Intrinsic anisotropy of Tb-Fe films prepared by magnetron co- sputtering.

Amorphous Tb-Fe thin films have been produced by dual-gun dc magnetron cosputtering, which allows a moderate range of compositions (spanning about 20 at. percent) to be deposited in a single run under identical conditions. The films exhibit clean M-H loops and torque curves which are somewhat anomalous but show consistent trends. Films deposited at room temperature with a composition in the range 17-30 at. percent Tb showed a positive intrinsic anisotropy of roughly 3x10(6) erg/cm(3), resulting in an easy axis of magnetization that is perpendicular to the plane of the film, While films with >37 at. % Tb had a small negative intrinsic anistropy(ca. -2x10(5) erg/cm(3)).