Ultrathin films of homeotropically aligned columnar liquid crystals on indium tin oxide electrodes

Abstract

We report the achievement of very thin films (thickness of about 50nm) of thermotropic columnar liquid crystal in homeotropic (columns normal to the interface) orientation on indium tin oxide (ITO) electrodes. The face-on alignment of the discotic compound has been obtained by thermal annealing without any intermediate coating between the mesophase and the ITO substrate. Such a columnar mesophase alignment is thus shown on a substrate of technological interest in open supported thin film reaching the thickness range suitable for organic photovoltaic devices.