Soft underlayer for heat assisted magnetic recording media
US9824711B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 25, 2014 |
| Grant date | Nov 21, 2017 |
| Priority date | — |
| Expiry date | Aug 13, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/73923
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A soft underlayer (SUL) and methods for making an SUL are provided, the SUL having characteristics that make it compatible with the high temperature requirements associated with heat-assisted magnetic recording (HAMR) media growth and writing, e.g., temperatures greater than 500° C. The SUL may have a high crystallization temperature of greater than 450° C. and a high Curie temperature greater than 300° C., for example. Additionally, the SUL can maintain a saturation magnetization value greater than, e.g., 9 kGauss, at such high temperatures, thereby having the ability to remain amorphous at temperatures up to, e.g., 650° C., and exhibiting a relatively flat integrated noise profile from approximately 300° C. to 650° C. Further still, a spacer layer material is chosen such that inter-diffusion does not occur at these high temperatures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.