Perpendicular magnetic recording (PMR) writer with minimized internal flux shunting
US9299367B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 2015 |
| Grant date | Mar 29, 2016 |
| Priority date | — |
| Expiry date | Jul 30, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/315
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A perpendicular magnetic recording (PMR) writer is disclosed wherein a 19-24 kG hot seed layer is formed between a gap layer and a 10-19 kG magnetic layer in a partially wrapped around shield structure involving side shields and trailing shield to reduce internal flux shunting, improve writability, and enable side gap and write gap dimensions 5-10 nm smaller than typical writers for conventional and shingled magnetic recording. Side shields have a bottom surface formed along a plane that is parallel to the main pole leading edge, and at a down-track distance from 50 nm above to 100 nm below the leading edge. Cross-track and down-track field gradients are improved by fully coupling the trailing shield and side shield hot seed layers. Also, side shield hot seed layers have a height <0.15 micron and less than the 10-19 kG side shield layer height to reduce internal flux shunting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.