抄録
The magnetic properties of top-type exchange-coupled films (glass/Ta/CoFe/IrMn/Ta) and bottom-type exchange-coupled films (glass/Ta/IrMn/CoFe/Ta) were investigated. The exchange-coupling field (Hua) of the bottom-type films just after deposition was 0, but it gradually increased at R.T., and reached a value twice as large as that of top-type films. The blocking temperature (TB) at which Hua vanished was about 320°C for the bottom-type films, which was higher than for the top-type films. A cross-sectional TEM study of the bottom-type films revealed that the IrMn layer exhibited a lamellar platelet inclined at 20°-30° to the film plane. This peculiar structure might be related to the aging phenomenon
