THICKNESS DEPENDENCE OF THE MAGNETIC AND ELECTRICAL-PROPERTIES OF FE-SIO2 NANOCOMPOSITE FILMS

Nanocomposite Fe-80(SiO2)(20) films with thickness from 150 to 5000 An gstrom have been prepared by rf magnetron sputtering from a composite target. The crystallites in the Fe-80(SiO2)(20) films have a bcc struc ture with the average size of 46-66 Angstrom which was determined by t ransmission electron microscopy. As indicated by the thickness depende nce of resistivity, the stacking and connectivity of the crystallites depend on the thickness of the films. The magnetic properties also dep end on the microstructure which changes with the thickness of the film s. The magnetic coercivity of the films increases with the thickness o f the film, reaches a maximum, and then decreases. The maximum coerciv ity of 400 Oe at 300 K and 1200 Oe at 5 K was observed for a film with a thickness of about 700 Angstrom.