PURPOSE: To perform deburring so as to improve the quality and yield of precision components by showering such ions as Ar, Kr, Xe, etc. on V shaped minute grooves engraved by cutting closely with each other on a disk made of copper, aluminum, or plastics.

CONSTITUTION: A diamond tool 3 is fed to the main surface 1a of a disk 1 to a minute depth of cut, and when the disk is rotated specified times, the tool is fed in the radial direction of the disk. By repeating such a step, a lot of minute grooves 5 of concentricity are formed on the main surface 1a. The ends of walls of these V shaped grooves become sharp with tips forming burrs 8. Then, the disk 1 is put into an ion shower room 9. And when the main surface 1a of the disk 1 is exposed to ion shower 10, a desired machined surface without burrs 8 can be obtained as a result of deburring by ion spattering. The quality and yield of precision components can, therefore, be improved by applying such a minute groove forming method.