CAFE2O4 THIN-FILMS GROWN ON (100)MGO SUBSTRATES USING PULSED-LASER DEPOSITION

Thin films (approximate to 0.4 mu m) of cobalt ferrite (CoFe2O4) have been grown on single-crystal (100) MgO substrates using pulsed laser d eposition (PLD). The phase, orientation, and microstructure of the as- deposited films were investigated as a function of substrate temperatu re (i.e., 200-800 degrees C) at a constant oxygen deposition pressure of 30 mTorr. The as-deposited films were found to be single phase, wel l oriented, and approximately matching the stoichiometry of the target , but the cubic lattice constant of the films depended on the substrat e temperature indicating that the films were strained. The greatest ef fect of-the substrate temperature was on the magnetic properties of th e as-deposited films. At 800 degrees C, 4 pi M(s) was measured to be 5 370 G which is approximately the accepted bulk value for cobalt ferrit e. In addition, PLD cobalt ferrite films grown at substrate temperatur es of 600 and 800 degrees C exhibited a uniaxial magnetic anisotropy w ith an easy direction normal to the film plane. Films grown at 200 and 400 degrees C also exhibited a uniaxial magnetic anisotropy but posse ssed a planar easy direction. (C) 1996 American Institute of Physics.