The Tb(Fe0.55Co0.45)1.5 films were fabricated by rf magnetron sputtering from a composite
target. Samples were investigated by means of x-ray diffraction, vibrating sample magnetometer, conversion
electron M??ssbauer spectra, and magnetostriction measurements. The as-deposited film is an amorphous
alloy with a perpendicular magnetic anisotropy and an intrinsic magnetostriction ?=1080??10-6 in an
applied field of 0.7 T. In this state, it was determined that the hyperfine field Bhf=23.5 T and the cone-angle
between the Fe moment direction and the film-normal direction ?=12?. After annealing in the temperature
range of TA=250-450&C the amorphous structure still remained, however the anisotropy was changed to a
parallel one. The soft magnetostrictive behavior has also been improved by these heat treatments: the
parallel magnetostriction ??=465??10-6 was almost developed in low applied fields of less than 0.1 T and,
especially, a huge magnetostrictive susceptibility ???=d??/d(? 0H)=1.8??10-2T-1 was obtained at ?0H=15
mT. ?? 2000 American Institute of Physics.
