The influence of the properties of the substrate's surface on the alignment of a discotic liquid crystal

The influence of the substrate's structure on the orientation of a discotic liquid crystal in columnar phase has been investigated using polarised FTIR spectroscopy, scanning electron microscopy and white light interferometry. The amorphous Si and different cuts of polycrystalline ZnSe windows are used in the present study. The cuts of ZnSe are made parallel and perpendicular to the surface of deposition. Pure Si windows and those coated by nylon 6/6 and GeO layer at oblique evaporation are used for these investigations. The role of the easy direction of orientation and the topology of the surface on the alignment of discotic liquid crystals is discussed.