| 摘要 |
PURPOSE:To uniformize the thickness of a film by controlling the rotating speed of a disk substrate in a relation with the height of the center of rotation from a liquid surface in such a manner as to uniformize the thickness of a plating layer to be formed on the substrate surface. CONSTITUTION:The height (h) of the center 1a of the disk substrate 1 to be formed with a magnetic film in the region of a magnetic recording layer is determined smaller than the radius r1 of the circular region at the center. On the other hand, the state in which the center 1a of the disk substrate is not immersed in the liquid surface 2a is assured in order to immerse the outside circumferential side of the disk substrate 1 earlier into a plating bath 2 than the inside circumferential side. The height (h) of the center 1a of the disk substrate 1 from the liquid surface 2a is, therefore, determined in an r1>h>0 range. If the height (h) of the disk substrate from the liquid surface 2a is determined, the rotating speed of the disk substrate is correspondingly determined. The plating layer having the uniform film thickness is thereby formed on the disk substrate surface.
|
