PURPOSE: To produce a rotating cathode target with which a film can be fast formed to high density with high freedom degree by forming an undercoat on a cylindrical target holder and then applying a ZnO powder containing a specified amt. of phosphides of In, Zn, Sn, Ga by plasma thermal spraying.

CONSTITUTION: An undercoating layer is formed on a copper or stainless steel cylindrical target holder 2, preferably after the surface is roughened by sand blasting or the like. This undercoating layer is formed to have a medium coefft. of thermal expansion between the coeffts. of thermal expansion of the target holder 2 and a target layer to be formed, and/or to have coefft. of thermal expansion near that of the target layer. Then, a powder essentially comprising ZnO and containing 0.01-30wt.% phosphides of at least one metal selected from In, Zn, Sn, Ga is sent in a half-molten state onto the undercoating layer by high temp. plasma gas to form the target layer. By using the obtd. rotating cathode target for sputtering, an oxide transparent thin film having low refractive index is stably formed.