Submicron liquid crystal pixels on a nanopatterned indium tin oxide surface

Abstract

We have prepared a grooved indium tin oxide (ITO) surface with groove widths of ∼40–90 nm and a variable groove separation up to 36 μm using atomic force microscopy nanolithography. Twisted nematic pixels with 4-n-pentyl-4-cyanobiphenly (5CB) liquid crystal were prepared using a rubbed polyimide counter plate. The 5CB molecules align along the direction of the grooves, but no pretilt angle was observed on the ITO surface. The surface anchoring energy appeared not to depend on the groove separation nor on the scan force. The lateral correlation length of 5CB on ITO was measured to be 2.2 μm. If a grooved surface is scanned in another direction, liquid crystal molecules follow the direction of the last scan.