Patent · US Expired

Magnetic recording medium with improved coercivity

US5895712A · kind A · utility

6Cited by
14References
46Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 12, 1996
Grant dateApr 20, 1999
Priority date
Expiry dateSep 12, 2016

Classification

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

Abstract

The coercivity of a magnetic recording medium is increased without any substantial change in magnetic remanence by depositing a fresh non-magnetic sub-underlayer on an underlayer or composite underlayer comprising a plurality of sub-underlayers, and immediately depositing a magnetic layer on the fresh sub-underlayer. In an embodiment of the present invention, a fresh chromium sub-underlayer having a thickness of about 55 .ANG. to about 135 .ANG. is sputter deposited on a chromium underlayer in the magnetic layer deposition chamber, and a cobalt magnetic layer deposited on and within 1.2 seconds after depositing the fresh sub-underlayer.

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