Layered return poles for magnetic write heads
US7933096B2 · kind B2 · utility
3Cited by
4References
22Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 26, 2007 |
| Grant date | Apr 26, 2011 |
| Priority date | — |
| Expiry date | Feb 22, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/1278
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Methods and structures for the fabrication of both thin film longitudinal and perpendicular write heads are disclosed. A unique feature of these write heads is the inclusion of layered return poles, which comprise alternating layers of 22/78 and 80/20 NiFe alloys. The alternating layers also vary in thickness, the 22/78 NiFe layers having a nominal thickness of 1500 angstroms and the 80/20 NiFe layers having a nominal thickness of about 75 angstroms. Head efficiency and signal to noise ratios are significantly improved in heads having layered return pole construction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.