DYNAMIC BEHAVIOR OF COBALT GRANULES WITH ANNEALING TREATMENT IN ION-BEAM COSPUTTERED CO22AG78 GRANULAR FILM

The dynamic behavior of ferromagnetic cobalt granules in ion-beam cosp uttered Ca22Ag78 samples under annealing treatment was examined by tra nsmission electron microscopy (TEM), using a real-time video recording system. Cobalt granules about 10 nm in average size were embedded in a nonmagnetic silver matrix. It was observed that, in situ, the cobalt granules changed continually in shape and size with annealing tempera ture and time. We have estimated the changes of cobalt granule size fr om the results of TEM. The ferromagnetic resonance method was employed to study the evolution of the shapes of cobalt granules. It shows tha t cobalt granule shapes and sizes change mainly along the plane of the film during the process of annealing. (C) 1995 American Institute of Physics.