Laminated thin film disk for longitudinal recording
US6077586A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 15, 1997 |
| Grant date | Jun 20, 2000 |
| Priority date | — |
| Expiry date | Jul 15, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/265
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A thin film disk with laminated magnetic layers, for use in a disk drive, is described which exhibits a single switching behavior resulting in a smooth hysteresis loop. This is achieved by depositing a seed layer prior to depositing the Cr or Cr alloy underlayer. The seed layer material is selected to promote a [112] PO in the underlayer and subsequently a [1010] PO in the two or more laminated magnetic layers. The [1010] PO aids in maintaining minimal Hc variations between the magnetic layers. The seed layer can be a B2 type structure material such as NiAl or FeAl or any other material which results in the [112] PO in the underlayer. The underlayer is preferably Cr or a Cr alloy; the magnetic layers are preferably CoPtCr, CoPtCrTa or CoPtCrB. The spacer layer between the magnetic layers may be made from the same material as the underlayer, but may also be different, e.g. an hexagonal crystalline material such as Ru. The disks of the invention can be manufactured in standard high volume sputtering systems by virtue of the fact the magnetic layers have a reduced dependency on substrate temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.