PURPOSE: To improve vertical magnetization property by using a magnetic thin- film consisting of cobalt, phosphorus and vanadium to reduce C axis dispertion in the vertical direction of the cobaltiferous magnetic thin-film.

CONSTITUTION: A magnetic thin-film consists of cobalt, phosphorous and vanadium. The cobalt content may be 70W80wt%, particularly 71W85wt%. The phosphorous content may be 1W10wt%, particularly 2W8wt%. And the vanadium content may be 11W19wt%, particularly 13W17wt%. The magnetic thin-film of such a composition has a thickness generally 0.5W2μm, preferably 0.5W1μm. In such a manner, the C axis dispersion in the vertical direction can be reduced to improve the vertical magnetization property.