| 摘要 |
PURPOSE:To unnecessitate the complicated device for temperature control of a first superconductive layer by a method wherein the oxidation treatment to be performed in the process, wherein a tunnel barrier layer is formed, contains a first thermal oxidation treatment, a second thermal oxidation treatment and a high-frequency plasma oxidation treatment are performed in succession, thereby enabling to obtain the ratio RS/RN which is approximately in the same degree as the conventional one or above it. CONSTITUTION:A first superconductive layer 2, consisting of a lead-indium-gold alloy, is formed on an insulated substrate 1 by performing the process including a vapor-deposition treatment. Said insulated substrate 1 is supported on a heating plate 23 which is arranged in a vapor-deposition chamber 21, the vapor-deposition chamber 21 is brought under high vacuum condition and also in the condition wherein the heating plate 23 is not heated and the insulated substrate 1 is maintained at the normal temperature, a layer consisting of gold, a layer consisting of lead and a layer consisting of indium are successively laminated on the insulated substrate 1, and the first superconductive layer 2 is formed by heating up said insulated substrate 1 for 30min using a heating device 22 located outside the vapor-deposition chamber 21. Then a tunnel barrier layer 4, consisting of a lead alloy, is formed on the surface of the first superconductive layer 2 by performing a process including an oxidation treatment. |
