Controlled Nanometer-Scale Surface Roughening and Its Effect on the Ordering and Stability of Liquid-Crystalline Polymer Films

Control over surface texture in thin film production is necessary for preparing smooth films (e.g., for optical surfaces), but also where some roughening of the surface is required (e.g., patterning for liquid-crystalline display devices). These authors have found a way to control nanoscale roughening by adsorbing negatively charged colloidal silica particles onto a positively charged polyelectrolyte preadsorbed onto a silicon wafer. Using this method, model surfaces have been prepared which are then substrates for liquid-crystalline polymers. The properties of these films (surface ordering and film stability) are compared with their smooth counterparts.