PURPOSE: To control the quality of a film and to efficiently form the film at a high vapor deposition rate by cluster ion beam vapor deposition by using a gaseous oxygen introducing device to excite, dissociate and ionize gaseous oxygen in the vicinity of a substrate.

CONSTITUTION: The gaseous oxygen introducing device consisting of a reactive gas introducing device 4, a gas ion generator 9 and a power unit 10 for the gas ion generator is used. A region, in which the gaseous oxygen is excited, dissociated and ionized (activated state), is formed in the vicinity of the substrate 7, especially of its vapor deposition surface. The vapor-deposition material injector consisting of the vapor source 1, ionizer 2, accelerating electrode 3 and power unit is then used to inject the vapor of Pb as the vapor-deposition material by cluster ion beam deposition, and the vapor is allowed to chemically react with the activated gaseous oxygen.