Preparation of YBCO Superconducting Thin Films on (001) MgO Substrate by DC Magnetron Sputtering

• Main Authors: Wen-Ruey Chang, 張文瑞
• Other Authors: George C. Tu
• Format: Others
• Language: en_US
• Published: 1993
• Online Access: http://ndltd.ncl.edu.tw/handle/72475528360425476764

碩士 === 國立交通大學 === 材料科學(工程)研究所 === 81 === The present work reports a study of the effects of the deposition conditions on the microstructure and superconductive properties of YBCO thin films formed by DC magnetron sputtering plasma, and the critical temperatures were determined by four- probe method. The films were c-axis preferentially oriented with respect to (001) MgO surface at substrate temperatures 680-700 C. The resputtering effect of oxygen can be greatly reduced with a high argon-oxygen ratios and a high gas pressures. Although X-ray diffraction shows a definite c-axis alignment normal to the substrate plane, futher analysis reveals that a-axis alignment normal to the substrate plane, and numerous second phases are also observed. The second phases including CuO and Y2O3 are identified by energy dispersive X- ray spectrometer and the detailed microstructure are analyzed by transmission electron microscopy. In our work, YBCO thin films on MgO substrate attain a Tc (R=0) of 83 K and Jc of 10 5 A/cm2 at 60 K.