PURPOSE: To prevent blackening of a transparent conductive film to improve the product yield, by sputtering insulating film materials while exposing the surface of the substrate, where the transparent conductive film is formed, to electron shower.

CONSTITUTION: A high frequency electric field is applied between a target 4 and a mesh anode electrode 8 connected to the earth, and molecules of insulating materials (such as SiO2 and ZnS) driven out by the collosion of Argon ions are stuck to the surface of a substrate 6. In this case, an anode electrode supporting the substrate 6 is kept in the same potential as the mesh anode electrode 8. Meanwhile, a bias voltage of -20W-100V is applied to an intermediate electrode 7. Electrons are radiated to the surface of the glass substrate from the mesh intermediate electrode 7 during the sputtering period by this application of the bias voltage, and the substrate becomes negative in respect to potential to stop the reducing action of a transparent conductive film stuck to the surface of the substrate, and thus, the occurrence of the blackening phenomenon is prevented.