Nanogranular L1(0) FePt-C-Ta2O5 composite media for perpendicular recording applications

J Nanosci Nanotechnol. 2011 Mar;11(3):2588-92. doi: 10.1166/jnn.2011.2695.

Abstract

In this report, the effect of simultaneously adding two dopants (C and Ta2O5) in FePt was investigated. (Fe55Pt45)79C21-(x vol%) Ta2O5 films (where x = 0% to 20%) were prepared using both low and high power magnetron sputtering on MgO (2 nm)/CrRu (30 nm) underlayers with in-situ heating at 350 degrees C. Films deposited at low power showed a decrease in exchange coupling with increasing Ta2O5 content. Out-of-plane coercivity of 7.2 kOe was observed even with up to 20 vol% Ta2O5. X-Ray diffraction spectra showed presence of FePt(001) texture for all compositions of Ta2O5 ranging from 0 to 20 vol% suggesting that the perpendicular anisotropy was maintained even with up to 20 vol% of dopant content. Films deposited at high power showed a different behavior with an initial increase in out-of-plane coercivity to 8.2 kOe and a reduction in exchange coupling with loop slope parameter (alpha) approaching a fully decoupled value of 1. Further increase in doping content led to deterioration in the out-of-plane coercivity, as well as an increase in the exchange coupling.

MeSH terms

  • Carbon / chemistry*
  • Equipment Design
  • Equipment Failure Analysis
  • Iron / chemistry*
  • Magnetics / instrumentation*
  • Nanostructures / chemistry*
  • Nanostructures / ultrastructure
  • Oxides / chemistry*
  • Particle Size
  • Platinum / chemistry*
  • Tantalum / chemistry*

Substances

  • Oxides
  • Platinum
  • Tantalum
  • Carbon
  • Iron
  • tantalum oxide