无氟高分子辅助金属有机物沉积法制备SmBCO超导薄膜
摘要
本论文综述了超导材料的发展、应用以及分类；简要介绍了REBCO高温超导薄膜的发展和制备方法;重点介绍了REBCO高温超导薄膜的结构、性能参数;并阐明了本课题的研究目的及内容。
本论文采用无氟高分子辅助金属有机物沉积方法(PA-MOD)在LaA103单晶片上制备SmBa2Cu307.x(SmBCO)薄膜。首先全面介绍了制备SmBCO薄膜的整个工艺流程；其次对无氟PA-MOD法制备SmBCO薄膜的热处理工艺进行研究,通过实验确定最佳外延生长温区为790℃,然后引入部分熔融进一步优化SmBCO的外延生长工艺；对样品进行X射线衍射(XRD)分析、扫描电镜(SEM)分析以及综合物性测量系统PPMS的测试,得到的SmBCO薄膜c轴织构良好,表面平整致密；综合物性测量系统(PPMS)测试结果表明SmBCO样品的超导临界温度T。为91K左右。
本文接着选取Co元素微量掺杂SmBCO薄膜(名义掺杂量分别为0.001,0.002和0.003),研究了Cu位掺杂对SmBCO薄膜超导性能的影响。采用优化后的热处理工艺制备了微量Co掺杂的SmBCO薄膜,并利用XRD、SEM、PPMS等表征手段对薄膜性能进行分析测试。结果表明,微量Co掺杂后的SmBCO薄膜的表面形貌平整致密。
最后,采用多次旋涂制备SmBCO双层膜,研究SmBCO双层膜的织构和微结构,双层膜的厚度为243nm左右。
In this thesis, the development, application and classification of superconducting materials were summarized.The development and fabrication methods of REBCO high temperature superconducting films were introduced.The structure, performance parameters were presented with the research goal and content.
SmBa2Cu3O7-x(SmBCO)films have been synthesized on single crystal substrates of LaA103by using a fluorite-free PA-MOD method. First the whole treating process of SmBCO film fabrication has been introduced.The anneal process of using a fluorite-free PA-MOD method to synthesize SmBCO thin film was investigated. The optimal epitaxial growth temperature was790℃, and melt-partially mehod was proposed to optimize SmBCO film process. The SmBCO thin films have been investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM) and PPMS method. The results showed that exhibited high c-axis orientation, smooth, dense and crack-free surface. The PPMS test results show that the SmBCO samples of the superconducting critical temperature T c of about91K.
The effect of slight Co element doping at Cu site (nominal doped level was0.001,0.002and0.003) doping on critical current densities of SmBCO films in high magnetic field was also investigated. SmBCO films with slight Co element doping have been synthesized by using the optimized fluorite-free MOD method. The SmBCO thin films have been investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM) and PPMS method. Research results show that SmBCO films with slight Co element doping displays smooth and dense surface morphology.
In the last part of the thesis, a number of spin-coating preparation of SmBCO double-thick film, research of SmBCO double-layer thick film texture and microstructure, the bilayer membrane thickness of243nm.
本论文采用无氟高分子辅助金属有机物沉积方法(PA-MOD)在LaA103单晶片上制备SmBa2Cu307.x(SmBCO)薄膜。首先全面介绍了制备SmBCO薄膜的整个工艺流程；其次对无氟PA-MOD法制备SmBCO薄膜的热处理工艺进行研究,通过实验确定最佳外延生长温区为790℃,然后引入部分熔融进一步优化SmBCO的外延生长工艺；对样品进行X射线衍射(XRD)分析、扫描电镜(SEM)分析以及综合物性测量系统PPMS的测试,得到的SmBCO薄膜c轴织构良好,表面平整致密；综合物性测量系统(PPMS)测试结果表明SmBCO样品的超导临界温度T。为91K左右。
本文接着选取Co元素微量掺杂SmBCO薄膜(名义掺杂量分别为0.001,0.002和0.003),研究了Cu位掺杂对SmBCO薄膜超导性能的影响。采用优化后的热处理工艺制备了微量Co掺杂的SmBCO薄膜,并利用XRD、SEM、PPMS等表征手段对薄膜性能进行分析测试。结果表明,微量Co掺杂后的SmBCO薄膜的表面形貌平整致密。
最后,采用多次旋涂制备SmBCO双层膜,研究SmBCO双层膜的织构和微结构,双层膜的厚度为243nm左右。
In this thesis, the development, application and classification of superconducting materials were summarized.The development and fabrication methods of REBCO high temperature superconducting films were introduced.The structure, performance parameters were presented with the research goal and content.
