Planer alignment of polycrystalline thin films using rod-like liquid crystals and its application for vertical devices

Abstract

We have investigated to fabricate the planar aligned polycrystalline thin films using liquid crystal phase and made vertical device with the planar aligned thin films. We find new polymer, Poly(methacrylic acid) (PMAA), which shows higher glass transition temperature, as over coated layer. Spin-coated thin films of the liquid crystalline phenyl-naphthalene derivative with PMAA over coated layer and heated in SmA phase give us reoriented thin films from vertical to planar alignments with high reliability. In the planar aligned polycrystalline thin films with varied thickness from about 10 nm to 50 nm, all films show reorientation from vertical to planar alignments. We fabricate organic light emitting diodes with the planar aligned thin films.