Ion-beam-irradiated solution-derived tin oxide films for liquid crystal orientation

Abstract

We present the alignment characteristics of liquid crystal (LC) molecules on solution-derived tin(IV) oxide (SnO 2 ) films. Solution processing was used in place of the sputtering method to deposit SnO 2 films as LC alignment layers. The LC molecules on the SnO 2 surfaces could be homogeneously and uniformly aligned by ion-beam (IB) irradiation. X-ray photoelectron spectroscopy (XPS) analysis indicated surface reformation of the SnO 2 films resulting from annealing and that IB irradiation affects the uniform LC orientation. Fast response times of twisted nematic cells constructed with IB-irradiated SnO 2 films were observed, which indicates that the proposed IB-irradiated solution-derived SnO 2 films have considerable potential for use in the production of advanced LC displays.

Effect of Poly(vinylidene fluoride-trifluoroethylene) Film Concentration and Alignment Method upon Liquid Crystal Alignment

“…For manufacturing liquid crystal displays (LCDs), it is essential to use liquid crystal (LC) alignment films that allow uniform and defect-free LC alignment. Various kinds of organic and inorganic materials have been examined for use in LC alignment films, such as polyimide (PI), [1][2][3] polystyrene, 4,5 polydimethylsiloxane, 6 SiO x , [7][8][9] diamond-like carbon, 10,11 Al 2 O 3 , 12 ZnO, 13,14 MgF 2 , 15 SnO 2 , 16 and LaYSrO. 17 Among them, PI is one of the most suitable materials for LC alignment films due to its heat resistance, chemical stability, and mechanical strength.…”

“…10,11 For these reasons, non-contact alternative methods of LC alignment have been investigated such as oblique deposition, 7,8 ultraviolet (UV) photoalignment, 2,[23][24][25] nanoimprint lithography, 26 and ion beam (IB) irradiation. 5,6,[10][11][12][13][14][15][16] Among these alignment methods, IB irradiation can selectively destroy chemical bonding at the alignment film surface, inducing anisotropy.…”