Processing conditions of heavily Pb doped superconducting (Bi, Pb)(2)Sr2Ca2Cu3Oy thin films


Guldeste A. , Goringe M. J.

JOURNAL OF CRYSTAL GROWTH, cilt.257, ss.129-135, 2003 (SCI İndekslerine Giren Dergi) identifier

  • Cilt numarası: 257
  • Basım Tarihi: 2003
  • Doi Numarası: 10.1016/s0022-0248(03)013181-2
  • Dergi Adı: JOURNAL OF CRYSTAL GROWTH
  • Sayfa Sayıları: ss.129-135

Özet

Bi(Pb)SrCaCuO thin films containing a high ratio of Pb (0.9 < Pb/Bi < 1.5), about 0.5 mum thick, deposited on MgO (001) by RF-magnetron sputtering have been assessed as a function of their initial atomic concentration. It was found that Bi-content of 1.4 < Bi < 1.8 (normalised to Cu:3) in as-deposited film may provide almost single phase Bi-2223 thin films with T-c values running from 105.5 to 109.5 K (for the Bi ratio of close to 1.8 Tc is 106 K), and J(c) > 10(4) A/cm(2) at 77 K. It was also found that the Bi-content should be below 1.9 or lower than the Sr-content to prevent peeling off of the film during the high temperature annealing process, while Sr/Ca ratio remains around 1 in this heavily Pb doped initial film composition. Although the Pb/Bi ratio is not critical in the range studied when it is above 1.3, slow heating and cooling rate (1degreesC/min) is necessary to prevent the retention of excess Ca2PbO4 causing poor microstructure in the film. (C) 2003 Elsevier B.V. All rights reserved.