PURPOSE: To form a thin magnetic metallic film having excellent magnetic characteristics easily by heating the area of a substrate where deposition is going to begin in the stage of depositing a material to be evaporated which comes flying over the moving substrate.

CONSTITUTION: While a substrate 4 of a plastic film is cooled according to the rotation of a cylindrical can 2, the substrate moves. In this stage, a metallic ingot 11 in a crucible 7 is heated to melt and evaporate by the electron beam 10 generated from an electron beam generator 9. At this time, the evaporated metal in an area 14 sticks to the substrate 4. Since an area 16 where a thin magnetic film is formed in an earlier stage the incident angle θ of the evaporated metal is as high as about 90°, only a film of poor crystallinity is formed. Therefore, the part around the area 16 is heated by a heating source 12 to increase the density of radiation energy and to accelerate the growth of nuclei, whereby a thin metallic film 6 having good crystallinity hence good magnetic characteristics is formed on the substrate 4.