Manufacture of thin superconductor

PURPOSE: To obtain a high-transition-temperature superconducting tape etc., by forming an intermediate body and forming a thin body through contracting the cross section of the intermediate body. CONSTITUTION: An intermediate body, composed of a cladding material surrounding a few oxide powder, is formed, and a thin body is formed of the intermediate body by a cross section contracting means to be heat treated. By this heat treating, the oxide powder can be sufficiently sintered; and after the completion of this heat treatment, the superconductivity of the oxide powder, wherein the chemical composition of the sintered oxide is sintered, or of an unclad sintered oxide made of the oxide power can be obtained. A tape 30 obtained in this method is equipped with a sintered oxide superconductor 31, a diffusion barrier layer 33, and a metallic jacket 32.