受外界影響下產生響應而引發的自組裝週期性微奈米結構，經常發生在各向異性的自組裝超分子系統(例如液晶系統)。然而，這些結構的有序性往往是不易控制的。本論文乃研究在膽固醇液晶的平面結構中，施予一平行於螺旋軸之外加電場下於空間中產生類似於正弦波形的二維週期性之Helfrich形變結構，利用於樣品基板上預先製作週期性之一維週期微溝槽結構，研究是否能有效地提升電致二維形變結構之大面積有序性。
實驗結果顯示，當施加外加電場於平面型膽固醇液晶時，產生Helfrich形變之二維網格結構具有局部(微觀尺度)有序而大面積(宏觀尺度)無序之特徵。若在樣品的基板上預先建立週期性的一維週期微溝槽，且微溝槽的週期與膽固醇液晶受電場引致的Helfrich形變產生的二維網格間距匹配時，能有效地控制二維網格微結構變成大面積且有序排列。實驗結果進一步發現，二維網格微結構的大面積有序性與一維週期微溝槽深度有直接關係。另外，本論文亦討論到當一維微溝槽的週期與膽固醇液晶電致二維網格結構週期不匹配時，後者容易受到一維週期微溝槽的影響而產生錯位、差排等現象。此研究成果提升了著名的Helfrich形變現象的可應用性，希冀能進一步達到控制自組裝超分子系統中的週期性微奈米結構，相關研究成果更希望能利於人類的科技進展。

Self-assembled periodic micro/nanostructures triggered by responses to external influences often occur in anisotropic self-assembled supramolecular systems (e.g., liquid crystal systems). However, the order of these structures is often not easily controllable. This thesis aims to study 2D periodic Helfrich deformation structures by applying an electric field parallel to the helical axis of the cholesteric liquid crystal (CLC) planar texture and to control the large-area orderliness of the 2D microstructure by using the guidance of the 1D periodic microgroove structure prefabricated on the sample substrate.
Experimental results show that the 2D microgrid structure of Helfrich deformation is characterized by local (microscopic) order and large-area (macroscopic) disorder when an electric field is applied to the planar CLCs along the helical axis. If 1D periodic microgrooves are pre-established on the substrate of the sample and the period of the microgrooves matches the 2D microgrid spacing, then the 2D microgrid structure can be effectively controlled to form a large-area ordered arrangement. The large-area order of the 2D microgrid structure is directly related to the depth of 1D periodic microgrooves. When the period of 1D microgrooves does not match that of the 2D microgrid structure, the latter becomes prone to dislocation. This result improves the applicability of the well-known Helfrich deformation phenomenon. In the future, periodic micro–nano structures based on self-assembled supramolecular systems are expected to be further controlled or even customized, thereby contributing to the advancement of human science and technology applications.

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