Superconducting device and method of manufacturing the same

A method of manufacturing a superconducting device, comprising:

• subjecting a first superconductor layer, which is supported by a substrate and containing superconductor of oxide, to an etching treatment;
• subjecting the first superconductor layer to a heat treatment after the etching treatment;
• and
• forming a second superconductor layer on the first superconductor layer after the heat treatment, the second superconductor layer comprising a material represented by a formula of (Yb1-yLn′y)AE′2M′3Oz in which Ln′ represents at least one metal selected from the group comprising Y and lanthanoids, AE′ represents at least one of alkaline earth metals, M′ represents a metal which contains 80 atomic % or more of Cu, y represents a value within a range of 0 to 0.9, and z represents a value within a range of 6.0 to 8.0,
• wherein the heat treatment is an annealing treatment, the heat treatment is performed on the first superconductor layer whose surface is uncovered, a temperature of the substrate on the formation of the second superconductor layer is lower than a temperature of the substrate on the heat treatment, and the second superconductor layer is in contact with an etched surface of the first superconductor layer.