Perpendicular magnetic recording disk with patterned servo regions and templated growth method for making the disk
US8824084B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 2014 |
| Grant date | Sep 2, 2014 |
| Priority date | — |
| Expiry date | Apr 28, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/746
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A perpendicular magnetic recording disk has servo regions that have a patterned underlayer with seed layer pillars formed on the underlayer pillars above the underlayer trenches. The underlayer is made of an oxidizable material. Magnetic recording material is located on the seed layer pillars and on an oxide layer in the underlayer trenches. The magnetic material in the trenches exhibits a magnetic field substantially less than the magnetic field exhibited by the magnetic material on the seed layer pillars, which has perpendicular magnetic anisotropy. The reduced magnetic field from the trenches results from structural differences between the magnetic material on the seed layer pillars and in the trenches, such as smaller grain size of the magnetic material on the seed layer pillars and a wider distribution of crystallographic axes of the magnetic material in the trenches. The seed layer may be made of a material substantially non-reactive with oxygen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.