MAGNETIC DISK SUBSTRATE, MAGNETIC DISK MEDIUM, PRODUCING DEVICE OF MAGNETIC DISK MEDIUM AND MAGNETIC HEAD

PROBLEM TO BE SOLVED: To form surfaces of a substrate, magnetic film and protective film into a desired state, to improve wear resistance and to decrease frictional force by cleaning the surface of a nonmagnetic substrate contaminated with org. matters and by planarizing the nonmagnetic substrate at the same time by irradiation of cluster ion beams. SOLUTION: The nonmagnetic substrate consists of a NiP plated substrate, glass substrate or the like, on which a cobalt alloy magnetic film is formed by sputtering to 25 nm film thickness and further a carbon protective film is formed by sputtering to 10 nm film thickness. The clusters are aggregation of several hundreds to several thousands of atoms of carbon, nitrogen, boron, silicon or the like, and ionized clusters as beams are injected by irradiation on the surfaces of the substrate, magnetic film and protective film. Since the diameter of each cluster is in a nm order which is very large, the clusters rapidly diffuse on the surface to give texturing and to reform with increased hardness of the outermost surface. Since the clusters have large mass, the irradiated surface is heated to a high temp. and is excellent in removing performance of org. contaminant.