Method for manufacturing magnetic recording medium
View Patent ↗Embodiments of the present invention provide a manufacturing method that can form a track guide separation area of a magnetic disk substrate constituting a patterned medium represented by a discrete track medium or bit patterned medium suitable for high recording density, uniformly on the whole surface of the magnetic disk substrate, and accurately according to the mask. According to one embodiment, a soft magnetic film, an under coating film, and a magnetic film are formed on a substrate. A mask having an arbitrary pattern shape provided for forming the track guide separation area in the magnetic film is formed on the magnetic film, and the track guide separation area is formed by irradiating ions and electrons onto the surface of the magnetic film and applying an intermittent voltage to the substrate, thereby non-magnetizing the area irradiated.
1. A method for manufacturing a magnetic recording medium characterized by including:
forming a soft magnetic film and an undercoat film on a top part of a substrate;
forming at least a magnetic film and a protection film above the undercoat film;
forming, on the protection film, a mask having a pattern to form a non-magnetic area in the magnetic film;
irradiating the protection film having the mask formed thereon with ions and electrons and applying an intermittent voltage to the substrate, thereby non-magnetizing an area of the magnetic film irradiated with ions and electrons via the protection film; and
removing the mask.
2. The method for manufacturing a magnetic recording medium according to claim 1 , characterized in that a plasma beam is used to irradiate the magnetic film with ions and electrons.
3. The method for manufacturing a magnetic recording medium according to claim 1 , characterized in that in order to irradiate the magnetic film with ions and electrons, plasma is generated by arc discharge of a negative electrode having metal as its principal component, and the generated plasma is carried by a curved magnetic duct and thus supplied to the substrate.
4. The method for manufacturing a magnetic recording medium according to claim 1 , characterized in that an ion beam source and an electron supply source are simultaneously used to irradiate the magnetic film with ions and electrons.
5. The method for manufacturing a magnetic recording medium according to claim 1 , characterized in that a high-voltage pulse power supply capable of outputting at least about 5 kV in absolute terms is used to apply an intermittent voltage to the substrate.
6. The method for manufacturing a magnetic recording medium according to claim 5 , characterized in that an output voltage of the high-voltage pulse power supply is adjusted to −5 to −50 kV, thereby adjusting depth of the non-magnetized area formed in the magnetic film.
7. The method for manufacturing a magnetic recording medium according to claim 1 , characterized in that the ions are chromium ions, manganese ions or vanadium ions.
8. The method for manufacturing a magnetic recording medium according to claim 1 , characterized in that the mask is a metal thin film.
9. The method for manufacturing a magnetic recording medium according to claim 1 , characterized in that the undercoat film comprises a nickel-based alloy and the soft magnetic film comprises an iron-based alloy.