Method of producing wired circuit board

Abstract

A method of producing a wired circuit board that can prevent the electrostatic damage of the components mounted on the wired circuit board effectively, while preventing operation errors of the device caused by the static electricity. After a thin metal film is formed over an entire area of a front side of an insulating cover layer and an entire surface of a conductor layer at a terminal portion thereof by sputtering, a metal oxide layer is formed on the thin metal layer by an oxidation-by-heating method or by the sputtering. According to this method, since the semi-conductor layer comprising the thin metal film and the metal oxide layer is formed on the surface of the insulating cover layer, the electrostatic damage of the components mounted on the wired circuit board can be prevented effectively. Also, the operation errors of the device caused by the construction wherein only the thin metal film is formed can also be prevented effectively. Further, the semi-conductor layer having a uniform surface resistance which falls within a preferable range can be formed, as compared with the construction wherein the metal oxide layer is formed directly on the insulating cover layer by the reactive sputtering or by the sputtering using the metallic oxide target.