Nematic liquid crystal alignment on the ion beam-exposed ZnO film

• Published in: Thin solid films 2010-11, Vol.519 (2), p.885-889
• Main Authors: Hwang, Soo-Won, Seo, Joo-Hong, Yoon, Tae-Hoon, Kim, Jae Chang
• Format: Article
• Language: English
• Subjects: Alignment; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Deposition; Deposition by sputtering; Electrical properties of specific thin films; Electrical resistivity; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Groove pattern; Ion beam treatment; Ion beams; Liquid crystal; Liquid crystals; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Nematic; Physics; Structure and morphology; thickness; Structure of solids and liquids; crystallography; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Transmittance; Zinc oxide
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2010.08.105

This paper investigates the nematic liquid crystal (NLC) alignment on ion beam-exposed zinc oxide (ZnO) films. The ZnO films are deposited by a radio frequency magnetron sputtering. During the deposition of ZnO film, we supplied sufficient oxygen gas for high resistivity and transmittance. The deposited films show a high transmittance of over 90% and high resistivity of over 10 10 Ω cm. The ZnO films show a high deposition rate of 26.7 Å/min. Images obtained via scanning electron microscopy of the ZnO film surfaces, before and after the ion beam exposure, show that groove patterns are formed being to be parallel to the ion beam exposure direction. LC cells are fabricated with the ion beam-exposed ZnO films. The NLC molecules align parallel to the ion beam exposure direction. The electro-optic and response characteristics of fabricated cells show the possibility of application to liquid crystal displays.