A hard carbon film (12) is formed by ion-beam sputtering on a surface of a substrate (11) such as glass lens or metal sheet of a magnetic disk or a plastic film of a magnetic video tape, by selecting the direction of the ion-beam in the sputtering process to be parallel with surface of the substrate (11) of a magnetic disk, and subsequently theroen a lubricative film (13), such as ZnS2 is formed also by ion-beam sputtering.
