PURPOSE: To produce a device having thin film of an oxide superconducting material of required pattern, by supplying component element of the oxide superconductive material in the form of thin film and alkaline earth metal in the form of fluoride onto substrate, and subjecting the film to a heat treatment in the presence of water and oxygen.

CONSTITUTION: The SrTiO3 substrate 11 is coated with the tin film 12 of Y2O3, CuO, BaF2, to about 500nm thickness by laser abrasion. The surface of the thin film 12 is then provided with a metallic thin film 13 by sputtering, etc., and further, a thin film 14 of a UV sensitive photoresist is deposited by spinning. The photoresist thin film 14 is formed with opening 15 by an aq. NaOH soln. after exposing and developing and, further, the exposed parts of the gold thin film 13 is etched by an aq. KI/I2 soln. and, thereafter, the residual photoresist thin film 14 is removed. Next, the substrate is heated for about one hour at about 850°C in wet oxygen and an oxide superconductive material 16 (YBa2Cu3 O6.7) is formed in the parts not coated with the thin film 12. The residual gold thin film 13 is removed at need, to form the pattern having fine detail.