Optimization of large-area YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7–δ </sub> thin films by pulsed laser deposition for planar microwave devices
Pei-Yu Xiong, Fucong Chen, Zhongpei Feng, Jingting Yang, Yudong Xia, Yuefeng Yuan, Xu Wang, Jie Yuan, Yun Wu, Jing Shi, Kui Jin
Abstract
This paper presents high quality YBa 2 Cu 3 O 7– δ (YBCO) thin films on LaAlO 3 substrate for microwave devices prepared by pulsed laser deposition (PLD). The double-sided YBCO films cover a large area and have been optimized for key parameters relevant to microwave device applications, such as surface morphology and surface resistance ( R s ). This was achieved by improving the target quality and increasing the oxygen pressure during deposition, respectively. To evaluate the suitability of the YBCO films for microwave devices, a pair of microwave filters based on microstrip fabricated on films from this work and a commercial company were compared. The results show that the YBCO films in this work could completely meet the requirements for microwave devices.