複雜性氧化物因為其豐富的物理特性和可調性，近年來吸引了不少科學界的注意。由鈣鈦礦薄膜(perovskite thin film)堆疊而成的異質結構(heterostructure)便成了這方面研究的平台，透過不同的基板和多種鈣鈦礦薄膜的沉積使得這類複雜性氧化物具備可調性。然而，不論是何種薄膜成長方式，幾乎都不可避免地會遇到薄膜和基板之間的晶格不匹配(lattice mismatch)和熱膨脹不匹配(thermal expansion mismatch)，進而導致不同程度的應力(stress)被施加到薄膜上。
由於鈣鈦礦的許多物理特性取決於其晶格的結構和扭曲(distortion)，導致鈣鈦礦薄膜的物理特性對於應變會有很顯著的影響。釕酸鍶(Strontium ruthenate, SrRuO3)作為複雜性氧化物的成員，其在不同鈣鈦礦基板上可以容易的磊晶成長並且有良好的導電性，時常作為氧化物異質結構中的導電層。在過去的實驗中，為了討論不同應力下的SrRuO3薄膜，會使用不同的鈣鈦礦作為SrRuO3磊晶的基板。而有一組團隊發展了自支撐獨立(Freestanding)的SrRuO3薄膜以探討不受成長基板應力影響的物理特性。我們的研究在於使用鑭鍶錳氧(La0.7Sr0.3MnO, LSMO)作為犧牲層的自支撐獨立薄膜製程，應用到SrRuO3薄膜上。使我們用更短的時間，更安全的工法得到僅數個原子層的自支撐獨立SrRuO3薄膜。

Strain plays a crucial role when it comes to perovskite thin film. Physical properties were formed because of the symmetric structure. The relation between the center atom and the corner atom is the key to how the film exhibit. Majority of the strain comes from the lattice mismatch between the film and the substrate. SrRuO3 is a ferromagnetic material with TC∼150K, and it could vary as the strain changes. The research on strain effect was done by combining different substrate which leads to different mismatch in lattice constant, in order to generate different degrees of strain. However, this method couldn’t fully release the strain. In this case, we applied a procedure to manufacture freestanding SrRuO3 thin film. By introducing a La0.7Sr0.3MnO3 as a sacrificial layer between the SrRuO3 film and the SrTiO3 substrate. We were able to create a freestanding film by etching the La0.7Sr0.3MnO3 layer. Which gives access to the characteristics of freestanding SrRuO3 thin film.

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