EO Characteristics of Fringe-field Switching LCD on a-C:H Thin Films Using the UV Alignment Method

Abstract

We studied the nematic liquid crystal (NLC) aligning capabilities and electro-optic (EO) performance of fringe-field switching (FFS)-LCD using the Ultraviolet (UV) alignment method on a a-C:H thin film was deposited by an rf magnetron sputtering technique at room temperature. A good LC alignment by UV exposure on the a-C:H thin film was achieved. The LC pretilt angle on the a-C:H thin film is higher that on Diamond Like Carbon (DLC) thin film. It is considered that generation of pretilt angle increases due to increasing UV exposure generated the destruction of oriented rings of atoms related to LC alignment on inorganic thin films containing many C─H bonding. The Electro-optical (EO) characteristics of the UV aligned FFS-LCD with obliquely UV exposure on the a-C:H thin film are almost the same as that of the rubbing aligned FFS-LCD on the PI surface. It is considered that strong UV energy gives rise to enough LC aligning capability on the a-C:H thin film.