Perpendicular writer with laminated main pole
US6791796B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 2002 |
| Grant date | Sep 14, 2004 |
| Priority date | — |
| Expiry date | Dec 12, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/3153
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention is a perpendicular writer having an air-bearing surface, a main pole with an extension, and return pole, and a back gap closure intermediate the main pole extension and the return pole. The main pole includes a top magnetic layer and a soft magnetic underlayer separated by a nonmagnetic spacer. The main pole extension is in direct contact with the main pole and recessed from the air-bearing surface. The top magnetic layer forms a trailing edge of the main pole at the ABS and has a magnetic moment greater than that of the soft magnetic underlayer. Further, the top magnetic layer and the soft magnetic underlayer are antiferromagnetically coupled through the thin nonmagnetic spacer. The nonmagnetic spacer has predominantly 111-crystalline texture and promotes reduction of coercivity and grain size along with an increase of anistropy of the top magnetic layer material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.