Magnetic recording disk drive with laminated media and improved media signal-to-noise ratio
US6989952B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 15, 2003 |
| Grant date | Jan 24, 2006 |
| Priority date | — |
| Expiry date | Feb 17, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording disk drive has an inductive write head and a heater to record data in laminated media on the recording disk. The laminated media, with at least two ferromagnetic layers separated by a nonmagnetic spacer layer, improves SNR. Each of the ferromagnetic layers can be formed of a material having an intrinsic coercivity capable of being written by a conventional inductive write head, but because of the desired lamination to increase SNR, the ferromagnetic layer farthest from the write head is exposed to a magnetic field less than its intrinsic coercivity and thus can not be written. To write to the laminated media, heat is directed to the lower ferromagnetic layer to reduce its intrinsic coercivity below the magnetic field to which it is exposed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.