness is observed. All reported structures have been prepared on large scale surfaces, such as typical Si wafers with 100 mm diameter.