Nano-domains formation on photoalignment thin film by self-organized dewetting

A novel discontinuous photoalignment surface with nano-domains for liquid crystal is developed. The formation of the discontinuous structure is created by self-organized dewetting, which is regarded as one of the most promising bottom-up approaches to fabricate nano-structure. Different dewetting conditions, such as surface roughness, thickness and viscosity, have been investigated. Such discontinuous photoalignment layer can be fabricated on top of another continuous alignment layer to form a new kind of heterogeneous nano-structured alignment surface - stacked alignment layers. This heterogeneous alignment surface can be used to produce arbitrary pretilt angles for the liquid crystal display. Simulation model has been built to understand the dewetting mechanism. Experiments using photo-aligned and photo-polymerisable polymer have been done to verify the dewetting theory. The produced stacked alignment layers are proved to be robust. Moreover, the dewetting processing is a fully controllable process and is compatible with existing manufacturing techniques.