Liquid Crystal Alignment on Thin Organic Films Deposited in a Low Pressure Plasma Enhanced CVD Reactor

Abstract

The application of a low pressure plasma enhanced chemical vapor deposition (PECVD) system is considered for the deposition of thin carbon films with alignment properties for liquid crystals (LC). The original electrode configuration induces directional planar alignment properties on deposited films, and makes possible to fabricate alignment layer in a one step process. To evaluate the LC alignment properties LC cells are assembled from substrates with deposited carbon films and observed in a polarizing optical microscope. Directional ion bombardment induced by the electrode configuration is considered to be the cause of the observed LC molecules alignment. The simultaneous deposition and ion bombardment processes induce a favorable condition for depositing carbon films with anisotropic properties. Experimental SectionBorosilicate glass plates (2 Â 2 cm 2 and 1 mm thick) are placed on the power electrode and used as substrates to deposit thin films in a