溝槽配向定向強度對溫度變化之關係

Abstract

使用半導體微影技術來對液晶進行配向在微機電的應用上有很大的潛力，此技術能在局部的小區域對液晶配向，而傳統的摩擦高分子薄膜進行配向之方法則很難達成。 在本論文中，我們使用反應離子蝕刻的方式來處理玻璃基板之表面，並研究其配向之機制。蝕刻溝槽的週期為4μm，蝕刻時間為一分鐘，並加入含左旋液晶S811的5CB(4`-n-pentyl-4-cyanobiphenyl)，量測在25℃至35℃之間定向強度大小隨溫度變化之關係。由於光學特性的限制，我們使用三種不同波長之雷射光來量測定向強度大小，以期能量出所選擇的溫度區間之數據。我們已觀察到隨著溫度增加，定向強度會穩定地減小。

Utilizing semiconductor lithograph process to align liquid crystals has significant potential application on Microelectromechanical system (MEMS). It can align liquid crystals in a certain small region which the traditional rubbing method is difficult to achieve. In this thesis, we used parallel grooved glass surfaces prepared by reactive ion etch method (RIE) to study the mechanism of liquid crystal alignment. The groove period is 4μm and the time interval being reactive ion etched is one minute. Azimuthal anchoring of 5CB (4`-n-pentyl-4-cyanobiphenyl) with chiral dopant was measured from 25℃ to 35℃. Due to the limitation of the optical characteristics, three lasers in different wavelengths were used in order to obtain the complete data in the chosen temperature range. We have observed a steady decrease in azimuthal anchoring as the temperature increases.