PREPARATION AND APPLICATIONS OF MAGNETOSTRICTIVE THIN-FILMS

Amorphous magnetostrictive films of the binary compound SmxFe1-x as we ll as of the ternary compound (TbyDy1-x)(x)Fe-1-x were prepared by rf or de magnetron sputtering using either a multitarget arrangement with pure element targets or cast composite-type targets. The magnetostric tive properties of (Tb0.3Dy0.7)(0.4)Fe-0.6 and Sm0.4Fe0.6 films were i nvestigated in relation to their preparation conditions. Depending upo n these conditions (especially upon the deposition rate, the bias volt age, and the Ar sputtering pressure) amorphous films with a giant magn etostriction of about 250 ppm (-220 ppm) at 0.1 T and 400 ppm (-300 pp m) at 0.5 T for the TbDyFe (SmFe) and an in-plane magnetic easy axis c ould be prepared. In view of applications in microsystem technologies (e.g., pumps, valves, positioning elements) these films have been test ed in a simple cantilever arrangement and the predicted deflection of a magnetostrictive actuated membrane has been calculated.