A superconductor comprising: a substrate having a tape shape that extends in a first direction and having surfaces which are defined as a top surface, a bottom surface, and both side surfaces; a superconducting layer disposed on the top surface of the substrate; a first stabilizing layer disposed on the superconducting layer and containing a first metal; a protective layer disposed on the first stabilizing layer and containing a second metal which is different from the first metal; a first alloy layer disposed between the first stabilizing layer and the protective layer, and containing the first and second metals, wherein the protective layer is in contact with opposing side surfaces of each of the substrate, the superconducting layer, the first stabilizing layer and the first alloy layer, and the bottom surface of the substrate, wherein the protective layer surrounds the substrate, the superconducting layer, the first stabilizing layer and the first alloy layer; a second stabilizing layer disposed only on a top surface, only a bottom surface, or only a top and a bottom surface of the protective layer; a low melting point metal layer disposed between the protective layer and the second stabilizing layer, the low melting point metal layer containing a third metal which is different from the first metal and the second metal, and a second alloy layer disposed between the protective layer and the low melting point metal layer, the second alloy layer having a surface area larger than a surface area of the first alloy layer and containing the second metal and the third metal, wherein the low melting point metal layer is disposed on a top surface, a bottom surface, and both side walls of the protective layer. a substrate having a tape shape that extends in a first direction and having surfaces which are defined as a top surface, a bottom surface, and both side surfaces; a superconducting layer disposed on the top surface of the substrate; a first stabilizing layer disposed on the superconducting layer and containing a first metal; a protective layer disposed on the first stabilizing layer and containing a second metal which is different from the first metal; a first alloy layer disposed between the first stabilizing layer and the protective layer, and containing the first and second metals, wherein the protective layer is in contact with opposing side surfaces of each of the substrate, the superconducting layer, the first stabilizing layer and the first alloy layer, and the bottom surface of the substrate, wherein the protective layer surrounds the substrate, the superconducting layer, the first stabilizing layer and the first alloy layer; a second stabilizing layer disposed only on a top surface, only a bottom surface, or only a top and a bottom surface of the protective layer; a low melting point metal layer disposed between the protective layer and the second stabilizing layer, the low melting point metal layer containing a third metal which is different from the first metal and the second metal, and a second alloy layer disposed between the protective layer and the low melting point metal layer, the second alloy layer having a surface area larger than a surface area of the first alloy layer and containing the second metal and the third metal, wherein the low melting point metal layer is disposed on a top surface, a bottom surface, and both side walls of the protective layer.