在近年的材料研究上，雷射脈衝系統提供了各式各樣的材料結構藉以達成研究不同材料系統間的交互作用，其中又以獨立材料層(Freestanding)的研究最為新穎，透過犧牲層的手法，獲得無壓應力的獨立薄膜。此外，在材料的研究中，材料堆疊又是另外一門學問，而同質材料堆疊中，最出名的材料堆疊手法就是石墨烯的魔術角度，透過不同角度的堆疊達成電性調控的手法。
本研究中，我們透過結合了自支撐薄膜技術與轉移特定角度的材料堆疊手法，製作出不同晶向的薄膜堆疊，我們稱之為旋轉轉移(Twist transfer)。並透過磊晶在這特殊基板上的鐵酸鉍，進行結構與特性的分析，替氧化物研究上開啟一個新的研究方向。
從鐵酸鉍的保留行為上發現，在轉移區上的資訊保存上獲得更長的保留時間，這種旋轉轉移中的過渡帶上可高達五種不同極化方向的調控，藉以達到數種位元的記憶，替奈米元件中開啟一個新的儲存結構。

In the research of materials, different structures will lead to different boundary conditions and can be adopted to manipulate the characteristics of different material systems. Such features have made those materials exhibiting outstanding properties and potential candidates in applied physics. In this research, we demonstrate a new heterostructure called lateral epitaxy for complex oxide thin film by the combination of freestanding technique and the concept of twist stacking. With sacrificial layer, freestanding SrTiO3 thin film can be obtained and transferred with certain angle to fabricate twist substrate. In order to understand the influence of this structure, we have demonstrated epitaxial BiFeO3 on twist substrate and measured the functionalities by scanning probe microscopy (SPM), X-ray diffraction (XRD), transmission electron microscopy (TEM)…etc. It is worth to note that the domain structure of BiFeO3 exhibits significant difference in size, which is related to the angle between freestanding thin film and substrate. In the end, we provide a prototype application of twist BiFeO3 for lateral epitaxy.

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