SmBa2Cu3O7-x(SmBCO)films have been synthesized on single crystal substrates of LaA103by using a fluorite-free PA-MOD method. First the whole treating process of SmBCO film fabrication has been introduced.The anneal process of using a fluorite-free PA-MOD method to synthesize SmBCO thin film was investigated. The optimal epitaxial growth temperature was790℃, and melt-partially mehod was proposed to optimize SmBCO film process. The SmBCO thin films have been investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM) and PPMS method. The results showed that exhibited high c-axis orientation, smooth, dense and crack-free surface. The PPMS test results show that the SmBCO samples of the superconducting critical temperature T c of about91K.
The effect of slight Co element doping at Cu site (nominal doped level was0.001,0.002and0.003) doping on critical current densities of SmBCO films in high magnetic field was also investigated. SmBCO films with slight Co element doping have been synthesized by using the optimized fluorite-free MOD method. The SmBCO thin films have been investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM) and PPMS method. Research results show that SmBCO films with slight Co element doping displays smooth and dense surface morphology.
In the last part of the thesis, a number of spin-coating preparation of SmBCO double-thick film, research of SmBCO double-layer thick film texture and microstructure, the bilayer membrane thickness of243nm.
引文
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[10]木丽云.无氟MOD法制备GdBCO高温超导薄膜研究.西南交通大学硕士学位论文.2008.
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[22]H Muller-Bushchbaum, M. W. Wollschlager. Uber ternare Oxocuprate. VII. Zur Kristallstruktur von Nd2Cu04. Chem.1975,414:76.
[23]T. Muromachi, F. Izumi, Y. Uchida,et al. Oxygen deficiency in the electron-doped superconductor Nd2-xCexCuO4-y. Physica. C.1989,159:634.
[24]周华明.无氟MOD法制备DBCO外延薄膜及工艺研究.西南交通大学硕士学位论文.2007.
[25]I. Iwonkim, Epitaxial Growth and Stabilization of Transition Metal Nitride based Superlattices and Buffer Layers.Northwest University. Doctor of Philosopy,2000.
[26]赵艳娥.高温超导YBa2Cu3O7-δ涂层的低成本制备及弱连接改善研究.西南交通大学硕士学位论文.2004
[27]Y. Shiohara, A. Endo. Crystal growth of bulk high-Tc superconducting oxide materials. Materials Science and Engineering R:1997
[28]T. Pertrisor, V. Boffa, L. Cionteab,et al. High-quality surface YBCO thin films prepared by off-axis pulsed laser deposition technique. Physica C.1997,487.
[29]Y. Kumagai,Y Yoshida, M. Iwata.et al. Fabrication and characterization of Nd1+xBa2-xCu3O7-y thin films deposited by metal-organic chemical vapor deposition using liquid state sources. Physica C.1998,35.
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[33]P. Catania, N. Hovnanian, L. Cot,et al. Influence of sol-gel methods on the superconducting YBa2Cu307-x phase. Mat. Res. Bull.1990,631.
[34]M. W. Rupich, Y. P. Liu, Ibechem,et al. Low-temperature formation of YBa2Cu3O7-x superconducting films from molecular Cu-Ba-Y precursors. Appl. Phy. Lett.60,1992, 1384.
[35]A. ShethH, V. Lasrado. Review and evaluation of methods for application of epitaxial buffer and superconductor layers. Applied Superconductivity.1998,6:855
[36]姜守振.脉冲激光沉积制备碳纳米材料进展.山东师范大学学报自然科学版.2011年26卷3期.
[37]车全德.钙锶铋钛铁电薄膜晶粒定向工艺及机理的研究.山东建筑大学硕士学位论文.2010.
[38]T. Iguchi, T. Araki, Y Yamada.et al. Metal-organic deposition of RE-Ba-Cu-O (RE=Dy, Ho, Er, and Tm) films using trifluoroacetates. Physica. C.2003,900:392.
[39]田莳.材料物理性能.北京航空航天大学出版社.2000
[40]孙瑞萍.高分子辅助化学溶液沉积法制备REBiO3新型缓冲层.西南交通大学硕士论文.2008.
[41]周玉,武高辉.材料分析测试技术.哈尔滨工业大学出版社.1997.
[42]牛鹏霞.芳纶编织绳的涂层处理与性能研究.天津工业大学硕士学位论文.2011
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