| 摘要 |
PURPOSE:To readily obtain a thin film, tapelike unit or wiry material, etc., of a Bi oxide-based superconductor having the high critical temperature with excellent reproducibility and high efficiency by heat-treating a Bi-based oxide superconductor in the presence of a lead-containing compound oxide. CONSTITUTION:A Bi-based oxide superconductor is heat-treated in the presence of a lead (Pb)-containing compound oxide. Although the lead-containing compound oxide is not especially limited, e.g. Sr2PbO4, Ca2PbO4, Cu6PbO8 and Bi12PbO20, are cited. The activity of PbO is reduced by using the lead-containing compound oxide in an annealing process to increase the Tc in the above- mentioned method. Furthermore, the vapor pressure of the PbO can be regulated to optional values by using a gradient furnace having a temperature gradient as a heat-treating furnace in the aforementioned method. Thereby, an adequate amount of the Pb can be added to a thin film, tapelike unit, wiry material, etc., of the Bi-based oxide superconductor. |
