RECORDING CHARACTERISTICS OF BaM THIN FILMS.

Evaluations are presented of recording density when using ring heads with relatively wide apertures on thin films of different c-axis orientation used for disk media, as are evaluations of the thermal stability of Ba-ferrite (BaM) thin films. The possibility of obtaining a high recording density thin film with small c-axis orientation was clearly established. Changes in residual magnetization with respect to temperature variation were measured, revealing that when the film was left to stand for 15 h at 250 degree C, approximately 10% thermal demagnetization occurred, and the film was almost completely demagnetized at 375 degree C.