Laminated magnetic recording media with antiferromagnetically coupled layer as one of the individual magnetic layers in the laminate
US6773834B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 2002 |
| Grant date | Aug 10, 2004 |
| Priority date | — |
| Expiry date | Aug 9, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/265
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A laminated magnetic recording medium for data storage has an antiferromagnetically-coupled (AFC) layer and a single ferromagnetic layer spaced apart by a nonferromagnetic spacer layer. The AFC layer is formed as two ferromagnetic films antiferromagnetically coupled together across an antiferromagnetically coupling film that has a composition and thickness to induce antiferromagnetic coupling. In each of the two remanent magnetic states, the magnetic moments of the two antiferromagnetically-coupled films in the AFC layer are oriented antiparallel, and the magnetic moment of the single ferromagnetic layer and the greater-moment ferromagnetic film of the AFC layer are oriented parallel. The nonferromagnetic spacer layer between the AFC layer and the single ferromagnetic layer has a composition and thickness to prevent antiferromagnetic exchange coupling. The laminated medium has improved thermal stability and reduced intrinsic media noise.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.