在平面顯示器中控制液晶配向是一項相當重要的技術，一般液晶顯示器的配向膜材料為聚醯亞胺(polyimide），以絨毛布摩擦後來排列液晶分子，但是有許多相當嚴重問題會產生在配向層的塗佈與機器的摩擦過程中，因此有相當多針對製程或材料上提出改進的研究，在配向的技術上，又以非接觸配向的方式，是最有機會運用在次一世代高解析度的大尺寸液晶顯示器上，近年來有許多運用在配向層的材料，例如聚醯亞胺（polyimide）、類鑽碳（diamond-like carbon）與氮化矽（SiNx）等材料，利用離子束轟擊配向膜的方式配向液晶，且陸陸續續有成功的成果發表。

　　而在我們的實驗中可以發現，利用適當能量的氬離子轟擊二氧化矽薄膜，也能改變薄膜表面的結構，對液晶分子產生非等向性的作用力，因而造成液晶分子做有次序性的排列，當我們使用氬氣離子能量為500電子伏特，以與基板法線夾 ~ 的角度入射，轟擊二氧化矽薄膜表面，經量測其預傾角，可以得到 的變化量，當把樣品間隙改為6μm時，做成扭曲向列型液晶（Twist Nematic Liquid Crystal）盒時，在入射角度大於 的樣品，經量測其穿透率對電壓關係與對比度上，均有不錯的表現，並且可以得到快速的反應時間。

　Controlling the liquid crystalline (LC) alignment is certainly the most important technology in flat panel display technology. In general, polyimide is used in LC cells as the material to align LC by employing a mechanical rubbing technique. Because of various problems related to the polymer coating and the mechanical rubbing processes, many researches have been done on the development of improved methods and materials. Plus, a number of alternative alignment techniques have been reported; especially, the non-contact alignment technologies have great potential for future generations of large, high-resolution liquid-crystal displays (LCD). More recently, some alignment materials, i.e. polyimide, diamond-like carbon, and SiNx have been successfully tested by ion-beam alignment method.

　Liquid crystals in our experimental discovery can be aligned on a SiO2 surface bombarded by an appropriate energy and neutral argon ion beam. Also, the pretilt angle of liquid crystals could be varied between 0o and 3.5 degree, by controlling the argon ion beam with energy of 500 eV at an incident angle varying from 0 degree to 85 degree which were measured from the normal of the substrate. Finally, the twist nematic test cell of the cell gap 6 um incorporating SiO2 alignment films exhibited good optical transmission and fast response time when the angle of incident ion beam was greater than 45 degree.

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