Studies of photosensitive alignment layer based on ladder-like polysilsequioxane liquid-crystal devices using atomic force microscopy/force curve

Atomic force microscopy (AFM)/force curve measurements were used to study the photochemical process of UV-treated (0, 10, 20, 30 and 60 min) organic thin films that were prepared from azobenzene and cinnamate side-chain co-grafted ladder-like polysilsequioxanes (LPS). The morphological data of the thin films describe the changing process on the surface of the thin film. The statistical results of the adhesion force of the thin films further demonstrate the intermolecular characteristics of the thin films. A photosensitive thin film after UV exposure for 20 min would be a better material with a preferred orientation that can be used to make liquid-crystal devices. Copyright (C) 2003 John Wiley Sons, Ltd.