MgO thin films with different textures are fabricated by the ion beam assisted （IBAD） method on the Y2O3/Al2O3 buffered C276 tape. Then a CaO2 layer is directly grown on the IBAD-MgO film by the pulsed laser deposit...MgO thin films with different textures are fabricated by the ion beam assisted （IBAD） method on the Y2O3/Al2O3 buffered C276 tape. Then a CaO2 layer is directly grown on the IBAD-MgO film by the pulsed laser deposition （PLD） method. Effects of lBAD-MgO texture, substrata temperature and thickness on the grain alignment of the CeO2 layer are investigated. Film characterization is performed by x-ray diffraction and atomic force microscopy. It is found that the orientation and texture degree of the CaO2 layer are very sensitive to the IBAD-MgO texture. By optimizing the IBAD-MgO texture, CeO2 has pure （002） orientation and excellent biaxial texture deposited in a broad substrata temperature range. In addition, the PLD-CeO2 layer has a thickness effect. Under the optimized experimental condition, the PLD-CeO2 layer has a high in-plane texture of △φ = 2.9° and a smooth surface with an rms surface roughness of less than 2nm. The critical current density Jc of a 0.4μm-thick YBCO film deposited on the CeO2 layer is 6.25 × 106 A/cm2 at 77K and a self-field.展开更多
CeO2/YSZ/CeO2 buffer layers were prepared on biaxial textured Ni-5at.%W substrate by direct-current magnetron reactive sputtering with the optimum process. YBCO thin films were deposited on CeO2/YSZ/CeO2 buffered Ni-5...CeO2/YSZ/CeO2 buffer layers were prepared on biaxial textured Ni-5at.%W substrate by direct-current magnetron reactive sputtering with the optimum process. YBCO thin films were deposited on CeO2/YSZ/CeO2 buffered Ni-5at.%W substrate at temperature ranging from 500℃ to 700℃ by diode de sputtering. By optimizing substrate temperature, pure c-axis oriented YBCO films were obtained. The mierostruetures of CeO2/YSZ/CeO2 buffer layers were characterized by X-ray diffraction. A smooth, dense and crack-free surface morphology was observed with scanning electron microscopy. The critical current density Jc about 0.75 MA/cm2 at 77 K was obtained.展开更多
A full solution method has been developed as a low cost process of YBa2Cu3OT-x （YBCO） coated conductor fabrication. In this study, highly biaxially textured SrTiO3 （STO） buffer layers were fabricated on LaAlO3 （...A full solution method has been developed as a low cost process of YBa2Cu3OT-x （YBCO） coated conductor fabrication. In this study, highly biaxially textured SrTiO3 （STO） buffer layers were fabricated on LaAlO3 （LAO） single crystal substrates by sol-gel method using metal alkoxides as the staring precursor materials. High quality YBCO superconducting film was then fabricated on STO-buffered LAO substrate by trifluoroacetic metalorganic deposition （TFA-MOD） method. For the YBCO superconducting film, only （001） diffraction peaks can be detected by XRD （X-ray diffraction） analysis with no other phases detectable. Especially, Inplane texture of YBCO film is improved compared to that of STO buffer layer from phi scans analysis, which indicates the self-epitaxy phenomenon explained by considering interracial energy. STO and YBCO films both show c-axis oriented grains growth and have uniform surface microstructure. A critical transition temperature, TC （R=0） of 89.5 K and a critical current density of 2 mA/cm2 （77 K, self-field） were obtained for a 0.2μm thick YBCO film on STO-buffered LAO substrate. No reaction between YBCO and STO was detected by XRD analysis. This full solution process may provide a promising low cost fabrication route for YBCO coated conductors on metal tape.展开更多
基金Supported by the ITER Project of the Ministry of Science and Technology of China under Grant No 2011GB113004the Shanghai Commission of Science and Technology under Grant Nos 09DZ1206000 and 11DZ1100402the Youth Fund of Natural Science Foundation of China under Grant No 11204174
文摘MgO thin films with different textures are fabricated by the ion beam assisted （IBAD） method on the Y2O3/Al2O3 buffered C276 tape. Then a CaO2 layer is directly grown on the IBAD-MgO film by the pulsed laser deposition （PLD） method. Effects of lBAD-MgO texture, substrata temperature and thickness on the grain alignment of the CeO2 layer are investigated. Film characterization is performed by x-ray diffraction and atomic force microscopy. It is found that the orientation and texture degree of the CaO2 layer are very sensitive to the IBAD-MgO texture. By optimizing the IBAD-MgO texture, CeO2 has pure （002） orientation and excellent biaxial texture deposited in a broad substrata temperature range. In addition, the PLD-CeO2 layer has a thickness effect. Under the optimized experimental condition, the PLD-CeO2 layer has a high in-plane texture of △φ = 2.9° and a smooth surface with an rms surface roughness of less than 2nm. The critical current density Jc of a 0.4μm-thick YBCO film deposited on the CeO2 layer is 6.25 × 106 A/cm2 at 77K and a self-field.
文摘CeO2/YSZ/CeO2 buffer layers were prepared on biaxial textured Ni-5at.%W substrate by direct-current magnetron reactive sputtering with the optimum process. YBCO thin films were deposited on CeO2/YSZ/CeO2 buffered Ni-5at.%W substrate at temperature ranging from 500℃ to 700℃ by diode de sputtering. By optimizing substrate temperature, pure c-axis oriented YBCO films were obtained. The mierostruetures of CeO2/YSZ/CeO2 buffer layers were characterized by X-ray diffraction. A smooth, dense and crack-free surface morphology was observed with scanning electron microscopy. The critical current density Jc about 0.75 MA/cm2 at 77 K was obtained.
基金supported by the National Natural Science Foundation of China under contract No.50606027the National High Technology Research and Development Program ("863 program") under contract No.2002AA306211the International Collaboration Project under contract No.2004AA32H020.
文摘A full solution method has been developed as a low cost process of YBa2Cu3OT-x （YBCO） coated conductor fabrication. In this study, highly biaxially textured SrTiO3 （STO） buffer layers were fabricated on LaAlO3 （LAO） single crystal substrates by sol-gel method using metal alkoxides as the staring precursor materials. High quality YBCO superconducting film was then fabricated on STO-buffered LAO substrate by trifluoroacetic metalorganic deposition （TFA-MOD） method. For the YBCO superconducting film, only （001） diffraction peaks can be detected by XRD （X-ray diffraction） analysis with no other phases detectable. Especially, Inplane texture of YBCO film is improved compared to that of STO buffer layer from phi scans analysis, which indicates the self-epitaxy phenomenon explained by considering interracial energy. STO and YBCO films both show c-axis oriented grains growth and have uniform surface microstructure. A critical transition temperature, TC （R=0） of 89.5 K and a critical current density of 2 mA/cm2 （77 K, self-field） were obtained for a 0.2μm thick YBCO film on STO-buffered LAO substrate. No reaction between YBCO and STO was detected by XRD analysis. This full solution process may provide a promising low cost fabrication route for YBCO coated conductors on metal tape.
