Deposition of oriented polymer films for liquid crystal alignment by pulsed laser ablation

Well oriented polyethylene (PE), polytetrafluoroethylene (PTFE), nylon and polyimide films were prepared on glasses coated with indium tin oxide (ITO) and on Si(100) substrates by the pulsed laser ablation technique with a laser fluence from 1.3 J/cm(2) to 3.0 J/cm(2) at a vacuum of 10(-7) Torr. The films were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectrum and atomic force microscopy (AFM). The nematic liquid crystal 4'-n-pentyl-4-cyano-biphenyl (5CB) is used to display the orientation features of the above prepared films. Based on the experiments, a picture is presented about the formation of the polymer films. It is expected that the as-deposited highly oriented polymer films by laser ablation will find various applications in integrated optics and liquid crystal displays.