利用光纖式原子力顯微鏡製作微小液晶配向區之研究

Abstract

本研究主要探討利用光纖式原子力顯微鏡在polyimide液晶配向膜上製作出微小的液晶配向區域，以及觀察對於不同處理方式的polyimide表面。從實驗中得知：(1)同樣的磨刷在不同的表面上所造成的配向效果不同。(2)從光纖式AFM表面影像中可知不同磨刷強度所造成polyimide的形變有所不同。(3)成功地以光纖探針製作出不同區域大小、相對位置的微小液晶配向區域，而且重複越多次的探針刮劃動作，其配向效果越好。(4)定向磨刷所造成液晶分子排列的主要原因是配向膜高分子鏈的旋轉重排，而不是磨刷所造成的溝槽。

In this study, we use atomic force microscope( AFM ) with fiber probing tip to align liquid crystal in micron-size area by polyimide surface modification. We also use AFM to examine different treated polyimide films. We have four conclusions. (1) The same rubbing strength causes different alignment effects on different surfaces. (2) From AFM images, we observe polyimide surface deformation increases with rubbing strength. (3) We successfully align liquid crystal in micron-size areas with different sizes and relative positions. The more times fiber tip modifies, the better alignment we can get. (4) The rubbing-induced polymeric chain alignment is the major effect in aligning liquid crystal molecules.