PURPOSE: To make a high-inductance superconductive coil formable easily, by forming a superconductor film on a surface of a plate-shaped substrate and next by forming a spiral groove on this superconductor film so deeply that the groove attains to said substrate.

CONSTITUTION: A ceramics superconductor film 2 is formed on a surface of a plate-shaped substrate 1 made of an insulating material by a sputtering method or the like. Next this substrate is rotated and concurrently a cutter 4 is used to cut the superconductor film 2 spirally to form a groove 3. Then said groove 3 should be so deep that it penetrates into the superconductor film 2 and attains to the substrate 1. When spacing of said groove 3 is made small, the number of coil turns can be enlarged, so that the coil with large inductance can be formed easily without joints.