Large area YBCO superconductive films prepared by d.c. magnetron sputtering have reached: T c>89 K, J c>3.5×10 6 A/cm 2 (77 K, 0 T), R s=0.25 mΩ, at 77.5 K, 9894 MHz. The microstructure an...Large area YBCO superconductive films prepared by d.c. magnetron sputtering have reached: T c>89 K, J c>3.5×10 6 A/cm 2 (77 K, 0 T), R s=0.25 mΩ, at 77.5 K, 9894 MHz. The microstructure analysis of the film showed it has fine monocrystalline structure and the crystalline perfectness is satisfactory. The oscillator, filter and antenna made from these films are good in performance. Therefore, YBCO superconductive films have great prospect in application.展开更多
High quality epitaxial YBa2Cu3O7-δ (YBCO) superconducting films were fabricated on (00l) LaAlO3 substrates using the direct-current sputtering method. The attainment of an unusually high film thickness (up to 2...High quality epitaxial YBa2Cu3O7-δ (YBCO) superconducting films were fabricated on (00l) LaAlO3 substrates using the direct-current sputtering method. The attainment of an unusually high film thickness (up to 2.0 μm) without mi-crocracking was attributed in part to the presence of pores correlated with yttrium-rich composition in the films. The influ-ence of the film thickness on the microstructure was investigated by X-ray diffraction conventional scan (θ-2θ,ω-scan,pole figure) and high-resolution reciprocal space mapping. The films were c-axis oriented with no a-axis-oriented grains up to the thickness of 2 μm. The surface morphology and the critical current density (Jc) strongly depended on the film thickness. Furthermore,the reasons for these thickness dependences were elucidated in detail.展开更多
文摘Large area YBCO superconductive films prepared by d.c. magnetron sputtering have reached: T c>89 K, J c>3.5×10 6 A/cm 2 (77 K, 0 T), R s=0.25 mΩ, at 77.5 K, 9894 MHz. The microstructure analysis of the film showed it has fine monocrystalline structure and the crystalline perfectness is satisfactory. The oscillator, filter and antenna made from these films are good in performance. Therefore, YBCO superconductive films have great prospect in application.
文摘High quality epitaxial YBa2Cu3O7-δ (YBCO) superconducting films were fabricated on (00l) LaAlO3 substrates using the direct-current sputtering method. The attainment of an unusually high film thickness (up to 2.0 μm) without mi-crocracking was attributed in part to the presence of pores correlated with yttrium-rich composition in the films. The influ-ence of the film thickness on the microstructure was investigated by X-ray diffraction conventional scan (θ-2θ,ω-scan,pole figure) and high-resolution reciprocal space mapping. The films were c-axis oriented with no a-axis-oriented grains up to the thickness of 2 μm. The surface morphology and the critical current density (Jc) strongly depended on the film thickness. Furthermore,the reasons for these thickness dependences were elucidated in detail.