To obtain a surface which is stable to thermal treatment and free from deposition particles, by dipping the surface in hydrogen chloride methanol liquid and performing chemical treatment.
A surface of oxide superconductor which is shown by a composition chemical formula M'Ba2Cu3O7-δ (in the formula, M' is Y, and rare earth element such as Nd, Sm and Eu or these alloy, and δ shows oxygen deficiency amount) is worked by polishing and dipped in hydrogen chloride methanol liquid whose concentration is 0.01% for 10 seconds. As a result, a deteriorated layer is eliminated, and the surface is stabilized, thereby preventing generation of particles or the like on the surface. The course of subsequent thermal treatment for obtaining superconductivity and film forming treatment. Hence, material having excellent superconductivity and crystallinity can be obtained.
ZAMA HIDEAKI
MORISHITA TADATAKA
