Perpendicular anisotropy of MBE-grown FePt granular films

The [001] oriented granular Fe/sub x/Pt/sub 1-x/ films were MBE-grown on MgO [001] single crystal substrates by means of repetitional deposition and annealing of 0.5 nm layers. The physically isolated granular structure and L1/sub 0/ ordered phase was obtained by annealing above 350/spl deg/C and the grain size of 20 nm was achieved in 3 nm thick Fe/sub 38/Pt/sub 62/ film. The Fe/sub 50/Pt/sub 50/ film annealed at 450/spl deg/C exhibits large perpendicular anisotropy of 2.0/spl times/10/sup 6/ J/m/sup 3/ and large coercivity beyond 1.2 MA/m.