Magnetic properties and microstructure of FePtB, FePt(B-Ag) granular films

Multilayers [FePt(1 nm)/B(t nm)](10) (t=0.05-0.6) were alternately deposited on a glass substrate and subsequently annealed by the rapid thermal process (RTP) at 800 degrees C for 3 min. After RTP, FePt and B layers intermix to form the FePtB film with (0 0 1) texture. The ordering degree of FePt was slightly increased with doped B. The (Fe-Pt)(100-x)B-x (x=0, 5, 10) films show perpendicular magnetization and the minor FeB phase was indexed in isotropic (Fe-Pt)(100-x)B-x (x=30, 40, 60) films. By adding Ag into (Fe-Pt)(95)B-5 film, the ordering degree was slightly increased in (Fe-Pt)(95)(B0.9Ag0.1)(5) film. In (Fe-Pt)(100-x)B-x (x=5, 10) and (Fe-Pt)(95)(B0.9Ag0.1)(5) granular films, the intermixed B or Ag atoms were diffused among FePt grain boundaries to isolate and refine FePt grains uniformly with average grain sizes of 20, 15, and 6.7 nm, respectively. (C) 2012 Elsevier B.V. All rights reserved.