Abstract
Reflection ellipsometry is applied to characterize the molecular orientation of rubbed polyimide films for LCDs. Larger anisotropic polarization is observed in reflected light than in retardation of transmitted light. Reflection ellipsometry has at most 30 times higher sensitivity than retardation measurement. Effect of rubbing-strength to polyimide film is observed with reflection ellipsometry. It is clarified by analyzing the polarization of reflected light that rubbed polyimide film is composed of a molecular-oriented upper layer and an isotropic lower layer. In my strongest rubbed film, the thickness and tilt angle of principal dielectric axis of the upper layer were determined to be about 13nm and 40°, respectively. Observation indicates clear dependence of tilt angle on rubbing strength. Rubbing-strength dependence was not observed in thickness of molecular orienting layer.
