Properties of c-axis oriented Ba-ferrite sputtered films

In this paper, the BaM films with amorphous Fe-Ba-O underlayer were prepared by FTS system. It was found that the films with the preferential orientation of c-axis can be prepared at the substrate temperature of above 525 degrees C. The crystallization temperature of the BaM films is between 475 and 500 degrees C, but the grain size is 1000 Angstrom for the film prepared at T-s of 500 degrees C and increased with increase of T-s. It was found that the preparation BaM films with small grains is very difficult by simply changing the substrate temperature. Both H-c in perpendicular direction and in-plane direction exhibited maximum values of 3.7 and 2.7 kOe, respectively, at T-s of 500 degrees C and they decreased with increase of T-s up to 575 degrees C. This reduction of H-c seems to be caused by grain growth but some magneto-static coupling between each grain also should be considered. (C) 1999 Elsevier Science B.V. All rights reserved.