Nonlinear Optical Properties and Phase Structure of VOPc Thin Film Prepared on Polyimide Substrate

Abstract

Vanadyl-phthalocyanine (VOPc) thin films were prepared by an organic molecular beam deposition (OMBD) on Polyimide (PI) substrate. The morphologies and nonlinear optical properties of VOPc films were investigated with VIS/UV spectra and the third harmonic (TH) intensity measured by Marker fringe. The VOPc films prepared with different substrate temperatures (25°C and 150°C) showed the Phase structures of Phase I and II at 25°C, and Phase III at 150°C. The packing density of VOPc thin film having Phase III is much higher than that of Phase I and Phase II. Therefore, the VOPc film prepared at 150°C has higher packing density than that at 25°C. The VOPc films prepared on PI film charged with and no charged without corona charging were also investigated from VIS/UV spectra and TH intensity. The third harmonic intensity of the VOPc thin film enhances with the packing density in VOPc thin film. The third optical susceptibility (χ⁽³⁾) estimated from the peak of TH intensity of the VOPc thin film prepared on the PI film charged with corona charging is about 2.3×10^-9 esu.