Thermal stability and nanostructure of CoCrPt longitudinal recording media

Mingjun Yu, Mary F. Doerner, David J Sellmyer

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

We report a systematic study of activation volumes and their correlation with physical grain sizes and thermal stability in CoCrPt media fabricated by magnetron sputtering. Different underlayers and CoCrPt layer thicknesses were used to provide a range of lateral grain sizes, Mrδ (product of remanence Mr and film thickness δ) values, and remanence coercivities. Two methods, namely the field-sweep-rate dependence of coercivity and measurements of magnetic viscosity and irreversible susceptibility, were used to determine the activation volumes and the results obtained from the two methods are in reasonable agreement. For CoCrPt layer thickness from 10 nm to 27 nm, the activation volumes of these films range from about 3×10-18 cm3 to 5×10-18 cm3, which indicate that these films are thermally stable. Furthermore, for most samples the activation volumes are close to the volumes of the physical CoCrPt grains. This suggests that the magnetic grains in these films switch almost independently. Films with physical grain sizes small enough to approach thermal instability are also discussed.

Original languageEnglish (US)
Pages (from-to)1534-1536
Number of pages3
JournalIEEE Transactions on Magnetics
Volume34
Issue number4 PART 1
DOIs
StatePublished - Dec 1 1998

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Nanostructures
Thermodynamic stability
thermal stability
Chemical activation
recording
Remanence
activation
Coercive force
grain size
remanence
Magnetic after effect
coercivity
thermal instability
Magnetron sputtering
Film thickness
Switches
magnetron sputtering
film thickness
viscosity
magnetic permeability

Keywords

  • Cocrpt
  • Longitudinal recording media, nanostructure
  • Thermal stability

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Physics and Astronomy (miscellaneous)

Cite this

Thermal stability and nanostructure of CoCrPt longitudinal recording media. / Yu, Mingjun; Doerner, Mary F.; Sellmyer, David J.

In: IEEE Transactions on Magnetics, Vol. 34, No. 4 PART 1, 01.12.1998, p. 1534-1536.

Research output: Contribution to journalArticle

Yu, Mingjun ; Doerner, Mary F. ; Sellmyer, David J. / Thermal stability and nanostructure of CoCrPt longitudinal recording media. In: IEEE Transactions on Magnetics. 1998 ; Vol. 34, No. 4 PART 1. pp. 1534-1536.
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