Studies of the Directional Property on Rubbed Alignment Films by Rubbing Condition

Abstract

The near-edge X-ray absorption fine structure(NEXAFS) and its polarization dependence on Carbon(C) K-edge, is used to obtain information on the molecular orientation at the polyimide(PI) surface. Rubbed PI alignment layer was controlled the pile contact impression and stage speed. We could estimate the alignment angle α of the molecules with the surface normal of the PI molecules through the intensity change of C˭C π* in NEXAFS C K-edge spectrum, depending on the photon incident angle θ = 20°, 55° and 90°. As increasing the depth of the pile contact, the angle α was linearly decreased. The stage speed dependency was shown an irregular pattern.

Keywords:

• Alignment
• NEXAFS
• polyimide
• rubbing

Acknowledgments

The experiments at PLS were supported in part by MEST and POSTECH. This research was supported by the LG Display through the grant of 4.0003497.01 and National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (2009-0087138).