以往有許多研究利用奈米壓印微影技術(Nanoimprint Lithography)製作週期性矩形溝槽結構，並對液晶分子進行配向，但矩形溝槽結構無法使配向的液晶分子具有預傾角條件，以致於在電壓操作下產生液晶分子方向分佈之不連續性缺陷，如錯向線。
本實驗利用奈米壓印微影技術，製作高深寬比軟模並利用其壓印挫曲(Buckling)的特性，產生週期性楔形溝槽結構，在所製作結構之表面塗佈monoglycidyl ether-terminated PDMS或垂直配向聚醯亞胺(Polyimide)等兩種材料，觀察其對負型向列型液晶的垂直配向效果。相較於週期性矩形結構對液晶的配向效果，週期性楔形結構已大幅地減少錯向線的發生。另外，我們也利用電子束微影製作不同週期和高度的楔形結構用於液晶配向，其定性結果顯示當結構的週期變小或是高度變高時，對施加電壓的垂直排列負型液晶盒，液晶分子方向很容易沿著溝槽方向排列，這趨勢與Berreman的溝槽配向理論是一致的。

In this study, we use nano-imprint lithography(NIL) to produce high aspect ratio soft stamp, and make it buckle while imprinting to generate periodic wedge groove structures. After that, we let the structures coated by two different vertical alignment layer, monoglycidyl ether-terminated PDMS and polyimide. And observe their vertical alignments to liquid crystals (LCs) with negative dielectric anisotropy. We find out that the liquid crystal cells with wedge structures can obviously reduce the disclination lines compared to rectangular structures. In addition, we produce wedge structures with different pitches and heights by electron beam lithography(E-beam Lithography). The results show that when the pitch gets smaller or height gets larger. The anchoring force of groove direction will become larger after we apply the voltage, so the LCs will prefer to align in the groove direction. And the results are consistent with the Berreman’s theory.

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