The effects of sputtering conditions on the transport properties of YBa2Cu3Oy (YBCO) thin films were investigated in this work using an off-axis RF sputtering configuration. These conditions included the substrate temperature, the distance from the substrate to the target, the total pressure of the sputtering gas and the gas composition. The substrates were MgO (001) and SrTiO3 (001) and the sputtering gas was a mixture of Ar and O2. The YBCO films were characterized by resistivity measurements, X-ray diffraction and scanning force microscopy (SFM). Additionally, the optimum conditions of growing high-quality YBCO films were obtained. Those conditions were found to be: (1) the substrate is 3.5 cm horizontal and 3.0 cm vertical away from center of target, (2) the substrate temperature is 680°C for MgO and it is 720°C for SrTiO3, and (3) the pressure of the sputtering gas of Ar: O2 is (3 : 7) at 300 mTorr. The high-quality YBCO films revealed a transition temperature Tc(R = 0) at 87 ∼ 90 K, a normal-state resistance ratio R300K/R100K ∼ 3 and a normal-state resistivity at 300 K smaller than 200 μΩ cm.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering