Inorganic Layer for Homogeneously Aligned Crystals Using Ion Beam Irradiation

Abstract

The authors introduce variable liquid crystal (LC) properties via ion beam (IB) irradiation on the ZrO₂ layers. A uniform LC alignment characteristic was achieved on the ZrO₂ thin film, and the pretilt angle was about 1.2°. We have shown that the pretilt angle can be controlled by changing ion beam parameters, such as the ion beam energy, the angle of incidence, and the irradiation time. The low pretilt angle for the nematic liquid crystal (NLC) on the ZrO₂ thin film treated by ion beam irradiation could be adopted in planer alignment LCD liquid crystal display (LCD) applications as in-plane switching and fringe-field switching modes. The thermal stability of the ZrO₂ thin film was sustained until 210°C. We also have shown that a liquid crystal cell aligned homogeneously by the ion beam irradiation exhibits the voltage-transmittance curve similar to that of a rubbed polyimide cell.

Keywords:

• Liquid crystal alignment
• ZrO₂ thin film
• Ion beam irradiation
• Pretilt angle

Acknowledgment

This research was supported by the MKE (The Ministry of Knowledge Economy), Korea under the ITRC (Information Technology Research Center) Support program supervised by the NIPA (National IT Industry Promotion Agency) (NIPA-2009-C1090-0902-0018).