Perpendicular magnetic disk apparatus
AssigneeKabushiki Kaisha Toshiba
InventorsTakeshi Abe, Yuka Aoyagi
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Abstract
According to one embodiment, there is provided a perpendicular magnetic disk apparatus including a perpendicular magnetic recording medium including a nonmagnetic substrate having a surface roughness (Ra) of 0.35 nm or less, a soft underlayer, a nonmagnetic intermediate layer having a perpendicular orientation (Δθ50) of 4° or less, and a perpendicular recording layer made of a magnetic material having perpendicular anisotropy, and a magnetic head including a write head and a magnetoresistive read head, the write head having a main pole, a return yoke, and an exciting coil, wherein a flying height (f) of the magnetic head and an average surface roughness (Ra) of the perpendicular magnetic recording medium satisfy the following relationship: f>0.61Ra2−3.7Ra+5.9.
Claims9
A perpendicular magnetic disk apparatus comprising:
- a perpendicular magnetic recording medium including a nonmagnetic substrate having a surface roughness (Ra) of 0.35 nm or less, a soft underlayer, a nonmagnetic intermediate layer having a perpendicular orientation (Δθ50) of 4° or less, and a perpendicular recording layer made of a magnetic material having perpendicular anisotropy;
- and
- a magnetic head including a write head and a magnetoresistive read head, the write head having a main pole, a return yoke, and an exciting coil,
- wherein a flying height (f) of the magnetic head and an average surface roughness (Ra) of the perpendicular magnetic recording medium satisfy the following relationship:
- f>0.61Ra2−3.7Ra+5.9.
Dependencies are inferred from the claim text.