藉由成長鈣鈦礦氧化物薄膜長，能產生許多功能性材料。經由將單晶薄膜從基板上分離，轉移至任意基板上，能夠創造出具有新功能的異質界面。由於這種利用犧牲層的蝕刻來轉移單晶薄膜的技術，能夠在轉移後保持原來的單晶性質，並且不會有結構上的損壞，甚至能使功能性氧化物的特性，有所提升。在本實驗中，我們利用YBCO當作犧牲層，藉由HCl溶液分解後，將鈣鈦礦薄膜與基板分離，成功的轉移至Si基板上。利用AFM、同步輻射的XRD以及電性的量測，來檢測freestanding前後薄膜的特性。結果表明磊晶鈣鈦礦薄膜在經過基板應力的釋放後都顯示出鐵磁-順磁轉換溫度Tc的上升，並且晶格結構與單晶非常相近，並且整個蝕刻的時間只需要5~10分鐘，比目前已知的分離單晶薄膜的製程還要快上許多。顯示出YBCO作為freestanding製程的一種良好媒介，具有快速、高品質、廣泛的分離單晶鈣鈦礦薄膜的優點。

Single crystal thin films of perovskite oxides show a vast variety of functional properties. By separating the single crystal thin films from the substrate and transferring it to an arbitrary substrate, heterointerfaces which have new function properties can be created. We reported a method by YBCO sacrificial layer dissolved in HCl solution separates the single crystal thin film. Atomic force microscopy is used to scan the surface of the thin film. The lattice constant of each axis and the stress from the substrate are calculated by high resolution XRD. Resistivity is measured by using standard four point probe method. Results indicate that there is a enhancement in the ferromagnetic metal-paramagnetic insulator transition temperature of freestanding LSMO thin films compared to that of as grown LSMO . We also demonstrated that by using YBCO as a medium for freestanding process can separate epitaxial thin films from substrates rapidly and can gain the films with high quality in structure and complete shape.

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