Fabrication of low dimensional oxide thin films using cuprates as sacrificial layers

The characteristics and functionalities of complex oxide caught a lot of attention recently. For oxide perovskite thin film, an available modulation is to form heterostructure. Applying different perovskite allows strain manipulating and other effects that would change the characteristic which form a unique system. Unfortunately, not all kinds of complex oxide are acceptable to heterostructure. To give a wider range of combination for oxides, freestanding membrane was developed. La_0.7Sr_0.3MnO₃ and Sr₃Al₂O₆ are the two commonly used buffer layer. By etching the buffer layer, the thin film that deposit after the buffer layer ca n be separated from the substrate. In this work, we used YBa₂Cu₃O_7-x as a buffer layer, this method takes less time etching but maintain a fine freestanding membrane for later procedure. Furthermore, the process allows us to separate materials like La_0.7Sr_0.3MnO₃ with acid etchant because of the time etching YBa₂Cu₃O_7-x takes a few minutes while etching La_0.7Sr_0.3MnO₃ takes a few hours. Our goal is to develop a universal freestanding method that could applied to all kind of materials which could give access to more combination of complex oxide thin films.