Surface reformation on solution-derived zinc oxide films for liquid crystal systems via ion-beam irradiation

Abstract

We investigated solution-derived ZnO films as liquid crystal (LC) alignment layers via ion-beam (IB) irradiation. Solution processing was adopted to replace the sputtering method for the deposition of ZnO films as LC alignment layers. Uniform and homogeneous LC alignment was achieved, and a highperformance LC system was achieved using these substrates. X-ray photoelectron spectroscopy (XPS) analysis showed that surface reformation of ZnO films by annealing and IB irradiation affects the uniformity of the LC alignment and allows control of the pretilt angle. Superior electro-optical (EO) characteristics of twisted nematic-LC cells constructed with IB-irradiated ZnO films were observed, which indicates that the proposed solution-derived ZnO films have strong potential for use in the production of advanced LC displays.

Solution-Driven Imprinting Lithography of Sol–Gel ZnO Thin Films for Liquid Crystal Display

“…The V – T characteristic is shown in Figure a, and the superior performance of the TN mode was obtained for nanopatterned ZnO with the threshold voltage of 0.7 V, which is defined as the applied voltage at the transmittance of 90%, as compared with the conventional TN mode with the rubbed PI thin film of around 2 V. Since the ZnO has large dielectric constant, LC cells can be operated with a reduced applying voltage. In our laboratory, the reduced V – T characteristics of LC cells fabricated with the ZnO thin film of 1.5 V were previously reported . However, the enhanced threshold voltage of 0.9 V was obtained for the LC cell based on the nanopatterned ZnO film.…”

“…In our laboratory, the reduced V−T characteristics of LC cells fabricated with the ZnO thin film of 1.5 V were previously reported. 29 However, the enhanced threshold voltage of 0.9 V was obtained for the LC cell based on the nanopatterned ZnO film. As shown in Figure 8, we observe the electric field distribution over the alignment film mounted on the LC cell under an applied voltage of 5 V. Figure 8a−c describes the electric field magnitude over PI, ZnO, and nanopatterned ZnO deposited on the ITO glass from side views, respectively.…”

A solution-derived bismuth aluminum gallium tin oxide film constructed by a brush coating method for spontaneous liquid crystal alignment

“…1–3 Based on their unique characteristics, LC devices and LC displays (LCDs) play important roles in the advancement and development of the electronic and display industries, due to their long-term durability, excellent resolution, and good electro-optical (EO) performances such as a fast response time (RT) and a low operating voltage, which result in low power consumption. 4–7 To ensure high performance, uniform LC alignment is considered as an important criterion. 8,9 The LC alignment property is affected by the alignment layer property as well as interactions between the LC and alignment layers via physicochemical processes.…”

Physicochemically modified anisotropic polyacrylamide thin film via ion‐beam treatment for liquid crystal system

“…Especially, IB treatment of a polymer surface selectively destroys unfavorably aligned atomic rings within the film's random polymer network, which promotes uniform LC alignment. [ 17 ]…”