The magnetic properties and microstructural evolution of Zr-doped FePt allo
y films prepared by dc-magnetron sputtering were investigated. Compared to
an undoped Fe59Pt41 binary film, Zr-doped FePt alloy films showed accelerat
ed ordering transformation kinetics accompanying smaller grains: we were ab
le to fabricate a Zr-doped FePt film [e.g., (Fe59Pt41)(97)Zr-3] possessing
very fine grain size (5 nm in average) and high coercivity (7.3 kOe) within
10 min annealing at 500 degreesC. It is thought that the point defects and
lattice strain introduced by Zr-doping activated the nucleation rate of th
e ordered phase. In particular, for Zr-doped FePt films containing less tha
n 45 at. % Pt, the ordered L1(0) phase was decomposed into a disordered pha
se after excessive annealing due to the formation of a Pt-Zr compound, most
likely Pt3Zr, that reduces the effective Pt content in the ordered phase.
(C) 2001 American Institute of Physics.