title: Nanogranular L1(0) FePt-C-Ta2O5 composite media for perpendicular recording applications.
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.
authors: Data Storage Institute, A *STAR (Agency for Science, Technology and Research), 5, Engineering Drive 1 (off Kent Ridge Crescent, NUS), Singapore 117608.
authors: K M
authors: KM
authors: Cher
authors: B C
authors: BC
authors: Lim
authors: J F
authors: JF
authors: Hu
authors: P W
authors: PW
authors: Lwin
authors: T J
authors: TJ
authors: Zhou
authors: J S
authors: JS
authors: Chen
mesh_terms: D002244:Carbon / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007501:Iron / Q000737:chemistry*; D008280:Magnetics / Q000295:instrumentation*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size; D010984:Platinum / Q000737:chemistry*; D013635:Tantalum / Q000737:chemistry*
chemical_list: D010087:Oxides; D010984:Platinum; D013635:Tantalum; D002244:Carbon; D007501:Iron; C078151:tantalum oxide