Antiferromagnetically coupled magnetic recording medium with dual-layered upper magnetic layer
US6759138B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 2, 2002 |
| Grant date | Jul 6, 2004 |
| Priority date | — |
| Expiry date | Jul 2, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a magnetic recording medium which includes a base body (1-4), first and second magnetic layers (5 and 7), each being of a ferromagnetic material, and a spacer layer (6) formed between the first and the second magnetic layers for inducing antiferromagnetic exchange interaction between the first and the second magnetic layers, the second magnetic layer located farther from the base body than the first magnetic layer includes a primary layer (72) and a secondary layer (71) located nearer to the base body than the primary layer. The primary layer has a primary anisotropic magnetic field while the secondary layer has a secondary anisotropic magnetic field which is smaller than the primary anisotropic magnetic field. The first magnetic layer is for controlling the antiferromagnetic exchange interaction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.