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Phase Relations in the Ba-Y-Cu-O Films on SrTiO3 for the -Ex Situ BaF2- Process



Winnie K. Wong-Ng, Makoto Otani, Lawrence P. Cook, Mark D. Vaudin, James P. Cline, Ron Feenstra, T G. Holesinger


In situ x-ray diffraction was used to establish the phase relations in high-Tc superconductor Ba–Y– Cu–O films grown on SrTiO3 through the ex situ BaF2 process. These relations differ from bulk equilibrium phase assemblages in the BaO–Y2O3–CuOx system. In particular, BaY2CuO5 the “green phase”, a common impurity phase in bulk processing, is absent in the films. Because of the absence of this green phase, the compositional stability field of Ba2YCu3O6+x expands considerably as compared to that of the bulk system, resulting in the tie lines Ba2YCu3O6+x–Y2O3 and Ba2YCu3O6+x–Y2Cu2O5.
Applied Physics Letters


Wong-Ng, W. , Otani, M. , Cook, L. , Vaudin, M. , Cline, J. , Feenstra, R. and Holesinger, T. (2007), Phase Relations in the Ba-Y-Cu-O Films on SrTiO3 for the -Ex Situ BaF2- Process, Applied Physics Letters, [online], (Accessed May 27, 2024)


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Created March 5, 2007, Updated February 2, 2018