Patent · US Expired

Containing an AITa or AITi pre-seed layer, a CoCr onset layer and a CoCrPtB magnetic layer

US6607842B2 · kind B2 · utility

5Cited by
11References
48Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 9, 2001
Grant dateAug 19, 2003
Priority date
Expiry dateAug 17, 2021

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/265
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The thin film disk includes a pre-seed layer of amorphous or nanocrystalline structure which may be AlTi or AlTa, and that is deposited upon a disk substrate. The pre-seed layer is followed by the RuAl seed layer, a Cr alloy underlayer, an onset layer composed essentially of CoCr and a magnetic layer. The onset layer has an optimal concentration of 28-33 at. % Cr and an optimal thickness of 0.5 to 2.5 nm and it increases coercivity and improves the Signal-to-Noise Ratio (SNR) of the disk. The magnetic layer is comprised of CoPtxCrBy, wherein x is the at. % concentration of Pt, y is the at. % concentration of boron, and x>4+y.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.